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Objective: To investigate longitudinal trends in fetal and offspring cardiovascular adaptation in fetal growth restriction (FGR). Design: Prospective longitudinal study. Setting: Fetal Medicine Unit. Sample: Thirty‐five FGR pregnancies and 37 healthy controls assessed as term fetuses (mean age 37 ± 1 weeks) and again in infancy (mean age 8 ± 2 months). Methods: Conventional echocardiographic techniques, tissue Doppler imaging and speckle tracking echocardiography. Main Outcome Measures: Left ventricular (LV) and right ventricular (RV) geometry and function. Echocardiographic parameters were normalised by ventricular size adjusting for differences in body weight between groups. Results: Compared to healthy controls, late FGR fetuses showed significant alterations in cardiac geometry with more globular LV chamber (LV sphericity index, 0.56 vs. 0.52), increase in biventricular global longitudinal systolic contractility (MAPSE, 0.29 vs. 0.25 mm; TAPSE, 0.42 vs. 0.37 mm) and elevated cardiac output (combined CO: 592 vs. 497 mL/min/kg, p < 0.01 for all). Indices of LV diastolic function in FGR fetuses were significantly impaired with myocardial diastolic velocities (LV A', 0.30 vs. 0.26 cm/s; IVS E', 0.19 vs. 0.16 cm/s) and LV torsion (1.2 vs. 3.5 deg./cm, p < 0.01 for all). At postnatal assessment, FGR offspring revealed persistently increased SAPSE (0.27 vs. 0.24 mm), LV longitudinal strain (−19.0 vs. −16.0%), reduced LV torsion (1.6 vs. 2.1 deg./cm) and elevated CO (791 vs. 574 mL/min/kg, p < 0.01 for all). Conclusions: Perinatal cardiac remodelling and myocardial dysfunction in late FGR fetuses is most likely due to chronic placental hypoxaemia. Persistent changes in cardiac geometry and function in FGR offspring may reflect fetal cardiovascular maladaptation that could predispose to long‐term cardiovascular complications in later life. [ABSTRACT FROM AUTHOR]

Carbon fiber-reinforced composite hydrogen storage cylinder is a key component used in hydrogen fuel cell electric vehicles. However, some micro defects such as voids and delamination are inevitable during the manufacturing process. An efficient detection method for manufacturing defects is still lacking at present. In this work, industrial computerized tomography (CT) scanning was carried out and a large number of micro delamination with scattered sizes and random locations were found in the filament winding layer. Shearography technique based on digital speckle pattern interferometry (DSPI) was used to measure the surface deformation of the cylinders. It was found that the "butterfly-shaped" interference fringes representing the anomalous responses from defects can be significantly observed at the pressure difference of 0.62%–0.69% working pressure. Also, the crack was found originated from the delamination defect with the most significant "butterfly-shaped" fringes, which leads to a large area of interlaminar destruction during the hydraulic bursting test. [Display omitted] • Plenty of delamination defects were found in composite hydrogen storage cylinders. • Shearography measurement captured "butterfly-shaped" fringes in cylinder surfaces. • Such fringes represent the anomalous responses from delamination defects. • The anomalies can be detected at 0.62–0.69% working pressure using shearography. • "Butterfly-shaped" fringes revealed crack origination in hydraulic bursting test. [ABSTRACT FROM AUTHOR]

Orbital angular momentum (OAM) beam's spatial information captured using a camera, employs millions of single-pixel detectors arranged in a two-dimensional matrix. Poses challenges in OAM detection due to significant storage requirements, reduced speed due to low frame rate, and increased post-processing time. To address this bottleneck, a novel OAM detection technique utilizing only a diffuser and a single-pixel fast photodiode (FPD) is reported. The sixteen OAM beams, l = [ − 8 + 8 ] interact with the rotating diffuser resulting in a temporally varying speckle field. The 1D temporal speckle information (TSI) has been segregated from the temporally varying 2D speckle pattern images for each beam. The segregated 1D TSI has been classified by employing a machine learning model and achieved a classification accuracy of 97.1% and 97.3% on simulated and experimental data respectively. To further validate the proposed single-pixel OAM detection method, the 1D TSI is captured directly using a FPD. The experimentally captured 1D TSI captured via photodiode has been classified by a lightweight custom-designed 1D convolutional neural network and achieved an increased classification accuracy of 96%. This approach redefines OAM detection, operating in the temporal domain with a single-pixel FPD, thereby significantly reducing storage and computational costs while promising high-speed OAM detection. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction/Aims Methods Results Discussion Diabetic peripheral neuropathy affects small nerve fibers early, but adequate evaluation has proven difficult. One method for functional assessment of small nerve fiber function is the axon‐reflex flare (ARF) response. This study aimed to 1) validate the histamine‐induced ARF response in a nonselected population with diabetes, 2) compare the response to that induced by local heating, and 3) compare both methods to an established method (quantitative sensory testing) in a nonselected population with diabetes.Thirty‐four participants with type 1 diabetes were included. The participants underwent a neurological examination, quantitative sensory testing, sural nerve conduction, and histamine‐ and heat‐induced ARF response measurements by full‐field laser speckle perfusion imaging after epidermal application of histamine and after local heating by 44° Celsius thermode, respectively. Spearman's correlations were assessed. Logistic regression was used to generate receiver operating characteristic curves using the cold detection threshold of quantitative sensory testing as reference.The histamine‐induced ARF had an area under the curve (AUC) of 0.82, a sensitivity of 67%, and a specificity of 70%. The heat‐induced ARF had an AUC of 0.40, a sensitivity of 36%, and a specificity of 57%. No significant correlation between the histamine‐ and the heat‐induced ARF responses was found.The histamine‐induced ARF response is a valid marker for small fiber neuropathy even in nonselected populations with diabetes with good agreement with established markers and can thus be used for evaluation of C‐fiber function. The lack of correlation with the heat‐induced ARF may be due to insufficient heating. [ABSTRACT FROM AUTHOR]

Background/Objectives: Reperfusion is a major determinant of skin graft viability. The contributions of the perfusion status of the wound bed, wound margin, and donor skin to the success of the skin graft are unclear. We aimed to evaluate the relationship between perfusion variables and graft necrosis extension on the scalp and lower limb. Methods: A prospective study was conducted on adults undergoing skin graft closure after skin cancer excision on the scalp (n = 22) and lower limb (n = 20). Perfusion was measured intraoperatively and non-invasively with laser speckle contrast imaging on the graft bed, margin, and donor skin. By day 28, graft necrosis extension was quantified. Results: On the scalp and lower limb, graft bed perfusion very strongly correlated with necrosis extension (r = −0.82, p < 0.001 and r = −0.94, p < 0.001, respectively). A significant correlation (r = −0.57, p = 0.01) between margin perfusion and necrosis extension was only observed on the lower limb. The donor skin perfusion and necrosis extension did not correlate in either location (p > 0.05). The graft bed perfusion explained 68% and 89% of the variation in necrosis extension on the scalp and lower limb, respectively. Regression models of necrosis extension based on graft bed perfusion were obtained. For each unit increase in the perfusion of the graft bed, a similar decrease in necrosis extension was observed on the scalp and lower limb (40 and 48 percentage points, respectively). Conclusions: Unlike the perfusion of the wound margin and donor skin, wound bed perfusion plays a significant role in skin graft viability and can predict necrosis extension. [ABSTRACT FROM AUTHOR]

The use of synthetic aperture radar (SAR) has greatly improved our ability to capture high-resolution terrestrial images under various weather conditions. However, SAR imagery is affected by speckle noise, which distorts image details and hampers subsequent applications. Recent forays into supervised deep learning-based denoising methods, like MRDDANet and SAR-CAM, offer a promising avenue for SAR despeckling. However, they are impeded by the domain gaps between synthetic data and realistic SAR images. To tackle this problem, we introduce a self-supervised speckle-aware network to utilize the limited near-real datasets and unlimited synthetic datasets simultaneously, which boosts the performance of the downstream despeckling module by teaching the module to discriminate the domain gap of different datasets in the embedding space. Specifically, based on contrastive learning, the speckle-aware network first characterizes the discriminative representations of spatial-correlated speckle noise in different images across diverse datasets, which provides priors of versatile speckles and image characteristics. Then, the representations are effectively modulated into a subsequent multi-scale despeckling network to generate authentic despeckled images. In this way, the despeckling module can reconstruct reliable SAR image characteristics by learning from near-real datasets, while the generalization performance is guaranteed by learning abundant patterns from synthetic datasets simultaneously. Additionally, a novel excitation aggregation pooling module is inserted into the despeckling network to enhance the network further, which utilizes features from different levels of scales and better preserves spatial details around strong scatters in real SAR images. Extensive experiments across real SAR datasets from Sentinel-1, Capella-X, and TerraSAR-X satellites are carried out to verify the effectiveness of the proposed method over other state-of-the-art methods. Specifically, the proposed method achieves the best PSNR and SSIM values evaluated on the near-real Sentinel-1 dataset, with gains of 0.22 dB in PSNR compared to MRDDANet, and improvements of 1.3% in SSIM over SAR-CAM. The code is available at https://github.com/YangtianFang2002/CL-SAR-Despeckling. [ABSTRACT FROM AUTHOR]

Background Severe keloids are difficult to treat. Corticosteroid injections with needles are painful and associated with frequent recurrences. Therefore, more effective, safe and patient-friendly alternative treatments are urgently needed. Objectives To assess the efficacy, tolerability and patient satisfaction of intralesional bleomycin treatment using a needle-free electronic pneumatic jet injector (EPI) in severe keloids. Methods Patients with severe keloids were included in this double-blind, randomized, placebo-controlled trial with split-lesion design. Three EPI treatments with bleomycin or saline were administered every 4 weeks in the intervention and control sides. Outcome measures were change in scar volume assessed by three-dimensional imaging, Patient and Observer Scar Assessment Scale (POSAS), skin perfusion with laser speckle contrast imaging (LSCI), spilled volume, procedure-related pain, adverse events and patient satisfaction. Results Fourteen patients (nine female, five male) were included. The estimated mean keloid volume was significantly reduced by 20% after EPI-assisted bleomycin, compared with a slight increase of 3% in the control side (P < 0.01). The estimated mean POSAS patient and observer scores decreased by respectively 28% and 20% (P = 0.03 and P = 0.001). LSCI showed no significant change in perfusion. EPI treatment was preferred over previous needle injections in 85% of patients. The estimated mean spilled volume after EPI was around 50%, and numerical rating scale pain scores were moderate. Adverse events included bruising, hyperpigmentation and transient superficial necrosis. Conclusions A course of three EPI-assisted bleomycin injections is efficacious and well tolerated in severe keloids. Moreover, EPI was preferred by most patients and may serve as a patient-friendly alternative treatment. [ABSTRACT FROM AUTHOR]

The development of affordable and reliable methods for quantitative determination of stable atomic nuclei in aqueous solutions and adjuvant agents used in tumor chemotherapy is an important task in modern pharmaceutical chemistry. This work quantified the deuterium/prothium isotope ratio in aqueous solutions through an original two-dimensional diffuse laser scattering (2D-DLS) software and hardware system based on chemometric processing of discrete interference patterns (dynamic speckle patterns). For this purpose, 10 mathematical descriptors (di), similar to QSAR descriptors, were used. Correlation analysis of bivariate "log di—D/H" plots shows an individual set of multi-descriptors for a given sample with a given D/H ratio (ppm). A diagnostic sign (DS) of differentiation was established: the samples were considered homeomorphic if 6 out of 10 descriptors differed by less than 15% (n ≥ 180). The analytical range (r = 0.987) between the upper (D/H ≤ 2 ppm) and lower (D/H = 180 ppm) limits for the quantification of stable hydrogen nuclei in water and aqueous solutions were established. Using the Spirotox method, a «safe zone» for protozoan survival was determined between 50 and 130 ppm D/H. Here, we discuss the dispersive (DLS, LALLS) and optical properties (refractive index, optical rotation angle) of the solutions with different D/H ratios that define the diffuse laser radiation due to surface density inhomogeneities. The obtained findings may pave the way for the future use of a portable, in situ diffuse laser light scattering instrument to determine deuterium in water and aqueous adjuvants. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) is a top life-threatening disease and early and sensitive detection of CAD remains a challenge. This study aimed to assess the value of three-dimensional speckle tracking imaging (3D-STI) in diagnosing CAD patients and investigate the parameters of 3D-STI associated with disease severity. Methods: A total of 260 suspected CAD patients who met the study criteria underwent coronary angiography within one week after the ultrasound examination. Based on the examination results, 142 patients were confirmed to have CAD (CAD group), while 118 patients were classified as non-CAD (NCAD group). Age, gender, family history, smoking status, diabetes, hypertension, dyslipidemia, electrocardiogram, BMI, heart rate, and left ventricular ejection fraction were compared between the two groups. Additionally, 3D-STI parameters including left ventricular global radial strain (GRS), left ventricular global longitudinal strain (GLS), left ventricular global area strain (GAS), and left ventricular global circumferential strain (GCS) were analyzed. Results: No significant differences were found between the CAD and NCAD groups in terms of demographics, smoking history, physiological measurements, and common comorbidities such as diabetes mellitus and dyslipidemia. However, when comparing the 3D-STI parameters, all four parameters, including GLS, GRS, GCS, and GAS, were significantly different in the CAD group compared to the NCAD group. The results suggest that 3D-STI parameters have diagnostic value for CAD, and their changes are associated with CAD severity. Conclusions: Combined detection of these parameters enhances diagnostic accuracy compared to individual detection. [ABSTRACT FROM AUTHOR]

Background and Aim: The objective of this study was to investigate the impact of appropriate blood pressure (BP) control on left atrial (LA) function in recently diagnosed individuals with systemic hypertension (HTN), as assessed by two-dimensional (2D) speckle echocardiography and electrocardiography. Materials and Methods: The study included 50 patients who were recently diagnosed with systemic arterial HTN and sought medical attention at Ain Shams University Hospital. The patients' demographic information, risk factors, general and local examinations, 12-lead electrocardiograms (ECG), 2D speckle tracking ECGs, and laboratory measurements were evaluated. Following six months of appropriate BP control in accordance with Joint National Committee 10, the patients were followed up. Results: Peak atrial longitudinal strain (PALS) increased in the current study, with a mean change of 35.04±4.33 to 38.92±5.52 and a P-value <0. 001. The mean peak atrial contraction, picture archiving and communication system (PACS) strain, increased from 17.38±4.67 to 20.46±4.39, with a P-value of less than 0.001. The mitral peak early (E) and septal mitral annular velocities (e') and their average E/e' decreased with a change in the mean from 8.8±0.93 to 7.8±1.16, with a P-value of less than 0.001. The mean LA stiffness index (LASI) decreased from 0.24±0.04 to 0.2±0.03, with a P-value less than 0.001. The ECG follow-up showed no discernible change in the P-wave's duration or amplitude with P-values of 0.135 and 0.785, respectively. Conclusion: The results of this study showed that patients with HTN may benefit from speckle tracking imaging to identify mild impairment of LA function. PALS, PACS, E/e', and LASI improve in hypertensive patients when BP is well controlled. Additional studies are necessary to enhance the comprehension of LA function assessed via speckle tracking echocardiography, particularly in predicting atrial fibrillation and evaluating the risk of heart failure. [ABSTRACT FROM AUTHOR]

Background Respiratory muscle function can be affected in patients with heart failure. Ultrasound can be used to assess diaphragm, the main inspiratory muscle. Speckle tracking imaging is an imaging technology providing the evaluation of tissue deformation during contraction. We aimed to evaluate the contribution of traditional echography and 2D speckle tracking imaging in the evaluation and monitoring of patients with acute heart failure (AHF). Case summary We report a series of four cases of AHF. Diaphragm ultrasound coupled with diaphragm 2D speckle tracking imaging was performed at admission and after decongestive therapy, in cardiac intensive care unit. Patients, at admission, disclosed higher diaphragm 2D strain value and higher diaphragm inspiratory motion value in the context of higher cardiac loading that significantly decrease after decongestive therapy, except for one patient. Diaphragm motion remained less than 10 mm (weakness), despite medical therapy in Cases 2, 3, and 4. Among them, 3 months later, one patient (Case 3) experienced an episode of AHF. Discussion Diaphragm ultrasound coupled with diaphragm 2D speckle tracking imaging is feasible and may be used to monitor respiratory status patients with AHF. [ABSTRACT FROM AUTHOR]

The study proposes a novel speckle interferometric method for detecting and quantifying microplastic leaching from paper cups, addressing concerns raised by the World Health Organization regarding human health risks. Hot water at varying temperatures is placed in 36 paper cups from different manufacturers, and the specklegrams of the paper cups' interior surface are recorded. The quantity of microplastics leached into water is estimated by the Neubauer chamber method, which increases with rising water temperature. Surface morphology analysis through atomic force microscopic images reveals thermal-induced melting and smearing of microplastics, decreasing roughness parameters. Co-occurrence matrix analysis of specklegrams correlates image parameters—inertia moment, homogeneity, energy, contrast, and entropy—with the microplastics count, showing surface modifications and altered pixel intensity distribution with increasing water temperature. Regression equations based on image parameters establish a strong correlation with the microplastics count, that are validated against the Neubauer chamber method. The study indicates contrast as the potential sensitive specklegram feature for microplastics detection and quantification. [ABSTRACT FROM AUTHOR]

Aim: Research studies with porcine acellular bladder matrix (PABM) showed integration of only small sized stamps in recipient bladders, however for clinical use in bladder augmentation significantly larger patches are needed. We hypothesised pre-vascularisation with omentum may be a step towards clinical translation. Method: Eight domestic pigs were operated three times 8–10 weeks apart: 1–Implantation; PABM with recorded dimensions were sutured around a tissue expanding device, wrapped in omentum and sutured to the anterior abdominal wall. 2–Augmentation; hemi-cystectomy and bladder augmentation was performed with the pre-vascularized PABM using non-absorbable suture 3–Sacrifice; The dimensions of the PABMs were measured macroscopically, the in-vivo microcirculation of the PABMs were assessed using laser speckle contrast imaging. HE staining, uroplakin 3 and CK7 immunohistochemistry was performed. Results: In seven animals, the bladder augmentation was successful without complication. One animal was lost in bowel obstruction and in two animals enteric fistula was found after the first intervention. The rectangular shape of the initial tissue expander was subsequently changed. All the seven patches were strong, compliant and had integrated with the surrounding native bladder and were 83% (48–100%) of the original patch size. Laser speckle contrast imaging already showed microcirculation at the patch edges at augmentation and this further improved towards the centre of the patches by the end of the study. Histology demonstrated acute inflammatory response with fibroblast infiltration after implantation and full coverage by urothelium was seen with positive staining for CK7 antibodies. Conclusion: Pre-vascularization of PABM in the omentum of healthy porcine models allows larger PABM patches to integrate this may be a step towards clinical application. [ABSTRACT FROM AUTHOR]

Laser speckle contrast imaging (LSCI) is an optical technique used to assess blood flow perfusion by modeling changes in speckle intensity, but it is generally limited to qualitative analysis due to difficulties in absolute quantification. Three-dimensional convolutional neural networks (3D CNNs) enhance the quantitative performance of LSCI by excelling at extracting spatiotemporal features from speckle data. However, excessive downsampling techniques can lead to significant information loss. To address this, we propose a hybrid quantum–classical 3D CNN framework that leverages variational quantum algorithms (VQAs) to enhance the performance of classical models. The proposed framework employs variational quantum circuits (VQCs) to replace the 3D global pooling layer, enabling the model to utilize the complete 3D information extracted by the convolutional layers for feature integration, thereby enhancing velocity prediction performance. We perform cross-validation on experimental LSCI speckle data and demonstrate the superiority of the hybrid models over their classical counterparts in terms of prediction accuracy and learning stability. Furthermore, we evaluate the models on an unseen test set and observe that the hybrid models outperform the classical models with up to 14.8% improvement in mean squared error (MSE) and up to 26.1% improvement in mean absolute percentage error (MAPE) evaluation metrics. Finally, our qualitative analysis shows that the hybrid models offer substantial improvements over classical models in predicting blood flow at both low and high velocities. These results indicate that the hybrid models possess more powerful learning and generalization capabilities. [ABSTRACT FROM AUTHOR]

Laser speckle contrast imaging (LSCI) is a non-invasive, powerful, and cost-effective imaging technique that has seen widespread adoption across various medical fields, particularly for blood flow imaging. While LSCI provides physicians with valuable insights into changes or occlusions in blood flow, the technique is susceptible to various factors and parameters that can impact measurement sensitivity and signal-to-noise ratio (SNR). These include the scattering of light, which can affect the quality and reliability of the LSCI data. The polarization of light holds significant promise to enhance the performance of LSCI. In this study, we employed polarization manipulation of light to investigate its impact on the performance of LSCI for measuring flow. Focusing on the application of LSCI in microcirculation within capillaries, we examined the effect of polarization control on the technique's flow measurement capabilities using a custom-designed phantom system. This phantom consisted of three tubes with inner diameters of 1.1 mm, 1.6 mm, and 2.8 mm, embedded in a polydimethylsiloxane (PDMS) matrix with optical properties similar to biological tissue. By manipulating the polarization of both the incident and reflected light, alternating between parallel and perpendicular states, we compared the performance of our LSCI system in detecting flow for different tube diameters and depths within the phantom. Our study revealed that while depth is a critical parameter influencing flow detection using LSCI, employing perpendicular polarization (between incident and reflected light) resulted in the lowest measurement error and highest SNR compared to parallel polarization and the absence of polarization control. [ABSTRACT FROM AUTHOR]

Ischemic wounds are frequently encountered in clinical practice and may be related to ischemia secondary to diabetes, peripheral artery disease and other chronic conditions. Angiogenesis is critical to the resolution of ischemia. Hydrogen sulfide (H2S) is now recognized as an important factor in this process. H2S donors NaHS and GYY4137 were incorporated into the photosensitive polymer hydrogel gelatin methacrylate and evaluated. Human umbilical vein endothelial cell (HUVEC) culture was used to quantify toxicity and angiogenesis. Sprague Dawley rats were subjected to ischemic myocutaneous flap wound creation with and without application of H2S-eluting hydrogels. Tissue perfusion during wound healing was quantified using laser speckle contrast imaging, and gene and protein expression for VEGF were evaluated. Vascular density was assessed by CD31 immunohistochemistry. Successful incorporation of sulfide compounds was confirmed by scanning electron microscopy with energy-dispersive X-ray analysis, and under physiologic conditions, detectable H2S was present for up to 14 days by high-performance liquid chromatography. HUVECs exposed to hydrogels did not demonstrate excess cytotoxicity or apoptosis. A two-fold increase in angiogenic tube formation was observed in HUVECs exposed to H2S-eluting hydrogels. Rat ischemic flap wounds demonstrated greater perfusion at 14 days, and there was greater vascularity of healed wounds compared to untreated animals. A nearly two-fold increase in VEGF mRNA and a four-fold increase in VEGF protein expression were present in wounds from treated animals. Local-regional administration of H2S represents a novel potential therapeutic strategy to promote angiogenesis and improve wound healing after tissue injury or as a result of ischemic disease. [ABSTRACT FROM AUTHOR]

X‐ray ghost imaging with a crystal beam splitter has advantages in highly efficient imaging due to the simultaneous acquisition of signals from both the object beam and reference beam. However, beam splitting with a large field of view, uniform distribution and high correlation has been a great challenge up to now. Therefore, a dedicated beam splitter has been developed by optimizing the optical layout of a synchrotron radiation beamline and the fabrication process of a Laue crystal. A large field of view, consistent size, uniform intensity distribution and high correlation were obtained simultaneously for the two split beams. Modulated by a piece of copper foam upstream of the splitter, a correlation of 92% between the speckle fields of the object and reference beam and a Glauber function of 1.25 were achieved. Taking advantage of synthetic aperture X‐ray ghost imaging (SAXGI), a circuit board of size 880 × 330 pixels was successfully imaged with high fidelity. In addition, even though 16 measurements corresponding to a sampling rate of 1% in SAXGI were used for image reconstruction, the skeleton structure of the circuit board can still be determined. In conclusion, the specially developed beam splitter is applicable for the efficient implementation of X‐ray ghost imaging. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) patients with sarcomere mutations have an increased risk of heart failure and left ventricular (LV) systolic dysfunction. We hypothesize that sarcomere mutation carriers have abnormal myocardial contractility before LV dysfunction. Therefore, we aimed to associate myocardial contractility with identified sarcomere mutations and predict genotyped HCM patients with sarcomere mutation by three-dimensional speckle tracking imaging (3D-STI). A retrospective analysis of 117 HCM patients identified 32 genotype-positive (G +) and 85 genotype-negative (G–) patients. Genotype-positive patients had higher globe circumferential strain (GCS), globe longitudinal strain (GLS), and globe radial strain (GRS) (p < 0.05), and multivariate logistic regression revealed that these variables were associated with a positive genetic status (p < 0.05). After the propensity matches other possible influencing factors, we developed three models, named Model GCS, Model GLS, and Model GRS, which could identified genotype-positive HCM patients with excellent performance (AUC of 0.855, 0.833, and 0.870 respectively, all p < 0.001). Genotype-positive HCM patients show a higher myocardial hyper-contractility status than patients without sarcomere mutations. When combined with clinical and echocardiographic markers, the 3D-STI parameters can effectively identify the likelihood of genotype-positive HCM. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

A methodology is proposed for use in the laser speckle imaging field. This methodology modified the graphical and numerical speckle pattern imaging methods to improve their extraction and discrimination capabilities when processing the embedded temporal activity in the images of laser speckle patterns. This is through enabling these methods to adapt the levels of speckle images' interval during processing to speed up the process and overcome the lack of discrimination when they deal with a complex scattering medium having regions of various scales of activity. The impact of using the new methodology on the imaging methods' performance was evaluated using graphical and numerical evaluation tests, in addition, an exceptional laser speckle imaging system was designed and implemented to undertake a series of experimental validation tests on this methodology. The evaluation and experimental validation tests show the effectiveness of this methodology on the extraction and discrimination capabilities for the standard imaging speckle pattern methods and prove its ability to provide high performance with the real images of speckle patterns. The results also show an improvement in the processing speed for both graphical and numerical methods when the adaptive levels methodology is applied to them, which reaches 78 % for the graphical and 87 % for the numerical speckle processing methods. [ABSTRACT FROM AUTHOR]

Objective: To examine the effect of intrahepatic cholestasis of pregnancy (ICP) on fetal heart morphology. Methods: This case–control study was conducted with 40 women with ICP and 54 pregnant controls. Fetal heart quantification based on speckle tracking technology was used to assess the morphology of the fetal right and left ventricles. Routine ventricular size parameters, global and 24‐segment spherical indices (SIs) were measured and compared between groups. Results: The routine fetal cardiac parameters, global and right‐ventricular SIs did not differ between the ICP and control groups. The left‐ventricular apical (segments 16‐24) SIs were lower in the ICP group than in the control group (P <.05), with no significant difference in the other left‐ventricular segments. Conclusions: Subclinical morphological changes were observed in the left ventricular apical segments of the fetal hearts in women with ICP, which indicates an intrauterine environment with high bile acid concentrations. Twenty‐four‐segment SIs can be used to effectively evaluate these changes. [ABSTRACT FROM AUTHOR]

A new method of processing polyethylene terephthalate waste into a highly dispersed polymer filler by chemical treatment in an aqueous ammonia solution has been proposed. The possibility of obtaining highly dispersed polymer filler and polymer composite materials under elevated pressure and temperature by incorporating the filler into an epoxy oligomer has been demonstrated. The size and microphase structure of dispersed modified polyethylene terephthalate were determined using optical microscopy and speckle interferometry. Infrared spectroscopy established the presence of polyamide groups on the surface and preserved polyethylene terephthalate in the center of the particles. The use of 2-(tributoxymethyl)oxirane monoepoxide demonstrated that the resulting powder is an active filler and reacts with epoxy groups at elevated temperature, enhancing the strength of the composite after formation. Some operational characteristics of the polymer composites have been determined, and the feasibility of applying the proposed methods to address the disposal of PET containers, including plastic bottles, has been shown. The conditions for producing the fillers, along with the characteristics of the obtained fillers and the polymer composites based on them, have been established. [ABSTRACT FROM AUTHOR]

Sap flow within a leaf is a critical indicator of plant vitality and health. This paper introduces an easy-to-use, non-invasive and real-time imaging method for sap microcirculation imaging. From the coherent backscattering of light on a leaf, we show that the acquisition frequency of dynamic speckle can be linked to the microcirculation speed inside the leaf. Unlike conventional methods based on speckle contrast, which use integration times long enough to observe temporal decorrelation within a single image, our approach operates in a regime where speckle patterns appear 'frozen' in each frame of a given sequence. This 'frozen' state implies that any decorrelation of the speckle pattern within a frame is negligible. However, between successive frames, decorrelation becomes substantial, and it is this inter-frame decorrelation that enables the extraction of dynamic information. In this context, the integration time primarily influences the radiometric levels, while the frame acquisition rate emerges as the key parameter for generating activity index maps. Thus, by accessing different ranges of sap flow activity levels by varying the frame acquisition rate, we reveal, in a non-invasive way, the anatomy of the leaf's circulatory network with unprecedented richness. We experimentally validate the ability of the method to characterize the vitality of a fig leaf in real time by observing the continuous decrease in sap circulation, first in the smaller vessels and then in the larger ones, following the cutting of the leaf over a 48 h period. [ABSTRACT FROM AUTHOR]

This study developed a novel dual-wavelength confocal laser speckle imaging platform. The system includes both visible and near-infrared lasers and two imaging modes: confocal and wide-field laser speckle contrast imaging. The experimental results confirm that the proposed system can be used to measure not only blood flow but also blood oxygen saturation. Additionally, we proposed a blood flow perfusion imaging method called BlingNet (a blood flow imaging CNN) based on the laser speckle contrast imaging technique and deep learning approach. Compared to the traditional nonlinear fitting method, this method has superior accuracy and robustness with higher imaging speed, making real-time blood flow imaging possible. [ABSTRACT FROM AUTHOR]

Parenteral artificial nutrition (PAN) is a lifesaving medical treatment for many patients worldwide. Administration of the wrong PAN drug can lead to severe consequences on patients' health, including death in the worst cases. Thus, their correct identification, just before injection, is of crucial importance. Since most of these drugs appear as turbid liquids, they cannot be easily discriminated simply by means of basic optical analyses. To overcome this limitation, in this work, we demonstrate that the combination of speckle pattern (SP) imaging and artificial intelligence can provide precise classifications of commercial pharmaceutical suspensions for PAN. Towards this aim, we acquired SP images of each sample and extracted several statistical parameters from them. By training two machine learning algorithms (a Random Forest and a Multi-Layer Perceptron Network), we were able to identify the drugs with accurate performances. The novelty of this work lies in the smart combination of SP imaging and machine learning for realizing an optical sensing platform. For the first time, to our knowledge, this approach is exploited to identify PAN drugs. [ABSTRACT FROM AUTHOR]

Speckle cross-correlation imaging (SCCI) method has the depth-resolved capability, benefiting from the introduction of a reference point. However, the quality of the reconstructed image is degraded due to the background noise, which becomes more prominent when imaging through dynamic scattering media. Here, we propose a composite-differential filter-assisted (CDF-SCCI) method, allowing for effectively reducing the background noise of the reconstructed image. The signal-to-background ratios of the reconstructed images by employing the CDF-SCCI method can be enhanced by a maximum of 4.15 dB (corresponding to 2.6 times) compared to the SCCI method. Furthermore, we apply the near-infrared (NIR) illumination to the imaging system of dynamic scattering media and prove that the NIR illumination not only enhances the penetration depth of imaging, but also improves the quality of reconstructed images compared to the visible illumination. The depth-resolved imaging through various dynamic biological scattering media, including the milk and anticoagulated pig blood, further demonstrates the potential application of the proposed CDF-SCCI method in biomedical imaging. [ABSTRACT FROM AUTHOR]

Background: The aim of the current study was to investigate the predictive value of a multidirectional LV strain on adverse outcomes in a large population of uncomplicated hypertensive patients who were followed for a mean period of 10 years. Methods: This retrospective study included 591 recently diagnosed hypertensive patients who underwent clinically indicated echocardiography between January 2010 and December 2014 and were followed for a mean period of 10 years. Global longitudinal, circumferential and radial strains (GLS, GCS and GRS) were measured by 2D speckle tracking imaging. The primary outcome was a MACE occurrence defined by all-cause mortality, cardiovascular mortality, myocardial infarction, coronary artery by-pass, coronary stent implantation, stroke, development of heart failure and the occurrence of atrial fibrillation during follow-up. Results: Our results showed that GLS, GCS and GRS were significantly lower in patients who experienced MACE. Age, male gender, systolic blood pressure, left ventricular hypertrophy (LVH) and left atrial enlargement (LAE) were associated with MACE occurrence. Reduced GLS [OR 1.15; 95%CI: 1.01–1.30] and reduced GCS [OR 1.1; 95%CI: 1.02–1.22] were related with MACE independently of clinical characteristics, LV systolic and diastolic function, as well as LVH. Reduced GRS was not independently associated with adverse outcomes. Conclusions: Reduced GLS and GCS were independently associated with adverse outcomes during 10-year follow-up in patients who were recently diagnosed and uncomplicated hypertensive patients at the baseline. [ABSTRACT FROM AUTHOR]

Changes in microcirculation lead to the progression of organ pathology in diabetes. Although neuroimmune interactions contribute to a variety of conditions, it is still unclear whether abnormal neural activities affect microcirculation related to diabetes. Using laser speckle contrast imaging, we examined the skin of patients with type 2 diabetes and found that their microvascular perfusion was significantly compromised. This phenomenon was replicated in a high-fat diet–driven murine model of type 2 diabetes–like disease. In this setting, although both macrophages and mast cells were enriched in the skin, only mast cells and associated degranulation were critically required for the microvascular impairment. Sensory neurons exhibited enhanced TRPV1 activities, which triggered mast cells to degranulate and compromise skin microcirculation. Chemical and genetic ablation of TRPV1+ nociceptors robustly improved skin microcirculation status. Substance P (SP) is a neuropeptide and was elevated in the skin and sensory neurons in the context of type 2 diabetes. Exogenous administration of SP resulted in impaired skin microcirculation, whereas neuronal knockdown of SP dramatically prevented mast cell degranulation and consequently improved skin microcirculation. Overall, our findings indicate a neuron–mast cell axis underlying skin microcirculation disturbance in diabetes and shed light on neuroimmune therapeutics for diabetes-related complications. Article Highlights: Impaired microcirculation is a shared feature of various complications in type 2 diabetes. Mechanisms underlying its pathology remain not fully identified. Compared with internal organs, the skin is superficial and accessible for microcirculation observation. The role neuroimmune elements play in skin microcirculation impairment associated with type 2 diabetes was investigated. Sensory neurons are hypersensitized in diabetes and induce overexpression of substance P, which triggers mast cell degranulation and consequently impairs skin microcirculation. Neuroimmune modulation sheds light on new strategies for treating microcirculation disturbance in type 2 diabetes. [ABSTRACT FROM AUTHOR]

The primary concern of synthetic aperture radar (SAR) images is speckle noise, an inherent property. The creation of speckle noise is in a granular form and its nature is multiplicative. To reduce such noise from the radar images, the researchers' primary motive is to suppress granular pattern while preserving the quality of the obtained images, thereby facilitating easier feature extraction and classification. Existing speckle-noise reduction methods often fail to preserve fine details such as edges and textures. This study proposes a fusion-based method that integrates non-linear transform-based thresholding with advanced noise reduction techniques. The proposed method is implemented on two simulated SAR images at noise variance levels of σ = from 5 to 40. The fundamental and most significant step is to analyze the effect of granular patterns in radar images before despeckling. Different performance metrics, classified into with-reference and without-reference indexes, are considered to investigate the effectiveness of the proposed despeckle method. The Signal-to-Noise Ratio (SNR) for SAR-1 at σ = 20 was observed at 16.22 dB, outperforming the next best result of 12.89 dB from the Log Compression filter. The Universal Image Quality Index (UIQI) reached 0.6987, indicating high visual quality retention across various noise levels. The proposed despeckling method demonstrated superior performance in comparison to different filters, achieving a Peak Signal-to-Noise Ratio (PSNR) improvement of up to 29.37 dB on SAR-2 at a noise variance of σ = 5, significantly higher than the best filter method's 26.70 dB. Additionally, the method achieved a Structural Similarity Index Measure (SSIM) of 0.6538, indicating superior image quality preservation. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate the utility of 2D-STI and real-time three-dimensional echocardiography (RT-3DE) in assessing changes in left atrial (LA) structure and function in patients with paroxysmal atrial fibrillation (PAF) post-radiofrequency catheter ablation (RFCA). Methods: A retrospective analysis was conducted on 44 PAF patients who underwent RFCA at BA Hospital from March 2022 to March 2023. An age- and gender-matched control group of 32 healthy individuals was also included. Comprehensive echocardiographic parameters including LA dimensions (LAAPD, LALRD), volumes (LAVmin, LAVmax), ejection fraction (LAEF), and tissue velocities (a’, Ar) were compared between groups. Post-RFCA changes in these parameters were also assessed at 1, 3, and 6 months. Results: Pre-RFCA, PAF patients demonstrated larger LA dimensions and volumes with reduced LAEF and tissue velocities compared to controls. Post-RFCA, there was a significant improvement in LAEF and left ventricular ejection fraction at 1, 3, and 6 months, with the most pronounced changes observed at 6 months. LA dimensions increased initially but then decreased from 1 to 6 months post-RFCA. Notably, strain rate (SRS, SRE, SRA) measurements in various LA segments improved progressively, with the most significant enhancements at 6 months, suggesting improved atrial mechanics. Conclusion: The application of 2D-STI and RT-3DE provides a quantitative means to evaluate the structural and functional changes in the LA of PAF patients following RFCA. The progressive improvements in LA dimensions, volumes, and strain measurements up to 6-month post-RFCA indicate the potential of these techniques in monitoring treatment efficacy and patient recovery. [ABSTRACT FROM AUTHOR]

Background: Fruit storage methods such as dynamic controlled atmosphere (DCA) technology enable adjusting the level of oxygen in the storage room, according to the physiological state of the product to slow down the ripening process. However, the successful application of DCA requires precise and reliable sensors of the oxidative stress of the fruit. In this study, respiration rate and chlorophyll fluorescence (CF) signals were evaluated after introducing a novel predictors of apples' hypoxic stress based on laser speckle imaging technique (LSI). Results: Both chlorophyll fluorescence and LSI signals were equally good for stress detection in principle. However, in an application with automatic detection based on machine learning models, the LSI signal proved to be superior, due to its stability and measurement repeatability. Moreover, the shortcomings of the CF signal appear to be its inability to indicate oxygen stress in tissues with low chlorophyll content but this does not apply to LSI. A comparison of different LSI signal processing methods showed that method based on the dynamics of changes in image content was better indicators of stress than methods based on measurements of changes in pixel brightness (inertia moment or laser speckle contrast analysis). Data obtained using the near-infrared laser provided better prediction capabilities, compared to the laser with red light. Conclusions: The study showed that the signal from the scattered laser light phenomenon is a good predictor for the oxidative stress of apples. Results showed that effective prediction using LSI was possible and did not require additional signals. The proposed method has great potential as an alternative indicator of fruit oxidative stress, which can be applied in modern storage systems with a dynamically controlled atmosphere. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Endothelial dysfunction is a pathophysiological change preceding many cardiovascular events. Measuring improvements of endothelial function is challenging when function is already optimal, which may be remediated using a physiological challenge. This study aimed to determine whether imaging assessments can detect microvascular effects of a mixed meal tolerance test (MMTT).Twenty healthy volunteers (age ≥45 and ≤70 years) underwent two MMTTs at the beginning (Day 1) and end (Day 84) of a twelve‐week period. Imaging methods included laser speckle contrast imaging (LSCI) combined with post‐occlusive reactive hyperaemia (PORH) and local thermal hyperaemia (LTH) challenges, passive leg movement ultrasonography (PLM), and sidestream dark field microscopy (SDFM). Measurements were conducted pre‐MMTT and at 5 timepoints post‐MMTT for PLM and SDFM and 3 timepoints post‐MMTT for PORH and LTH.No consistent effects of the MMTT were detected on LSCI LTH, PLM and SDFM endpoints. LSCI PORH maximum perfusion was significantly suppressed 46, 136, and 300 min post‐MMTT administration on Day 1, while residual perfusion decreased significantly 46 and 136 min post‐MMTT on Day 1. However, when repeated on Day 84, PORH endpoints were not significantly affected by the MMTT.SDFM, PLM and LSCI LTH endpoints displayed high intra‐subject variability and did not detect consistent effects of MMTT. LSCI PORH endpoints displayed the lowest intra‐subject variability of all assessed endpoints and were affected by the MMTT on Day 1, but not on Day 84. Further standardization of methods or more robust challenges to affect vascular endpoints may be needed. [ABSTRACT FROM AUTHOR]

A comparative application of major dynamic light scattering (DLS)‐based image methodologies applied to transcranial cerebral blood flow imaging is presented. In particular, the study delves into assessing capability of Laser Doppler Flowmetry (LDF), Laser Speckle Contrast Imaging (LSCI), and Diffuse Correlation Spectroscopy (DCS) in enhancing the spatial and temporal resolution of transcranial blood flow imaging. An integral part of the study is focused on the modulation of blood flow through the administration of the vasodilator drug, Sodium Nitroprusside (SNP). This pharmacological intervention facilitated a direct observation of cerebral vasculature's responsiveness to external stimuli, illuminating the physiological adaptations within the brain's microvascular architecture. Advanced LSCI processing techniques are incorporated, notably entropy and principal component analysis (PCA). Entropy is providing a quantifiable measure of the randomness and complexity within the speckle patterns of transcranial blood flow images, revealing remarkably similar outcomes with DSC approach in terms of blood flow dynamics and its quantitative evaluation. The application of PCA approach is provided a more nuanced understanding of blood flow dynamics, facilitating the identification of subtle changes induced by drug administration. This method proved instrumental in enhancing the visualization and detection of nuanced blood flow dynamics, thereby allowing for a more detailed examination of cerebral circulation alterations induced by SNP administration. The study seeks to offer a wider‐ranging insight into comprehending the translating further the concept of DLS into transcrainial blood flow vizualization and explore its practical applications, considering hardware, advanced quantitative image processing, and data acquisition. [ABSTRACT FROM AUTHOR]

Machine perfused ex-vivo organs offer an excellent experimental platform, e.g., for studying organ physiology and for conducting pre-clinical trials for drug delivery. One main challenge in machine perfusion is the accurate assessment of organ condition. Assessment is often performed using viability markers, i.e., lactate concentrations and blood gas analysis. Nonetheless, existing markers for condition assessment can be inconclusive, and novel assessment methods remain of interest. Over the last decades, several imaging modalities have given unique insights into the assessment of organ condition. A systematic review was conducted according to accepted guidelines to evaluate these medical imaging methods, focussed on literature that use machine perfused human-sized organs, that determine organ condition with medical imaging. A total of 18 out of 1,465 studies were included that reported organ condition results in perfused hearts, kidneys, and livers, using both conventional viability markers and medical imaging. Laser speckle imaging, ultrasound, computed tomography, and magnetic resonance imaging were used to identify local ischemic regions and quantify intraorgan perfusion. A detailed investigation of metabolic activity was achieved using 31P magnetic resonance imaging and near-infrared spectroscopy. The current review shows that medical imaging is a powerful tool to assess organ condition. [ABSTRACT FROM AUTHOR]

Purpose: Bladder dysfunction associated with type 2 diabetes mellitus (T2DM) includes urine storage and voiding disorders. We examined pathological conditions of the bladder wall in a rat T2DM model and evaluated the effects of the phosphodiesterase-5 (PDE-5) inhibitor tadalafil. Materials and methods: Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats and Long-Evans Tokushima Otsuka (LETO) rats were used as the T2DM and control groups, respectively. Tadalafil was orally administered for 12 weeks. Micturition behavior was monitored using metabolic cages, and bladder function was evaluated by cystometry. Bladder blood flow was evaluated by laser speckle imaging, and an organ bath bladder distention test was used to measure adenosine triphosphate (ATP) release from the bladder urothelium. The expression levels of vesicular nucleotide transporter (VNUT), hypoxia markers, pro-inflammatory cytokines and growth factors in the bladder wall were measured using real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Bladder wall contractions in response to KCl and carbachol were monitored using bladder-strip tests. Results: With aging, OLETF rats had higher micturition frequency and greater urine volume than LETO rats. Although bladder capacity was not significantly different, non-voiding bladder contraction occurred more frequently in OLETF rats than in LETO rats. Bladder blood flow was decreased and ATP release was increased with higher VNUT expression in OLETF rats than in LETO rats. These effects were suppressed by tadalafil administration, with accompanying decreased HIF-1α, 8-OHdG, IL-6, TNF-α, IGF-1, and bFGF expression. The impaired contractile responses of bladder strips to KCl and carbachol in OLETF rats with aging were restored by tadalafil administration. Conclusions: The T2DM rats had polyuria, increased ATP release induced by decreased bladder blood flow and impaired contractile function. PDE5 inhibition improved these changes and may prevent T2DM-associated urinary frequency and bladder storage and voiding dysfunctions. [ABSTRACT FROM AUTHOR]

Monitoring aircraft using synthetic aperture radar (SAR) images is a very important task. Given its coherent imaging characteristics, there is a large amount of speckle interference in the image. This phenomenon leads to the scattering information of aircraft targets being masked in SAR images, which is easily confused with background scattering points. Therefore, automatic detection of aircraft targets in SAR images remains a challenging task. For this task, this paper proposes a framework for speckle reduction preprocessing of SAR images, followed by the use of an improved deep learning method to detect aircraft in SAR images. Firstly, to improve the problem of introducing artifacts or excessive smoothing in speckle reduction using total variation (TV) methods, this paper proposes a new nonconvex total variation (NTV) method. This method aims to ensure the effectiveness of speckle reduction while preserving the original scattering information as much as possible. Next, we present a framework for aircraft detection based on You Only Look Once v8 (YOLOv8) for SAR images. Therefore, the complete framework is called SAR-NTV-YOLOv8. Meanwhile, a high-resolution small target feature head is proposed to mitigate the impact of scale changes and loss of depth feature details on detection accuracy. Then, an efficient multi-scale attention module was proposed, aimed at effectively establishing short-term and long-term dependencies between feature grouping and multi-scale structures. In addition, the progressive feature pyramid network was chosen to avoid information loss or degradation in multi-level transmission during the bottom-up feature extraction process in Backbone. Sufficient comparative experiments, speckle reduction experiments, and ablation experiments are conducted on the SAR-Aircraft-1.0 and SADD datasets. The results have demonstrated the effectiveness of SAR-NTV-YOLOv8, which has the most advanced performance compared to other mainstream algorithms. [ABSTRACT FROM AUTHOR]

Background: Rosacea has a high incidence, significantly impacts quality of life, and lacks sufficient diagnostic techniques. This study aimed to investigate the feasibility of laser speckle contrast imaging (LSCI) for measuring facial blood perfusion in patients with rosacea and to identify differences in blood flow among various facial regions associated with different rosacea subtypes. Methods: From June to December 2023, 45 patients were recruited, with 9 excluded, leaving 36 subjects: 12 with erythematotelangiectatic rosacea (ETR), 12 with papulopustular rosacea (PPR), and 12 healthy controls. The Think View multispectral imaging analyzer assessed inflammation via gray reading values across the full face and five facial areas: forehead, nose, cheeks, and chin. LSCI measured and analyzed blood perfusion in the same areas. Plasma biomarkers interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-a (TNF-a) were tested in different groups. Results: Both ETR and PPR groups showed increased average blood perfusion and facial inflammation intensity by gray values compared to controls, with statistically significant differences. Average blood perfusion of ETR and PPR groups showed increased values in the forehead, cheeks, and nose, compared to controls, and the values in the cheeks were statistically different between ETR and PPR. The facial inflammation intensity of the ETR group showed increased values in the forehead and cheeks, and the PPR group showed increased gray values in the forehead, cheeks, nose, and chin compared to controls, and the values for the cheeks, nose, and chin were statistically significantly different between ETR and PPR. Plasma biomarkers IL-6, IL-1β, and TNF-α were significantly elevated in both ETR and PPR groups compared to controls. Conclusion: LSCI is a valuable, non-invasive tool for assessing blood flow dynamics in rosacea, providing a data foundation for clinical research. Different rosacea subtypes exhibit distinct lesion distribution and blood flow patterns, and both ETR and PPR could affect all facial areas, particularly the cheeks in ETR and the forehead, nose, and chin in PPR. [ABSTRACT FROM AUTHOR]

Port wine stain (PWS) is a congenital vascular malformation that commonly occurs on the face and neck. Currently, the main treatments for port wine stain are pulsed dye laser (PDL) and photodynamic therapy (PDT). However, the efficacy evaluation of PWS mostly relies on the subjective judgement of clinicians, and it is difficult to accurately respond to many small changes after treatment. Therefore, some non-invasive and efficient efficacy assessment methods are also needed. With the continuous development of technology, there are currently many visualisation instruments to evaluate PWS, including dermoscopy, VISIA-CR™ system, reflectance confocal microscopy (RCM), high-frequency ultrasound (HFUS), optical coherence tomography (OCT), Photoacoustic imaging (PAI), laser speckle imaging (LSI) and laser Doppler imaging (LDI). Among them, there are simple and low-cost technologies such as dermoscopy and the VISIA-CR™ system, but they may not be able to observe the deeper structures of PWS. At this time, combining techniques such as HFUS and OCT to increase penetration depth is crucial to evaluate PWS. In the future, the combination of these different technologies could help overcome the limitations of a single technology. This article provides a systematic overview of non-invasive methods for evaluating treatment efficacy in port wine stains and summarises their advantages and disadvantages. [ABSTRACT FROM AUTHOR]

Dermal allyl isothiocyanate (AITC) administration and whole-body heat stress (WBHS) are two challenge models that are used to evaluate physiological mechanisms of vasodilation and pharmacological activity in humans. Their exact vasodilatory mechanisms in humans are not fully elucidated but are likely to be nitric oxide (NO)-mediated. This study aimed to evaluate whether there is overlap in the vasodilatory pathways of dermal AITC application and WBHS by combining the challenges. In this open-label interventional study, healthy volunteers underwent dermal administration of AITC twice: under basal conditions and during WBHS. Dermal blood flow (DBF) was non-invasively measured using laser speckle contrast imaging four times, once in each of the following situations: baseline, WBHS only, AITC only, and WBHS combined with AITC. A total of 12 male volunteers, aged 18– 61 years, participated in the study. Compared to baseline, following AITC application, their DBF increased by 63.43 AU (baseline: 32.55, 95% CI [17.78, 47.31] AU, AITC only: 95.97, 95% CI [81.21, 110.7] AU, p < 0.0001). During WBHS, the increase in DBF after AITC was 42.76 AU (WBHS only: 87.25, 95% CI [72.49, 102.0] AU, WBHS+AITC: 130.0, 95% CI [115.2, 144.8] AU, p < 0.0001). The combination of WBHS and AITC resulted in a lower DBF than the sum of the DBF responses to AITC and WBHS when applied separately (ED 20.67, 95% CI [− 3.532, 44.88], p = 0.0916). This might point towards the presence of an interaction in the vasodilatory mechanism of AITC application and WBHS, possibly indicating overlap in their NOS-driven vasodilatory pathways. [ABSTRACT FROM AUTHOR]

Phase-shifting speckle interferometry could achieve full-field deformation measurement of rough surfaces. To meet the dynamic requirement and further improve the accuracy, a two-step synchronous phase-shifting measurement system is established based on the polarization-sensitive phase modulation ability of a liquid crystal spatial light modulator; by multiplexing the reference wavefront, an accurate phase shift is generated between two independent recording channels, and a common-path self-reference vortex interference structure is built for precise spatial registration. Meanwhile, according to the speckle statistical principle, a novel two-frame phase-shifting algorithm as well as a two-step spatial registration strategy is presented to strengthen the robustness of intensity and position differences caused by spatial-multiplexing; thereby, accurate transient deformation can be directly obtained from phase-shifting speckle interferograms recorded before and after deformation. The effectiveness and accuracy of the proposal are validated from the out-of-plane deformation measurement experiment by comparing with the traditional two-step and four-step phase-shifting methods. The dynamic ability is exhibited through reconstructing mechanical and thermal deformations across various application scenarios. [ABSTRACT FROM AUTHOR]

In the vasculature, nitric oxide (NO) is produced in the endothelium by endothelial nitric oxide synthase (eNOS) and is critical for the regulation of blood flow and blood pressure. Blood flow may also be regulated by the formation of nitrite-derived NO catalyzed by hemoproteins under hypoxic conditions. We sought to investigate whether nitrite administration may affect tissue perfusion and systemic hemodynamics in WT and eNOS knockout mice. We found that global eNOS KO mice show decreased tissue perfusion compared to WT mice by using laser speckle contrast imaging. To study both the acute and long-term effects of sodium nitrite (0, 0.1, 1, and 10 mg/kg) on peripheral blood flow and systemic blood pressure, a bolus of nitrite was delivered intraperitoneally every 24 h over 4 consecutive days. We found that nitrite administration resulted in a dose-dependent and acute increase in peripheral blood flow in eNOS KO mice but had no effects in WT mice. The nitrite induced changes in tissue perfusion were transient, as determined by intraindividual comparisons of tissue perfusion 24-h after injection. Accordingly, 10 mg/kg sodium nitrite acutely decreased blood pressure in eNOS KO mice but not in WT mice as determined by invasive Millar catheterization. Interestingly, we found the vasodilatory effects of nitrite to be inversely correlated to baseline tissue perfusion. These results demonstrate the nitrite acutely recovers hypoperfusion and hypertension in global eNOS KO mice and suggest the vasodilatory actions of nitrite are dependent upon tissue hypoperfusion. • ENOS KO mice to have reduced tissue perfusion. • Sodium nitrite rescues tissue hypoperfusion and hypertension in eNOS KO. • Sodium nitrite has no impact on tissue perfusion or blood pressure in WT mice. • The vasodilatory actions of nitrite correlate with baseline tissue perfusion. [ABSTRACT FROM AUTHOR]

Background: In DIC studies, positional parameters and speckle size are commonly used to characterise speckle images. The influence of edge parameters is ignored. This leads to a great difference between the DIC calculation results of simulated and real images. And some contradictory results are also produced. Objective: The main objective of this paper is to investigate the effect of edge parameters. As well as to give more reasonable parameters to describe the speckle characteristics. Methods: Firstly, this paper proposes a series of more reasonable parameters to describe the speckle features based on the mathematical expression of the speckle image. Subsequently, the effect of different edge functions on the computational error of DIC is investigated. The effect of different edge functions on pre-filtering is also investigated. Finally, real speckle images are produced using Gaussian and step functions to study the difference between the simulated and real speckle images. Results: Generally, it is believed that prefiltering can reduce the computational error of DIC, but for Gaussian edges, prefiltering hardly reduces the error, whereas hybrid edges correctly exhibit this phenomenon. Although the Gaussian edge perform well in the simulation, the actual speckle images taken show that the DIC error corresponding to the camera-acquired Gaussian speckle is much larger than that of the step speckle. Conclusions: The introduction of edge parameters to describe speckle images is necessary for DIC studies. Pre-filtering always reduces the DIC error, but for Gaussian edges this property cannot be demonstrated. The most suitable edges in reality are step edges, not Gaussian edges. [ABSTRACT FROM AUTHOR]

We use non-destructive Digital Holographic Speckle Pattern Interferometry (DHSPI), post-processing image analysis and one-dimensional exponential analysis to visualize, map and describe the structural condition of a plaster-based material. The body is heated by infrared radiation for two different time windows and the cooling process that follows is monitored in time by the so-called interferograms that are developed and are the result of the superposition of the holographic recordings of the sample prior to the thermal load and at variable time intervals during the cooling process. The fringe patterns in the interferometric images reveal features and characteristics of the interior of the material, with the experimental method and the post-process analysis adopted in this work offering accuracy, sensitivity and full-field diagnosis, in a completely non-destructive manner, without the need of sampling. [ABSTRACT FROM AUTHOR]

Parts with a large depth-to-diameter ratio play a critical role in the military, aerospace, and automotive industries. However, accurately measuring their inner surface profile remains challenging owing to the lack of adequate and accurate sensors. We developed a multi-ring structured light system to obtain three-dimensional data of inner contours, such as inner diameters, which are crucial for ensuring component performance and safety. In this study, we proposed three simple yet effective techniques to improve the multi-ring beam structured measurement system. First, we designed a distortion correction method to calibrate the imaging system. Second, a two-step calibration approach was used to calibrate the multi-ring projection. Meanwhile, we benchmarked the effects of different light sources on image speckles. The calibration results demonstrated that the coefficient of determination (R-2) used for line fitting exceeded 0.999. Moreover, the measurement experimental results show that the uncertainty of less than 10 µm and the smallest measurable pipe inner diameter can reach 15 mm, demonstrating that our methods are promising for improving the accuracy of structured light optical sensing systems. This system satisfies the measurement requirements and can be immediately utilized to meet the high demand for inner contour measurements in industrial applications. [ABSTRACT FROM AUTHOR]

This study focuses on the promising use of biospeckle technology to detect water stress in plants, a complex physiological mechanism. This involves monitoring the temporal activity of biospeckle pattern to study the occurrence of stress within the leaf. The effects of water stress in plants can involve physical and biochemical changes. Some of these changes may alter the optical scattering properties of leaves. The present study therefore proposes to test the potential of a biospeckle measurement to observe the temporal evolution in different varieties of sunflower plants under water stress. An experiment applying controlled water stress with osmotic shock using polyethylene glycol 6000 (PEG) was conducted on two sunflower varieties: one sensitive, and the other more tolerant to water stress. Temporal monitoring of biospeckle activity in these plants was performed using the average value of difference (AVD) indicator. Results indicate that AVD highlights the difference in biospeckle activity between day and night, with lower activity at night for both varieties. The addition of PEG entailed a gradual decrease in values throughout the experiment, particularly for the sensitive variety. The results obtained are consistent with the behaviour of the varieties submitted to water stress. Indeed, a few days after the introduction of PEG, a stronger decrease in AVD indicator values was observed for the sensitive variety than for the resistant variety. This study highlights the dynamics of biospeckle activity for different sunflower varieties undergoing water stress and can be considered as a promising phenotyping tool. [ABSTRACT FROM AUTHOR]

Estrogens regulate numerous physiological and pathological processes, including wide-ranging effects in wound healing. The effects of estrogens are mediated through multiple estrogen receptors (ERs), including the classical nuclear ERs (ERα and ER β ), that typically regulate gene expression, and the 7-transmembrane G protein-coupled estrogen receptor (GPER), that predominantly mediates rapid "non-genomic" signaling. Estrogen modulates the expression of various genes involved in epidermal function and regeneration, inflammation, matrix production, and protease inhibition, all critical to wound healing. Our previous work demonstrated improved myocutaneous wound healing in female mice compared to male mice. In the current study, we employed male and female GPER knockout mice to investigate the role of this estrogen receptor in wound revascularization and tissue viability. Using a murine myocutaneous flap model of graded ischemia, we measured real-time flap perfusion via laser speckle perfusion imaging. We conducted histologic and immunohistochemical analyses to assess skin and muscle viability, microvascular density and vessel morphology. Our results demonstrate that GPER is crucial in wound healing, mediating effects that are both dependent and independent of sex. Lack of GPER expression is associated with increased skin necrosis, reduced flap perfusion and altered vessel morphology. These findings contribute to understanding GPER signaling in wound healing and suggest possible therapeutic opportunities by targeting GPER. [ABSTRACT FROM AUTHOR]

Introduction: Peripheral artery disease (PAD) is an increasingly common disease, causing significant complications for patients. Trimetazidine (TMZ) not only improves clinical symptoms in PAD patients but also facilitates angiogenesis in ischemic hind limbs. Our aim was to find the function of TMZ in promoting angiogenesis and tissue perfusion in ischemic rat skeletal muscle. Methods: The rats underwent femoral artery ligation (FAL) and then treated with TMZ and saline. Hematoxylin-eosin and Masson's trichrome stain in the ischemic gastrocnemius muscle to analyze muscle morphology and atrophy. To identify angiogenesis and the tissue perfusion, CD31 immunohistochemical staining and laser speckle contrast imaging was conducted. Additionally, hind limb motor ability was measured. Finally, qRT-PCR and Western blotting were used to statistically analyze the expression levels of HIF-1α and VEGF. Results: Our study demonstrated significant enhancement in angiogenesis and tissue perfusion after FAL when treated with TMZ compared to the saline group. Histologically, it mitigates ischemia-induced muscle atrophy and inflammation, as well as reduces fibrosis progression in the TMZ group. Additionally, hind limb motor ability improved in rats treated with TMZ during motor experiments. Discussion: It suggests that TMZ can promote angiogenesis and improve tissue perfusion in ischemic skeletal muscle of rats by activating the HIF-1α/VEGF signaling pathway. Additionally, it leads to significant improvement in ischemia-induced motor limitations in the hind limbs of rats. [ABSTRACT FROM AUTHOR]

In this study, composites obtained through low-temperature carbonization of elastomeric matrix highly filled with graphite, carbon black and short carbon fibers were studied for the purpose of determining residual stresses at different scales using a combination of several complementary methods. The state-of-the-art techniques included X-ray stress analysis using the sin2 ψ method, the micro-ringcore technique via Focused Ion Beam milling and Digital Image Correlation (FIB-DIC), the contour method, the strain gauge method, and the hole drilling technique with digital laser speckle pattern interferometry (DLSPI). It was found that the contour method could not be used implemented for residual stress evaluation due to the low electrical conductivity of composite. Moreover, the DLSPI hole drilling method did not reveal any fringes indicating significant residual stress level exceeding a few MPa. The strain gauge method also revealed a narrow residual stress distribution with an average value of approximately zero. In contrast, the X-ray sin2 ψ method as well as FIB-DIC technique both returned values of about 150-250 MPa. A hierarchical model of the composite is proposed based on the Davidenkov Type I-II-III stress classification that provides an explanation of these observations. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) persists as a substantial clinical dilemma, largely because of the absence of effective treatments. This challenge is exacerbated by the hindered clearance of intracranial metabolic byproducts and the continual accrual of deleterious proteins. The glymphatic system (GS) and meningeal lymphatic vessels (MLVs), key elements of the intracranial lymphatic network, play critical roles in the clearance of harmful substances. Cannabidiol (CBD) has shown promise in reducing metabolite overload and bolstering cognitive performance in various neurodegenerative diseases. The precise mechanisms attributing to its beneficial effects in TBI scenarios, however, are yet to be distinctly understood. Utilizing a fluid percussion injury paradigm, our research adopted a multifaceted approach, encompassing behavioral testing, immunofluorescence and immunohistochemical analyses, laser speckle imaging, western blot techniques, and bilateral cervical efferent lymphatic ligation. This methodology aimed to discern the influence of CBD on both neurological outcomes and intracranial lymphatic clearance in a murine TBI model. We observed that CBD administration notably ameliorated motor, memory, and cognitive functions, concurrently with a significant reduction in the concentration of phosphorylated tau protein and amyloid-β. In addition, CBD expedited the turnover and elimination of intracranial tracers, increased cerebral blood flow, and enhanced the efficacy of fluorescent tracer migration from MLVs to deep cervical lymph nodes (dCLNs). Remarkably, CBD treatment also induced a reversion in aquaporin-4 (AQP-4) polarization and curtailed neuroinflammatory indices. A pivotal discovery was that the surgical interruption of efferent lymphatic conduits in the neck nullified CBD's positive contributions to intracranial waste disposal and cognitive improvement, yet the anti-neuroinflammatory actions remained unaffected. These insights suggest that CBD may enhance intracranial metabolite clearance, potentially via the regulation of the intracranial lymphatic system, thereby offering neurofunctional prognostic improvement in TBI models. Our findings underscore the potential therapeutic applicability of CBD in TBI interventions, necessitating further comprehensive investigations and clinical validations to substantiate these initial conclusions. [ABSTRACT FROM AUTHOR]