Search Results (57)

Background/Objectives: In septic shock, microcirculatory dysfunction contributes to organ failure and mortality. While sidestream dark-field (SDF) imaging is the reference method for assessing microvascular perfusion, its complexity limits routine use. This study evaluates near-infrared spectroscopy (NIRS) with vascular occlusion testing (VOT) as a potential bedside tool for monitoring microcirculatory changes following fluid resuscitation. Methods: Sixty-three fluid-responsive patients with sepsis were randomized to receive either 20% albumin or crystalloid. NIRS-VOT and sublingual SDF measurements were obtained at baseline and 60 min post-resuscitation. The reoxygenation slope (ReOx) derived from NIRS was calculated and compared with clinical severity scores and SDF-derived microcirculatory parameters. Results: ReOx significantly increased from baseline to 60 min in the albumin group (p = 0.025), but not in the crystalloid group. However, between-group differences at 60 min were not statistically significant. ReOx at 60 min was inversely correlated with APACHE II score (ρ = −0.325) and lactate (ρ = −0.277) and showed a weak inverse trend with norepinephrine dose. AUROC for ICU survival based on ReOx was 0.616. NIRS ReOx showed weak correlations with SDF parameters, including the number of crossings (p = 0.03) and the consensus proportion of perfused vessels (CPPV; p = 0.004). Conclusions: NIRS-VOT detected microcirculatory trends after albumin administration but showed limited agreement with SDF imaging. These findings suggest that NIRS and SDF assess different physiological domains. Further studies are warranted to define the clinical utility of NIRS as a microcirculation monitoring tool (Clinicaltrials.gov: NCT05357339). Full article

The marine habitats of the world’s oceans are being driven beyond their resilience. The ongoing biodiversity crisis is happening fast, within the lifespan of researchers trying to produce the information necessary for the conservation of habitats and marine ecosystems. Here, we report on the destruction of sciaphilic sessile communities and coralligenous concretions produced by the anchoring of a high-tonnage vessel inside a Marine Protected Area in Cyprus. The damage from the anchors and the chains consisted of the dislodgement of large boulders that were dragged or rolled over the seafloor, increasing the breakage and further dislodgement of more boulders; many were left upside-down. The biological communities that thrived in the dark environments below the boulders were directly exposed to high irradiance levels and went through a slow mortality and decaying process, most probably due to a combination of several deterioration agents, such as exposure to direct sunlight, predation, mucilage aggregates, and cyanobacterial blooms. The enforcement of regulatory measures for anchoring and transit in the MPA is necessary to prevent similar destruction. Given the extent of the irreversible damage to these sciaphilic communities, our study is, unfortunately, another environmental post-mortem contribution. Full article

Dark ships, vessels deliberately disabling their AIS signals, constitute a grave maritime safety hazard, with detection efforts hindered by issues like over-reliance on AIS, inadequate surveillance coverage, and significant mismatch rates. This paper proposes an improved multi-feature association method that integrates satellite remote sensing and AIS data, with a focus on oriented bounding box course estimation, to improve the detection of dark ships and enhance maritime surveillance. Firstly, the oriented bounding box object detection model (YOLOv11n-OBB) is trained to break through the limitations of horizontal bounding box orientation representation. Secondly, by integrating position, dimensions (length and width), and course characteristics, we devise a joint cost function to evaluate the combined significance of multiple features. Subsequently, an advanced JVC global optimization algorithm is employed to ensure high-precision association in dense scenes. Finally, by integrating data from Gaofen-6 (optical) and Gaofen-3B (SAR) satellites, a day-and-night collaborative monitoring framework is constructed to address the blind spots of single-sensor monitoring during night-time or adverse weather conditions. Our results indicate that the detection model demonstrates a high average precision (AP50) of 0.986 on the optical dataset and 0.903 on the SAR dataset. The association accuracy of the multi-feature association algorithm is 91.74% in optical image and AIS data matching, and 91.33% in SAR image and AIS data matching. The association rate reaches 96.03% (optical) and 74.24% (SAR), respectively. This study provides an efficient technical tool for maritime safety regulation through multi-source data fusion and algorithm innovation. Full article

Shadow fleets, operating covertly in global maritime commerce, have emerged as a significant challenge to international regulatory frameworks and trade policies. This paper introduces a novel conceptual framework that distinguishes between ‘dark fleets’ and ‘gray fleets’, offering a more nuanced understanding of these clandestine maritime activities. Through a comprehensive methodological approach integrating a literature review, case studies, and data analysis, we examine the characteristics, operational strategies, and implications of shadow fleets. Our research reveals that shadow fleets have expanded rapidly, now accounting for approximately 10% of global seaborne oil transportation. We identify key indicators of shadow fleet operations, including disabled Automatic Identification System (AIS) transmitters, inconsistent vessel information, unusual behavior patterns, obscure ownership structures, and the use of aging vessels. This paper highlights the economic disruptions caused by shadow fleets, their role in circumventing international sanctions, and the significant environmental and safety risks they pose. The study underscores the regulatory challenges in addressing shadow fleets, particularly their exploitation of flags of convenience and complex ownership structures. We propose a multifaceted approach to tackling these challenges, emphasizing the need for advanced technological solutions, enhanced international collaboration, and adaptive ocean governance frameworks. This research contributes to the evolving field of maritime security and policy, offering insights for policymakers, industry stakeholders, and researchers into developing strategies to mitigate the risks posed by shadow fleets in global maritime commerce. Full article

Background: Capillary tortuosity is a morphological variant of microcirculation. However, the mechanisms by which tortuous vessels meet metabolic requirements in health and disease remain unknown. We recently reported that capillary tortuosity score (CTS) is significantly higher in patients with septic shock than in steady-state individuals, and that CTS is significantly associated with alveolar-to-arterial oxygen (A-a O₂) gradient and oxygen debt in septic shock patients. Objective: We aimed to investigate the characteristics of the magnetic fields in the sublingual microcirculation of individuals with normal physiology and patients with septic shock. Methods: Systemic hemodynamics were recorded, and sublingual microcirculation was monitored using sidestream dark field (SDF+) imaging. The number of capillary red blood cells (N_RBC), the intensity of the magnetic field of a red blood cell (H_RBC), the intensity of the magnetic field of each capillary (H_CAP), and the intensity with which the magnetic field of a capillary acts on an RBC (F_CAP) were calculated. Results: Significant differences in macro- and microhemodynamic variables were observed between the two groups. Although N_RBC was significantly higher in individuals with steady-state physiology [87.4 (87.12) vs. 12.23 (6.9)], H_RBC was significantly stronger in patients with septic shock [5.9 × 10⁻¹⁶ (6.9 × 10⁻¹⁶) A m⁻¹ vs. 1.6 × 10⁻¹⁵ (1.4 × 10⁻¹⁵) A m⁻¹]. No significant difference was observed in H_CAP [2.16 × 10⁻¹⁴ (2.17 × 10⁻¹⁴) A m⁻¹ vs. 1.34 × 10⁻¹⁴ (1.23 × 10⁻¹⁴) A m⁻¹] and F_CAP [1.66 × 10⁻²⁴ (3.36 × 10⁻²⁴) A m⁻¹ vs. 6.44 × 10⁻²⁵ (1.1 × 10⁻²⁴) A m⁻¹] between the two groups. In patients with septic shock, H_RBC was associated with De Backer score (rho = −0.608) and venous–arterial carbon dioxide difference (rho = 0.569). In the same group, H_CAP was associated with convective oxygen flow (rho = 0.790) and oxygen extraction ratio (rho = −0.596). Also, F_CAP was significantly associated with base deficit (rho = 0.701), A-a O₂ gradient (rho = 0.658), and oxygen debt (rho = −0.769). Conclusions: Despite the microcirculatory impairment in patients with septic shock, H_RBC was significantly stronger in that group than in steady-state individuals. Also, H_CAP and F_CAP were comparable between the two groups. Tortuous vessels may function as biomagnetic coils that amplify RBC-induced magnetic fields, enhancing perfusion and oxygenation of adjacent tissues. Full article

All over the world, many ports have implemented surveillance camera systems to monitor the vessels and activities around them. These types of systems are not very effective in accurately detecting activities around the port due to background noise and congestion interference at the sea surface. This is why it is difficult to accurately detect vessels, especially smaller vessels, when it turns dark. It is known that some vessels do not comply with maritime rules, particularly in port and safety zones; these must be detected to avoid incidents. For these reasons, in this study, we propose and develop an improved multi-structural morphology (IMSM) approach to eliminate all of this noise and interference so that vessels can be accurately detected in real time. With this new approach, the target vessel is separated from the sea surface background through the weighted morphological filtering of several datasets of structural components. Then, neighborhood-based adaptive fast median filtering is used to filter out impulse noise. Finally, a characteristic morphological model of the target vessel is established using the connected domain; this allows the sea surface congestion to be eliminated and the movement of vessels to be detected in real time. Multiple tests are carried out on a small and discrete area of moving vessels. The results from several collected datasets show that the proposed approach can effectively eliminate background noise and congestion interference in video monitoring. The detection accuracy rate and the processing time are improved by approximately 3.91% and 1.14 s, respectively. Full article

Sea fog reduces visibility to less than 1 km and is a major cause of maritime accidents, particularly affecting the navigation of small fishing vessels as it forms when warm, moist air moves over cold water, making it difficult to predict. Traditional visibility measurement tools are costly and limited in their real-time monitoring capabilities, which has led to the development of video-based algorithms using cameras. This study introduces the Approximating and Eliminating the Airlight–Reduced DCP (AEA-RDCP) algorithm, designed to address the issue where sunlight reflections are mistakenly recognized as fog in existing video-based sea fog intensity measurement algorithms, thereby improving performance. The dataset used in the experiment is categorized into two types: one consisting of images unaffected by sunlight and another consisting of maritime images heavily influenced by sunlight. The AEA-RDCP algorithm enhances the previously researched RDCP algorithm by effectively eliminating the influence of atmospheric light, utilizing the initial stages of the Dark Channel Prior (DCP) process to generate the Dark Channel image. While the DCP algorithm is typically used for dehazing, this study employs it only to the point of generating the Dark Channel, reducing computational complexity. The generated image is then used to estimate visibility based on a threshold for fog density estimation, maintaining accuracy while reducing computational demands, thereby allowing for the real-time monitoring of sea conditions, enhancing maritime safety, and preventing accidents. Full article

Cocoa flavan-3-ols affect endothelium-dependent responses in resistance vessels and microcirculation has received little attention. We tested the effects of dark chocolate consumption (396 mg total flavanols/day for 3 days) in two Groups of 10 men (18–25 years; non-smokers) each comprising equal numbers of White European (WE) and South Asian (SA) ethnicity. In Group 1, dark chocolate did not affect reactive hyperaemia in forearm muscle, but augmented muscle dilatation evoked by acute mental stress, and reactive hyperaemia and acetylcholine (ACh)-evoked dilatation in cutaneous microcirculation. Conversely, in Group 2, chocolate did not affect cutaneous reactive hyperaemia or ACh-evoked dilatation, but these responses were blunted in Group 1 relative to Group 2. Further, when Groups 1 and 2 were combined, responses were blunted in SAs relative to WEs, augmented by chocolate in SAs only. In Group 2 individuals whose ACh-evoked dilatation was attenuated by nitric oxide synthase (NOS) inhibition, ACh-evoked dilatation was not altered after chocolate, but the attenuating effect of NOS inhibition was lost. Conversely, in Group 2 individuals whose ACh-evoked dilatation was enhanced by NOS inhibition, ACh-evoked dilatation was also augmented by chocolate. We propose that in resistance and microvessels of young men, cocoa flavan-3-ols preferentially augment endothelium-dependent dilator responses whose responses are depressed by familial and lifestyle factors more prevalent in SAs than Wes. Flavan-3-ols may facilitate the NOS pathway but also influence other endothelium-dependent dilators. Full article

The diagnosis of basal cell carcinoma (BCC) in dark phototypes can be a challenging task due to the lack of relevant clues and its variable presentation. In this regard, there is growing evidence that dermoscopy may benefit the recognition of BCC even for skin of color (SoC). The objective of this review is to provide an up-to-date overview on clinical and dermoscopic patterns of BCC in SoC, also comparing such findings with those of the main clinical mimickers reported in the literature. A comprehensive search of the literature through the PubMed electronic database was carried out in order to identify papers describing the clinical and dermoscopic features of BCC in dark phototypes (IV–VI). By finding macroscopic clinical presentations of BCCs in SoC patients and any possible clinical mimickers considered in the retrieved papers, we built a differential diagnosis list and analyzed the dermoscopic findings of such conditions to facilitate the diagnosis of BCC. BCC in darker skin may present as pigmented nodular lesions, pigmented patches or plaques, ulcers, erythematous nodular lesions, erythematous plaques or patches, or scar-like lesions, depending on its subtype and body site. The differential diagnosis for BCC in patients with SoC includes squamous cell carcinoma, melanoma, nevi, adnexal tumors and sebaceous keratosis. Additionally, it differs from that of Caucasians, as it also includes lesions less common in fair skin, such as dermatosis papulosa nigra, melanotrichoblastoma, and pigmented dermatofibrosarcoma protuberans, and excludes conditions like actinic keratosis and keratoacanthoma, which rarely appear in darker skin. The resulting differences also include infectious diseases such as deep cutaneous mycosis and inflammatory dermatoses. The most prevalent differentiating dermoscopic feature for BCC includes blue, black and gray dots, though arborizing vessels still remain the predominant BCC feature, even in dark phototypes. Diagnostic approach to BCC in dark-skinned patients varies due to the prevalence of dermoscopy findings associated with hyperpigmented structures. Clinicians should be aware of such points of differentiation for a proper management of this tumor in SoC. Full article

Introduction: Diabetic ketoacidosis (DKA) is associated with volume depletion and hemodynamic alterations. Changes in systemic microcirculation during DKA have not been described so far. Methods: In this case report, we describe the evolution of sublingual microcirculatory changes, monitored using sidestream dark field (SDF) imaging during the treatment of severe diabetic ketoacidosis in a 13-year-old girl. The patient presented a pH of 6.84, a glycemia level of 27.2 mmol/L, a ketonemia level of 5.6 mmol/L, a base excess of −29.4 mmol/L, hypernatremia, hyperosmolality due to acute gastritis, and a malfunction of the glucose sensor. Sublingual microcirculation measurements using an SDF probe were initiated 60 min after the initiation of treatment, which was then repeated 2, 3, 4, 6, 12, and 24 h after treatment initiation, as well as on the day of discharge. Results: Substantial alterations of microvascular perfusion parameters, both total and small vessel densities, perfused vessel densities, and the DeBacker score, were observed during the first 6 to 12 h of treatment. The degree of microcirculatory alteration was strongly negatively correlated with calculated osmolality, sodium levels, ketone and lactate levels, and blood pressure values. Conclusions: DKA is, in its complexity, associated with a serious microcirculatory alteration. SDF imaging provides insight into the severity of the patient’s microcirculatory alteration and its evolution during treatment. Full article

During the winter of 2018, leaf blight on florist’s daisy (Chrysanthemum morifolium L.) was noticed in Egypt. The disease, which was identified as caused by Alternaria alternata, was widely spread and led to serious damage for the exportation sector of this crop. Therefore, a study was conducted to better understand what can be conducted to minimize the problem in the future. Isolates were gathered and evaluated on five chrysanthemum cultivars (i.e., ‘Feeling Green Dark’, ‘Talitha’, ‘Chrystal Regan’, ‘Arctic queen’, and ‘Podolsk Purple’) grown in a greenhouse. The objectives were to isolate and identify the phytopathogen and detect the resistant degree of these cultivars with emphasis on the early growth stages of the crop. The results showed that ‘Podolsk Purple’ was the most resistant cultivar against the different isolates during the rooting and seedling growth stages. ‘Chrystal Regan’ was very susceptible to the different isolates. In addition, the isolate from ‘Feeling Green Dark’ was the strongest, which negatively affected the chlorophyll content and its fluorescence parameters besides other measured vegetative and anatomical features. The findings indicated that the best anatomical characters of the stem and leaf, like the thickness of cuticle and cortex, stem diameter, xylem vessel diameter, and thickness of epidermis as well as lamina thickness were recorded in the ‘Podolsk Purple’ cultivar. This study highlighted that by using the right cultivars, chrysanthemum can be cultivated during the winter season under Egyptian conditions. These results can be a part of solution to overcome the leaf blight caused by A. alternata on chrysanthemum during the early growing stages. Full article

The cellular-level visualization of retinal microstructures such as blood vessel wall components, not available with other imaging modalities, is provided with unprecedented details by dark-field imaging configurations; however, the interpretation of such images alone is sometimes difficult since multiple structural disturbances may be present in the same time. Particularly in eyes with retinal pathology, microstructures may appear in high-resolution retinal images with a wide range of sizes, sharpnesses, and brightnesses. In this paper we show that motion contrast and phase gradient imaging modalities, as well as the simultaneous acquisition of depth-resolved optical coherence tomography (OCT) images, provide additional insight to help understand the retinal neural and vascular structures seen in dark-field images and may enable improved diagnostic and treatment plans. Full article

Actinic keratosis (AK), due to its widespread prevalence, as well as the possibility of progression to an invasive form of squamous cell carcinoma, requires treatment regardless of the clinical stage. New imaging techniques, such as in vivo reflectance confocal microscopy (RCM), significantly increase the accuracy of diagnosis and allow noninvasive evaluation of the therapeutic efficacy of the ongoing treatment. Our objective was to evaluate the prevalence of specific (video)dermoscopy and RCM features of pigmented and classical subtypes of AK before and after photodynamic therapy (PDT) treatment. We included patients with facial grade II AKs (25 pigmented, 275 non-pigmented) were included in the study. Skin lesions were evaluated by (video)dermoscopy and RCM at the baseline and three months after PDT. In classic AK, the most frequent dermoscopic findings were fine wavy vessels (96%), scale (92%), microerosions (48%), and “strawberry” pattern (36%), while pigmented AK was characterized mostly by “rhomboidal pattern” (80%), scale (60%), white globules (48%), “jelly sign”, and superficial pigmentation (40%). RCM’s most characteristic classic AK findings were abnormal honeycomb pattern in the spinous layer, epidermal inflammatory infiltrate, and solar elastosis that were present in 96% of lesions. Pigmented AKs presented mostly with dark central areas of parakeratosis (72%), mottled pigmentation (72%), dermal inflammatory infiltrate (64%), solar elastosis (60%), and abnormal honeycomb pattern in the spinous layer (56%). Dermoscopically, PDT resulted in complete disappearance of the “rhomboidal pattern” in both classical and pigmented AKs, “starburst pattern” and “jelly sign” in classical AKs, and inner gray halo, “rosette sign” and central crust in pigmented AKs. Three months after one PDT session, RCM evaluation showed mostly solar elastosis in both classical and pigmented AK subtypes, epidermal inflammatory infiltrate in classical AKs, and dermal inflammatory infiltrate in pigmented AKs. New noninvasive imaging techniques such as RCM and (video)dermoscopy can help practitioners better visualize the efficacy of the ongoing PDT treatment in either classical or pigmented AK subtypes. Full article

Density maps support a bird’s eye view of vessel traffic, through providing an overview of vessel behavior, either at a regional or global scale in a given timeframe. However, any inaccuracies in the underlying data, due to sensor noise or other factors, evidently lead to erroneous interpretations and misleading visualizations. In this work, we propose a novel algorithmic framework for generating highly accurate density maps of shipping activities, from incomplete data collected by the Automatic Identification System (AIS). The complete framework involves a number of computational steps for (1) cleaning and filtering AIS data, (2) improving the quality of the input dataset (through trajectory reconstruction and satellite image analysis) and (3) computing and visualizing the subsequent vessel traffic as density maps. The framework describes an end-to-end implementation pipeline for a real world system, capable of addressing several of the underlying issues of AIS datasets. Real-world data are used to demonstrate the effectiveness of our framework. These experiments show that our trajectory reconstruction method results in significant improvements up to 15% and 26% for temporal gaps of 3–6 and 6–24 h, respectively, in comparison to the baseline methodology. Additionally, a use case in European waters highlights our capability of detecting “dark vessels”, i.e., vessel positions not present in the AIS data. Full article

Potential evapotranspiration (PET) indicates if a cultivation area is suitable for planting. Currently, site-specific PET models that are based on large geographic regions are vulnerable to inaccurate predictions as a result of climate change and sudden changes in the environmental abiotic stressors that affect plant growth. For the aim of promoting the papaya Sinta F1 cultivar, the study optimized the standard Thornthwaite PET model by integrating three advanced physics-based metaheuristics and evolutionary computing, namely atom search (ASO), differential evolution (DE), and multiverse (MVO) optimizers. The PET value was optimized through minimization as a function of air temperature, light intensity, heat index, and extended heat index. As the PET value approaches 0, it indicates that there is more soil-water content that can be absorbed by plants. Based on the four cultivation treatments (uncontrolled, ASO, DE, and MVO) exposed in three replicates within 90 days, the ASO-optimized Thornthwaite PET-treated (ASO_Th) papaya plants resulted in the highest chlorophyll a and b concentrations, densest stomatal density, concentrated root and stem xylem and phloem vessels, considerable root and stem length, most formed leaf count, and strongest action potentials coming from stem membrane for both light and dark periods. This proves the applicability of the intelligent process in modifying the Thornthwaite model for plant growth promotion. Also, through the developed ASO_Th, the stem length and thickness ratio was improved for mechanical stability to facilitate more branching leaves and potential fruits during the fruiting stage, and the chlorophyll a and b ratio was enhanced, which naturally extended the light energy band for photosynthesis. Overall, the newly developed ASO_Th model may be used to grow papaya seedlings year-round anywhere on Earth if there is a control system to regulate the environmental setting inside the growth chamber. Full article