Combination Of Sea Research Articles

Links between atmospheric aerosols and sea state in the Arctic Ocean

Sea spray emission is the largest mass flux of aerosols to the atmosphere with important impact on atmospheric radiative transfer. However, large uncertainties still exit in constraining this mass flux and its climate forcing, in particular in the Arctic, where sea ice and relatively low wind speed in summer constitute a significantly different regime compared to the global ocean. Sea state conditions and marine boundary layer stability are also critical variables, but their contribution is often overlooked. Here we present concurrent observations of sea state using a novel stereo camera system, of sea spray through coarse mode aerosols, and of meteorological variables to determine boundary layer stability in the Barents and Kara Seas during the 2021 Arctic Century Expedition. Our findings reveal that aerosol concentrations were highest over open waters, closely correlating with wave height, followed by wind speed, wave steepness, and wave age. Notably, these correlations were stronger under unstable marine boundary layer conditions, reflecting immediate sea spray generation. By analysing various combinations of sea and atmospheric variables, we identified the wave height Reynolds number as the most effective indicator of atmospheric sea spray concentration, explaining 57% of its variability in unstable conditions. Our study underscores the need to consider sea state, wind, and boundary layer conditions together to accurately estimate atmospheric sea spray concentrations in the Arctic.

A combined sea and sea-ice surface temperature climate dataset of the Arctic, 1982–2021

The surface temperature is one of the main parameters for assessing climate change. Temperature change is most pronounced in the Arctic, and therefore, it is crucial to accurately estimate sea and sea ice surface temperatures in this region. The availability of in situ observations is limited in the Arctic, thus, increasing the need for satellite observations to estimate surface temperatures. We present the first Arctic (>58°N) gap-free climate dataset covering the surface temperatures of the ocean, sea ice and the marginal ice zone from 1 January 1982 to 31 May 2021 based on observations from infrared satellite sensors. The underlying algorithm combines the multi-satellite observations and performs a statistical optimal interpolation to obtain daily gap-free fields, with a spatial resolution of 0.05° in latitude and longitude. In situ observations have been used to derive consistent validation statistics over the ocean and sea ice. Comparison of the derived sea surface temperatures against in situ measurements from drifting buoys, moored buoys and Argo floats shows mean differences of 0.01 °C, 0.04 °C and 0.04 °C and standard deviations of 0.54 °C, 0.56 °C and 0.51 °C, respectively. Over sea ice, the derived ice surface temperatures have been compared with KT-19 measurements from IceBridge flights, showing a mean difference of 1.52 °C and standard deviation of 3.12 °C, and with air temperatures from the North Pole (NP) ice drifting stations as well as ECMWF distributed buoys and CRREL buoys, with mean differences of −2.35 °C, −3.21 °C and –2.87 °C and standard deviations of 3.12 °C, 3.34 °C and 3.36 °C, respectively. The combination of sea and sea-ice surface temperature provides a consistent dataset for climate analysis, which is crucial for studying climate change and trends in the Arctic. The combined sea and sea-ice surface temperature of the Arctic has risen with about 4.5 °C over the period 1982–2021, with a peak warming of around 10 °C in the northeastern Barents Sea.

Klasterisasi Staphylococcus aureus Resisten Neutrofil Berdasar Assesory Gene Regulator

Staphylococcus aureus is recognized worldwide as a major pathogen causing subclinical intramammary infections in dairy cows and food poisoning due to its ability to produce enterotoxin. The study aimed to identify enterotoxins of S. aureus and clustering the enterotoxins based on assessory gene regulator (agr). Virulence of S. aureus to the host was characterized based on the response of polymorphonuclear cells to the infection. Twelve S. aureus could be isolated from milk cows in central of dairy farming in Sumedang West Java. The identification of S. aureus was based on cultural and biochemical tests and an amplification of a specific section of the 23S rRNA gene. The sensitivity test against antibiotics revealed that some isolates of S. aureus were resistant to penicillin and methycillin. By PCR amplification one or more staphylococcal enterotoxin genes could be observed five genes in combinations of sea (216 bp), seb (478 bp), seh (375 bp), sei (576 bp), and sej (142 bp). Clustering of S. aureus based on the assesory gene regulator could be grouped into 4 clusters for agr1 (1 isolat), agr2 (2 isolates), in combination for agr1 and agr2 (1 isolate), and for non agr (2 isolates). Based on the response of polymorphonuclear cell in vitro and in vivo assays, revealed that S. aureus strain I-2 (agr1 cluster) and P1 (agr1+agr2 cluster) were more resistant to polymorphonuclear cells and could survive intracellularly, indicated that these strains could be used as proper candidates to develop dignostic tool based on agr against staphylococcal mastitis.

The effects of prolactin on ADP-induced platelet aggregation in patients with stable angina of effort and gastroesophageal reflux disease

The combination of stable angina of effort (SEA) and gastroesophageal reflux disease (GERD) is frequently observed in the clinic of internal diseases. Thrombocytic link of homeostasis is one of the main factors in the development and progression of atherosclerosis. The long-term increase of circulation prolactin levels can result in the development of pathological changes caused by hyperprolactinemia.Objective — to investigate the effect of prolactin levels on the ADP-induced platelet aggregation in patients with SEA and GERD.Materials and methods. The study included 148 persons: 30 patients with isolated SEA (1st group), 30 patients with isolated GERD (2nd group), and 88 patients with combination of SEA and GERD (3rd group). A separate group consisted of 20 practically healthy persons (PHPs). The serum levels of prolactin and the degree, rate, and time of ADP-induced platelet aggregation were investigated in all patients, included in the study.Results and discussion. The degree, rate, time of ADP­induced platelet aggregation, as well as prolactin levels, were significantly higher in patients with SEA and comorbidity of GERD than the similar results of the PHPs group, patients with isolated SEA and isolated GERD. A high direct correlation relationship was established between the degree of ADP-induced aggregation of blood platelets in patients with SEA with comorbid GERD and serum prolactin levels (r = 0.710; r = 0.696). Conclusions. It has been established that in patients with SEA with comorbid GERD, the prolactin levels were higher than in groups with isolated SEA, isolated SEA and PHPs group and increaseв proportionally to the degree and rate of ADP-induced platelet aggregation.

Scenario-Entity Analysis based on an entity-relationship model: Revisiting crime reconstruction

For a crime case, the related physical evidence and information can be termed entities, and there exist different types of relationships between entities. Entity-relationship models connect numerous entities through different relationships, which is useful in crime reconstructions. However, two types of problems may occur that can mislead crime reconstructions in the real world. Specifically, important entities may not be collected and vital relationships may go undiscovered. In this paper, we used an approach based on an entity-relationship model to address these problems. We organized the related entities used to reconstruct crimes according to their physical properties and sorted the relationships between entities through temporal, spatial and logical dimensions. The proposed approach is called ‘Scenario-Entity Analysis’ (SEA), and it uses several steps for discovering entities and relationships. The SEA also provides a framework for associating events/scenarios with evidence, which is important for crime reconstructions. Using a combination of SEA and Bayesian networks, a three-layered Bayesian network was constructed for uncertainty reasoning. A knife-attack case is then presented to demonstrate the analytical process of SEA.

Multi-use of the sea: A wide array of opportunities from site-specific cases across Europe.

The concept of multi-use of the sea has gained popularity in recent years as a result of ocean space (coastal areas and regions with relatively small sea space in particular) becoming increasingly crowded due to the development of the maritime economy. Competing claims for space can be a source of conflict, however this may also lead to mutual benefits for different users when sustainable combinations are sought. Despite increasing European-wide efforts, on-the-ground knowledge and practice of multi-use are still limited. Therefore, with the aim of investigating opportunities for multi-use development in the European seas, 10 case studies were selected, involving different site-specific contexts. This study analyses the characteristics and development potential for ocean multi-use, integrating results from desk analysis and stakeholder perceptions from different sectors in each of the case study locations. Similarities and differences between various combinations of sea uses are also identified. The results show a high heterogeneity of multi-use opportunities between case studies, with a range of combinations identified. The investigated combinations of maritime uses share an overall balance between factors promoting (drivers) and hindering (barriers) multi-use development. Based on stakeholder opinions, expected benefits (added values) of multi-use implementation outweigh potential negative impacts. Management actions are also proposed to further exploit multi-use potential at a local, regional (sub-national) and national levels.

МОЖЛИВОСТІ ЗАСТОСУВАННЯ КЛАСТЕРНОГО ПІДХОДУ ДО ОРГАНІЗАЦІЇ МУЛЬТИМОДАЛЬНИХ ПЕРЕВЕЗЕНЬ

In the article, the authors analyzed the scientific achievements of Ukrainian and foreign scientists in determining the main organizational aspects of multimodal transportation. The concept of «multimodal transportation», its main features, the process of organization and technology of multimodal transportation are studied. In the course of the research it was determined that multimodal transportation is the main trend in the development of transport services both at the global and national levels; the main participants in the implementation of multimodal transportation are indicated. The advantages and disadvantages of using multimodal transportation technology were highlighted. One of the important tasks of modernization of the transport system of Ukraine is the ability to ensure coordinated operation of all modes of transport. The combination of sea and rail transport is especially promising in Ukraine in the implementation of multimodal transport. The tasks of integrated development of transport, warehousing, terminal infrastructure, customs, cargo insurance system and their information support, the interconnection of all these components for coordinated work can be most effectively solved in multimodal transport hubs or transport and logistics centers. Multimodal transport hubs are able to ensure the operation of transport in accordance with the requirements of world standards. This will help attract additional cargo, increase budget revenues, position Ukraine in the world as a major transport power. The authors also analyzed the world practice of creating port clusters with a combination of port and railway infrastructure. It is noted that the port cluster is a concentration of logistics activities, commercial centers, information and transport hubs. The authors identified the advantages and substantiated the possibilities of applying the cluster approach, in particular the creation of a port cluster, in the implementation of multimodal transportation using a combination of sea and rail transport in Ukraine.

An MILP model for optimization of a small-scale LNG supply chain along a coastline

The world energy demand is continuously increasing and natural gas is one of the strongest candidates to cover the growth. However, natural gas is unavailable in many energy intensive areas and the best way to introduce natural gas to new, scattered, areas is by transporting it as liquefied natural gas (LNG). LNG can be shipped from a large LNG import terminal to consumers through a network of smaller satellite terminals with a combination of sea- and land-based transports. Building up a small-scale supply chain network is expensive and capital intensive. This paper presents a mathematical model to aid in the supply chain design decisions by minimizing the total costs associated with fuel procurement. The use of the model is illustrated by a case study, where the optimal supply chain of LNG for covering certain parts of the energy requirements of a country is designed under different cost structures for LNG and for its land-based transportation.

The Second Order Statistics of High Waves in Wind Sea and Swell

The statistics of extreme wave crest elevation and wave height have been calculated for realistic, directionally spread sea and swell using a probabilistic method tested and described previously. The nonlinearity of steep waves is modeled to the second order using Sharma and Dean kinematics, and a response surface (reliability type) method is used to deduce the crest elevation or wave height corresponding to a given probability of exceedance. The effects of various combinations of sea and swell are evaluated. As expected, in all cases, nonlinearity makes extreme crests higher than the corresponding linear ones. The nonlinear effects on the wave height are relatively small.

In situ measurements of hydrodynamic forces imposed on Chondrus crispus Stackhouse

Among the hydrodynamic forces experienced by intertidal organisms, drag and the impingement force are thought to have the greatest effect on macroalgae. These forces are modified by biotic factors such as algal morphology, reconfiguration, and the presence of a canopy. However, much of what is known about the hydrodynamics of macroalgae has been garnered from low-velocity laboratory flume studies. Few field studies have measured drag and none have directly measured the effects of the canopy on force. To examine in situ hydrodynamic forces imposed on the turf forming macroalga Chondrus crispus, compact digital force sensors were developed that measure and record the 3-dimensional force imposed on a macroalga without disturbing the surrounding canopy. Sensors were positioned within natural Chondrus beds and the effects of the canopy, algal morphology, and sea state on in situ hydrodynamic force were examined. Additionally, the predictions of a new model for drag on flexible macroalgae were tested by simultaneously measuring force and water velocity. Digital force recordings indicated that Chondrus only experience drag; lift and impingement force were negligible in all combinations of factors. Canopies significantly reduced drag by 15–65%. Morphology and size also influenced drag, such that lower forces were imposed on small planar algae than large arborescent individuals. Further, planar algae experienced low drag in all combinations of sea and canopy state, indicating that these individuals may not be as susceptible to wave disturbance as arborescent individuals. Overall, these data indicate that the ability for Chondrus to grow large, arborescent individuals is dependent on the drag reducing properties of the canopy, while more hydrodynamically harsh habitats may be accessible to planar morphologies. Additionally, these data suggest that drag models for canopy forming macroalgae must incorporate the effects of the canopy to predict drag accurately in situ.

An insight into the formation of severe ozone episodes: modeling the 21/03/01 event in the ESCOMPTE region

High ozone concentrations are observed more and more frequently in the lower troposphere. The development of such polluted episodes is linked to a complex set of chemical, physical and dynamical parameters that interact with each other. To improve air quality, it is necessary to understand and quantify the role of all these processes on the intensity of ozone formation. The ESCOMPTE program, especially dedicated to the numerical simulation of photochemical episodes, offers an ideal frame to investigate details of the roles of many of these processes through 3D modeling. This paper presents the analysis, with a 3D eulerian model, of a severe and local episode of ozone pollution that occurred on the 21st of March 2001 in the ESCOMPTE region. This episode is particularly interesting due to the intensity of the observed ozone peaks (450 μg/m 3 during 15 mn) but also because it did not occur in summer but at the beginning of spring. As part of the premodeling work of the ESCOMPTE program, this study focuses on the sensitivity of the simulated ozone peaks to various chemical and physical phenomena (long-range transport, industrial emissions, local dynamic phenomena…) to determine their influence on the rise of high local photooxidant concentrations and to better picture the photochemistry of the ESCOMPTE region. Through sensitivity tests to dynamical calculation resolution and emissions, this paper shows how the combination of sea and pond breezes with emissions of reactive VOCs can generate local intense ozone peaks.

Spawning induction of three tropical sea cucumbers, Holothuria scabra, H. fuscogilva and Actinopyga mauritiana

Tropical sea cucumbers, Holothuria scabra, H. fuscogilva and Actinopyga mauritiana were collected from the wild, held in insulated containers and transported by a combination of sea, air and road transport for up to 12 h. Methods for obtaining reliable supplies of fertilised eggs from wild-caught broodstock were investigated. Of the 779 H. scabra collected, 4.5% eviscerated during transport, compared with 11.0% of the 181 H. fuscogilva and none of the 52 A. mauritiana. Experiments conducted in 20-l containers, with and without sea water and temperature control, determined that H. scabra survived for over 80 h, H. fuscogilva for 8 h and A. mauritiana for 20 h, in static seawater at 29 °C. Spawning of H. scabra in Solomon Islands can be induced throughout the year, but only in 3 months for H. fuscogilva (from August to October), and 2 months for A. mauritiana (from October to November). The peak spawning period for all three species was during the dry season: August–November. Collection, transport and thermal stress was an effective spawning induction method for H. scabra and A. mauritiana. Induced egg production in H. scabra was greatest in September, when 35% of broodstock spawned. Spawning appeared to be entrained to a lunar cycle in H. scabra, and occurred more readily during the afternoon and early evening. Addition of dried Schizochytrium sp. induced spawning in H. fuscogilva and was far more effective than thermal induction. Females of all three species were highly fecund and capable of multiple spawning. The mean number of fertilised eggs was: 1.9 million (±0.6 S.E., n=17) for H. scabra; 2.6 million (±0.2 S.E., n= 5) for H. fuscogilva and 2.6 million (±0.1 S.E., n=6) for A. mauritiana. The techniques for inducing spawning identified in this study allowed the collection of fertilised eggs for experimental and pilot-scale mass production of juvenile sea cucumbers. Further research should target improved spawning induction through the conditioning and holding of captive broodstock.

Surface magnetic permeability measurements on some Taranaki ironsand deposits

Abstract Surface magnetic permeability measurements on some of the Taranaki ironsand deposits using an in situ permeability bridge are reported. The variation of iron ore concentration along the coast from Wanganui to Patea is discussed with particular reference to the effect of topographical features such as river mouths on the distribution. It is found that such features have a marked effect, indicating that sampling techniques may lead to erroneous values for the amount of iron ore present. It is concluded that the mechanism responsible for the concentration of the ironsands is probably a combination of sea- and wind-sorting, with the latter being the more efficient.