Mineral dust particles represent the most abundant component of atmospheric aerosol in terms of dry mass. They play a key role in climate and climate change, so the study of their emission processes ...is of utmost importance. Measurements of dust emission into the atmosphere are scarce, so that the dust load is generally estimated using models. It is known that the emission process can generate strong atmospheric electric fields. Starting from the data we acquired in the Sahara desert, here, we show for the first time that depending on the relative humidity conditions, electric fields contribute to increase up to a factor of 10 the amount of particles emitted into the atmosphere. This means that electrical forces and humidity are critical quantities in the dust emission process and should be taken into account in climate and circulation models to obtain more realistic estimations of the dust load in the atmosphere.
Key Points
The tight interrelation between the dust‐lifting process and atmospheric electric field is shown
The role of the relative humidity is demonstrated
Electric forces contribute to the entrainment of dust in the atmosphere
Wind‐formed features are abundant in Oxia Planum (Mars), the landing site of the 2022 ExoMars mission, which shows geological evidence for a past wet environment. Studies of aeolian bedforms at the ...landing site were focused on assessing the risk for rover trafficability, however their potential in recording climatic fluctuations has not been explored. Here we show that the landing site experienced multiple climatic changes in the Amazonian, which are recorded by an intriguing set of ridges that we interpret as Periodic Bedrock Ridges (PBRs). Clues for a PBR origin result from ridge regularity, defect terminations, and the presence of preserved megaripples detaching from the PBRs. PBR orientation differs from superimposed transverse aeolian ridges pointing toward a major change in wind regime. Our results provide constrains on PBR formation mechanisms and offer indications on paleo winds that will be crucial for understanding the landing site geology.
Plain Language Summary
Oxia Planum on Mars is the landing site for the ExoMars 2022 mission. The region likely hosted a standing body of water, but the effect of the wind was also important in shaping the landscape. In this study, we first describe a set of linear ridges that, in our interpretation, were sculpted by the wind in a more recent past. We also show that the wind that formed the ridges (Periodic Bedrock Ridges) was blowing from a different direction than the ones that formed younger ripples on top, suggesting a complex geological history of wind erosion and deposition that will be further investigated during the ExoMars mission.
Key Points
We present the first evidence for a periodic bedrock ridge (PBRs) pattern from the ExoMars 2022 landing site
Formative paleowind directions are extrapolated from PBRs and transverse aeolian ridges
Evidence for an Amazonian change in the wind regime are provided
The most common means to analyze redox gradients in sediments is by push/pulling electrochemical probes through sediment’ strata while repeating measurements. Yet, as electrodes move up and down they ...disrupt the texture of the sediment layers thus biasing subsequent measurements. This makes it difficult to obtain reproducible measurements or to study the evolution of electrochemical gradients. One solution for solving this problem is to eliminate actuators and electrode movements altogether, while instead deploying probes with numerous electrodes positioned at various depths in the sediment. This mode of operation requires electrode switching. We discuss an electrode-switching solution for multi-electrode probes, based on Complementary Metal-Oxide-Semiconductor (CMOS) multiplexors. In this solution, electrodes can be individually activated in any order, sequence or time frame through digital software commands. We discuss constraints of CMOS-based multilayer electrochemical probes during cyclic voltammetry.
Marine sediments with rapid oxic/anoxic transitions are difficult to monitor in real time. Organic overload that may lead to anoxia and buildup of hydrogen sulfide can be caused by a variety of ...factors such as sewage spills, harbor water stagnation, algal blooms and the vicinity of aquaculture operations. We have tested a novel multiprobe technology (named SPEAR) on marine sediments to evaluate its performance in monitoring sediments and overlaying water. Our results show the ability of the SPEAR probes to distinguish electrochemical changes at 2-3 mm scale and at hourly cycles. SPEAR probes have the ability to identify redox interfaces and redox transition zones in sediments, but do not use micromanipulators (which are cumbersome in field and underwater applications). We propose that the best target habitats for SPEAR-type monitoring are rapidly evolving muddy deposits and sediments near aquaculture operations where pollution with organics stresses the ecosystem.
Review of wave energy harvesters Poenaru, V.; Scurtu, I.C.; Dumitrache, C. L. ...
Journal of physics. Conference series,
09/2019, Letnik:
1297, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Nowadays modern technologies are harvesting wave energy in various and ingenious ways using latest techniques and technologies. Wave, tides and currents form a natural part of abundantly available ...energy which can be harnessed as a substitute for oil & coal to meet our energy demands. This paper will present actual harvesters and practices to obtain energy from sea.
The interrelations and sequencing of interleukins are complex (inter)actions where each interleukin can stimulate the secretion of its preceding interleukin. In this paper, we attempt to summarize ...the currently known roles of IL-4, IL-13, IL-31, and IL-33 from a multi-disciplinary perspective. In order to conduct a comprehensive review of the current literature, a search was conducted using PubMed, Google Scholar, Medscape, UpToDate, and Key Elsevier for keywords. The results were compiled from case reports, case series, letters, and literature review papers, and analyzed by a panel of multi-disciplinary specialist physicians for relevance. Based on 173 results, we compiled the following review of interleukin signaling and its clinical significance across a multitude of medical specialties. Interleukins are at the bed rock of a multitude of pathologies across different organ systems and understanding their role will likely lead to novel treatments and better outcomes for our patients. New interleukins are being described, and the role of this inflammatory cascade is still coming to light. We hope this multi-discipline review on the role interleukins play in current pathology assists in this scope.
HIDRADENITIS SUPPURATIVA IN POSTMENOPAUSE Cucu, C I; Giurcaneanu, C; Mihai, M M ...
Acta endocrinologica (Bucharest, Romania : 2005),
04/2021, Letnik:
17, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Hidradenitis suppurativa (HS) is a chronic, debilitating disease with a profound impact on the quality of life of patients.
To describe a rare case of HS with postmenopausal onset, to review the ...literature data regarding late onset HS and to discuss the current knowledge on the role of endocrine abnormalities in the development of HS.
We report the case of a 68-year-old patient in whom HS occurred 10 years after menopause. She was referred to our clinic for the presence of an open fistula on the left groin, fibrotic scars and visible alteration of the vulvar anatomy due to numerous surgical interventions. The patient shared features of the metabolic syndrome (obesity, arterial hypertension, dyslipidemia, aortic atherosclerosis), but showed no signs of virilism and no hormonal abnormality. HS was controlled using antiseptics, topical retinoids and antibiotics.
This case is of particular interest given the late onset of HS, long time after menopause. The development of HS requires a complex interaction between genetic predisposing factors, endocrine dysregulation, metabolic alterations, bacterial overgrowth and an aberrant inflammatory response. Evidence points to an important role of sex-hormones in the emergence and progression of the disease, but the underlying mechanisms are still unclear. A better understanding of HS pathogenesis is needed to elucidate the precise way in which endocrine factors influence the disease onset and course. This would guide the way to novel therapies and a better control of this challenging disease.
This paper brings to the fore, the construction of a remote controlled naval platform, without crew on board, and its possibilities to transmit or record data in inaccessible areas or in marine areas ...in which human life would be endangered. Although these unmanned platforms are not a novelty, they being used mostly for military, the solution presented is a Romanian premiere, similar to international standards, but at much lower cost, with the advantage that certain environmental action is totally insignificant. It was presented only a range of applications (video data, forecasts and submarines), the platform built in the "Mircea cel Batran" Naval Academy, allowing many improvements based on equipment that can be mounted on board.
The aim of this work is to describe the development and implementation of an experimental setup able to reproduce some characteristics of the Martian atmosphere. The development of such setup fits ...into the context of MicroMED project, that foresees the development of an optical particle counter to be accommodated on the ExoMars 2020 Surface Platform, as part of the suite of sensors named Dust Complex. MicroMED will perform the first direct measurement of the size distribution of the powder close to Martian surface. The experimental setup is able to reproduce the characteristics of the Martian atmosphere: pressure, atmospheric composition, the actual temperature in which MicroMED will operate (from −20 °C to 40 °C) and the most important thing: the presence of suspended dust.
The main result obtained in this work was the right configuration of an experimental setup in which to test sensors or instruments that work in Martian conditions. In particular, a dust injection system has been developed in order to obtain a dust distribution that was localized and without the formation of particles aggregates, for a correct calibration of the instrument.
•Having developed an experimental setup capable of reproducing some Martian weather conditions like atmospheric composition, presence of dust and pressure.•Having developed a functional powder injection system for the calibration of a Martian optical particle counter.•Use of ethanol to minimize the triboelectric effects of the grains injected into the simulation chamber and consequently to have drastically reduced the formation of dust aggregates.•Possibility of injecting powder in different ways according to the needs.•Tests on the first breadboard version of an optical particles counter capable of operating in Martian weather conditions.
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