Detection of the organic matter on Mars is one of the main goals of the future Martian landing missions. Yet, the degradation of organic molecules by cosmic ray irradiation on Mars is often ignored. ...We calculate the radiation dose accumulation rates from solar and galactic cosmic rays at various depths in the shallow Martian subsurface. We demonstrate that a 1‐billion‐year outcrop on Mars accumulates the dosage of ∼500 MGy in the top 0–2 cm and ∼50 MGy at 5–10 cm depths. We show that the preservation of ancient complex organic molecules in the shallow (∼10 cm depth) subsurface of rocks could be highly problematic if the exposure age of a geologic outcrop would exceed 300 Myr. We demonstrate that more simple organic molecules with masses ∼100 amu should have a good chance to survive in the shallow subsurface of rocks. Implications to the sampling strategy for the oncoming Martian missions are discussed.
Key Points
Cosmic rays is a key factor for the degradation of organic molecules on Mars
Solar CR are critically important for degradation in the top 2 cm of rocks
Only 100 amu organic compounds have a good chance to survive cosmic ray exposure
Studies bridging neuroscience and immunology have identified neural pathways that regulate immunity and inflammation. Recent research using methodological advances in molecular genetics has improved ...our understanding of the neural control of immunity. Here we outline mechanistic insights, focusing on translational relevance and conceptual developments. We also summarize findings from recent clinical studies of bioelectronic neuromodulation in inflammatory and autoimmune diseases.
Active research at the frontiers of immunology and neuroscience has identified multiple points of interaction and communication between the immune system and the nervous system. Immune cell ...activation stimulates neuronal circuits that regulate innate and adaptive immunity. Molecular mechanistic insights into the inflammatory reflex and other neuro-immune interactions have greatly advanced our understanding of immunity and identified new therapeutic possibilities in inflammatory and autoimmune diseases. Recent successful clinical trials using bioelectronic devices that modulate the inflammatory reflex to significantly ameliorate rheumatoid arthritis and inflammatory bowel disease provide a path for using electrons as a therapeutic modality for targeting molecular mechanisms of immunity. Here, we review mechanisms of peripheral sensory neuronal function in response to immune challenges, the neural regulation of immunity and inflammation, and the therapeutic implications of those mechanistic insights.
In this review Chavan, Pavlov, and Tracey discuss mechanisms at the interface of the immune system and the nervous system as well as the role of neural pathways in the regulation of immunity. They also summarize the therapeutic implications of neuromodulation in animal models and clinical settings of inflammatory and autoimmune disease.
The nervous system regulates immunity and inflammation. The molecular detection of pathogen fragments, cytokines, and other immune molecules by sensory neurons generates immunoregulatory responses ...through efferent autonomic neuron signaling. The functional organization of this neural control is based on principles of reflex regulation. Reflexes involving the vagus nerve and other nerves have been therapeutically explored in models of inflammatory and autoimmune conditions, and recently in clinical settings. The brain integrates neuro-immune communication, and brain function is altered in diseases characterized by peripheral immune dysregulation and inflammation. Here we review the anatomical and molecular basis of the neural interface with immunity, focusing on peripheral neural control of immune functions and the role of the brain in the model of the immunological homunculus. Clinical advances stemming from this knowledge within the framework of bioelectronic medicine are also briefly outlined.
The vagus nerve has an important role in regulation of metabolic homeostasis, and efferent vagus nerve-mediated cholinergic signalling controls immune function and proinflammatory responses via the ...inflammatory reflex. Dysregulation of metabolism and immune function in obesity are associated with chronic inflammation, a critical step in the pathogenesis of insulin resistance and type 2 diabetes mellitus. Cholinergic mechanisms within the inflammatory reflex have, in the past 2 years, been implicated in attenuating obesity-related inflammation and metabolic complications. This knowledge has led to the exploration of novel therapeutic approaches in the treatment of obesity-related disorders.
The paper proposes a multiresolution cross-correlation analysis (MCCA) combining cross-correlation analysis of complex signals with multiresolution wavelet analysis, which provides decomposition of ...datasets at several resolution levels and processing of the obtained sets of detail wavelet coefficients. Such an approach can improve the interpretation of changes in the dynamics of the system under study, associating the occurring phenomena with the mechanisms responsible for them. The possibilities of MCCA are illustrated by the example of synchronous and asynchronous dynamics of the model of two interacting nephrons providing oscillations with two different time scales.
Specific features of using luminescent sensors with transducers based on a sensitive layer containing quantum dots immobilized in polymer matrixes of some fluorinated copolymers are described. ...Features of the formation of an analytical signal in time are studied. It is found that, in the analysis of some iodinated organic compounds, damped fluctuations of the luminescence intensity of the sensitive layer around a steady-state value can occur. Modern ideas of nonlinear and wave diffusion in polymer layers are attracted to explain the observed effects. Study of the kinetics of sorption by an independent method confirmed the fluctuations of sorption near its equilibrium value. The results obtained were used for the development of luminescent sensors based on quantum dots.
The Maxwell–Stefan diffusion equations for multicomponent neutral gas mixtures with thermodiffusion ratios and diffusion correction factors in the Chapman–Cowling third-order approximation are ...derived. These thermodiffusion ratios and diffusion correction factors are presented explicitly as functions of masses, number densities, thermal conductivities, and the Chapman–Cowling collision integrals of the neutral species under consideration. Applications to the multicomponent mixture of atmospheric neutral gases O, N
2
, O
2
, He, H, Ar, H
2
, N, and NO are considered, and recommendations are given for using the results of this paper in studies of the Earth's atmosphere.
We give sufficient conditions for regularizing a distribution of the form
, where
is a distribution holomorphic in the parameter
, while
is an infinitely differentiable function of
outside some ...closed set
with power singularities of derivatives on
and holomorphic in
.
Improved understanding of neuroimmune communication and the neural regulation of immunity and inflammation has recently led to proposing the concept of the "neuroimmune communicatome." This advance ...is based on experimental evidence for an organized and brain-integrated reflex-like relationship and dialogue between the nervous and the immune systems. A key circuitry in this communicatome is provided by efferent vagus nerve fibers and cholinergic signaling. Inflammation and metabolic alterations coexist in many disorders affecting the liver and the gastrointestinal (GI) tract, including obesity, metabolic syndrome, fatty liver disease, liver injury, and liver failure, as well as inflammatory bowel disease. Here, we outline mechanistic insights regarding the role of the vagus nerve and cholinergic signaling in the regulation of inflammation linked to metabolic derangements and the pathogenesis of these disorders in preclinical settings. Recent clinical advances using this knowledge in novel therapeutic neuromodulatory approaches within the field of bioelectronic medicine are also briefly summarized.
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