Olfactory Sensing and Navigation in Turbulent Environments

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Gautam Reddy ◽  
Venkatesh N. Murthy ◽  
Massimo Vergassola
Keyword(s):  
Turbulent Flows ◽  
Molecular Diffusion ◽  
Turbulent Transport ◽  
Annual Review ◽  
Publication Date ◽  
Pheromone Communication ◽  
Fluid Turbulence ◽  
Turbulent Environments ◽  
Future Challenges ◽  
Olfactory Organs

Fluid turbulence is a double-edged sword for the navigation of macroscopic animals, such as birds, insects, and rodents. On one hand, turbulence enables pheromone communication among mates and the possibility of locating food by their odors from long distances. Molecular diffusion would indeed be unable to spread odors over relevant distances in natural conditions. On the other hand, turbulent flows are hard to predict, and learning effective maneuvers to navigate them is challenging, as we discuss in this review. We first provide a summary of the olfactory organs that sense airborne or surface-bound odors, as well as the computational tasks that animals face when extracting information useful for navigation from an olfactory signal. A compendium of the dynamics of turbulent transport emphasizes those aspects that directly impact animals’ behavior. The state of the art on navigational strategies is discussed, followed by a concluding section dedicated to future challenges in the field. Expected final online publication date for the Annual Review of Condensed Matter Physics, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Sepsis-Induced Immunosuppression

2021 ◽  
Vol 84 (1) ◽  
Author(s):  
Lisa K. Torres ◽  
Peter Pickkers ◽  
Tom van der Poll
Keyword(s):  
Organ Transplant ◽  
Annual Review ◽  
Publication Date ◽  
Predisposing Factor ◽  
Substantial Impact ◽  
Immunomodulatory Agents ◽  
Secondary Infections ◽  
Future Challenges ◽  
Treatment Paradigm ◽  
New Treatment

Sepsis is expected to have a substantial impact on public health and cost as its prevalence increases. Factors contributing to increased prevalence include a progressively aging population, advances in the use of immunomodulatory agents to treat a rising number of diseases, and immune-suppressing therapies in organ transplant recipients and cancer patients. It is now recognized that sepsis is associated with profound and sustained immunosuppression, which has been implicated as a predisposing factor in the increased susceptibility of patients to secondary infections and mortality. In this review, we discuss mechanisms of sepsis-induced immunosuppression and biomarkers that identify a state of impaired immunity. We also highlight immune-enhancing strategies that have been evaluated in patients with sepsis, as well as therapeutics under current investigation. Finally, we describe future challenges and the need for a new treatment paradigm, integrating predictive enrichment with patient factors that may guide the future selection of tailored immunotherapy. Expected final online publication date for the Annual Review of Physiology, Volume 84 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals Physiologically Based Modeling of Food Digestion and Intestinal Microbiota: State of the Art and Future Challenges. An INFOGEST Review

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Steven Le Feunteun ◽  
Ahmed Al-Razaz ◽  
Matthijs Dekker ◽  
Erwin George ◽  
Beatrice Laroche ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Historical Background ◽  
Annual Review ◽  
Publication Date ◽  
Physiologically Based ◽  
The Future ◽  
Future Challenges ◽  
Full Picture ◽  
Food Digestion

This review focuses on modeling methodologies of the gastrointestinal tract during digestion that have adopted a systems-view approach and, more particularly, on physiologically based compartmental models of food digestion and host–diet–microbiota interactions. This type of modeling appears very promising for integrating the complex stream of mechanisms that must be considered and retrieving a full picture of the digestion process from mouth to colon. We may expect these approaches to become more and more accurate in the future and to serve as a useful means of understanding the physicochemical processes occurring in the gastrointestinal tract, interpreting postprandial in vivo data, making relevant predictions, and designing healthier foods. This review intends to provide a scientific and historical background of this field of research, before discussing the future challenges and potential benefits of the establishment of such a model to study and predict food digestion and absorption in humans. Expected final online publication date for the Annual Review of Food Science and Technology, Volume 12 is March 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

The Making of Plant Armor: The Periderm

2022 ◽  
Vol 73 (1) ◽  
Author(s):  
Olga Serra ◽  
Ari Pekka Mähönen ◽  
Alexander J. Hetherington ◽  
Laura Ragni
Keyword(s):  
Regulatory Networks ◽  
Plant Biology ◽  
Raw Material ◽  
Industrial Processes ◽  
Annual Review ◽  
Publication Date ◽  
Biotic And Abiotic Stress ◽  
Meristematic Tissue ◽  
Future Challenges ◽  
Periderm Formation

The periderm acts as armor protecting the plant's inner tissues from biotic and abiotic stress. It forms during the radial thickening of plant organs such as stems and roots and replaces the function of primary protective tissues such as the epidermis and the endodermis. A wound periderm also forms to heal and protect injured tissues. The periderm comprises a meristematic tissue called the phellogen, or cork cambium, and its derivatives: the lignosuberized phellem and the phelloderm. Research on the periderm has mainly focused on the chemical composition of the phellem due to its relevance as a raw material for industrial processes. Today, there is increasing interest in the regulatory network underlying periderm development as a novel breeding trait to improve plant resilience and to sequester CO2. Here, we discuss our current understanding of periderm formation, focusing on aspects of periderm evolution, mechanisms of periderm ontogenesis, regulatory networks underlying phellogen initiation and cork differentiation, and future challenges of periderm research. Expected final online publication date for the Annual Review of Plant Biology, Volume 73 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Genetics of Shoot Meristem and Shoot Regeneration

2021 ◽  
Vol 55 (1) ◽  
Author(s):  
Leor Eshed Williams
Keyword(s):  
Shoot Regeneration ◽  
Developmental Plasticity ◽  
Genetic Network ◽  
Shoot Meristem ◽  
Annual Review ◽  
Publication Date ◽  
Cell Specification ◽  
Future Challenges ◽  
Gene Regulatory ◽  
Stochastic Events

Plants exhibit remarkable lineage plasticity, allowing them to regenerate organs that differ from their respective origins. Such developmental plasticity is dependent on the activity of pluripotent founder cells or stem cells residing in meristems. At the shoot apical meristem (SAM), the constant flow of cells requires continuing cell specification governed by a complex genetic network, with the WUSCHEL transcription factor and phytohormone cytokinin at its core. In this review, I discuss some intriguing recent discoveries that expose new principles and mechanisms of patterning and cell specification acting both at the SAM and, prior to meristem organogenesis during shoot regeneration. I also highlight unanswered questions and future challenges in the study of SAM and meristem regeneration. Finally, I put forward a model describing stochastic events mediated by epigenetic factors to explain how the gene regulatory network might be initiated at the onset of shoot regeneration. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals Russell Donnelly and His Leaks

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
J.J. Niemela ◽  
K.R. Sreenivasan
Keyword(s):  
Music History ◽  
Art Music ◽  
Annual Review ◽  
Publication Date ◽  
Yale University ◽  
Scholarly Journals ◽  
Fluid Turbulence ◽  
Scientific Meetings ◽  
S Chandrasekhar ◽  
The University

Russell James Donnelly (b. 1930) was an exceptionally creative physicist with many other interests: art, music, history, and scientific societies and their scholarly journals. He reinvigorated the maturing field of low temperature physics by linking it strongly to fluid turbulence by bold and optimistic leadership at the intersection of the two fields. Immediately after achieving his Ph.D. at Yale University with C.T. Lane and L. Onsager, Russ joined the University of Chicago in 1956, where he became a professor at the first possible opportunity. After some ten years at U. Chicago, where he worked for a time with S. Chandrasekhar, he moved to the University of Oregon and led a vigorous life until his death in 2015. Russ was an excellent organizer of scientific meetings and an enthusiastic expositor of his science. He had a profound sense of service to the community, both civic and scientific, and showed exceptional scientific openness and generosity to his colleagues. He was greatly admired by his community. Expected final online publication date for the Annual Review of Condensed Matter Physics, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Estimating DSGE Models: Recent Advances and Future Challenges

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Jesús Fernández-Villaverde ◽  
Pablo A. Guerrón-Quintana
Keyword(s):  
Likelihood Function ◽  
Space Representation ◽  
Annual Review ◽  
Publication Date ◽  
Dsge Models ◽  
State Space Representation ◽  
Current State ◽  
Recent Advances ◽  
Future Challenges ◽  
Dynamic Stochastic

We review the current state of the estimation of dynamic stochastic general equilibrium (DSGE) models. After introducing a general framework for dealing with DSGE models, the state-space representation, we discuss how to evaluate moments or the likelihood function implied by such a structure. We discuss, in varying degrees of detail, recent advances in the field, such as the tempered particle filter, approximated Bayesian computation, Hamiltonian Monte Carlo, variational inference, and machine learning. These methods show much promise but have not been fully explored by the DSGE community yet. We conclude by outlining three future challenges for this line of research. Expected final online publication date for the Annual Review of Economics, Volume 13 is August 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Flow and Drop Transport Along Liquid-Infused Surfaces

2021 ◽  
Vol 54 (1) ◽  
Author(s):  
Steffen Hardt ◽  
Glen McHale
Keyword(s):  
Flow Field ◽  
Fluid Mechanics ◽  
Drag Reduction ◽  
Turbulent Flows ◽  
Slip Length ◽  
Lubricant Layer ◽  
Annual Review ◽  
Publication Date ◽  
Self Healing ◽  
Effective Slip Length

Liquid-infused surfaces (LISs) are composite solid–liquid surfaces with remarkable features such as liquid repellency, self-healing, and the suppression of fouling. This review focuses on the fluid mechanics on LISs, that is, the interaction of surfaces with a flow field and the behavior of drops on such surfaces. LISs can be characterized by an effective slip length that is closely related to their drag reduction property, which makes them suitable for several applications, especially for turbulent flows. Drag reduction, however, is compromised by failure mechanisms such as the drainage of lubricant from surface textures. The flow field can also sculpt the lubricant layer in a coupled self-organization process. For drops, the lubricant reduces drop pinning and increases drop mobility, but also results in a wetting ridge and the associated concept of an apparent contact angle. Design of LIS wettability and topography can induce low-friction drop motion, and drops can dynamically shape the lubricant ridges and film thickness. Expected final online publication date for the Annual Review of Fluid Mechanics, Volume 54 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Endogenous Retroviruses Drive Resistance and Promotion of Exogenous Retroviral Homologs

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Elliott S. Chiu ◽  
Sue VandeWoude
Keyword(s):  
Immune Modulation ◽  
Viral Infections ◽  
Viral Evolution ◽  
Endogenous Retroviruses ◽  
Annual Review ◽  
Publication Date ◽  
Biological Functions ◽  
Self Tolerance ◽  
Vertebrate Hosts ◽  
Insight Into

Endogenous retroviruses (ERVs) serve as markers of ancient viral infections and provide invaluable insight into host and viral evolution. ERVs have been exapted to assist in performing basic biological functions, including placentation, immune modulation, and oncogenesis. A subset of ERVs share high nucleotide similarity to circulating horizontally transmitted exogenous retrovirus (XRV) progenitors. In these cases, ERV–XRV interactions have been documented and include ( a) recombination to result in ERV–XRV chimeras, ( b) ERV induction of immune self-tolerance to XRV antigens, ( c) ERV antigen interference with XRV receptor binding, and ( d) interactions resulting in both enhancement and restriction of XRV infections. Whereas the mechanisms governing recombination and immune self-tolerance have been partially determined, enhancement and restriction of XRV infection are virus specific and only partially understood. This review summarizes interactions between six unique ERV–XRV pairs, highlighting important ERV biological functions and potential evolutionary histories in vertebrate hosts. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 9 is February 16, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Experiments on Flame Flashback in a Quasi-2D Turbulent Wall Boundary Layer for Premixed Methane-Hydrogen-Air Mixtures

2010 ◽  
Author(s):  
Christian Eichler ◽  
Thomas Sattelmayer
Keyword(s):  
Boundary Layer ◽  
Boundary Layers ◽  
Turbulent Flows ◽  
Turbulent Transport ◽  
Wall Friction ◽  
Evaluation Procedure ◽  
Wall Boundary Layer ◽  
Wall Boundary ◽  
Flame Flashback ◽  
Turbulent Wall

Premixed combustion of hydrogen-rich mixtures involves the risk of flame flashback through wall boundary layers. For laminar flow conditions, the flashback mechanism is well understood and is usually correlated by a critical velocity gradient at the wall. Turbulent transport inside the boundary layer considerably increases the flashback propensity. Only tube burner setups have been investigated in the past and thus turbulent flashback limits were only derived for a fully-developed Blasius wall friction profile. For turbulent flows, details of the flame propagation in proximity to the wall remain unclear. This paper presents results from a new experimental combustion rig, apt for detailed optical investigations of flame flashbacks in a turbulent wall boundary layer developing on a flat plate and being subject to an adjustable pressure gradient. Turbulent flashback limits are derived from the observed flame position inside the measurement section. The fuels investigated cover mixtures of methane, hydrogen and air at various mixing ratios. The associated wall friction distributions are determined by RANS computations of the flow inside the measurement section with fully resolved boundary layers. Consequently, the interaction between flame back pressure and incoming flow is not taken into account explicitly, in accordance with the evaluation procedure used for tube burner experiments. The results are compared to literature values and the critical gradient concept is reviewed in light of the new data.

Advancing Socioeconomic Rights Through Interdisciplinary Factfinding: Opportunities and Challenges

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Sarah Knuckey ◽  
Joshua D. Fisher ◽  
Amanda M. Klasing ◽  
Tess Russo ◽  
Margaret L. Satterthwaite
Keyword(s):  
Human Rights ◽  
Mixed Methods ◽  
Social Science ◽  
Science Volume ◽  
Lessons Learned ◽  
Limited Resources ◽  
Annual Review ◽  
Publication Date ◽  
Socioeconomic Rights ◽  
Human Rights Movement

The human rights movement is increasingly using interdisciplinary, multidisciplinary, mixed-methods, and quantitative factfinding. There has been too little analysis of these shifts. This article examines some of the opportunities and challenges of these methods, focusing on the investigation of socioeconomic human rights. By potentially expanding the amount and types of evidence available, factfinding's accuracy and persuasiveness can be strengthened, bolstering rights claims. However, such methods can also present significant challenges and may pose risks in individual cases and to the human rights movement generally. Interdisciplinary methods can be costly in human, financial, and technical resources; are sometimes challenging to implement; may divert limited resources from other work; can reify inequalities; may produce “expertise” that disempowers rightsholders; and could raise investigation standards to an infeasible or counterproductive level. This article includes lessons learned and questions to guide researchers and human rights advocates considering mixed-methods human rights factfinding. Expected final online publication date for the Annual Review of Law and Social Science, Volume 17 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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