Anomalous Behavior of the $$E_{u}^{1}$$ Infrared-active Phonon Mode in Bi2 – xSrxSe3 Crystal

Bridge health monitoring is increasingly relevant for the maintenance of existing structures or new structures with innovative concepts that require validation of design predictions. In the United States there are more than 600,000 highway bridges. Nearly half of them (46.4%) are rated as fair while about 1 out of 13 (7.6%) is rated in poor condition. As such, the United States is one of those countries in which bridge health monitoring systems are installed in order to complement conventional periodic nondestructive inspections. This paper reviews the challenges associated with bridge health monitoring related to the detection of specific bridge characteristics that may be indicators of anomalous behavior. The methods used to detect loss of stiffness, time-dependent and temperature-dependent deformations, fatigue, corrosion, and scour are discussed. Owing to the extent of the existing scientific literature, this review focuses on systems installed in U.S. bridges over the last 20 years. These are all major factors that contribute to long-term degradation of bridges. Issues related to wireless sensor drifts are discussed as well. The scope of the paper is to help newcomers, practitioners, and researchers at navigating the many methodologies that have been proposed and developed in order to identify damage using data collected from sensors installed in real structures.

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Electrochemical Biosensors for Cytokine Profiling: Recent Advancements and Possibilities in the Near Future

Biosensors ◽

10.3390/bios11030094 ◽

2021 ◽

Vol 11 (3) ◽

pp. 94

Author(s):

Nirmita Dutta ◽

Peter B. Lillehoj ◽

Pedro Estrela ◽

Gorachand Dutta

Keyword(s):

Immune System ◽

Cost Effective ◽

Anomalous Behavior ◽

Quantitative Detection ◽

Electrochemical Biosensors ◽

Aberrant Expression ◽

Detection Techniques ◽

Short Period ◽

User Friendly ◽

Cytokine Profiling

Cytokines are soluble proteins secreted by immune cells that act as molecular messengers relaying instructions and mediating various functions performed by the cellular counterparts of the immune system, by means of a synchronized cascade of signaling pathways. Aberrant expression of cytokines can be indicative of anomalous behavior of the immunoregulatory system, as seen in various illnesses and conditions, such as cancer, autoimmunity, neurodegeneration and other physiological disorders. Cancer and autoimmune diseases are particularly adept at developing mechanisms to escape and modulate the immune system checkpoints, reflected by an altered cytokine profile. Cytokine profiling can provide valuable information for diagnosing such diseases and monitoring their progression, as well as assessing the efficacy of immunotherapeutic regiments. Toward this goal, there has been immense interest in the development of ultrasensitive quantitative detection techniques for cytokines, which involves technologies from various scientific disciplines, such as immunology, electrochemistry, photometry, nanotechnology and electronics. This review focusses on one aspect of this collective effort: electrochemical biosensors. Among the various types of biosensors available, electrochemical biosensors are one of the most reliable, user-friendly, easy to manufacture, cost-effective and versatile technologies that can yield results within a short period of time, making it extremely promising for routine clinical testing.

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Tight-binding investigation of the structural and vibrational properties of graphene–single wall carbon nanotube junctions

Nanoscale Advances ◽

10.1039/d0na00881h ◽

2021 ◽

Author(s):

Juhi Srivastava ◽

Anshu Gaur

Keyword(s):

Charge Transfer ◽

Carbon Nanotube ◽

Phonon Mode ◽

Tight Binding ◽

Hybrid Nanostructures ◽

Structural Deformation ◽

Vibrational Properties ◽

Single Wall Carbon Nanotube ◽

Single Wall Carbon ◽

Carbon Nanotube Junctions

The phonon mode frequencies of SWNT and SLG in hybrid nanostructures are sensitive to various interactions, such as vdW forces, structural deformation and/or charge transfer between SWNT and SLG.

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Transvection and Silencing of the Scr Homeotic Gene of Drosophila melanogaster

Genetics ◽

10.1093/genetics/161.2.733 ◽

2002 ◽

Vol 161 (2) ◽

pp. 733-746

Author(s):

Jeffrey W Southworth ◽

James A Kennison

Keyword(s):

Drosophila Melanogaster ◽

Chromosomal Aberrations ◽

Regulatory Element ◽

Regulatory Elements ◽

Anomalous Behavior ◽

Polycomb Group ◽

Homeotic Gene ◽

Polycomb Group Proteins ◽

Sex Combs Reduced ◽

In Cis

Abstract The Sex combs reduced (Scr) gene specifies the identities of the labial and first thoracic segments in Drosophila melanogaster. In imaginal cells, some Scr mutations allow cis-regulatory elements on one chromosome to stimulate expression of the promoter on the homolog, a phenomenon that was named transvection by Ed Lewis in 1954. Transvection at the Scr gene is blocked by rearrangements that disrupt pairing, but is zeste independent. Silencing of the Scr gene in the second and third thoracic segments, which requires the Polycomb group proteins, is disrupted by most chromosomal aberrations within the Scr gene. Some chromosomal aberrations completely derepress Scr even in the presence of normal levels of all Polycomb group proteins. On the basis of the pattern of chromosomal aberrations that disrupt Scr gene silencing, we propose a model in which two cis-regulatory elements interact to stabilize silencing of any promoter or cis-regulatory element physically between them. This model also explains the anomalous behavior of the Scx allele of the flanking homeotic gene, Antennapedia. This allele, which is associated with an insertion near the Antennapedia P1 promoter, inactivates the Antennapedia P1 and P2 promoters in cis and derepresses the Scr promoters both in cis and on the homologous chromosome.

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Submillimeter Spectroscopy of To-Phonon Mode Softening in PbTe

1976 International Conference on Submillimeter Waves and Their Applications ◽

10.1109/icswa.1976.9350051 ◽

1976 ◽

Author(s):

G. Bauer ◽

H. Burkhard ◽

A. Lopez-Otero

Keyword(s):

Phonon Mode ◽

Mode Softening ◽

Submillimeter Spectroscopy

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A Low-Cost Jamming Detection Approach Using Performance Metrics in Cluster-Based Wireless Sensor Networks

Sensors ◽

10.3390/s21041179 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1179

Author(s):

Carolina Del-Valle-Soto ◽

Carlos Mex-Perera ◽

Juan Arturo Nolazco-Flores ◽

Alma Rodríguez ◽

Julio C. Rosas-Caro ◽

...

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

Routing Protocol ◽

Performance Metrics ◽

Low Cost ◽

Detection Algorithm ◽

Anomalous Behavior ◽

Wireless Sensor ◽

Jamming Detection ◽

Minimal Energy Expenditure

Wireless Sensor Networks constitute an important part of the Internet of Things, and in a similar way to other wireless technologies, seek competitiveness concerning savings in energy consumption and information availability. These devices (sensors) are typically battery operated and distributed throughout a scenario of particular interest. However, they are prone to interference attacks which we know as jamming. The detection of anomalous behavior in the network is a subject of study where the routing protocol and the nodes increase power consumption, which is detrimental to the network’s performance. In this work, a simple jamming detection algorithm is proposed based on an exhaustive study of performance metrics related to the routing protocol and a significant impact on node energy. With this approach, the proposed algorithm detects areas of affected nodes with minimal energy expenditure. Detection is evaluated for four known cluster-based protocols: PEGASIS, TEEN, LEACH, and HPAR. The experiments analyze the protocols’ performance through the metrics chosen for a jamming detection algorithm. Finally, we conducted real experimentation with the best performing wireless protocols currently used, such as Zigbee and LoRa.

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