scholarly journals A mouse bio-electronic nose for sensitive and versatile chemical detection

2020 ◽  
Author(s):  
Erez Shor ◽  
Pedro Herrero-Vidal ◽  
Adam Dewan ◽  
Ilke Uguz ◽  
Vincenzo F. Curto ◽  
...  
Keyword(s):  
Electronic Nose ◽  
Early Stage ◽  
Wide Spectrum ◽  
Electrode Array ◽  
Machine Learning Techniques ◽  
Detection Methods ◽  
Chemical Detection ◽  
Specific Chemical ◽  
Volatile Chemicals ◽  
Wide Range

AbstractWhen it comes to simultaneous versatility, speed, and specificity in detecting volatile chemicals, biological olfactory systems far outperform all artificial chemical detection devices. Consequently, the use of trained animals for chemical detection in security, defense, healthcare, agriculture, and other applications has grown astronomically. However, the use of animals in this capacity requires extensive training and behavior-based communication. Here we propose an alternative strategy, a bio-electronic nose, that capitalizes on the superior capability of the mammalian olfactory system, but bypasses behavioral output by reading olfactory information directly from the brain. We engineered a brain-machine interface that captures neuronal signals from an early stage of olfactory processing in awake mice, and used machine learning techniques to form a sensitive and selective chemical detector. We chronically implanted a grid electrode array on the surface of the mouse olfactory bulb and systematically recorded responses to a large battery of odorants and odorant mixtures across a wide range of concentrations. The bio-electronic nose has a comparable sensitivity to the trained animal and can detect odors on a variable background. We also introduce a novel genetic engineering approach designed to improve the sensitivity of our bio-electronic nose for specific chemical targets. Our bio-electronic nose outperforms current detection methods and unlocks a wide spectrum of civil, medical and environmental applications.

scholarly journals Proximal Methods for Plant Stress Detection Using Optical Sensors and Machine Learning

Biosensors ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 193
Author(s):  
Alanna V. Zubler ◽  
Jeong-Yeol Yoon
Keyword(s):  
Machine Learning ◽  
Optical Sensors ◽  
Near Infrared ◽  
Plant Stress ◽  
Machine Learning Algorithms ◽  
Machine Learning Techniques ◽  
Detection Methods ◽  
Stress Detection ◽  
Recent Advances ◽  
Wide Range

Plant stresses have been monitored using the imaging or spectrometry of plant leaves in the visible (red-green-blue or RGB), near-infrared (NIR), infrared (IR), and ultraviolet (UV) wavebands, often augmented by fluorescence imaging or fluorescence spectrometry. Imaging at multiple specific wavelengths (multi-spectral imaging) or across a wide range of wavelengths (hyperspectral imaging) can provide exceptional information on plant stress and subsequent diseases. Digital cameras, thermal cameras, and optical filters have become available at a low cost in recent years, while hyperspectral cameras have become increasingly more compact and portable. Furthermore, smartphone cameras have dramatically improved in quality, making them a viable option for rapid, on-site stress detection. Due to these developments in imaging technology, plant stresses can be monitored more easily using handheld and field-deployable methods. Recent advances in machine learning algorithms have allowed for images and spectra to be analyzed and classified in a fully automated and reproducible manner, without the need for complicated image or spectrum analysis methods. This review will highlight recent advances in portable (including smartphone-based) detection methods for biotic and abiotic stresses, discuss data processing and machine learning techniques that can produce results for stress identification and classification, and suggest future directions towards the successful translation of these methods into practical use.

scholarly journals Advances in Electrochemical Impedance Spectroscopy Detection of Endocrine Disruptors

Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6443
Author(s):  
Lucian-Gabriel Zamfir ◽  
Mihaela Puiu ◽  
Camelia Bala
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Endocrine Disruptors ◽  
Electrochemical Impedance ◽  
Early Stage ◽  
Endocrine System ◽  
Detection Methods ◽  
Enzyme Linked Immunosorbent Assay ◽  
Portable Devices ◽  
Wide Range

Endocrine disruptors (EDs) are contaminants that may mimic or interfere with the body’s hormones, hampering the normal functions of the endocrine system in humans and animals. These substances, either natural or man-made, are involved in development, breeding, and immunity, causing a wide range of diseases and disorders. The traditional detection methods such as enzyme linked immunosorbent assay (ELISA) and chromatography are still the golden techniques for EDs detection due to their high sensitivity, robustness, and accuracy. Nevertheless, they have the disadvantage of being expensive and time-consuming, requiring bulky equipment or skilled personnel. On the other hand, early stage detection of EDs on-the-field requires portable devices fulfilling the Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment free, Deliverable to end users (ASSURED) norms. Electrochemical impedance spectroscopy (EIS)-based sensors can be easily implemented in fully automated, sample-to-answer devices by integrating electrodes in microfluidic chips. The latest achievements on EIS-based sensors are discussed and critically assessed.

scholarly journals Pediatric Sepsis: Clinical Markers

2017 ◽  
Vol 07 (01) ◽  
pp. e42-e53
Author(s):  
S. Szima ◽  
G. Balazs ◽  
N. Elek ◽  
P. Dahlem
Keyword(s):  
Early Recognition ◽  
Early Stage ◽  
Wide Spectrum ◽  
Gas Analysis ◽  
Clinical Markers ◽  
Care Providers ◽  
Early Stage Disease ◽  
Arterial Blood ◽  
Wide Range ◽  
Pediatric Sepsis

AbstractPediatric sepsis can be caused by infection agents such as viruses, bacteria, protozoa, or their toxins. Clinical features cover a remarkably wide spectrum. Early recognition of the disease and prompt initiation of therapy substantially improve mortality and the outcome of potential complications. After an initial phase of very mild symptoms, the spread of microbes or toxins in the bloodstream presents as septic shock through vasoregulatory disturbance, absolute or relative intravascular volume loss, and consequential tachycardia and hypotension. The most common accompanying symptom is fever. In physical examination, features such as altered mental status, excess respiratory effort, tachycardia, and prolonged capillary refill time are present at an early stage of the disease. Laboratory tests for the assessment of early stage severity and subsequent monitoring of treatment efficacy include point-of-care arterial blood gas analysis and lactate assay. In early stage disease, it is imperative to promptly start adequate antimicrobial and supportive treatment once bacterial cultures have been taken. Despite the availability of a wide range of laboratory and imaging tests today, diagnosis and severity assessment of sepsis still primarily rely on medical history and clinical examination. In light of this, it is possible for trained care providers to detect the early signs of a septic child during repetitive physical examinations. This is still the mainstay of diagnosis and can provide in all care settings a significant reduction in therapeutic delay; this, in turn, helps to reduce sepsis-related mortality and morbidity.

Efficient Prediction of Structural and Electronic Properties of Hybrid 2D Materials Using DFT and Machine Learning

2018 ◽  
Author(s):  
Sherif Tawfik ◽  
Olexandr Isayev ◽  
Catherine Stampfl ◽  
Joseph Shapter ◽  
David Winkler ◽  
...  
Keyword(s):  
Machine Learning ◽  
Band Gap ◽  
Density Functional ◽  
2D Materials ◽  
Van Der Waals ◽  
Building Blocks ◽  
Machine Learning Techniques ◽  
Interlayer Distance ◽  
Computational Screening ◽  
Wide Range

Materials constructed from different van der Waals two-dimensional (2D) heterostructures offer a wide range of benefits, but these systems have been little studied because of their experimental and computational complextiy, and because of the very large number of possible combinations of 2D building blocks. The simulation of the interface between two different 2D materials is computationally challenging due to the lattice mismatch problem, which sometimes necessitates the creation of very large simulation cells for performing density-functional theory (DFT) calculations. Here we use a combination of DFT, linear regression and machine learning techniques in order to rapidly determine the interlayer distance between two different 2D heterostructures that are stacked in a bilayer heterostructure, as well as the band gap of the bilayer. Our work provides an excellent proof of concept by quickly and accurately predicting a structural property (the interlayer distance) and an electronic property (the band gap) for a large number of hybrid 2D materials. This work paves the way for rapid computational screening of the vast parameter space of van der Waals heterostructures to identify new hybrid materials with useful and interesting properties.

Prostate Cancer: Biology, Incidence, Detection Methods, Treatment Methods, and Vaccines

2020 ◽  
Vol 20 (10) ◽  
pp. 847-854
Author(s):  
Ronald Bartzatt
Keyword(s):  
Prostate Cancer ◽  
Cancer Treatment ◽  
Prostate Specific Antigen ◽  
Cancer Biology ◽  
Early Stage ◽  
Specific Antigen ◽  
Detection Methods ◽  
Hormone Refractory Prostate Cancer ◽  
High Risk Prostate Cancer ◽  
Hormone Refractory

Cancer of the prostate are cancers in which most incidences are slow-growing, and in the U.S., a record of 1.2 million new cases of prostate cancer occurred in 2018. The rates of this type of cancer have been increasing in developing nations. The risk factors for prostate cancer include age, family history, and obesity. It is believed that the rate of prostate cancer is correlated with the Western diet. Various advances in methods of radiotherapy have contributed to lowering morbidity. Therapy for hormone- refractory prostate cancer is making progress, for almost all men with metastases will proceed to hormone-refractory prostate cancer. Smoking cigarettes along with the presence of prostate cancer has been shown to cause a higher risk of mortality in prostate cancer. The serious outcome of incontinence and erectile dysfunction result from the cancer treatment of surgery and radiation, particularly for prostate- specific antigen detected cancers that will not cause morbidity or mortality. Families of patients, as well as patients, are profoundly affected following the diagnosis of prostate cancer. Poor communication between spouses during prostate cancer increases the risk for poor adjustment to prostate cancer. The use of serum prostate-specific antigen to screen for prostate cancer has led to a greater detection, in its early stage, of this cancer. Prostate cancer is the most common malignancy in American men, accounting for more than 29% of all diagnosed cancers and about 13% of all cancer deaths. A shortened course of hormonal therapy with docetaxel following radical prostatectomy (or radiation therapy) for high-risk prostate cancer has been shown to be both safe and feasible. Patients treated with docetaxel-estramustine had a prostate-specific antigen response decline of at least 50%. Cancer vaccines are an immune-based cancer treatment that may provide the promise of a non-toxic but efficacious therapeutic alternative for cancer patients. Further studies will elucidate improved methods of detection and treatment.

Cucurbitacins as Anticancer Agents: A Patent Review

2019 ◽  
Vol 14 (2) ◽  
pp. 133-143 ◽  
Author(s):  
Hidayat Hussain ◽  
Ivan R. Green ◽  
Muhammad Saleem ◽  
Khanzadi F. Khattak ◽  
Muhammad Irshad ◽  
...  
Keyword(s):  
Anticancer Agents ◽  
Wide Spectrum ◽  
Biological Effects ◽  
Therapeutic Effects ◽  
Cytotoxic Effects ◽  
Natural Sources ◽  
Oh Groups ◽  
Drug Candidates ◽  
The Past ◽  
Wide Range

Background: Cucurbitacins belong to a group of tetracyclic triterpenoids that display a wide range of biological effects. In the past, numerous cucurbitacins have been isolated from natural sources and many active compounds have been synthesized using the privileged scaffold in order to enhance its cytotoxic effects. Objective: his review covers patents on the therapeutic effects of natural cucurbitacins and their synthetic analogs published during the past decade. By far, the majority of patents published are related to cancer and Structure-Activity Relationships (SAR) of these compounds are included to lend gravitas to this important class of natural products. Methods: The date about the published patents was downloaded via online open access patent databases. Results: Cucurbitacins display significant cytotoxic properties, in particular cucurbitacins B and D which possess very potent effects towards a number of cancer cells. Numerous cucurbitacins isolated from natural sources have been derivatized through chemical modification at the C(2)-OH and C(25)- OH groups. Most importantly, an acyl ester of the C(25)-OH and, iso-propyl, n-propyl and ethyl ether groups of the C(2)-OH demonstrated the most increased cytotoxic activity. Conclusion: The significant cytotoxic effects of natural and semi-synthetic cucurbitacins make them attractive as new drug candidates. Moreover, cucurbitacins have the capability to form conjugates with other anticancer drugs which will synergistically enhance their anticancer effects. The authors believe that in order to get lead compounds, there should be a greater focus on the synthesis of homodimers, heterodimers, and halo derivatives of cucurbitacins. In the opinion of the authors the analysis of the published patents on the cucurbitacins indicates that these compounds can be developed into a regimen to treat a wide spectrum of cancers.

scholarly journals Photonic Crystal Nanobeam Cavities for Nanoscale Optical Sensing: A Review

Micromachines ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 72 ◽  
Author(s):  
Da-Quan Yang ◽  
Bing Duan ◽  
Xiao Liu ◽  
Ai-Qiang Wang ◽  
Xiao-Gang Li ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Optical Waveguides ◽  
Optical Sensing ◽  
Early Stage ◽  
Disease Diagnosis ◽  
Label Free ◽  
Quality Factors ◽  
Integrated Sensor ◽  
Early Stage Disease ◽  
Wide Range

The ability to detect nanoscale objects is particular crucial for a wide range of applications, such as environmental protection, early-stage disease diagnosis and drug discovery. Photonic crystal nanobeam cavity (PCNC) sensors have attracted great attention due to high-quality factors and small-mode volumes (Q/V) and good on-chip integrability with optical waveguides/circuits. In this review, we focus on nanoscale optical sensing based on PCNC sensors, including ultrahigh figure of merit (FOM) sensing, single nanoparticle trapping, label-free molecule detection and an integrated sensor array for multiplexed sensing. We believe that the PCNC sensors featuring ultracompact footprint, high monolithic integration capability, fast response and ultrahigh sensitivity sensing ability, etc., will provide a promising platform for further developing lab-on-a-chip devices for biosensing and other functionalities.

scholarly journals Greater trochanteric pain syndrome: Evaluation and management of a wide spectrum of pathology

2021 ◽  
Vol 9 ◽  
pp. 205031212110225
Author(s):  
Mark A Pianka ◽  
Joseph Serino ◽  
Steven F DeFroda ◽  
Blake M Bodendorfer
Keyword(s):  
Wide Spectrum ◽  
Pain Syndrome ◽  
Operative Management ◽  
Hip Pain ◽  
Greater Trochanteric Pain Syndrome ◽  
Trochanteric Bursitis ◽  
Treatment Indications ◽  
Careful Clinical Examination ◽  
Wide Range ◽  
Tendon Pathology

Greater trochanteric pain syndrome is a common cause of lateral hip pain, encompassing a spectrum of disorders, including trochanteric bursitis, abductor tendon pathology, and external coxa saltans. Greater trochanteric pain syndrome is primarily a clinical diagnosis, and careful clinical examination is essential for accurate diagnosis and treatment. A thorough history and physical exam may be used to help differentiate greater trochanteric pain syndrome from other common causes of hip pain, including osteoarthritis, femoroacetabular impingement, and lumbar stenosis. Although not required for diagnosis, plain radiographs and magnetic resonance imaging may be useful to exclude alternative pathologies or guide treatment of greater trochanteric pain syndrome. The majority of patients with greater trochanteric pain syndrome respond well to conservative management, including physical therapy, non-steroidal anti-inflammatory drugs, and corticosteroid injections. Operative management is typically indicated in patients with chronic symptoms refractory to conservative therapy. A wide range of surgical options, both open and endoscopic, are available and should be guided by the specific etiology of pain. The purpose of this review is to highlight pertinent clinical and radiographic features used in the diagnosis and management of greater trochanteric pain syndrome. In addition, treatment indications, techniques, and outcomes are described.

scholarly journals Non-Albumin Proteinuria (NAP) as a Complementary Marker for Diabetic Kidney Disease (DKD)

Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 224
Author(s):  
Jaehyun Bae ◽  
Young Jun Won ◽  
Byung-Wan Lee
Keyword(s):  
Kidney Disease ◽  
Filtration Rate ◽  
Diabetic Kidney Disease ◽  
Estimated Glomerular Filtration Rate ◽  
Early Stage ◽  
Screening Tools ◽  
Tubular Injury ◽  
Current Standard ◽  
Diabetic Kidney ◽  
Wide Range

Diabetic kidney disease (DKD) is one of the most common forms of chronic kidney disease. Its pathogenic mechanism is complex, and it can affect entire structures of the kidney. However, conventional approaches to early stage DKD have focused on changes to the glomerulus. Current standard screening tools for DKD, albuminuria, and estimated glomerular filtration rate are insufficient to reflect early tubular injury. Therefore, many tubular biomarkers have been suggested. Non-albumin proteinuria (NAP) contains a wide range of tubular biomarkers and is convenient to measure. We reviewed the clinical meanings of NAP and its significance as a marker for early stage DKD.

scholarly journals Detectivity optimization to detect of ultraweak light fluxes with an EM-CCD as binary photon counter array

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ibtissame Khaoua ◽  
Guillaume Graciani ◽  
Andrey Kim ◽  
François Amblard
Keyword(s):  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Photon Counting ◽  
Detection Methods ◽  
Strong Nonlinearity ◽  
Wide Range ◽  
Depth Analysis ◽  
Spatially Extended ◽  
Extended Sources ◽  
Photon Counting Mode

AbstractFor a wide range of purposes, one faces the challenge to detect light from extremely faint and spatially extended sources. In such cases, detector noises dominate over the photon noise of the source, and quantum detectors in photon counting mode are generally the best option. Here, we combine a statistical model with an in-depth analysis of detector noises and calibration experiments, and we show that visible light can be detected with an electron-multiplying charge-coupled devices (EM-CCD) with a signal-to-noise ratio (SNR) of 3 for fluxes less than $$30\,{\text{photon}}\,{\text{s}}^{ - 1} \,{\text{cm}}^{ - 2}$$ 30 photon s - 1 cm - 2 . For green photons, this corresponds to 12 aW $${\text{cm}}^{ - 2}$$ cm - 2 ≈ $$9{ } \times 10^{ - 11}$$ 9 × 10 - 11 lux, i.e. 15 orders of magnitude less than typical daylight. The strong nonlinearity of the SNR with the sampling time leads to a dynamic range of detection of 4 orders of magnitude. To detect possibly varying light fluxes, we operate in conditions of maximal detectivity $${\mathcal{D}}$$ D rather than maximal SNR. Given the quantum efficiency $$QE\left( \lambda \right)$$ Q E λ of the detector, we find $${ \mathcal{D}} = 0.015\,{\text{photon}}^{ - 1} \,{\text{s}}^{1/2} \,{\text{cm}}$$ D = 0.015 photon - 1 s 1 / 2 cm , and a non-negligible sensitivity to blackbody radiation for T > 50 °C. This work should help design highly sensitive luminescence detection methods and develop experiments to explore dynamic phenomena involving ultra-weak luminescence in biology, chemistry, and material sciences.

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