Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
375 result(s) for "double threshold method"
Sort by:
Improving the sorting efficiency of maize haploid kernels using an NMR-based method with oil content double thresholds
Background Maize haploid breeding technology can be used to rapidly develop homozygous lines, significantly shorten the breeding cycle and improve breeding efficiency. Rapid and accurate sorting haploid kernels is a prerequisite for the large-scale application of this technology. At present, the automatic haploid sorting based on nuclear magnetic resonance (NMR) using a single threshold method has been realized. However, embryo-aborted (EmA) kernels are usually produced during in vivo haploid induction, and both haploids and EmA kernels have lower oil content and are separated together using a single threshold method based on NMR. This leads to a higher haploid false discrimination rate (FDR) and requires secondary manual sorting to select the haploid kernels from the mixtures, which increases the sorting cost and decreases the haploid sorting efficiency. In order to improve the correct discrimination rate (CDR) in sorting haploids, a method to distinguish EmA kernels is required. Results Single kernel weight and oil content were measured for the diploid, haploid, and EmA kernels derived from three maize hybrids and nine inbred lines by in vivo induction. The results showed that the distribution of oil content showed defined boundaries between the three types of kernels, while the single kernel weight didn't. According to the distribution of oil content in the three types of kernels, a double-threshold method was proposed to distinguish the embryo-aborted kernels, haploid and diploid kernels based on NMR and their oil content. The double thresholds were set based on the minimum oil content of diploid kernels and the maximum content of EmA kernels as the upper and lower boundary values, respectively. The CDR of EmA kernels in different maize materials was > 97.8%, and the average FDR was reduced by 27.9 percent. Conclusions The oil content is an appropriate indicator to discriminate diploid, haploid and EmA kernels. An oil content double-threshold method based on NMR was first developed in this study to identify the three types of kernels. This methodology could reduce the FDR of haploids and improve the sorting efficiency of automated sorting system. Thus, this technique represents a potentially efficient method for haploid sorting and provides a reference for the process of automated sorting of haploid kernels with high efficiency using NMR.
Research on Digital Image Record in Intangible Cultural Heritage Inheritance Innovation under the Background of Big Data
The purpose of this paper is to investigate the digital lens presentation effect and image dissemination effect of intangible cultural heritage. In order to test the lens boundary detection technology of ICH digital images, we focus on analyzing the number of image frames, the number of mutations and the number of gradual changes of ICH characters, space-time and events, and exploring the checking completeness, the checking accuracy and the comprehensive detection rate of this paper’s algorithm and the dual-threshold comparative method on different types of ICH image fragments. Combined with the descriptive analysis of valid samples, we explore the main types of transmission of NRM digital images and clarify the degree of media utilization and the ranking of transmission power of NRM digital images in the Yangtze River Delta region. Shanghai has the strongest online dissemination power of traditional theater, traditional fine arts and traditional arts and crafts, with 1284586, 310468, and 237818, respectively, while traditional music, Chinese opera and folklore have the weakest dissemination power in Shanghai. Traditional music makes up 18.73% of them. To ensure non-heritage culture’s inheritance, it is necessary to strengthen the use of digital imaging technology to achieve linkage communication between non-heritage cultures and build an overall communication system.
Event Detection and Classification for Fiber Optic Perimeter Intrusion Detection System
A perimeter intrusion detection system (PIDS) is critical for the security of a shale gas field. Among many technologies, the fiber optic sensor-based method is the most widely used, due to its passive, low-cost, long-life, and strong anti-interference ability and strong environmental adaptability. This article proposes an event detection and classification method for a fiber optic PIDS. In general, three types of features are extracted for an improved double-threshold method to improve the probability of detection. Also, the detected intrusion events are distinguished by a support vector machine with wavelet features to reduce the nuisance alarm rate. Experiments on the PIDS in Chongqing Fuling's shale gas field show that detection algorithms based on the feature of short-time energy and short-time wavelet coefficient energy are much better, and the performance of event classification is satisfactory.
Research on an Adaptive Variational Mode Decomposition with Double Thresholds for Feature Extraction
A motor bearing system is a nonlinear dynamics system with nonlinear support stiffness. It is an asymmetry system, which plays an extremely important role in rotating machinery. In this paper, a center frequency method of double thresholds is proposed to improve the variational mode decomposition (VMD) method, then an adaptive VMD (called DTCFVMD) method is obtained to extract the fault feature. In the DTCFVMD method, a center frequency method of double thresholds is a symmetry method, which is used to determine the decomposed mode number of VMD according to the power spectrum of the signal. The proposed DTCFVMD method is used to decompose the nonlinear and non-stationary vibration signals of motor bearing in order to obtain a series of intrinsic mode functions (IMFs) under different scales. Then, the Hilbert transform is used to analyze the envelope of each mode component and calculate the power spectrum of each mode component. Finally, the power spectrum is used to extract the fault feature frequency for determining the fault type of the motor bearing. To test and verify the effectiveness of the DTCFVMD method, the actual fault vibration signal of the motor bearing is selected in here. The experimental results show that the center frequency method of double thresholds can effectively determine the mode number of the VMD method, and the proposed DTCFVMD method can accurately extract the clear time frequency characteristics of each mode component, and obtain the fault characteristics of characteristics; frequency, rotating frequency, and frequency doubling and so on.
Minocycline does not affect experimental pain or addiction-related outcomes in opioid maintained patients
RationaleMinocycline, a tetracycline antibiotic, inhibits activation of microglia. In preclinical studies, minocycline prevented development of opioid tolerance and opioid-induced hyperalgesia (OIH). The goal of this study was to determine if minocycline changes pain threshold and tolerance in individuals with opioid use disorder who are maintained on agonist treatment.MethodsIn this double-blind, randomized human laboratory study, 20 participants were randomized to either minocycline (200 mg/day) or placebo treatment for 15 days. The study had three test sessions (days 1, 8, and 15 of treatment) and one follow-up visit 1 week after the end of treatment. In each test session, participants were assessed on several subjective and cognitive measures, followed by assessment of pain sensitivity using the Cold Pressor Test (CPT). Daily surveys and cognitive measures using Ecological Momentary Assessment (EMA) were also collected four times a day on days 8 through 14 of treatment, and proinflammatory serum cytokines were assessed before and on the last day of treatment.ResultsMinocycline treatment did not change pain threshold or tolerance on the CPT. Similarly, minocycline did not change severity of pain, opioid craving, withdrawal, or serum cytokines. Minocycline treatment increased accuracy on a Go/No-Go task.ConclusionsWhile these findings do not support minocycline’s effects on OIH, minocycline may have a potential use as a cognitive enhancer for individuals with opioid use disorder, a finding that warrants further systematic studies.
Kratom and Pain Tolerance: A Randomized, Placebo-Controlled, Double-Blind Study
: Kratom has a long history of traditional medicine use in Southeast Asia. Consumption of kratom products has also been reported in the US and other regions of the world. Pain relief is among many self-reported kratom effects but have not been evaluated in controlled human subject research. : Kratom effects on pain tolerance were assessed in a randomized, placebo-controlled, double-blind study. During a 1-day inpatient stay, participants received a randomized sequence of kratom and placebo decoctions matched for taste and appearance. Pain tolerance was measured objectively in a cold pressor task (CPT) as time (seconds) between the pain onset and the hand withdrawal from the ice bath. Health status, vital signs, objective, and subjective indicators of withdrawal symptoms, self-reported data on lifetime kratom use patterns, and assessments of blinding procedures were also evaluated. : Twenty-six males with the mean (SD) age 24.3 (3.4) years were enrolled. They reported the mean (SD) 6.1 (3.2) years of daily kratom consumption. Pain tolerance increased significantly 1 hour after kratom ingestion from the mean (SD) 11.2 (6.7) seconds immediately before to 24.9 (39.4) seconds 1 hour after kratom consumption (F(2,53.7)=4.33, p=0.02). Pain tolerance was unchanged after consuming placebo drinks: 15.0 (19.0) seconds immediately before and 12.0 (8.1) seconds 1 hour after consumption of placebo (F(2,52.8)=0.93, p=0.40). No discomfort or signs of withdrawal were reported or observed during 10-20 hours of kratom discontinuation. : Kratom decoction demonstrated a substantial and statistically significant increase in pain tolerance. Further rigorous research on kratom pain-relieving properties and a safety profile is needed.
Differences in sensory nerve block between levobupivacaine and bupivacaine at low concentrations in humans and animals
Physiochemical properties of levobupivacaine and bupivacaine are identical, but pharmacokinetic and pharmacodynamics properties differ due to stereoselective interactions at the molecular sites of action. An evaluation of nerve block characteristics is essential for optimal clinical application. This study compared the sensory blocking characteristics of levobupivacaine to bupivacaine in humans and model animals. Levobupivacaine and bupivacaine were compared for sensory block efficacy using a randomized, double-blinded, crossover study design. Eighteen healthy volunteers were randomized to receive levobupivacaine or bupivacaine by subcutaneous injection into the forearm, followed by the other drug 1 week later with injection order counterbalanced across subjects. Tactile detection and mechanical pain thresholds were determined using von Frey hairs and thermal pain threshold using a thermal stimulator. Effects of levobupivacaine and bupivacaine, on the spiking activity of spinal dorsal horn (SDH) neurons evoked by innocuous or noxious stimuli were also compared in anesthetized Sprague–Dawley rats by in vivo extracellular recordings. There were no significant differences in mechanical and thermal pain thresholds following levobupivacaine or bupivacaine injection at 0.025%, 0.0625%, and 0.125%. There was also no significant difference in tactile detection threshold following levobupivacaine or bupivacaine injection at 0.125%. However, tactile detection threshold was significantly higher after administration of bupivacaine at 0.025% and 0.0625% compared to equivalent doses of levobupivacaine. Subcutaneous injection of bupivacaine at 0.05% also induced significantly greater inhibition of SDH neuron spiking activity evoked by innocuous stimuli compared to an equivalent dose of levobupivacaine, while there was no significant difference in suppression of spiking activity evoked by noxious stimuli. Low-dose bupivacaine induces greater suppression tactile sensation than low-dose levobupivacaine. Thus, low-dose levobupivacaine demonstrates relatively greater blocking selectivity for noxious over innocuous stimuli compared to low-dose bupivacaine. Levobupivacaine may be advantageous for applications where pain must be suppressed but non-nociceptive sensations maintained.
Acute analgesic effect of nicotine vaping using three experimental pain induction tasks: a randomized, placebo-controlled laboratory study
Rationale Pain and nicotine use are co-occurring conditions with a significant impact on health. Experimental evidence supports an acute analgesic effect of nicotine which may reinforce nicotine use among those with chronic pain. Evidence for nicotine analgesia have primarily been gathered in combustible cigarette users and have not been extended to electronic nicotine delivery systems (ENDS or vaping). Furthermore, the mechanisms of nicotine analgesia in humans are not well understood. Objectives Assess the effect of acute vaped nicotine on subjective and behavioral indices of pain sensitivity using three tasks designed to probe distinct mechanisms of analgesia. Methods This study recruited ENDS users ( N  = 86) to undergo a paced vaping protocol followed by pain tasks in counterbalanced order. Across four sessions, participants vaped e-liquid containing nicotine or placebo, and flavor or no-flavor in a 2 × 2 within-subject design. Assessments included cold pressor, submaximal effort tourniquet to induce ischemic pain, and temporal summation of heat pain, an index of central sensitization. Results Compared to placebo, nicotine increased cold pressor pain tolerance (η p 2  = 0.031), ischemic pain threshold (η p 2  = 0.073) and tolerance (η p 2  = 0.056) but had no effect on temporal summation of pain. Flavor did not affect pain sensitivity. Females reported greater ischemic pain sensitivity (η p 2  = 0.027) and greater reductions in craving (η p 2  = 0.086). Conclusions Consistent with research from tobacco smoking, analgesia may be reinforcing and contribute to nicotine dependence among ENDS users. More research on sex differences is warranted.
Pegcetacoplan for the treatment of geographic atrophy secondary to age-related macular degeneration (OAKS and DERBY): two multicentre, randomised, double-masked, sham-controlled, phase 3 trials
Geographic atrophy is a leading cause of progressive, irreversible vision loss. The objectives of OAKS and DERBY were to assess the efficacy and safety of pegcetacoplan compared with sham treatment in patients with geographic atrophy. OAKS and DERBY were two 24-month, multicentre, randomised, double-masked, sham-controlled, phase 3 studies, in which patients aged 60 years and older with geographic atrophy secondary to age-related macular degeneration were enrolled at 110 clinical sites and 122 clinical sites worldwide, respectively. Patients were randomly assigned (2:2:1:1) by central web-based randomisation system to intravitreal 15 mg per 0·1 mL pegcetacoplan monthly or every other month, or sham monthly or every other month using stratified permuted block randomisation (stratified by geographic atrophy lesion area at screening, history or presence of active choroidal neovascularisation in the eye not under assessment, and block size of six). Study site staff, patients, reading centre personnel, evaluating physicians, and the funder were masked to group assignment. Sham groups were pooled for the analyses. The primary endpoint was the change from baseline to month 12 in the total area of geographic atrophy lesions in the study eye based on fundus autofluorescence imaging, in the modified intention-to-treat population (ie, all patients who received one or more injections of pegcetacoplan or sham and had a baseline and at least one post-baseline value of lesion area). Key secondary endpoints (measured at 24 months) were change in monocular maximum reading speed of the study eye, change from baseline in mean functional reading independence index score, change from baseline in normal luminance best-corrected visual acuity score, and change from baseline in the mean threshold sensitivity of all points in the study eye by mesopic microperimetry (OAKS only). Safety analyses included patients who were randomly assigned and received at least one injection of pegcetacoplan or sham. The now completed studies are registered with ClinicalTrials.gov, NCT03525613 (OAKS) and NCT03525600 (DERBY). Between Aug 30, 2018, and July 3, 2020, 1258 patients were enrolled in OAKS and DERBY. The modified intention-to-treat populations comprised 614 (96%) of 637 patients in OAKS (202 receiving pegcetacoplan monthly, 205 pegcetacoplan every other month, and 207 sham) and 597 (96%) of 621 patients in DERBY (201 receiving pegcetacoplan monthly, 201 pegcetacoplan every other month, and 195 sham). In OAKS, pegcetacoplan monthly and pegcetacoplan every other month significantly slowed geographic atrophy lesion growth by 21% (absolute difference in least-squares mean –0·41 mm2, 95% CI –0·64 to –0·18; p=0·0004) and 16% (–0·32 mm2, –0·54 to –0·09; p=0·0055), respectively, compared with sham at 12 months. In DERBY, pegcetacoplan monthly and pegcetacoplan every other month slowed geographic atrophy lesion growth, although it did not reach significance, by 12% (–0·23 mm2, –0·47 to 0·01; p=0·062) and 11% (–0·21 mm2, –0·44 to 0·03; p=0·085), respectively, compared with sham at 12 months. At 24 months, pegcetacoplan monthly and pegcetacoplan every other month slowed geographic atrophy lesion growth by 22% (–0·90 mm2, –1·30 to –0·50; p<0·0001) and 18% (–0·74 mm2, –1·13 to –0·36; p=0·0002) in OAKS, and by 19% (–0·75 mm2, –1·15 to –0·34; p=0·0004) and 16% (–0·63 mm2, –1·05 to –0·22; p=0·0030) in DERBY, respectively, compared with sham. There were no differences in key secondary visual function endpoints at 24 months. Serious ocular treatment-emergent adverse events were reported in five (2%) of 213, four (2%) of 212, and one (<1%) of 211 patients in OAKS, and in four (2%) of 206, two (1%) of 208, and two (1%) of 206 patients in DERBY receiving pegcetacoplan monthly, pegcetacoplan every other month, and sham, respectively, at 24 months. New-onset exudative age-related macular degeneration was reported in 24 (11%), 16 (8%), and four (2%) patients in OAKS, and in 27 (13%), 12 (6%), and nine (4%) patients in DERBY receiving pegcetacoplan monthly, pegcetacoplan every other month, and sham, respectively, at 24 months. Pegcetacoplan, the first treatment approved by the US Food and Drug Administration for geographic atrophy, slowed geographic atrophy lesion growth with an acceptable safety profile. Apellis Pharmaceuticals.