Search

The advent of portable Fourier-Transform Infrared (FTIR) and Raman spectrometers has revolutionized analysis capabilities, presenting the possibility of on-site contaminant identification without the need for specialized laboratory settings. Compared to laboratory instrumentation, portable spectroscopy is more prone to noise, and appropriate spectral processing procedures need to be established. This paper introduces a comprehensive methodology that integrates acquisition techniques, spectral analysis, and mathematical tools necessary for utilizing handheld spectrometers to diagnose plant contamination. It focuses on determining the efficacy of handheld FTIR, Raman spectroscopy, and digital imaging for detecting contaminants in two food plants, Basil ( Ocimum basilicum ) and Mint ( Mentha ). The study examines the impact of three pollutants: iron (II) sulphate ( F e S O 4 ), zinc (II) sulphate ( Z n S O 4 ), and copper (II) sulphate ( C u S O 4 ), on these plants, but also the necessary amount of measurements to spot the pollutants' effects. Measurements were conducted at the start, after 24 hours, and after 48 hours of exposure, on both fresh and dried plant leaves, as well as in solution. Spectral effects of each of the pollutants were identified with the use of multivariate statistical process control techniques. With the help of the developed methodologies, researchers can identify in-situ contaminant effects, exposure times and run diagnostics directly on the leaf both in alive and dried plants., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Pansharpening constitutes a category of data fusion techniques designed to enhance the spatial resolution of multispectral (MS) images by integrating spatial details from a high-resolution panchromatic (PAN) image. This process combines the high-spectral data of MS images with the rich spatial information of the PAN image, resulting in a pansharpened output ideal for more effective image analysis, such as object detection and environmental monitoring. Traditionally developed for satellite data, our paper introduces a novel pansharpening approach customized for the fusion of Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectrometry (EDS) data. The proposed method, grounded in Partial Least Squares regression with Discriminant Analysis (PLS-DA), significantly boosts the spatial resolution of EDS data while preserving spectral details. A key feature of this approach involves partitioning the PAN image into intensity bins and dynamically adapting this division in cases of overlapping compounds with similar average atomic numbers. We evaluate the method's effectiveness using in-house EDS images obtained from both even and uneven sample surfaces. Comparative analysis against existing benchmarks and state-of-the-art pansharpening techniques demonstrates superior performance in both spectral and spatial quality indicators for our method., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Fusion and quality enhancement of the low-resolution Energy Dispersive X-ray Spectroscopy (EDS) maps to Scanning Electron Microscopy (SEM) panchromatic images has been proven effective by various pansharpening algorithms. The present paper aims to target the preprocessing of these maps to enhance the efficiency of the pansharpening process, with as little information loss on the chemical distribution, and as little propagated noise as possible. EDS maps present different noise intensities depending on the flatness of the surface of the analyzed object. The uneven surface maps have limited analytical value due to the noise and have not been resolution-enhanced with pansharpening due to the noise propagation limitation. In this paper, different preprocessing methods are evaluated for enabling uneven-surface particles to pansharpening: background removal, upsampling, and noise filtering. The sequence of applying preprocessing steps is analyzed. The optimal order of preprocessing steps is (i) background removal, (ii) noise filtering, and (iii) interpolation. A methodology for each of these steps is presented in the paper. The best performing pansharpening methodology is chosen to be Affinity for individual map analysis and Wavelet for multi-elemental fusion purposes. Following the methodology results in high-resolution EDS maps, even for uneven-surface particles which are, for the first time in literature, subjected to pansharpening., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Photogrammetric methods enable the construction of 3D SEM models from 2D images. Most software for this purpose is designed for photographic images. The software tries to minimize modelling error but some uncertainty usually remains in the model. In such approaches no ground truth measurement for microscopic objects exists for comparison with the finished model. In the proposed method, a textured model surface is compared to the SEM images to map the error locations on the model. The method is illustrated using two datasets., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Interferonε (IFNε) is a unique type I IFN that has distinct functions from IFNα/β. IFNε is constitutively expressed at mucosal tissues, including the female genital mucosa, and is reported to be modulated by estrogen and seminal plasma. However, its regulation by cytokines, including TNFα, IL-1β, IL-6, IL-8, IL-17, IL-22 and IFNα, which are commonly present in the female genital mucosa, is not well documented in freshly isolated primary cervical cells from tissues. We determined the effect of these cytokines on gene expression of type I IFNs in an immortalized endocervical epithelial cell line (A2EN) and in primary cervical epithelial cells. Several pro-inflammatory cytokines were found to induce IFNε, and TNFα induced the strongest response in both cell types. Pretreatment of cells with the IκB inhibitor, which blocks the NF-κB pathway, suppressed TNFα-mediated IFNε gene induction and promoter activation. Expression of IFNα, IFNβ, and IFNε was differentially regulated in response to various cytokines. Taken together, our results show that regulation of these IFNs depends on cell type, cytokine concentration, and incubation time, highlighting the complexity of the cytokine network in the cervical epithelium.

A new capillary electrophoresis method was developed for the quantification of diisobutyldithiophosphate (DTP), diisobutyldithiophosphinate (DTPI) and ethyl and isobutyl xanthates (EX, IBX) all of which are used as thiol collectors in froth flotation. This method uses pressure assisted field amplified sample injection (PA-FASI) to concentrate the analytes at the capillary inlet. The background electrolyte in electrophoretic separation was 60millimolar (mM) from 3-(cyclohexylamino)propane-1-sulfonic acid (CAPS) in 40mM NaOH solution. The similar CAPS electrolyte solution has earlier been used for screening for diuretics that contained sulphonamide and/or carboxylic groups. In this study, the functional groups are xanthate, phosphate and phosphinate. The method was developed using actual flotation process waters. The results showed that the water delivered from the plant did not contain significant amount of collectors; therefore, method development was accomplished by spiking analytes in these waters. Separation of analytes was achieved in 15min. The range of quantification was 0.27-66.6mg/L (R(2) 0.9991-0.9999) for all analytes other than ethyl xanthate, for which the range was 0.09-66.6mg/L (R(2) 0.9999). LOD (S/N=3) and LOQ (S/N=10) values for DTP, DTPI, IBX and EX were 0.05, 0.07, 0.06 and 0.01mg/L and 0.16, 0.25, 0.21 and 0.04mg/L, respectively. No interference from the matrices was observed, when the method was tested at a gold concentrator plant., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: We have previously shown that human defensin 5 (HD5) promotes HIV infectivity in both primary CD4+ T cells and HeLa cells expressing CD4 and CCR5. HD5 is induced in response to sexually transmitted infections (STIs) such as Chlamydia trachomatis and Neisseria gonorrhoeae, suggesting it plays a role in STI-mediated enhancement of HIV transmission. In contrast to our findings, a recent study reports that HD5 has an anti-HIV effect in primary CD4+ T cells under serum-deprived conditions. To resolve these apparently contradictory observations, we investigated experimental parameters that might contribute to contrasting effects of HD5., Results: Serum-deprived culture conditions were associated with anti-HIV activity. In contrast to the dependence of the HIV enhancing effect on HD5 structure, the anti-HIV activity in serum-deprived primary CD4+ T cells was independent of HD5 structure as the linear peptide [Abu] HD5 exhibited similar anti-HIV activity. Under serum deprived conditions, HD5 blocked CD4-receptor-independent HIV-1vsv infection before or after viral entry. We found that HD5 and its linear form induced significant cell death in primary CD4+ T cells under serum-deprived culture conditions. HD5-mediated apoptosis was observed as early as 2 h after addition of defensins to serum-deprived primary CD4+ T cells. In contrast to primary CD4+ T cells, HD5 did not induce cytotoxicity and promote HIV infectivity of HeLa-CD4-CCR5 cells under serum-deprived conditions., Conclusions: These results indicate that under serum-deprived culture conditions HD5 is toxic for primary CD4+ T cells, warranting caution in data interpretation.

Vector quantization (VQ) is a well-known lossy compression method, which has not often been applied to biosignals. In this paper, VQ and its mean residual variant for encoding and decoding electromyography (EMG) signals have been tested. The methods are selected in such a way that they can be later applied in a low-resource embedded system. A neural network approach is used for codebook generation. The preservation of medical parameters is a prominent sign of quality in medical compression systems. Both signal level fidelity factors and preserving medical parameters are tested. The results show that mean residual vector quantization with short segments is a workable approach for EMG signal compression.

We studied the modification of auditory perception in three different conditions in twenty subjects. Observing other person's discordant articulatory gestures deteriorated identification of acoustic speech stimuli and modified the auditory percept, causing a strong McGurk effect. A similar effect was found when the subjects watched their own silent articulation in a mirror and acoustic stimuli were simultaneously presented to their ears. Interestingly, a smaller but significant effect was even obtained when the subjects just silently articulated the syllables without visual feedback. On the other hand, observing other person's or one's own concordant articulation and silently articulating a concordant syllable improved identification of the acoustic stimuli. The modification of auditory percepts caused by visual observation of speech and silently articulating it are both suggested to be due to the alteration of activity in the auditory cortex. Our findings support the idea of a close relationship between speech perception and production.

The aim of this study was to evaluate and clarify the usefulness of different spectral characteristics of myoelectrical activity in the follow-up of development of muscle fatigue. Vastus lateralis (part of quadriceps) muscle loaded in a simple isokinetic exertion test was used as a model. Twelve, well trained athletes served as study subjective to minimize the inter-individual variations. They went through one-minute test with isokinetic device at the range of 90 degrees extension and flexion at the level of their maximal force. The myoelectrical signals were registered from middle of the vastus lateralis muscle by a computerized fast Fourier transform analyzing system based on 80286 and 80287 microprocessors and using surface electrodes. Mean power frequency (MPF) was 65.6 (SE=Standard Error, 1.6) Hz, median frequency (MF) 55.8 Hz and zero crossing rate (ZCR) 92.5 (SE 1.5) during first performance. All these parameters decreased apparently linearly and significantly from the beginning of the test (P<0.001). The decrease rate of ZCR was fastest and MF slowest. The area of power spectrum (PSA) was 1753 (SE 320) units during first performance, and it increased markedly with slightly accelerating rate during the test. In conclusion, for the evaluation of the muscular performance during the development of fatigue it is beneficial to monitor simultaneously MPF, MF and ZCR.

Objective: To assess low back pain (LBP) intensity and subjective disability during pregnancy and compare the pain scores with lumbar motion patterns., Design: A prospective study of pregnant back pain sufferers and healthy controls., Setting: Kuopio University Hospital, Kuopio, Finland., Participants: Study group consisted of 32 pregnant women with LBP; control group consisted of 21 healthy pregnant women., Main Outcome Measures: Back pain intensity was assessed by visual analog scale (VAS), and subjective disability index was measured by Oswestry Low Back Disability Questionnaire, at 20 and 36 weeks of pregnancy. Back muscle activities were recorded by surface electromyography, and movement sensors were used to detect lumbar motion., Results: In the study group current pain scores (VAS) at first and last trimester correlated strongly (r = .82, p < .00). Pain scores correlated with body weight at the first trimester (r = .54, p = .003) and at the last trimester (r = .67, p < .00). Significant correlation was noted between current pain intensity and back muscle activity level during forward body flexion at first trimester (r = .704, p < .00). Back muscle activity during bending measured at first trimester significantly correlated with pain intensity at last trimester (r = .703, p < .00). Back muscle activity during the first trimester of pregnancy had a negative correlation with current (r = -.57, p = .002) and later subjective disability index (r = -.42, p = .02). It correlated inversely (r = -.54, p = .003) with pain score at last trimester of pregnancy, ie, the lower the back muscle activity at the beginning of pregnancy, the more pain and disability throughout pregnancy. In the control group, three women developed LBP and disability feelings during pregnancy. They had increased muscle activity during flexion at delivery, ie, disturbed flexion relaxation., Conclusions: Prepregnancy LBP predicts renewed pain during pregnancy, and dysfunction of back muscles has been established in LBP. In this study, disturbance in the relaxation of the back muscles was linearly related to current, and also to later, pain scores. In addition, back muscle activity level was inversely related to the disability index. For the first time, it has been shown prospectively that the function pattern of back extensors seems to predict, and is related to, future back pain. Simple function testing is promising and might be valuable in identifying mothers with a high risk of pregnancy-related back pain and in directing preventive intervention to high risk women by making them aware of self-treatment methods.

Objective: This study investigated the simultaneous activity of back muscles and hamstring muscles during sagittal forward body flexion and extension in healthy persons. The study was cross-sectional., Design: A descriptive study of paraspinal and hamstring muscle activity in normal persons during lumbar-pelvic rhythm., Setting: A university hospital., Participants: Forty healthy volunteers (21 men, 19 women, ages 17 to 48 years), all without back pain or other pain syndromes., Main Outcome Measures: Surface electromyography (EMG) was used to follow activities in the back and the hamstring muscles. With movement sensors, real lumbar flexion was separated from simultaneous pelvic motion by monitoring the components of motion with a two-inclinometer method continuously from the initial upright posture into full flexion. All signals were sampled during real-time monitoring for off-line analyses., Results: Back muscle activity ceased (ie, flexion relaxation [FR] occurred) at lumbar flexion with a mean of 79 degrees. Hamstring activity lasted longer and EMG activity ceased in the hamstrings when nearly full lumbar flexion (97%) was reached. After this point total flexion and pelvic flexion continued further, so that the last part of lumbar flexion and the last part of pelvic flexion happened without back muscle activity or hamstring bracing, respectively., Conclusions: FR of the back muscles during body flexion has been well established and its clinical significance in low back pain has been confirmed. In this study, it was shown for the first time that the hip extensors (ie, hamstring muscles) relax during forward flexion but with different timing. FR in hamstrings is not dependent on or coupled firmly with back muscle behavior in spinal disorders and the lumbar pelvic rhythm can be locally and only partially disturbed.

Study Design: A cross-sectional analysis was done of patients with recurrent low back pain referring to the lower limbs., Objectives: To analyze dynamic radiographs of forward and backward bending of the lumbar back and to determine, using routine neurophysiologic measurements, the functional state of the lower nerve roots in patients with recurrent low back pain radiating to the lower limbs., Methods: Clinical and neurophysiologic studies showed eight of the 108 patients with low back pain to have ventral root impingement at either L5 or S1 level. The remaining 100 patients, 56 women and 44 men (mean age, 37.6 years; range, 17-62 years), made up the study group for continuing investigation. History of low back pain ranged from 4 months to 20 years., Results: Disturbed intervertebral movement was found in 51 of 100 patients. Twenty-seven percent had L5 or L4 anterolisthetic hypermobility, and 35% had L4 or L3 vertebral retrolisthesis. Vaguely delineated radiating sensations in the lower limbs were common (62%). Back muscle electromyographs were mostly (86%) normal in patients whose low back pain was localized. Conversely, almost three-fourths of those experiencing radiating or referred pain had abnormal electromyographs, consistent with a mild degree of axonal damage in the posterior branch of the lumbar nerve root innervating the medial paraspinal muscles. This finding was most common among patients with retrolisthesis and simultaneous degenerative changes., Conclusions: Evaluation of low back pain should include tests for degenerative retrolisthesis, especially in patients experiencing radiating sensations with no evidence of root impingement, because abnormal electromyographic findings showing denervation of the paraspinal muscles was most common in patients with degenerative retrolisthesis. To improve the functional support of the lumbar region, rehabilitation should be directed to the medial back muscles because they provide the most effective support for intervertebral motion and because mild disturbances appear to be associated with their innervation in recurrent low back pain.

Results of decompressive surgery for lumbar spinal stenosis vary. We evaluated the density of lumbar muscles by computed tomography (CT) at the L2-L4 levels in patients 4 years after they had undergone surgery for lumbar spinal stenosis. Twenty of these patients had an excellent outcome clinically, and 16 patients had very poor outcome. The residual stenosis and density of lumbar muscles in Hounsfield units were measured on CT images. The clinical evaluation of outcome also included the Oswestry questionnaire and a walking test. The density of lumbar flexors was higher in the group with excellent results than in the group with poor results. The density of lumbar extensors showed a marked decrease in the operated area. These results suggest that the decrease of muscular density can be partially explained by disuse or inactivity. The decrease in the operated area probably reflects muscular atrophy caused by muscle denervation.