Near-infrared Spectroscopy Research Articles

Rapid identification of fragrant rice using starch flavor compound via NIR spectroscopy coupled with GC–MS and Badh2 genotyping

The identification of fragrant rice varieties using near-infrared reflectance spectroscopy (NIRS) models has attracted extensive attention from regulatory authorities worldwide. In this study, 138 fragrant and 54 nonfragrant rice varieties were planted in the same region and distinguished using sensory evaluation, gas chromatography–mass spectrometry analysis, and betaine aldehyde dehydrogenase 2 (Badh2) genotyping. Then, the 2-acetyl−1-pyrroline (2-AP) content was assessed based on partial least-squares discriminant (PLS-DA) models generated after 2nd individually or combined with SNV/MSC/smoothing preprocessing successfully classified fragrant rice both in the calibration and predictive sets. Moreover, design of experiments (DoE)-based preprocessing selection was employed as an effective strategy to optimize the calibration models compared with the one variable at a time (OVAT) method. Further, Badh2 genotype sample screening assisted with identifying authentic fragrant rice and guaranteed the NIRS model's prediction accuracy in identifying fragrant rice. In conclusion, the high throughput PLS-DA multivariate method coupled with NIRS data was applied to identify fragrant rice varieties in routine monitoring and was effective, accurate, and rapid.

Near-infrared spectroscopy during mouth opening in alpacas at two different head heights

Near-infrared spectroscopy during mouth opening in alpacas at two different head heights

Cr3+-doped Na2CaSn2Ge3O12 garnet showing broadband near-infrared emission at 820 nm with zero thermal quenching and near-unity quantum yield

The continually advancing near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) hold pivotal significance in optical imaging and NIR spectroscopy. Cr3+-doped garnet broadband NIR phosphors have attracted considerable attention owing to their high optical performance enabled by the rigid structure. Nonetheless, the emission wavelength is severely restricted, and longer wavelength emissions usually result in inferior quantum efficiency and poor luminescence stability. In this work, the concurrent reconstruction of dodecahedral and octahedral sites by introducing [Na+-Sn4+]C unit in the framework of Na2CaSn2Ge3O12 garnet contributes to the Cr3+ broadband NIR emission spanning 700–1200 nm, with a peak at 820 nm. Utilizing a charge compensation strategy via Ta5+ codoping largely boosts the internal quantum efficiency (IQE) of Na2CaSn2Ge3O12:Cr3+ from 93.06 % up to 95.04 %. Trap-mediated energy compensation is proposed to achieve a record-breaking zero-thermal-quenching behavior (99.39 %@423 K) of Cr3+-doped garnet with such a longer wavelength emission. The encapsulated prototype broadband NIR pc–LED gives rise to an overwhelming NIR output power of 590.9 mW@1300 mA and a photoconversion efficiency (PCE) of 32.62 % at 30 mA, rendering exceptional performance in night vision, detection, and NIR imaging applications.

A novel Cr3+-doped MgGaBO4 phosphor: expanding the horizons in plant illumination

Near-infrared (NIR) spectroscopy technology has demonstrated unparalleled efficacy in night vision, iris authentication, plant illumination, food inspection, and various other domains. Nonetheless, the quest for novel phosphors exhibiting superior luminescent efficiency and enduring thermal stability persists as a formidable obstacle. In this study, phosphors MgGaBO4: Cr3+, Al3+ were successfully synthesized by high-temperature solid-phase reaction method. Firstly, starting from MgGaBO4: Cr3+, the crystal field environment around Cr3+ ions was modulated by replacing Ga3+ with Al3+ to further improve the luminescence performance of the phosphor. The emission peak wavelength of MgGaBO4: 0.0075Cr3+,0.005Al3+ phosphor was about 756 nm, the full width at half-maximum (FWHM) was about 174 nm under the blue light excitation of 440 nm. In addition, the luminescence intensity at 100 °C remains at 77.41% of that at room temperature. Finally, the excellent moisture resistance of this phosphor was demonstrated. This work not only introduces a novel broadband NIR phosphor with promising application potential in advanced agricultural lighting but also proposes a synergistic enhancement strategy for effectively improving the performance of broadband NIR phosphor-converted LED light sources.

Limits for the Identification of Smectites Mixed with Common Minerals Based on Short-Wave Infrared Spectroscopy

The identification of minerals, particularly clay minerals, using visible, near-infrared, and short-wave infrared (VNIR-SWIR) spectroscopy has gained prominence due to its efficiency and the advancement of remote hyperspectral sensors. However, identifying minerals in polymineralic samples remains challenging due to overlapping absorption features. This study prepared systematic binary mixtures of two smectites (dioctahedral and trioctahedral) with common non-clay minerals (calcite, dolomite, gypsum, quartz, and feldspar). Spectra from these mixtures were obtained using the ASD FieldSpec 4 Hi-Res spectroradiometer and analyzed with continuum removal and second derivative preprocessing to define detection limits. These limits indicate the minimum percentage of each mineral required for clear identification in various smectite–non-clay combinations. After continuum removal, smectites are identified at ≥5%–10% in mixtures with carbonates, quartz, and feldspar, but ≥70% is needed for gypsum. Non-clay minerals have detection limits of ≥70% for calcite and 20% for gypsum in the presence of smectites, while dolomite remains undetectable. The second derivative improves these limits, enabling smectite identification at 5% in carbonate mixtures and 5%–15% in gypsum mixtures. Calcite detection limits are 65%, and dolomite can be identified at ≥65% and ≥85% with dioctahedral and trioctahedral smectites, respectively. Gypsum detection limits are reduced to 10%, while quartz and feldspar cannot be identified due to lacking absorption features.

Non-Invasive NIR Spectroscopy for Precise Water Content Determination in Sumatran Coffee Beans

Non-Invasive NIR Spectroscopy for Precise Water Content Determination in Sumatran Coffee Beans

Detection of Illicit Conservation Treatments in Sea Bass (Dicentrarchus labrax): Application and Data Integration of NIR Spectrometers

Global fish and seafood consumption is increasing annually, frequently leading to the emergence of food fraud, mainly related to mislabeling and adulteration like, for example, the use of illicit/unauthorized food additives to mask or delay fish spoilage. Among the available diagnostic tools for control purposes, spectroscopic techniques have often been proposed to identify these kinds of illicit practices in fish and seafood products. The presented study aims to test two cheap and portable near infrared (NIR) spectrometers, a handheld MicroNIR and a pocket-sized SCiO, to uncover use of the illicit food additive Cafodos, a mixture of sodium citrate and hydrogen peroxide used to preserve some fish characteristics (like smell, color, na dtexture). The NIR spectroscopy in combination with chemometric approaches, allowed the successfully classification of (81–100%) samples of sea bass (Dicentrarchus labrax) treated with Cafodos. The study highlights the potential of this technique that, by not requiring pre-treatment of samples with further reagents, is cheaper and safer for the environment. In conclusion, the study confirmed the potential of portable devices for rapid NIR spectroscopy analysis to identify food fraud and ensure consumer safety.

Identification of drug use degree by integrating multi-modal features with dual-input deep learning method.

Most of studies on drug use degree are based on subjective judgments without objective quantitative assessment, in this paper, a dual-input bimodal fusion algorithm is proposed to study drug use degree by using electroencephalogram (EEG) and near-infrared spectroscopy (NIRS). Firstly, this paper uses the optimized dual-input multi-modal TiCBnet for extracting the deep encoding features of the bimodal signal, then fuses and screens the features using different methods, and finally fused deep encoding features are classified. The classification accuracy of bimodal is found to be higher than that of single modal, and the classification accuracy is up to 89.9%.

Inclisiran-containing low-density lipoprotein cholesterol reduction effectively stabilizes atherosclerotic plaques

Abstract Background/Introduction Near-infrared spectroscopy (NIRS) allows to quantify lipid composition of coronary artery lesions. High plaque lipid content has been associated with increased adverse cardiovascular event risk. Purpose Aim of this study was to evaluate atherosclerotic plaque lipid content reduction in association with low-density lipoprotein (LDL-C) lowering on the background of intensive hypolipidaemic therapy. Methods NIRS investigation was performed in stable coronary artery disease patients having 20-50% stenosis in the proximal or middle third of a coronary artery. Segment of interest was repeatedly evaluated after 15 months. Lipid-rich plaques (LRPs) were defined as lesions with maximum lipid-core burden index within 4 mm (maxLCBI4 mm) >250. Study participants were taking high-intensity statin (atorvastatin 40 or 80 mg and rosuvastatin 20 or 40 mg) with or without ezetimibe for a run-in period of 4-6 weeks. Afterwards, in patients not achieving LDL-C level <1.8 mmol/l, add-on inclisiran was started. Baseline LDL-C was defined as the level at the time of initiation of optimal lipid-lowering therapy. Statistical significance level of 0.05 was set. Results Data of 36 patients was analyzed. Mean baseline maxLCBI4 mm was 203.9, reduced by 39.8% (-81.1, 95%CI -129.2 to -33.0) at 15-month follow-up (P=0.003). In 15 patients LRPs were detected with mean baseline maxLCBI4 mm 363.5, which was decreased by 35.8% (-130.3, 95%CI -235.0 to -25.7) (P=0.020). Mean LDL-C level at baseline was 2.5 mmol/l among all participants, lowered by 32.0% (-0.8, 95%CI -1.1 to -0.5) after 15 months of treatment (P<0.001). 19 patients received inclisiran in addition to high-dose statin and optional ezetimibe therapy. In 24 patients achieving LDL-C target <1.8 mmol/l at 15-month follow-up, a significant maxLCBI4 mm reduction from 208.5 by 48.4% (-101.0, 95%CI -169.3 to -32.7) was established (P=0.010). Among those having LDL-C >1.8 mmol/l, maxLCBI4 mm reduction from 194.7 by 21.2% (-41.25, 95%CI -94.7 to 12.2) was observed, however the change was not statistically significant (P=0.114). Conclusion LDL-C lowering with high-intensity hypolipidaemic therapy, including escalation to proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition, demonstrated atherosclerotic plaque stabilization by NIRS-detected lipid content decrease.

Coronary artery plaque characteristics in smokers assessed by intracoronary multi-modality imaging: a NIRS-IVUS guided PROSPECT II substudy

Abstract Background Smoking is a risk factor for coronary artery disease and myocardial infarction. Purpose Among patients with myocardial infarction, we hypothesized smokers would have increased prevalence of nonculprit high-risk plaque characteristics as assessed by intracoronary multimodality imaged when compared to nonsmokers. Method This is a prespecified post-hoc analysis of the PROSPECT II (Providing Regional Observations to Study Predictors of Events in the Coronary Tree). Altogether 898 patients with acute myocardial infarction with or without ST-segment elevation who after successful percutaneous coronary intervention had near-infrared spectroscopy and intravascular ultrasound imaging performed. Data on lesion location, plaque burden, and lipid content were collected. Current, former, and nonsmokers were examined regarding the presence of high-risk plaques in both culprit and nonculprit lesions as well as plaque location. High-risk plaque characteristics were defined as a maximum plaque burden (maxPB) of ≥70% and a maximum 4 mm lipid core burden index (maxLCBI4mm) of ≥324.7. Results Out of 886 patients with known smoking history, 32% were smokers, 32% former, and 37% nonsmokers. Smokers were younger (median age: smokers 59.0; former 65.5; nonsmokers 64.0 years, p<0.001) with fewer co-morbidities and presented more often with STEMI (% presenting with STEMI: smokers 22.2%; former 18.9%; nonsmokers 19.4%, p=0.006). LDL was similar but CRP was higher in smokers (median µg/mL: smokers 4.0; former 3.1; nonsmokers 2.9, p=0.004). In multivariate models of nonculprit lesion morphology smoking history was not associated with maxPB or maxLCBI4mm but was associated with presence of calcified nodules (OR: 2.88 (95% CI 1.46–5.69) p=0.002 [smokers vs nonsmokers]). Calcified nodules were also associated with number of years smoked (OR: 1.02 (95% CI 1.01–1.03) p=0.004). Smoking was not associated with presence of ≥1 lesions with MaxLCBI4mm, ≥ 324.7, maxPB >=70% or the combination of both. Smoking was not associated with presence of plaque rupture or thrombus. Right coronary artery culprit lesions were more common in smokers and former smokers (smokers 29.9%; former 30.9%; nonsmokers 21.6%; OR: 1.12 (95% CI 1.04–1.21) p<0.001 [smokers vs nonsmokers]). Conclusion In this prospective intracoronary multimodality imaging study of patients with recent acute myocardial infarction, smoking was not associated with a higher rate of high-risk nonculprit plaques based on lipid content by NIRS or PB by IVUS when compared to former or nonsmokers. However, smoking was associated with higher presence of IVUS-detected calcified nodules, higher CRP-levels, and the right coronary artery as it angiographically was a more common site for culprit lesions. These results indicate that the elevated risk in smokers is unrelated to vulnerable plaque morphology defined by high PB and lipid content, and instead possibly related to inflammation, calcification, or hemodynamic changes.Table 1

Very short-term effects of single dose of proprotein convertase subtilisin kexin 9 inhibitor therapy before percutaneous coronary intervention

Abstract Introduction Several pioneering studies have reported that continuous administration of proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitor reduces cardiovascular events and plaque volume on intravascular ultrasound and increase the thickness of the fibrous-cap on optical coherence tomography after 52-76 weeks.[1,2] However, the effect of PCSK9 inhibitors in very short period of time has not adequately been evaluated. Purpose This study aimed to investigate the effect of the single dose of PCSK9 inhibitor in regard to serial change of plaque composition in very short period with near-infrared spectroscopy with intravascular ultrasound (NIRS-IVUS). Methods This prospective, single arm, single-center, interventional study included 27 consecutive coronary artery disease patients (silent myocardial ischemia and stable angina) who performed NIRS-IVUS at the time of coronary angiography for diagnosis between June 2021 and August 2023. Maximal lipid-core burden index over any 4-mm segment (max-LCBI4mm) and total lipid-core burden index (T-LCBI) at the target lesions were assessed with NIRS-IVUS and they were administered evolocumab 420mg. After 2 to 6 weeks, percutaneous coronary intervention (PCI) was performed on a standby basis and repeat NIRS-IVUS were performed at PCI. Results The median max-LCBI4mm showed a significant decrease from 387 to 315 (IQR: 268 to 572 and IQR: 221 to 488, respectively; p = 0.02) in a lesion-wise analysis. The median T-LCBI also showed a significant decrease from 160 to 117 (IQR: 105 to 263 and IQR: 65 to 226, respectively; p = 0.02). Minimum lumen area and minimum lumen diameter showed no significant changes. Conclusions Single dose of PCSK9 inhibitor therapy before PCI resulted in significant degression of lipid core plaques identified by NIRS at the target lesion in very short period of time.Changes of max-LCBI4mmChanges of T-LCBI

Body mass index as a contributor to the accumulation of lipidic plaque materials in statin-treated type 2 diabetic patients with coronary artery disease: sub-analysis from the OPTIMAL randomized study

Abstract Background Patients with type 2 diabetes mellitus more likely exhibit obesity. Pathophysiologically, obesity promotes a range of metabolic disturbances including insulin resistance, dyslipidemia and hypertension, in addition to the secretion of adipokines and pro-inflammatory cytokines from excessive fat accumulation. These atherogenic features may promote instability of atherosclerotic plaques, which ultimately result in elevating a risk of atherosclerotic cardiovascular disease. However, it remains to be fully elucidated how obesity affects atherosclerotic plaque features in type 2 diabetic patients with coronary artery disease (CAD). Near-infrared spectroscopy (NIRS) imaging enables to quantitatively visualize lipidic plaque materials in vivo. This imaging modality provides insights into lipidic plaque features in obese patients with type 2 diabetes mellitus. Purpose To elucidate the association of body mass index (BMI, kg/m2) with lipidic plaque materials in type 2 diabetic patients. Methods The OPTIMAL study was a prospective randomized controlled trial to evaluate the efficacy of continuous glucose monitoring (CGM) guided glycemic control on coronary atherosclerosis in statin-treated type 2 diabetic participants with CAD requiring PCI. 94 patients were randomized into CGM-guided or HbA1c-guided glycemic control. Serial NIRS imaging was conducted to monitor non-culprit lesions at baseline and week 48. The current sub-analysis included 78 patients with both baseline BMI data and evaluable baseline NIRS/IVUS images. Results All of study subjects received a statin (high-intensity statin use=36%), and the averaged LDL-C level was 86.7±26.3 mg/dL. The average BMI and HbA1c level were 24.7±3.1 kg/m2 and 7.5±0.9%, respectively (Table 1). On NIRS imaging analysis, maxLCBI4mm at non-culprit lesions was 286.2±167.0, and 21.8% of study subjects exhibited maxLCBI4mm >400 (Table 2). BMI was associated with maxLCBI4mm (p<0.001). Multivariate analysis adjusting clinical characteristics and LDL-C demonstrated that BMI was an independent contributor to maxLCBI4mm [estimate=17.15 (12.88-21.42), p<0.001] (Table 2). Even in patients receiving high-intensity statin, BMI was still associated with maxLCBI4mm (p<0.001). Conclusions A greater accumulation of lipidic plaque materials was observed in association with BMI in statin-treated type 2 diabetic patients with CAD. This presence of enhanced plaque vulnerability at non-culprit lesions, in the setting of obesity, may contribute to an increased risk of cardiovascular events in type 2 diabetic patients with CAD. The current finding suggests the need to adopt further therapeutic approaches to favourably modify plaque vulnerability in type 2 diabetic patients exhibiting obesity.Table 1:Clinical DemographicsTable 2:Factors Associated with maxLCBI

Lesion-level changes induced by low-density lipoprotein cholesterol lowering therapy in patients with acute myocardial infarction: the pre-specified PACMAN-AMI lesion-level analysis

Abstract Background Previous intracoronary imaging studies investigated atherosclerotic changes induced by lipid-lowering therapy in extensive coronary segments, based on anatomical landmarks and irrespective of the baseline atheroma burden. The effects of lipid-lowering therapy focusing on coronary lesions with advanced atherosclerotic features and at presumably higher risk for future events remains largely unknown. Purpose To provide a lesion-level analysis reporting changes in high-risk atherosclerotic features and plaque phenotypes induced by alirocumab versus placebo in addition to high-intensity statin therapy in nonculprit coronary lesions of patients admitted with acute myocardial infarction (AMI). Methods In this pre-specified lesion-level analysis of the PACMAN-AMI trial, coronary lesions were identified as segments with plaque burden ≥40% defined by intravascular ultrasound (IVUS). IVUS, near-infrared spectroscopy (NIRS) and optical coherence tomography (OCT) images at baseline and 52-week follow-up were manually matched and lesion-level imaging outcome measures were calculated by analysts blinded to treatment allocation and patient clinical data. The evolution of high-risk plaque phenotypes as defined by each imaging modality (IVUS-defined plaque burden ≥70%, NIRS-defined maximum LCBI 4 mm ≥400, OCT-defined thin-cap fibroatheroma <65µm) was investigated. Results Overall, 591 lesions with available baseline and follow-up imaging were included. Of these, 287 were identified in 118 patients (214 vessels) in the alirocumab arm, and 304 lesions were identified in 127 patients (239 vessels) in the placebo arm. At lesion-level, mean change in percent atheroma volume (PAV) by IVUS was -4.86% with alirocumab vs -2.78% with placebo (difference, -2.02 [-3.00 to -1.05], p<.001), substantially greater than that at vessel-level (Figure 1). At the minimum lumen area (MLA) site, mean change in PAV was -10.14% with alirocumab vs -6.70% with placebo (difference, -3.36 (-4.98 to -1.75, p<0.001). MLA increased by 0.15 mm2 with alirocumab and decreased by 0.07 mm2 in the placebo arm (difference, +0.21, 0.01 to 0.41, p=0.036), whereas arterial remodeling was similar between arms (-0.73±1.61 in alirocumab vs -0.63±1.31 in placebo group, p=0.482). Among lesions with high-risk plaque phenotypes at baseline, those in the alirocumab arm more frequently showed a more stable and less lipid-rich plaque phenotype at follow-up than those in the placebo arm (Figure 2). Conclusions At lesion-level, intense lipid-lowering therapy with alirocumab in addition to high-intensity statin therapy induced extensive PAV regression, substantially greater than described in previous vessel-level analyses. Compared to statin therapy alone, alirocumab treatment was associated with a greater enlargement of the lesion MLA, similar negative arterial remodeling, and a more frequent transition of high-risk plaque phenotypes into more stable, less lipid-rich plaque phenotypes.Figure 1.Figure 2

Rapid Prediction of Moisture and Ash Content in Sungkai Leaves Herbal Tea (Peronema canescens Jack.) using NIR Spectroscopy

It is imperative to measure the chemical composition of Sungkai leaf herbal tea in order to produce high-quality goods that promote human health. The moisture and ash content of Sungkai leaf herbal tea are critical parameters for assessing the quality of herbal tea. This study aimed to evaluate an NIR spectroscopy method for quickly determining the moisture and ash content of Sungkai leaf herbal tea. Sungkai leaf herbal tea has a moisture content between 3.93% and 7.59%, and an ash content between 3.94% and 5.51%. We developed a calibration model using partial least squares (PLS) with several pretreatment methods. We split the data into calibration and prediction sets and performed an internal random cross-validation. A PLS calibration model with Rp2 = 0.86, a root means square error of prediction (RMSEP) of 0.30 (%), and a residual predictive deviation (RPD) of 2.76, performed exceptionally well at predicting the moisture content when the standard normal variate (SNV) pre-treatment was applied to the NIR spectra. The Savitzky-Golay derivative (a 9-point smoothing window, second-order polynomial, dg2) pre-treatment method also generated the best PLS calibration model for ash content determination, with Rp2 = 0.70, RMSEP = 0.16 (%), and RPD = 1.86. NIR spectroscopy can quickly determine the moisture and ash content of Sungkai leaf herbal tea, as suggested by these findings.

Aesthetic evaluation of body movements shaped by embodied and arts experience: Insights from behaviour and fNIRS

Aesthetic appreciation of full-body movements is likely shaped by our cumulative bodily experiences, yet most of the extant literature in this domain has focused on expertise and familiarity. We ran two experiments exploring individual differences in embodied experience and experience with the arts: In Study 1, we explored how participants’ (n = 41) abilities to learn a choreography shaped their aesthetic perceptions while viewing learned vs. unknown movements, using functional near-infrared spectroscopy (fNIRS) to measure cortical activation over the Action Observation Network (i.e., inferior frontal gyrus [IFG], inferior parietal lobule, middle temporal gyrus [MTG]). Study 1 demonstrated that embodied experience enhanced ratings of enjoyment, familiarity, and reproducibility of movements, and that individual differences in participants’ performance of the learned choreography were not associated with aesthetic ratings, but rather cortical activation in IFG and right MTG while viewing learned choreography. In Study 2, we combined the behavioural data from Study 1 with data from additional participants (total n = 141) to examine the relationship between arts experience and aesthetic perceptions of movements robustly. Study 2 revealed that previous arts and sports experience correlated with aesthetic judgements of familiarity and reproducibility of movements. Our findings highlight the relevance of examining individual experiences to fill theoretical gaps in our understanding of action aesthetics.

Evaluation of non-target lesions in femoropopliteal disease using near-infrared spectroscopy intravascular ultrasound imaging

Abstract Aim This study aims to assess the plaque morphology of non-target lesions, especially lipid-core-containing plaque (LCP), and compare it to target lesions using near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) in patients with femoropopliteal disease. Methods We conducted a single-center prospective observational study on 14 patients who underwent endovascular therapy for femoropopliteal disease between July 2022 and November 2023. NIRS-IVUS assessment was performed on the whole femoropopliteal arterial segment. Forty-one LCP lesions > maximum lipid-core burden index in any 4-mm region (max LCBI4mm) 100 were detected by NIRS-IVUS. We evaluated patient and lesion characteristics. In addition, the LCP lesions were divided into two groups, the target lesion group (n=18) and the non-target lesion group (n=23), and compared. Results Patient characteristics were notable for advanced age (76.8±6.6 years), high incidence of male (78.7%), hypertension (100%), dyslipidemia (78.6%), diabetes (64.3%), statin use (71.4%). Lipid profiles were as follows: LDL-cholesterol 85.9±26.7 mg/dl, HDL-cholesterol 48.9±12.7 mg/dl, triglyceride 138.9±80.3 mg/dl, lipoprotein(a) 19.6±16.3 mg/dl. Ten participants had LCPs in the non-target lesion (71.4%). For IVUS findings, the target lesion group had significantly longer lesion length (34.6±11.9 mm vs. 22.6±8.7 mm, p=0.001), smaller minimum lumen area (7.0±2.8 mm2 vs. 14.8±5.4 mm2, p<0.001), and larger plaque burden (78.0±5.0 % vs. 53.0±12.0 %, p<0.001) than those in the non-target lesion group. No significant differences were observed in the prevalence of calcification (target lesion group vs. non-target lesion group: 83.3 % vs. 91.3 %, p=0.64) and the extent of calcification (p=0.76). For NIRS findings, the target lesion group contained a significantly smaller proportion of LCP in the lesion length (25.9±15.7 % vs. 50.6±29.2 %, p=0.002) than the non-target lesion group. On the other hand, there were no significant differences in the value of max LCBI4mm (284.4±153.4 vs. 289.5±113.1, p=0.90) and the length of LCP lesion (9.8±9.7 mm vs. 10.7±6.9 mm, p=0.74) and distribution of LCP (p=0.08) between both groups. In addition, the number of LCPs in the target femoropopliteal artery was positively correlated with max LCBI4mm in the target femoropopliteal artery (r=0.671, p=0.008) Conclusion NIRS-IVUS findings in this study demonstrated that the non-target lesions contained LCPs to the same degree as the target lesions.

The impact of lipid rich plaque on coronary-microvascular-dysfunction evaluated by near-infrared spectroscopy IVUS and angiography-derived index of microcirculatory resistance after percutaneous-coron

Abstract Background Coronary microvascular dysfunction (CMD) after percutaneous coronary intervention (PCI) has been reported to be associated not only with periprocedural myocardial infarction, but also with poor prognosis. While index of microcirculatory resistance using pressure wire (invasive IMR) has been conventionally used to evaluate CMD, angio-derived IMR (angio-IMR) has recently emerged as a noninvasive method and has shown good correlation with invasive IMR. Previous investigations have already shown that the maximum value of LCBI for any of the 4-mm segments (maxLCBI4mm) by near-infrared spectroscopy IVUS (NIRS-IVUS) represents the degree of lipid rich plaque (LRP) and can predict microvascular obstruction after PCI. However, few studies have examined the relationship between maxLCBI4mm values assessed by NIRS-IVUS and the degree of CMD from physiological assessment, or the optimal maxLCBI4mm cut-off values to predict CMD after PCI. Purpose The purpose of this study was to define the relationship between LRP identified by NIRS-IVUS and CMD assessed by angio-IMR in coronary artery disease (CAD) patients and to determinate the optimal diagnostic cut-off values of maxLCBI4mm. Methods We retrospectively evaluated 101 consecutive patients who underwent PCI using NIRS-IVUS for CAD, excluding STEMI, at our hospital from November 2021 to January 2024. MaxLCBI4mm and angio-IMR were measured in culprit vessel before and after PCI. CMD was defined as angio-IMR≥25. ROC curve analysis was performed to determine the optimal cut-off values of maxLCBI4mm for angio-IMR≥25. Plaques with maxLCBI4mm values above the cut-off were defined as the LRP group. Results Of 101 patients, CMD after PCI occurred in 37 patients (37%). MaxLCBI4mm values were significantly higher in the CMD group compared to the non-CMD group (659±198 vs. 403±226, P<0.001). Figure 1 shows the results of ROC analysis for predicting the incidence of CMD after PCI. ROC analysis determined maxLCBI4mm≥579 (LRP group) as an optimal cut-off value associated with incidence of CMD (AUC=0.80, P<0.01, sensitivity=0.78, specificity=0.75). LRP group had significantly higher angio-IMR values and incidence of CMD than non-LRP group (24.7±7.8 vs. 19.1±7.2, P<0.01, 64% vs. 14%, P<0.01). Furthermore, Δangio-IMR (post PCI-Pre PCI) of the LRP group was significantly higher than that of the non-LRP group (Figure 2). On multivariable analysis, maxLCBI4mm≥579 emerged as the independent predictor of the incidence of CMD after PCI (OR=10.6, 95% CI=2.29-48.8, P<0.01). Conclusions The results of this study indicate that NIRS-IVUS-guided PCI is a useful predictor of the incidence of CMD after PCI.Figure 1Figure 2

Comparative Analysis of Milling Technologies in Dark and Milk Cocoa Topping Production for Ice Cream

Chocolate and cocoa toppings are widely used for confectionery products. Toppings used for ice creams contain higher fat content (about 40-60%) to ensure a greater flow to cover the whole product. The dark cocoa topping consists of cocoa and sugar powder distributed in vegetable fat, while cocoa topping with the added 7% non-fat milk fraction is regarded as a milk cocoa topping. This research aimed to determine and compare the impact of the ball mill, and five-roll mill and conching used for the production of dark and milk cocoa toppings regarding the particle size distribution, rheology properties and content of moisture, sucrose, fat and lactose. The obtained results showed that the volume-weighted mean parameter D (4,3) was lower in the samples produced in a ball mill. Additionally, the viscosity, linear and Casson, slightly increased in samples produced in a ball mill except for the milk cocoa topping which had 0.55 fold higher value of linear viscosity compared to the sample produced using a five-roll mill and conching. Regarding the results of NIR spectroscopy, it was found that the samples produced in a ball mill showed higher values of moisture, but lower values of sucrose, lactose and fat.

A Model for Fat Content Detection in Walnuts Based on Near-Infrared Spectroscopy

Near-infrared spectroscopy (NIR) is an efficient and accurate method for fat content detection in walnuts. ‘Wen 185’ walnut is grown in large quantities in southern Xinjiang, and its fat content is an important indicator for evaluating the intrinsic quality. The excessive pursuit of yield efficiency, combined with the neglect of quality, agricultural product safety and other factors, has led to the production of poor-quality walnuts. Moreover, research on predicting walnut kernel fat content based on near-infrared spectroscopy technology is rarely reported. Therefore, a technical framework for walnut kernel detection based on near-infrared spectroscopy and the technical standards for ‘Wen 185’ are urgently needed. After first optimizing the initial spectrum data using five preprocessing methods, we established separate prediction models for walnut kernel fat content based on either a back propagation neural network or a support vector regression (SVR) algorithm. The results show that the correction set and validation set coefficients of determination of the walnut kernel fat content prediction model using the back propagation neural network algorithm were 0.86 and 0.89, respectively, with root mean square errors of 1.56 and 1.58, and an RPD value of 2.57; the coefficients of determination for the calibration and validation sets of SVR were 0.90 and 0.83, respectively, with root mean square errors of 1.76 and 1.70, respectively, and an RPD value of 1.70. Thus, near-infrared spectroscopy can be used to establish a foundation for realizing the rapid detection of walnut kernel fat content.

Tribomechanical characterization of ceramic reinforced composite coatings for modification of cylinder liner of heavy-duty diesel engines

Heavy-duty diesel engines are essential mechanic power generation tools for industry and transporting freight and passengers. Therefore, increasing engine efficiency and minimizing maintenance and repair costs is crucial. This study examines and characterizes three thermal spray coatings (Cr3C2/NiCr, NiCr, and Al2O3/TiO2) utilized on cylindrical gray cast iron substrate specimens. The coatings were tested for their microstructural (optical microstructure, SEM, EDS, XRD, and AFM topography), mechanical (nanoindentation and nano scratch), and tribological (short and long-distance wear test) properties. Microstructural tests showed that an average coating thickness of 120 to 170 µm was successfully achieved on the cast iron base substrate using different thermal coating methods. The Cr3C2/NiCr coating, observed through the AFM mapping method, achieved the most uniform roughness distribution on the surface. The elasticity of the coatings was measured with a nanoindentation test, and Al2O3/TiO2 coating exhibited high rigidness (177 GPa). The nano scratch test showed that the highest load-carrying capacity was achieved with the Cr3C2/NiCr coated sample. NiCr-coated sample exhibited approximately similar rigidness (61 GPa) to cast iron (67 GPa). Short- and long-distance wear tests showed that the coatings provided significantly better wear resistance than the cast iron base. The coatings’ efficacy was evident. At the long-distance tests, while the cast iron base sample had a wear rate of 19.874 (10−7mm3/Nm), the wear rates of Al2O3/TiO2, Cr3C2/NiCr, and NiCr coatings were 3.835, 4.020, and 6.466 (10−7mm3/Nm), respectively. The Al2O3/TiO2 and Cr3C2/NiCr coatings had superior tribological performance than the NiCr coating, yet the NiCr coating showed much higher wear performance than the uncoated base. The Cr3C2/NiCr coating exhibited superior tribomechanical performance in all the coatings.