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In vehicular ad hoc networks, attackers can disguise as replicas of legitimate vehicles by cracking or colluding and then use the identity replicas in a malicious way. Not only the generation of replicas itself poses an aggressive behavior, but also the replicas can enable other insider attacks, such as denial of service, information interception, and replay attack. To solve this issue, researchers have presented many solutions in wireless sensor network or in mobile ad hoc networks. However, majority of current schemes are not good at dealing with conspiracy replicas or lack of considering peculiar characteristics of high mobility of vehicles. For detecting identity replicas in vehicular ad hoc networks, we propose a detection method with sequential trajectory segment based on semi-supervised support vector machine. In terms of semi-supervised support vector machine, we establish a detection model using spatio-temporal trajectories of different identities as input samples, which include features of both conspiracy and non-conspiracy attack scenarios. To validate our approach, we apply sequential trajectory segment to simulation environment. The performance analysis and experimental studies suggest that our proposed method provides high detection accuracy, which is almost impervious to the replica identity ratios in vehicular ad hoc networks. Furthermore, the time performance of replica detection is less affected by the distance between compromised nodes and their clones than that of existing solutions.

Sustained release of anesthesia has shown great promise in the treatment of chronic pain in patients. In this research, we used neutralized ropivacaine as an anesthesia and poly(ε-caprolactone) (PCL) with different architectures to systematically study how these architectures affect the release of ropivacaine. After optimizing the parameters of the preparation of microspheres, ropivacaine-loaded 1-PCL microspheres and 4-PCL microspheres were obtained. Fourier Transform infrared spectra (FT-IR) and X-ray diffraction spectra (XRD) confirmed that ropivacaine was encapsulated within the microsphere rather than inserted on the surface of the microsphere. Ropivacaine was found to be buried deeper in the 1-PCL microsphere than in the 4-PCL microsphere. In vitro release assay revealed that small crystalline grains interfered with ropivacaine release in 4-PCL microspheres during the initial release period, but then two kinds of microspheres showed a similar ropivacaine release rate. We basically proved that the architecture of PCL has a negligible effect on ropivacaine release. Cell proliferation test revealed that the release of products from the microspheres resulted in insignificant toxicity towards mammalian cells.

Objective. The present study aimed to explore the association between SUA and NAFLD in women with different menstrual statuses. Methods. A total of 6043 women were selected from the Jidong and Kailuan communities for inclusion in the present study. The SUA levels of participants were divided into quartiles. NAFLD was determined by abdominal ultrasonography. Data from laboratory tests and clinical examination were collected, and basic information was obtained from standardized questionnaires. The menstrual status was stratified into menstrual period, menopause transition period, and postmenopause. Multivariate logistic regression models were used to determine the relationship between menstrual status, SUA, and NAFLD. Results. The levels of SUA in subjects with NAFLD in the menstrual period, menopause transition period, and postmenopause were 268.0 ± 71.1, 265.6 ± 67.8, and 286.7 ± 75.8 (mmol/L), respectively, and were higher than those in subjects without NAFLD. The adjusted odds ratios (ORs) with 95% confidence interval (CI) for NAFLD among participants in the menopause transition period and postmenopausal period were 1.10 (0.89–1.37) and 1.28 (1.04–1.58), respectively, compared with the menstrual period women. Compared to the lowest quartile of SUA, the adjusted ORs with 95% CI of the highest quartile for NAFLD were 2.24 (1.69–2.99) for females in the menstrual period, 1.92 (1.10–3.37) for females in the menopause transition period, and 1.47 (1.06–2.03) for females in postmenopause. Conclusions. Menstrual status was significantly correlated with NAFLD. High levels of SUA were associated with NAFLD in females during the three menstrual periods.

Depression is a common comorbidity in Parkinson's disease (PD) but is underdiagnosed. We aim to investigate the altered metabolic pathways of Parkinson's disease-related depression (PDD) in plasma and to identify potential biomarkers for clinical diagnosis. Consecutive patients with PD were recruited, clinically assessed, and patients with PDD identified. Fasting plasma samples were collected from 99 patients and differentially expressed metabolites and proteins between patients with PDD and PD were identified using non-targeted liquid chromatography-mass spectrometry (LC-MS)-based metabolomics and tandem mass tag (TMT)-based proteomics analysis, followed by an integrated analysis. Based on the above results, enzyme-linked immune sorbent assay (ELISA) tests were then performed to identify potential biomarkers for PDD. In clinics, patients with PDD suffered less hypertension and had lower serum low-density lipoprotein cholesterol and apolipoprotein B levels when compared to the other patients with PD. A total of 85 differentially expressed metabolites were identified in metabolomics analysis. These metabolites were mainly lipids and lipid-like molecules, involved in lipid and glucose metabolic pathways. According to proteomics analysis, 17 differentially expressed proteins were identified, and 12 metabolic pathways were enriched, which were predominantly related to glucose metabolism. Integrated analysis indicated that altered lipid and glucose metabolism in PDD may induce cellular injury through oxidative stress. Additionally, plasma levels of several proteins were confirmed to be significantly altered and correlated with depressive severity. NOTCH2 may be a potential blood biomarker for PDD, with an optimal cut-off point of 0.91 ng/ml, a sensitivity value of 95.65%, and a specificity value of 81.58%. Depressive symptoms are associated with lipid and glucose metabolism in patients with PD and NOTCH2 may be a potential blood biomarker for the clinical diagnosis of PDD.

Panax notoginseng (P. notoginseng) has excellent medicinal and food dual-use characteristics. However, P. notoginseng with a unique origin label has become the target of fraud because of people confusing or hiding its origin. In this study, an untargeted nuclear magnetic resonance (NMR)-based metabolomics approach was used to discriminate the geographical origins of P. notoginseng from four major producing areas in China. Fifty-two components, including various saccharides, amino acids, saponins, organic acids, and alcohols, were identified and quantified through the NMR spectrum, and the area-specific geographical identification components were further screened. P. notoginseng from Yunnan had strong hypoglycemic and cardiovascular protective effects due to its high acetic acid, dopamine, and serine content, while P. notoginseng from Sichuan was more beneficial for diseases of the nervous system because of its high content of fumarate. P. notoginseng from Guizhou and Tibet had high contents of malic acid, notoginsenoside R1, and amino acids. Our results can help to distinguish the geographical origin of P. notoginseng and are readily available for nutritional recommendations in human consumption. [ABSTRACT FROM AUTHOR]

Simple Summary: The liver function reserve of patients with hepatocellular carcinoma (HCC) is heterogeneous. The preoperative accurate evaluation of liver function has a vital role in the prevention of unfavorable postoperative complications such as post-hepatectomy liver failure. In this study, unsupervised clustering analysis of radiomics features extracted from preoperative gadoxetic-acid-enhanced MRIs was performed for liver function stratification on 276 HCC patients. Two distinct subgroups were identified (i.e., subgroups 1 and 2). Subgroup 2 had impaired liver function as presented by older age, more albumin–bilirubin grades 2 and 3, and a higher indocyanine green retention rate than that of subgroup 1 (all p < 0.05). Compared with subgroup 1, subgroup 2 was associated with a higher risk of postoperative liver failure, postoperative complications, and longer hospital stays (all p < 0.05). Our findings indicate the potential for the use of radiomics features based on preoperative gadoxetic-acid-enhanced MRI for noninvasive liver function assessment in HCC patients. Objective: To identify subgroups of patients with hepatocellular carcinoma (HCC) with different liver function reserves using an unsupervised machine-learning approach on the radiomics features from preoperative gadoxetic-acid-enhanced MRIs and to evaluate their association with the risk of post-hepatectomy liver failure (PHLF). Methods: Clinical data from 276 consecutive HCC patients who underwent liver resections between January 2017 and March 2019 were retrospectively collected. Radiomics features were extracted from the non-tumorous liver tissue at the gadoxetic-acid-enhanced hepatobiliary phase MRI. The reproducible and non-redundant features were selected for consensus clustering analysis to detect distinct subgroups. After that, clinical variables were compared between the identified subgroups to evaluate the clustering efficacy. The liver function reserve of the subgroups was compared and the correlations between the subgroups and PHLF, postoperative complications, and length of hospital stay were evaluated. Results: A total of 107 radiomics features were extracted and 37 were selected for unsupervised clustering analysis, which identified two distinct subgroups (138 patients in each subgroup). Compared with subgroup 1, subgroup 2 had significantly more patients with older age, albumin–bilirubin grades 2 and 3, a higher indocyanine green retention rate, and a lower indocyanine green plasma disappearance rate (all p < 0.05). Subgroup 2 was also associated with a higher risk of PHLF, postoperative complications, and longer hospital stays (>18 days) than that of subgroup 1, with an odds ratio of 2.83 (95% CI: 1.58–5.23), 2.41(95% CI: 1.15–5.35), and 2.14 (95% CI: 1.32–3.47), respectively. The odds ratio of our method was similar to the albumin–bilirubin grade for postoperative complications and length of hospital stay (2.41 vs. 2.29 and 2.14 vs. 2.16, respectively), but was inferior for PHLF (2.83 vs. 4.55). Conclusions: Based on the radiomics features of gadoxetic-acid-enhanced MRI, unsupervised clustering analysis identified two distinct subgroups with different liver function reserves and risks of PHLF in HCC patients. Future studies are required to validate our findings. [ABSTRACT FROM AUTHOR]

Background: Epidural clonidine improves analgesia but may induce adverse effects in labor. Objective: To evaluate the efficacy and safety of epidural clonidine as local anesthetics (LA) adjuvant by continuous infusion or patient‐controlled epidural analgesia (PCEA) in labor. Search Strategy: PubMed, Embase, Web of Science, and CENTRAL were searched from inception to May 10, 2022 without language restriction; references of the retrieved studies were hand searched. Selection Criteria: Randomized controlled trials (RCTs) comparing epidural LA with and without clonidine using continuous infusion or PCEA in labor were included. Data Collection and Analysis: A random effects model was used to pool the data on analgesia and adverse effects. Main Results: Eight RCTs were included. Clonidine did not reduce the incidence of parturients requiring additional epidural boluses but reduced LA consumption and pain scores without increasing adverse effects, except for a higher incidence of instrumental delivery when clonidine was combined with LA and opioid (risk ratio 2.38, 95% confidence interval 1.26–4.50). Clonidine offered similar analgesia to opioids but had reduced opioid‐related adverse effects. Trial sequential analysis showed that the evidence was insufficient. Conclusions: Epidural clonidine by continuous infusion or PCEA does not increase significant adverse effects and offers similar analgesia to opioids in labor. PROSPERO registration no. CRD42022306565. Synopsis: Epidural clonidine by continuous infusion or patient‐controlled analgesia provides analgesia similar to opioids without significantly increasing maternal and neonatal adverse effects in labor. [ABSTRACT FROM AUTHOR]

Warm-sector heavy rainfall (WR), shear-line heavy rainfall (SR), and frontal heavy rainfall (FR) are three types of rainfall that frequently occur during the pre-summer rainy season in south China. In this research, we investigated the differences in microphysical characteristics of heavy rainfall events during the period of 10-15 May 2022 based on the combined observations from 11 S-band polarimetric radars in south China. The conclusions are as follows: (1) WR has the highest radar echo top height, the strongest radar echo at all altitudes, the highest lightning density, and the most active ice-phase process, which suggests that the convection is the most vigorous in the WR, moderate in the FR, and the weakest in the SR. (2) Three types of rainfall are all marine-type precipitation, the massweighted mean diameter (Dm, mm) and the intercept parameter (Nw, mm-1m-3) of the raindrops in the WR are the largest. (3) The WR possesses the highest proportion of graupel compared with the FR and SR, and stronger updrafts and more abundant water vapor supply may lead to larger raindrops during the melting and collision-coalescence processes. (4) Over all the heights, liquid and ice water content in the WR are higher than those in the SR and FR, the ratio of ice to liquid water content in the WR is as high as 27% when ZH exceeds 50 dBZ, definitely higher than that in the SR and FR, indicating that the active ice-phase process existing in the WR is conducive to the formation of heavy rainfall. [ABSTRACT FROM AUTHOR]

X-band dual-polarization phased array radar (XPAR-D) possesses high resolution and plays a significant role in detecting meso- and micro-scale convective systems. However, the precipitation attenuation it endures necessitates an effective correction method. This study selected radar data from XPAR-D at the peak of Maofeng Mountain in Guangzhou during 16–17 May 2020 from three precipitation stages after quality control. Attenuation coefficients were calculated for different precipitation types through scattering simulations of raindrop size distribution (RSD) data. Next, an attenuation correction algorithm (MZH-KDP method) was proposed for the radar reflectivity factor (ZH) according to different raindrop types and compared to the ZH-KDP method currently in use. The results indicate that the attenuation amount of XPAR-D echoes depends on the attenuation path and echo intensity. When the attenuation path is shorter and the echo intensity is weaker, the amount of attenuation and correction is smaller. Difficulties arise when there are noticeable deviations, which are challenging to resolve using attenuation correction methods. Longer attenuation paths and stronger echoes highlight the advantages of the MZH-KDP method, while the ZH-KDP method tends to overcorrect the bias. The MZH-KDP method outperforms the ZH-KDP method for different precipitation types. The superior correction capability of the MZH-KDP method provides a significant advantage in improving the performance of XPAR-D for the detection of extreme weather. [ABSTRACT FROM AUTHOR]

Polarimetric radar data are an important tool for quantitative precipitation estimation (QPE), which is essential for monitoring and forecasting precipitation. Previous studies have shown that the drop size distribution (DSD) and polarimetric radar parameters of typhoon-induced precipitation differ significantly from those of other types of rainfall. South China is a region that frequently experiences typhoons and heavy rainfall, which can cause serious disasters. Therefore, it is critical to develop a QPE algorithm that is suitable for typhoon precipitation over South China. In this study, we constructed four simple QPE estimators, R(ZH), R(ZH, ZDR), R(KDP) and R(KDP, ZDR) based on two-dimensional video disdrometer (2DVD) DSD observations of typhoon-induced precipitation over South China in 2017–2018. We analyzed the DSD characteristics and the estimation accuracy of these four QPE estimators in the reflectivity–differential reflectivity (ZH–ZDR) space, as well as the S-band polarimetric radar (S-POL) data of seven typhoon-induced precipitation events that affected South China in 2017–2019. We used these data to quantitatively determine the optimal ranges of the estimators and establish a typhoon precipitation QPE algorithm for typhoon-induced precipitation over South China (2DVD-Typhoon). The evaluation results showed that: (1) compared to R(ZH) and R(KDP), R(ZH, ZDR) and R(KDP, ZDR) had lower performance in estimating typhoon-induced rainfall after incorporating the polarimetric parameter ZDR, as strong crosswind of the typhoon caused some bias in the raindrop-induced ZDR; (2) the 2DVD-Typhoon algorithm utilizes the respective advantages of the individual estimators to generate the best QPE results; (3) the QPE performance of 2DVD-Typhoon and the Colorado State University–Hydrometeor Identification Rainfall Optimization (CSU-HIDRO) is used as a comparison for hourly rainfall, cumulative rainfall and different rainfall intensity. The comparison shows that 2DVD-Typhoon gives a better normalized error (NE), root mean square error (RMSE) and correlation coefficient (CC), indicating its strength in rainfall estimation for typhoons over South China. The above results provide theoretical support for improving typhoon-induced rainfall monitoring and numerical weather forecasting models in South China. [ABSTRACT FROM AUTHOR]

Based on ERA5 reanalysis data and multi-source observations, including polarimetric radar and automatic weather stations, this study analyzes the formation mechanism and microphysical characteristics of a warm-sector heavy rainfall event caused by a convective system with multiple-rain-bands organizational mode over the western coast of south China. In the early stage, under the influence of coastal convergence and topography, convection was triggered in the coastal mountainous areas and moved north-eastwards. Nocturnal cooling induced the north winds in the inland mountainous area. A mesoscale convergence line was formed in the middle of Yangjiang city between the inland north and coastal south winds, which facilitated the developing and merging of convective storms into a linear convective band along the convergence line. This relatively long convective band presented a quasi-stationary state in the south of Mt. Ehuangzhang and Mt. Tianlu, which results in the first precipitation peak. At this stage, the convection developed to a higher level, with relatively larger raindrops, producing larger amounts of rainfall, which was probably related to the active merging of convection. In the later phase, as the environmental winds shifted, convective bands tended to move southeastwards, accompanied with the cold pools. At the same time, the multiple short convective bands were formed, which were almost parallel to the shear line, and a multiple-rain-bands organizational mode occurred. The mesoscale convergence line maintained due to the outflows of cold pools caused by precipitation in the preceding period, and then gradually moved southwards. Under the influence of the mesoscale convergence and topography, convection was continuously triggered at the southern end of the short convective bands. This back-building characteristic favored the development of the convective system. The multiple rain bands passed through the same place in a "rainband-training" form, resulting in the second peak of precipitation. The collision process was active in the low levels during this event. [ABSTRACT FROM AUTHOR]

BACKGROUND: The market demand for Panax notoginseng (P. notoginseng) is growing rapidly because of its useful properties in food and medicine. However, the frequent adulteration of P. notoginseng seriously affects the health of consumers and is a great challenge to food safety. In this study, low‐ and high‐field nuclear magnetic resonance (LF/HF‐NMR) were applied to detect the transverse relaxation distribution of P. notoginseng contaminated with different ratios of Caulis clematidis armandii (CCA) and the components in P. notoginseng and CCA, respectively. RESULTS: Fifty‐seven kinds of major and minor components in P. notoginseng and CCA were identified and quantified from their high‐resolution NMR spectra, and there were significant differences in ginsenosides, sucrose, and glucose between P. notoginseng and CCA. Furthermore, the partial least squares regression analysis results indicated that LF‐NMR parameters (T21 and S21) changed linearly as the ratio of CCA increased, and these changes were attributed to the variations in polysaccharide and sucrose in adulterated P. notoginseng. CONCLUSION: In the relaxation time‐based pattern recognition models, the authentic P. notoginseng powder could be classified with 100% accuracy from adulterated P. notoginseng when the adulteration ratio was greater than 30%, demonstrating the possibility of LF‐NMR, in combination with pattern recognition, for rapid discrimination of food authenticity. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A temperature sensor based on composite multicavity Fabry-Perot interferometers (FPIs) and a sensitivity-enhanced differential phase demodulation method is proposed and demonstrated. The structure was fabricated by partially filled polydimethylsiloxane (PDMS) into a segment of hollow-core fiber (HCF) which is spliced with a single-mode fiber (SMF). In this structure, composite multicavity FPIs are formed, including an air-cavity FPI, a PDMS-cavity FPI and an air-PDMS cavity FPI. The contribution of the different FPIs to the superimposed spectrum is analyzed from the simulated and experimental perspectives. The results demonstrate that the superimposed output spectrum is mainly produced by the air-cavity FPI and the air-PDMS cavity FPI. When the temperature increases, the lengths of the PDMS-cavity and the air-PDMS cavity are enhanced due to the volume expansion of PDMS, and the length of the air-cavity decreases because the air-cavity is compressed by the expanded PDMS. The cavity length variation causes the phase variation in the air-cavity FPI to be the opposite to that in the PDMS-cavity FPI or air-PDMS cavity FPI. Therefore, the phase demodulation sensitivity is enhanced by calculating the differential phase between the air-cavity FPI and the air-PDMS cavity FPI. The experimental results show that the sensitivity amplification factor of differential phase to the single phase of the air-cavity FPI or the air-PDMS cavity FPI is from approximately 1.44–3.25. This phase demodulation method is simpler, faster, more direct, and more convenient than wavelength demodulation from the perspective of demodulating composite interferometers. [ABSTRACT FROM AUTHOR]

Carboxylesterase is a multifunctional superfamily and can be found in almost all living organisms. As the metabolic enzymes, carboxylesterases are involved in insecticides resistance in insects for long time. In our previous studies, the enhanced carboxylesterase activities were found in the chlorantraniliprole resistance strain of diamondback moth (DBM). However, the related enzyme gene of chlorantraniliprole resistance has not been clear in this strain. Here, a full-length cDNA of carboxylesterase pxCCE016b was cloned and exogenously expressed in Escherichia coli at the first time, which contained a 1693 bp open reading frame (ORF) and encoded a protein of 542 amino acids. Sequence analysis showed that this cDNA has a predicted mass of 61.56 kDa and a theoretical isoelectric point value of 5.78. The sequence of deduced amino acid possessed the classical structural features: a type-B carboxylesterase signature 2 (EDCLYLNVYTK), a type-B carboxylesterase serine active site (FGGDPENITIFGESAG) and the catalytic triad (Ser186, Glu316, and His444). The real-time quantitative PCR (qPCR) analysis showed that the expression level of the pxCCE016b was significantly higher in the chlorantraniliprole resistant strain than in the susceptible strain. Furthermore, pxCCE016b was highly expressed in the midgut and epidermis of the DBM larvae. When the 3rd-instar larvae of resistant DBM were exposed to abamectin, alpha-cypermethrin, chlorantraniliprole, spinosad, chlorfenapyr and indoxacarb insecticides, the up-regulated expression of pxCCE016b was observed only in the group treated by chlorantraniliprole. In addition, recombinant vector pET-pxCCE016b was constructed with the most coding region (1 293 bp) and large number of soluble recombinant proteins (less than 48 kDa) were expressed successfully with prokaryotic cell. Western blot analysis showed that it was coded by pxCCE016b. All the above findings provide important information for further functional study, although we are uncertainty whether the pxCCE016b gene is actually involved in chlorantraniliprole resistance.

The minimization of polarization multiplexing angle in a polarization-division-multiplexed (PDM) transmission system is explored. An effective polarization demultiplexing algorithm based on Stokes space is proposed to realize the demultiplexing of two nonorthogonal polarization states. Both simulation and experimental results verify the effectiveness of the proposed algorithm for the transmission of a 56-Gb/s PDM-dual phase-shift keying (DPSK) signal over different polarization multiplexing angles (i.e., θ 1/4 23°, 45°, 67°, 90°) and different lengths of transmission links (i.e., back-to-back, 320 km, 400 km).

Shuidouchi (Natto) is a fermented soy product showing in vivo gastric injury preventive effects. The treatment effects of Shuidouchi fermented in different vessels on HCl/ethanol-induced gastric mucosal injury mice through their antioxidant effect was determined. Shuidouchi contained isoflavones (daidzein and genistein), and GVFS (glass vessel fermented Shuidouchi) had the highest isoflavone levels among Shuidouchi samples fermented in different vessels. After treatment with GVFS, the gastric mucosal injury was reduced as compared to the control mice. The gastric secretion volume (0.47 mL) and pH of gastric juice (3.1) of GVFS treated gastric mucosal injury mice were close to those of ranitidine-treated mice and normal mice. Shuidouchi could decrease serum motilin (MTL), gastrin (Gas) level and increase somatostatin (SS), vasoactive intestinal peptide (VIP) level, and GVFS showed the strongest effects. GVFS showed lower IL-6, IL-12, TNF-α and IFN-γ cytokine levels than other vessel fermented Shuidouchi samples, and these levels were higher than those of ranitidine-treated mice and normal mice. GVFS also had higher superoxide dismutase (SOD), nitric oxide (NO) and malonaldehyde (MDA) contents in gastric tissues than other Shuidouchi samples. Shuidouchi could raise IκB-α, EGF, EGFR, nNOS, eNOS, Mn-SOD, Gu/Zn-SOD, CAT mRNA expressions and reduce NF-κB, COX-2, iNOS expressions as compared to the control mice. GVFS showed the best treatment effects for gastric mucosal injuries, suggesting that glass vessels could be used for Shuidouchi fermentation in functional food manufacturing.

Innovative human immunodeficiency virus (HIV) testing services will be needed to achieve the first 90 (90% of HIV-positive persons aware of their infection status) of the 90-90-90 target in China. Here, we describe an internet-based urine delivery testing service delivered through three pilot drugstores in Beijing that send specimens to a designated laboratory for HIV. From May 2016 to January 2017, we provided 500 HIV urine-testing service packs for display at the drugstores, and a total of 430 (86.0%) urine specimens were mailed back. All of the 430 urine specimens were of good quality and were tested. 70 urine specimens were HIV positive, showing a 16.3% (70/430) positivity rate. A total of 94.3% (66/70) of the HIV-positive participants obtained their test results through the internet, and 69.7% (46/66) of these participants received follow-up care. A total of 40 out of 46 (87.0%) participants agreed to have their results confirmed by a blood test, and 39 out of 40 (97.5%) participants were confirmed as HIV-1 positive, including two individuals that were previously diagnosed. Lastly, 28 out of 37 (75.7%) of the study participants were referred to the hospital and provided free antiviral treatment. Our data indicate that this innovative HIV testing service is effective and play an important role in HIV testing and surveillance.