Displaying publications 1 - 20 of 61 in total

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  1. Zakaria A, Shakaff AY, Masnan MJ, Saad FS, Adom AH, Ahmad MN, et al.
    Sensors (Basel), 2012;12(5):6023-48.
    PMID: 22778629 DOI: 10.3390/s120506023
    In recent years, there have been a number of reported studies on the use of non-destructive techniques to evaluate and determine mango maturity and ripeness levels. However, most of these reported works were conducted using single-modality sensing systems, either using an electronic nose, acoustics or other non-destructive measurements. This paper presents the work on the classification of mangoes (Magnifera Indica cv. Harumanis) maturity and ripeness levels using fusion of the data of an electronic nose and an acoustic sensor. Three groups of samples each from two different harvesting times (week 7 and week 8) were evaluated by the e-nose and then followed by the acoustic sensor. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were able to discriminate the mango harvested at week 7 and week 8 based solely on the aroma and volatile gases released from the mangoes. However, when six different groups of different maturity and ripeness levels were combined in one classification analysis, both PCA and LDA were unable to discriminate the age difference of the Harumanis mangoes. Instead of six different groups, only four were observed using the LDA, while PCA showed only two distinct groups. By applying a low level data fusion technique on the e-nose and acoustic data, the classification for maturity and ripeness levels using LDA was improved. However, no significant improvement was observed using PCA with data fusion technique. Further work using a hybrid LDA-Competitive Learning Neural Network was performed to validate the fusion technique and classify the samples. It was found that the LDA-CLNN was also improved significantly when data fusion was applied.
    Matched MeSH terms: Odors*
  2. Idris NF, Le-Minh N, Hayes JE, Stuetz RM
    J Environ Manage, 2022 Mar 01;305:114426.
    PMID: 34998062 DOI: 10.1016/j.jenvman.2021.114426
    Poor performance of wet scrubbers in rubber processing plants due to breakthrough of specific volatile organic compounds (VOCs) causes odour impact events. The performance of wet scrubbers in the rubber drying process to remove VOCs was investigated in order to determine the responsible odorants. VOC emissions originating at the inlet and outlet of wet scrubbers were quantified using gas chromatography-mass spectrometry/olfactometry (GC-MS/O). Critical VOCs were identified alongside seasonal and daily variations of those VOCs. Altogether, 80 VOCs were detected in rubber emissions with 16 classified as critical VOCs based on their chemical concentration, high odour activity value (OAV) and unpleasant odour. Volatile fatty acids (VFAs) were the dominant VOCs with seasonal variations affecting emission composition. Results demonstrated the ineffectiveness of the wet scrubbers to mitigate odorous VOCs whereas the removal of some VOCs could be improved based on their polarity and solubility. It was found that there is a correlation between the wet scrubber performance and VFAs concentration in the emissions. The findings demonstrated that combining quantitative and sensory analyses improved accuracy in identifying odorous VOCs, which can cause odour annoyance from rubber processing. A VOC identification framework was proposed using both analyses approaches.
    Matched MeSH terms: Odors/analysis
  3. Toh C, Mohd-Hairul AR, Ain NM, Namasivayam P, Go R, Abdullah NAP, et al.
    BMC Res Notes, 2017 Nov 02;10(1):554.
    PMID: 29096695 DOI: 10.1186/s13104-017-2872-6
    BACKGROUND: Vanda Mimi Palmer (VMP) is commercially valuable for its strong fragrance but little is known regarding the fragrance production and emission sites on the flowers.

    RESULTS: Olfactory perception detected fragrance only from the petals and sepals. Light and Environmental Scanning Electron microscopy analyses on fresh tissues showed distributions of stomata and trichomes concentrated mostly around the edges. These results paralleled the rich starch deposits and intense neutral red stain, indicating strong fragrance and trichomes as potential main fragrance release sites. Next Generation Sequencing (NGS) transcriptomic data of adaxial and abaxial layers of the tissues showed monoterpene synthase transcripts specifically linalool and ocimene synthases distributed throughout the tissues. qPCR analyses taken at different time points revealed high levels of linalool and ocimene synthases transcripts in the early morning with maximal level at 4.00 am but remained low throughout daylight hours.

    CONCLUSIONS: Knowledge of the VMP floral anatomy and its fragrance production characteristics, which complemented our previous molecular and biochemical data on VMP, provided additional knowledge on how fragrance and flower morphology are closely intertwined. Further investigation on the mechanisms of fragrance biosynthesis and interaction of potential pollinators would elucidate the evolution of the flower morphology to maximize the reproduction success of this plant.

    Matched MeSH terms: Odors*
  4. Mohd Ali M, Hashim N, Abd Aziz S, Lasekan O
    Food Res Int, 2020 11;137:109675.
    PMID: 33233252 DOI: 10.1016/j.foodres.2020.109675
    Pineapple (Ananas comosus) is a tropical fruit that is highly relished for its unique aroma and sweet taste. It is renowned as a flavourful fruit since it contains a number of volatile compounds in small amounts and complex mixtures. Pineapple is also a rich source of minerals and vitamins that offer a number of health benefits. Ranked third behind banana and citrus, the demand for pineapple has greatly increased within the international market. The growth of the pineapple industry in the utilisation of pineapple food-based processing products as well as waste processing has progressed rapidly worldwide. This review discusses the nutritional values, physicochemical composition and volatile compounds, as well as health benefits of pineapples. Pineapple contains considerable amounts of bioactive compounds, dietary fiber, minerals, and nutrients. In addition, pineapple has been proven to have various health benefits including anti-inflammatory, antioxidant activity, monitoring nervous system function, and healing bowel movement. The potential of food products and waste processing of pineapples are also highlighted. The future perspectives and challenges with regard to the potential uses of pineapple are critically addressed. From the review, it is proven that pineapples have various health benefits and are a potential breakthrough in the agricultural and food industries.
    Matched MeSH terms: Odors/analysis
  5. Starkenmann C, Luca L, Niclass Y, Praz E, Roguet D
    J Agric Food Chem, 2006 Apr 19;54(8):3067-71.
    PMID: 16608232
    Polygonum odoratum Lour. has been reclassified as Persicaria odorata (Lour.) Soják [Wilson, K. L. Polygonum sensu lato (Polygonaceae) in Australia. Telopea 1988, 3, 177-182]; other synonyms currently used are Vietnamese mint or Vietnamese coriander and, in Malaysia, Daun Laksa or Laksa plant. The aerial parts of Laksa plant are highly aromatic, and they contain many organic compounds such as (Z)-3-hexenal, (Z)-3-hexenol, decanal, undecanal, and dodecanal that are typical for green, citrus, orange peel, and coriander odors. In addition to these aldehydes, 3-sulfanyl-hexanal and 3-sulfanyl-hexan-1-ol were discovered for the first time in this herb. The fresh leaves are pungent when they are chewed, although the active compound has never been identified. The pungency of Persicaria hydropiper (L.) Spach (formerly Polygonum hydropiper L., synonym water pepper) is produced by polygodial, a 1,4-dialdehyde derived from drimane terpenoids. We also identified polygodial as the active pungent compound in P. odorata (Lour.) Soják.
    Matched MeSH terms: Odors/analysis*
  6. Hackländer RPM, Janssen SMJ, Bermeitinger C
    Psychon Bull Rev, 2019 Apr;26(2):401-429.
    PMID: 30406397 DOI: 10.3758/s13423-018-1545-3
    Over the past nearly 35 years, there has been sporadic interest in what has commonly come to be known as the Proust phenomenon, whereby autobiographical memories are retrieved and experienced differently when evoked by odors as compared with other types of cues, such as words, images or sounds. The purpose of this review is threefold. First, we provide a detailed analysis of the methods used to investigate Proust effects. Second, we review and analyze the various findings from the literature and determine what we feel to be the most important and stable findings. Third, we provide a series of previously postulated and new hypotheses that attempt to account for the various findings. Given the early stage of research, the current review aims to provide a measure of organization to the field, as well serve as a guide for how future investigations may address the topic. We conclude with the recommendation that research in this area shift its focus from establishing the phenomenon towards explaining its causes.
    Matched MeSH terms: Odors*
  7. Yaacof N, Qamaruz Zaman N, Yusup Y, Yusoff S
    Environ Sci Pollut Res Int, 2019 Aug;26(23):24286-24299.
    PMID: 31214886 DOI: 10.1007/s11356-019-05517-z
    Malaysia is the second-largest producer and exporter of palm oil amounting to 39% of world palm oil production and 44% of world exports (MPOB, 2014). An enormous amount of palm oil mill effluent is released during palm oil milling, and the effluent causes a major odor problem. Many methods, such as biofiltering, can be adopted to manage the malodor. However, these methods are expensive and require high maintenance. The separation distance method can be used as an alternative due to its low cost and effectiveness. This research was conducted to verify the performance of three different methods, namely, in-field monitoring by using an olfactometer, CALPUFF model, and Gaussian plume model. Given that no research has compared the three methods, this study examined the effectiveness of the methods and determined which among them is suitable for use in Malaysia. The appropriate separation distances were 1.3 km for in-field monitoring, 1.2 km for the CALPUFF model, and 0.5 for the Gaussian plume model. These different values of separation distance were due to the various approaches involved in each method. This research determined an appropriate means to establish a proper separation distance for reducing odor nuisance in areas around palm oil mills.
    Matched MeSH terms: Odors/analysis*
  8. Andruszkiewicz PJ, D'Souza RN, Corno M, Kuhnert N
    Food Res Int, 2020 07;133:109164.
    PMID: 32466895 DOI: 10.1016/j.foodres.2020.109164
    Chemical transformations of Amadori compounds are responsible for the formation of aroma volatiles at the end of the Maillard reaction cascade, which in turn contributes to unique organoleptic characteristics of chocolate. A large amount of short peptides reported in fermented cocoa suggests the existence of a much larger variety of these flavor precursors than previously suspected. An HPLC-MS-MS study was performed on dried Malaysian cocoa beans to identify novel Amadori and Heyns compounds. In total, 34 species were found, including 26 previously unknown derived from di- and tripeptides. We illustrate how the structures were elucidated via tandem MS experiments, as well as present a comparative study on their relative quantities in samples coming from 11 countries of origin. There were significant differences between them, and discrimination was possible by principal component analysis based on Amadori content alone. However, the PCA separation could be a result of various post-harvest practices exerted among said countries.
    Matched MeSH terms: Odors
  9. Noor Hafizah, Y, Maskat, M. Y., Wan Aida, W. M., Maaruf, A. G.
    MyJurnal
    Storage study of mengkudu (Morinda citrifolia L.) extract was carried out to determine the effects
    of canning and storage period on pH, total polyphenol content, antioxidant activity, intensity of off-odour and aroma acceptance. Uncanned (control) and canned extract were stored for 0, 8, 16 and 24 weeks under room temperature. Results showed canning resulted in a significant (p
    Matched MeSH terms: Odors
  10. Yeap HY, Faruq G, Zakaria HP, Harikrishna JA
    ScientificWorldJournal, 2013;2013:569268.
    PMID: 24222741 DOI: 10.1155/2013/569268
    Allele Specific Amplification with four primers (External Antisense Primer, External Sense Primer, Internal Nonfragrant Sense Primer, and Internal Fragrant Antisense Primer) and sensory evaluation with leaves and grains were executed to identify aromatic rice genotypes and their F1 individuals derived from different crosses of 2 Malaysian varieties with 4 popular land races and 3 advance lines. Homozygous aromatic (fgr/fgr) F1 individuals demonstrated better aroma scores compared to both heterozygous nonaromatic (FGR/fgr) and homozygous nonaromatic (FGR/FGR) individuals, while, some F1 individuals expressed aroma in both leaf and grain aromatic tests without possessing the fgr allele. Genotypic analysis of F1 individuals for the fgr gene represented homozygous aromatic, heterozygous nonaromatic and homozygous nonaromatic genotypes in the ratio 20:19:3. Genotypic and phenotypic analysis revealed that aroma in F1 individuals was successfully inherited from the parents, but either molecular analysis or sensory evaluation alone could not determine aromatic condition completely. The integration of molecular analysis with sensory methods was observed as rapid and reliable for the screening of aromatic genotypes because molecular analysis could distinguish aromatic homozygous, nonaromatic homozygous and nonaromatic heterozygous individuals, whilst the sensory method facilitated the evaluation of aroma emitted from leaf and grain during flowering to maturity stages.
    Matched MeSH terms: Odors/analysis*
  11. Qamaruz-Zaman N, Milke MW
    Waste Manag, 2012 Dec;32(12):2426-30.
    PMID: 22819598 DOI: 10.1016/j.wasman.2012.06.023
    Research was conducted to determine suitable chemical parameters as indicators of odor from decomposing food wastes. Prepared food scraps were stored in 18 l plastic buckets (2 kg wet weight each) at 20 °C and 8 °C to reproduce high and low temperature conditions. After 1, 3, 7, 10 and 14 days of storage, the odor from the buckets were marked to an intensity scale of 0 (no odor) to 5 (intense) and the corresponding leachate analyzed for volatile fatty acids, ammonia and total organic carbon. A linear relationship between odor intensity and the measured parameter indicates a suitable odor indicator. Odor intensified with longer storage period and warmer surroundings. The study found ammonia and isovaleric acid to be promising odor indicators. For this food waste mixture, offensive odors were emitted if the ammonia and isovaleric acid contents exceeded 360 mg/l and 940 mg/l, respectively.
    Matched MeSH terms: Odors/analysis*
  12. Lasekan O, Abbas KA
    Crit Rev Food Sci Nutr, 2012;52(8):726-35.
    PMID: 22591343 DOI: 10.1080/10408398.2010.507910
    The characteristic flavor of exotic tropical fruits is one of their most attractive attributes to consumers. In this article, the enormous diversity of exotic fruit flavors is reviewed. Classifying some of the exotic fruits into two classes on the basis of whether esters or terpenes predominate in the aroma was also attempted. Indeed, as far as exotic tropical fruits are concerned, the majority of fruits have terpenes predominating in their aroma profile. Some of the fruits in this group are the Amazonian fruits such as pitanga, umbu-caja, camu-camu, garcinia, and bacuri. The ester group is made up of rambutan, durians, star fruit, snake fruit, acerola, tamarind, sapodilla, genipap, soursop, cashew, melon, jackfruit, and cupuacu respectively. Also, the role of sulphur-volatiles in some of the exotic fruits is detailed.
    Matched MeSH terms: Odors/analysis*
  13. Hidayat W, Shakaff AY, Ahmad MN, Adom AH
    Sensors (Basel), 2010;10(5):4675-85.
    PMID: 22399899 DOI: 10.3390/s100504675
    Presently, the quality assurance of agarwood oil is performed by sensory panels which has significant drawbacks in terms of objectivity and repeatability. In this paper, it is shown how an electronic nose (e-nose) may be successfully utilised for the classification of agarwood oil. Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA), were used to classify different types of oil. The HCA produced a dendrogram showing the separation of e-nose data into three different groups of oils. The PCA scatter plot revealed a distinct separation between the three groups. An Artificial Neural Network (ANN) was used for a better prediction of unknown samples.
    Matched MeSH terms: Odors/analysis
  14. Majid A, Burenhult N, Stensmyr M, de Valk J, Hansson BS
    Philos Trans R Soc Lond B Biol Sci, 2018 08 05;373(1752).
    PMID: 29915007 DOI: 10.1098/rstb.2017.0139
    Olfaction presents a particularly interesting arena to explore abstraction in language. Like other abstract domains, such as time, odours can be difficult to conceptualize. An odour cannot be seen or held, it can be difficult to locate in space, and for most people odours are difficult to verbalize. On the other hand, odours give rise to primary sensory experiences. Every time we inhale we are using olfaction to make sense of our environment. We present new experimental data from 30 Jahai hunter-gatherers from the Malay Peninsula and 30 matched Dutch participants from the Netherlands in an odour naming experiment. Participants smelled monomolecular odorants and named odours while reaction times, odour descriptors and facial expressions were measured. We show that while Dutch speakers relied on concrete descriptors, i.e. they referred to odour sources (e.g. smells like lemon), the Jahai used abstract vocabulary to name the same odours (e.g. musty). Despite this differential linguistic categorization, analysis of facial expressions showed that the two groups, nevertheless, had the same initial emotional reactions to odours. Critically, these cross-cultural data present a challenge for how to think about abstraction in language.This article is part of the theme issue 'Varieties of abstract concepts: development, use and representation in the brain'.
    Matched MeSH terms: Odors*
  15. Qamaruz-Zaman N, Abdul-Sukor NS, Ab-Rahman SA, Yaacof N
    Environ Sci Pollut Res Int, 2019 May;26(13):13658-13663.
    PMID: 30955198 DOI: 10.1007/s11356-019-04808-9
    Path analysis has been largely used in marketing research but has recently been applied in an environmental management context. This study evaluated the potential of path analysis in identifying the influence of moisture content on odor from decomposing food waste. Food waste with varying moisture content was monitored for odor concentration, microbial population density, oxygen uptake rate, volatile fatty acids, ammonia, and hydrogen sulfide. These various parameters were later analyzed using SmartPLS 3.0 software to produce the path analysis model using simultaneous equation modeling. Results indicate that odor concentration of food waste was not directly affected by moisture content (not significant, t-statistical 1.46  1.96) and subsequently odor. In order to manage food waste-related odors, it is recommended that the waste be kept at a moisture content lower than 40%. This is especially critical if prolonged storage is unavoidable.
    Matched MeSH terms: Odors/analysis*
  16. Omar MN, Nor NN, Idris NA
    Pak J Biol Sci, 2007 Apr 01;10(7):1044-9.
    PMID: 19070048
    Changes of aroma constituents of palm olein and selected oils after frying French fries have been studied. The aroma constituents of used oils were collected using a solid-phase microextraction (SPME) headspace technique with an absorbent of a divinylbenzene/carboxen (DVB/CAR) (50/30 microm) on polydimethylsiloxane (PDMS) fibre. The extracted volatiles were desorbed from the fibre in the injection port of the gas chromatograph at 250 degrees C and the aroma constituents were identified by GC-MS. Analytical data showed that volatile constituents of palm olein, soybean oil, corn oil and sunflower oil changed while frying continued from 2 to 40 h, respectively. In palm olein, the 2t,4t-decadienal content decreased from 14.7 to 5.5 microg g(-1) (40 h) whilst hexanal increased from 7.9 microg g(-1) (2 h) to 29.2 microg g(-1) (40 h), respectively. Similar result was also obtained from soybean oil after frying French fries. The 2t,4t-decadienal content decreased from 15.9 microg g(-1) (2 h) to 3.2 microg g(-1) after 40 h frying whilst hexanal increased from 10.2 microg g(-1) (2 h) to 34.2 microg g(-1) (40 h). Meanwhile, in corn oil, it was found that 2t,4t-decadienal decreased from 15.6 microg g(-1) (2 h) to 3.2 microg g(-1) (40 h) whilst hexanal increased from 11.3 microg g(-1) (2 h) to 33.8 microg g(-1) when frying time reached 40 h. In sunflower oil, it was found that 2t,4t-decadienal, decreased from 16.8 microg g(-1) (2 h) to 1.2 microg g(-1) (40 h) while hexanal increased from 9.5 microg g(-1) (2 h) to 32.4 microg g(-1) when frying time reached 40 h. It also showed that used oils exhibited off-odour characteristics due to the increasing amount ofhexanal while their freshness characteristics diminished due to the decreasing amount of 2t, 4t-decadienal.
    Matched MeSH terms: Odors/analysis
  17. Anuar NSS, Kassim AA, Utsumi M, Iwamoto K, Goto M, Shimizu K, et al.
    Microbes Environ, 2017 Dec 27;32(4):352-357.
    PMID: 29093279 DOI: 10.1264/jsme2.ME17109
    Geosmin and 2-methylisoborneol (MIB) outbreaks in tropical water bodies, such as Southeast Asia, by actinomycetes have not yet been elucidated in detail. Six Streptomyces isolates from lowland environments in Malaysia were selected and evaluated for their odor production under different temperatures. The gene responsible for the production of geosmin, geoA, was detected in all isolates, while only two isolates harbored tpc, which is responsible for 2-MIB production. This result suggested that geosmin and 2-MIB synthesis pathway genes already existed in the environment in the Tropics of Southeast Asia. Furthermore, our isolates produced musty odor compounds at 30°C, and differences were observed in musty odor production between various temperatures. This result indicated the potential for odor episodes in water bodies of the tropical countries of Southeast Asia throughout the year due to the mean annual ambient temperature of 27°C in the lowlands.
    Matched MeSH terms: Odors/analysis*
  18. Irwandi, J., Faridayanti, S., Mohamed, E.S.M., Hamzah, M.S., Torla, H.H., Che Man, Y.B.
    MyJurnal
    Gelatins from the skin of four local marine fish, namely “kerapu” (Epinephelus sexfasciatus), “jenahak” (Lutjianus argentimaculatus), “kembung” (Rastrelliger kanagurta), and “kerisi” (Pristipomodes typus) have been successfully extracted by acid extraction. Results characterization showed that the fish gelatins were comparable to the fish gelatins from other fish species previously reported. They appeared snowy white in color with crystal-like and light texture. The gelatine extracted from “kerapu” had the strongest fishy odor, followed by the gelatines derived from “jenahak”, “kembung” and “kerisi”. In terms of bloom strength, the gelatin extracted from “kerapu” was found to be the strongest one compared to others, with the bloom value of more than 2000 g. The gelatins developed in this study contained almost all essential amino acids, with glycine being the most predominant one.
    Matched MeSH terms: Odors
  19. Poh AH, Moghavvemi M, Leong CS, Lau YL, Safdari Ghandari A, Apau A, et al.
    PLoS One, 2017;12(2):e0171555.
    PMID: 28152031 DOI: 10.1371/journal.pone.0171555
    Classifying and quantifying mosquito activity includes a plethora of categories, ranging from measuring flight speeds, repellency, feeding rates, and specific behaviors such as home entry, swooping and resting, among others. Entomologists have been progressing more toward using machine vision for efficiency for this endeavor. Digital methods have been used to study the behavior of insects in labs, for instance via three-dimensional tracking with specialized cameras to observe the reaction of mosquitoes towards human odor, heat and CO2, although virtually none was reported for several important fields, such as repellency studies which have a significant need for a proper response quantification. However, tracking mosquitoes individually is a challenge and only limited number of specimens can be studied. Although tracking large numbers of individual insects is hailed as one of the characteristics of an ideal automated image-based tracking system especially in 3D, it also is a costly method, often requiring specialized hardware and limited access to the algorithms used for mapping the specimens. The method proposed contributes towards (a) unlimited open source use, (b) a low-cost setup, (c) complete guide for any entomologist to adapt in terms of hardware and software, (d) simple to use, and (e) a lightweight data output for collective behavior analysis of mosquitoes. The setup is demonstrated by testing a simple response of mosquitoes in the presence of human odor versus control, one session with continuous human presence as a stimuli and the other with periodic presence. A group of female Aedes aegypti (Linnaeus) mosquitoes are released into a white-background chamber with a transparent acrylic panel on one side. The video feed of the mosquitoes are processed using filtered contours in a threshold-adjustable video. The mosquitoes in the chamber are mapped on the raster where the coordinates of each mosquito are recorded with the corresponding timestamp. The average distance of the blobs within the frames against time forms a spectra where behavioral patterns can be observed directly, whether any collective effect is observed. With this method, 3D tracking will not be required and a more straightforward data output can be obtained.
    Matched MeSH terms: Odors
  20. Chow XH, Ting CM, Wan Hamizan AK, Zahedi FD, Tan HJ, Remli R, et al.
    J Laryngol Otol, 2024 Mar;138(3):301-309.
    PMID: 37259908 DOI: 10.1017/S0022215123000919
    OBJECTIVE: The aim of this study was to identify the potential electrophysiological biomarkers of human responses by comparing the electroencephalogram brain wave changes towards lavender versus normal saline in a healthy human population.

    METHOD: This study included a total of 44 participants without subjective olfactory disturbances. Lavender and normal saline were used as the olfactory stimulant and control. Electroencephalogram was recorded and power spectra were analysed by the spectral analysis for each alpha, beta, delta, theta and gamma bandwidth frequency upon exposure to lavender and normal saline independently.

    RESULTS: The oscillatory brain activities in response to the olfactory stimulant indicated that the lavender smell decreased the beta activity in the left frontal (F7 electrode) and central region (C3 electrode) with a reduction in the gamma activity in the right parietal region (P4 electrode) (p < 0.05).

    CONCLUSION: Olfactory stimulants result in changes of electrical brain activities in different brain regions, as evidenced by the topographical brain map and spectra analysis of each brain wave.

    Matched MeSH terms: Odors
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