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Incidence of ambergris washed ashore
Ambergris is a valuable substance obtained
from Sperm whale. It is either found floating in the sea
or obtained by cutting open theanimal. It is produced
in the intestine and retained mostly in the colon.
Ambergris is a solid inflamable waxy substance
Structure-Activity Relationships in Odor Perception of Drimane Derivatives
The woody, ambergris-Iike odor of trans-decalone derivatives of type 5 increases with the introduction of equatorial alkyl substituents in the C(9)-positionand decreases drastically in the corresponding 9-epi derivatives. Complete stereocontrol of odor perception has been observed for the diastereoisomers of y-bicyclohomofarnesal 1 and 2. A similar tendency in odor perception has been recognized in substituted alcohols of type 12. The sandalwood- like ambergris note found in Polywood\u27": (14) disappeared in corresponding alkyl substituted acetates. The molecular basis of the \u27steroid-type\u27 scent of some esters of type 39 was hitherto unknown
Relation Structure moléculaire - Odeur Utilisation des Réseaux de Neurones pour l’estimation de l’Odeur Balsamique
Les molécules odorantes (parfums ou flaveurs) sont utilisées dans une grande variété de produits de consommation, pour inciter les consommateurs à associer les impressions favorables à un produit donné. La Relation Structure moléculaire-Odeur (SOR) est cruciale pour la synthèse de ces molécules mais est très difficile à établir due à la subjectivité de l’odeur. Ce travail présente une approche de prédiction de l'odeur des molécules basée sur les descripteurs moléculaires. Les techniques d’analyse en composantes principales (PCA) et de d’analyse de colinéarité permettent d’identifier les descripteurs les plus pertinents. un réseau de neurones supervisé5 à deux couches (cachée et sortie) est employé pour corréler la structure moléculaire à l’odeur. La base de données décrite précédemment est utilisée pour l’apprentissage. Un ensemble de paramètres est modifié jusqu’à la satisfaction de la meilleure régression.
Les résultats obtenus sont encouragent, ainsi les descripteurs moléculaires convenables corrèlent efficacement l'odeur des molécules. C’est la première étape d’un modèle générique en développement pour corréler l'odeur avec les structures moléculaire
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A 1200-year record of parrotfish teeth suggests centuries of overfishing in Belize.
Humans have utilized the Mesoamerican Reef for millennia but the effects of prehistorical and historical fishing on this ecosystem remain understudied. To assess long-term trends in reef fish abundance in the central Belizean portion, we used three reef matrix cores from this region to construct a record of parrotfish (Labridae) tooth abundance relative to the total number of all fish tooth subfossils. Parrotfish positively affect reef accretion rates and play a pivotal role in maintaining reefs in a coral-dominated state. Our study examined a 1200-year record across three coral cays: Elbow and Lagoon Cays and Bakers Rendezvous. Despite initial increases of fish tooth abundance at all three cays, declines were observed well before modern reef degradation. At Elbow Cay, an initial decline, likely due to Pre-Columbian Maya fishing, appears to be halted near the time of Spanish arrival. A subsequent decline begins at Elbow and Lagoon Cays likely due to Spanish colonization. The religious practices of the Catholic Spanish and the arrival of English privateers and logwooders likely increased fishing pressure. Bakers Rendezvous shows rapid accretion and parrotfish tooth accumulation as well as high tooth abundances, even as the other two cays show declines. Its sharper, more recent decline is likely the result of either the use of new, more southern fishing territories for Catholic Maya converts, the 1832 founding of Stann Creek Town by the Catholic Garifuna, or an interaction of the two. Our data suggest that the origins of reef degradation began hundreds of years before modern declines
On a sperm whale landed at Kalpeni island with notes on ambergris
In the Indian Ocean The sperm whale Physeter macrocephalus is found concentrated more in the Arabian Sea upto 20° N and between 50° and 80° E especially in the Gulf of Aden and approaches a little east of Minicoy Island and off Sri Lanka. The morphology of the sperm whales
landed at various islands in the Lakshadweep are Total length 530; Distance from eye to snout 115 cm; Height of the body 98cm and Girth of the body 62cm. Ambergris is a valuable substance obtained from the sperm whale. In 1974 ambergris weighing 90 kg was found floating in the sea and it was auctioned at the rate of Rs. 1,160 per kg. Of this amount, 55% was paid to the fisherman who recovered it and 45% was credited to the Fisheries Department
On the role of chirality in structure-odor relationships
The influence of chirality on odors was studied on 16 enantiomeric pairs according to the dispersion/hydrogen bonding theory of receptor-odorant interaction. Comparisons of molecular structures were made by superimposition of optimized conformations, using the Alchemy II package. The quality of fit was assessed using the RMS parameter included in Alchemy II and a new index for hydrogen bonding: the angle between H-bonds in the two molecules. In the case of camphoraceous odorants where an interaction model was already known superimposition according to the model led to correct predictions of the high similarity of odors observed in enantiomeric pairs. For several urinous odorants comparisons were made using d-androstenone as a reference compound for the urinous odor. Correct predictions were obtained for l-androstenone, both enantiomers of androsta-4, 16-dienone, and (+)-2-methyl-4-(5,5,6-exo-trimethy1-2-exonorbornyl)-cyclobexane. The (−) enantiomer of the latter compound was correctly predicted only if it was assumed that its weak intensity is due to a partial interaction with the hydrophobic zone of the receptor. For ambergris odorants which have a complex odor (−)-Ambrox was selected as the reference compound. The odors of (+)-Ambrox and enantiomers of four other compounds (ambergris or woody) were correctly predicted by superimposition. For nootkatone and three derivatives which have a grapefruit note for one enantiomer and a woody note for the other no models or reference compounds were available. The superimpositions were made between grapefruit enantiomers, on the one hand, and woody enantiomers on the other hand. Woody and grapefruit characters were correctly predicted in all cases. The limits of this approach based on molecular modelling are discusse
Isotopic Analysis of Human Migration Among the Ancient Maya of Ambergris Caye, Belize
This thesis uses the isotopic composition of tooth enamel from two Maya sites on Ambergris Caye Belize, to identify basic patterns of population movement among the Classic period Maya. Three individuals from San Juan and ten individuals from Chac Balam will shed light on the origin of individuals buried at the sites, including those with nonlocal grave goods. Strontium and oxygen isotope values provide new information on Maya coastal populations and suggest that at least one individual with a distinct body position had a nonlocal origin. Carbon isotope values reveal a childhood diet related to, but not the same as, the proteins adults consumed.
Fewer nonlocal individuals were identified at Ambergris than other Maya studies, which may result from the size of the sample or that people moved from places with similar isotope values. Two individuals buried with foreign grave goods have isotope values that are consistent with the Caribbean Coast and the Caye. This suggest that ideas were moving rather than people and provides a direction for future research in the region
Female Barrenness, Bodily Access and Aromatic Treatments in Seventeenth-Century England
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, CC BY-NC-ND 3.0 which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made, see https://creativecommons.org/licenses/by-nc-nd/3.0/.Scholars examining medical practice in early modern England have often remarked upon the complexities of the relationship between male physicians and female patients. It has been noted that ideas of female modesty and concern about the potential erotic nature of contact between patients and practitioners could affect the treatment of certain disorders. This paper contributes to this on-going discussion by examining the use of pungent substances to diagnose and treat female barrenness. Diagnostic tests included in medical treatises could rely upon the woman’s ability to perceive a particular substance. These tests thus put women at the centre of the diagnosis of their disorders and allowed them to negotiate access to their reproductive bodies. Similarly medical practitioners included a range of treatments for infertility that involved the fumes of certain substances entering the womb or surrounding the body. These treatments may have allowed women, and perhaps their medical practitioners, to choose a method of remedy that did not involve the application of external lotions to the genitalia. Thus by considering the multi-sensory nature of medical treatment this paper will highlight that the diversity of remedies advocated in early modern medical texts would perhaps have allowed women to restrict access to their reproductive bodies, while still obtaining diagnosis and treatment.Peer reviewe
Ambrein: a minor, but common constituent of mammalian faeces?
For nearly 200 years, the only natural source of the alcohol ambrein has been coproliths produced in about 1% of sperm whales and in related jetsam. However, the finding of ambrein in adipocere/faeces of human corpses, led us to hypothesise that ambrein might occur in the faeces of other mammals. Herein, we used a recently developed gas chromatography-mass spectrometry method, with suitable derivatisation of the hindered hydroxy group of ambrein, to screen a number of extracts of mammalian faeces. Minor proportions of ambrein were detected in digested human sewage sludge and in the dung of elephant, domestic cattle, giraffe and buffalo. Whether ambrein formation in the terrestrial species is associated with coprolith formation, is unknown, but solid deposits known as enteroliths and fecaliths occur in humans and some domestic animals
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