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1.
Archaeometry ; 63(1): 142-155, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33510540

ABSTRACT

The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican-era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb-poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce, the Romans brought together the efficient, millennium-old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks.

2.
Placenta ; 31(7): 615-20, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20452670

ABSTRACT

Superficial invasion of extravillous trophoblasts (EVTs) and impaired spiral artery remodelling are characterizing phenomena in pregnancies complicated by pre-eclampsia (PE) and fetal growth restriction (FGR). However, the underlying causes remain unclear. In this study, gene expression in decidua basalis tissue from pregnancies complicated with PE and/or FGR (n = 18) and normal pregnancies (n = 17) was assessed by Affymetrix HG Focus microarray to obtain hints of mechanisms involved in the pathogenesis. A total of 200 differentially expressed transcripts were detected at a false discovery rate (FDR)

Subject(s)
Fetal Growth Retardation/enzymology , Matrix Metalloproteinase 1/metabolism , Pre-Eclampsia/enzymology , Trophoblasts/metabolism , Decidua/metabolism , Female , Gene Expression , Gene Expression Profiling , Humans , Pregnancy
3.
Nature ; 440(7081): 199-202, 2006 Mar 09.
Article in English | MEDLINE | ID: mdl-16525470

ABSTRACT

The Earth's mantle is isotopically heterogeneous on length scales ranging from centimetres to more than 10(4) kilometres. This heterogeneity originates from partial melt extraction and plate tectonic recycling, whereas stirring during mantle convection tends to reduce it. Here we show that mid-ocean ridge basalts from 2,000 km along the southeast Indian ridge (SEIR) display a bimodal hafnium isotopic distribution. This bimodality reveals the presence of ancient compositional striations (streaks) in the Indian Ocean upper mantle. The number density of the streaks is described by a Poisson distribution, with an average thickness of approximately 40 km. Such a distribution is anticipated for a well-stirred upper mantle, in which heterogeneity is continually introduced by plate tectonic recycling, and redistributed by viscous stretching and convective refolding.

4.
Science ; 310(5756): 1947-50, 2005 Dec 23.
Article in English | MEDLINE | ID: mdl-16293721

ABSTRACT

The long-favored paradigm for the development of continental crust is one of progressive growth beginning at approximately 4 billion years ago (Ga). To test this hypothesis, we measured initial 176Hf/177Hf values of 4.01- to 4.37-Ga detrital zircons from Jack Hills, Western Australia. epsilonHf (deviations of 176Hf/177Hf from bulk Earth in parts per 10(4)) values show large positive and negative deviations from those of the bulk Earth. Negative values indicate the development of a Lu/Hf reservoir that is consistent with the formation of continental crust (Lu/Hf approximately 0.01), perhaps as early as 4.5 Ga. Positive epsilon(Hf) deviations require early and likely widespread depletion of the upper mantle. These results support the view that continental crust had formed by 4.4 to 4.5 Ga and was rapidly recycled into the mantle.

5.
Neuromuscul Disord ; 14(1): 46-50, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14659412

ABSTRACT

We report a novel heteroplasmic T-->C mutation at nt position 582 within the mitochondrial tRNA(Phe) gene of a 70-year-old woman with mitochondrial myopathy. No other family members were affected, suggesting that our patient was a sporadic case. The muscle showed frequent ragged red fibers and 43% cytochrome c oxidase deficient fibers. The mutation alters a conserved base pairing in the aminoacyl acceptor stem. The mutation load was 70% in muscle homogenate and varied from 0 to 95% in individual muscle fiber segments. Cytochrome c oxidase-negative fibers showed significantly higher levels of mutated mtDNA (>75%) than Cytochrome c oxidase-positive fibers (<55%). This mutation adds to the previously described four pathogenic mutations in the tRNA(Phe) gene.


Subject(s)
DNA, Mitochondrial/genetics , Mitochondria/genetics , Mitochondrial Myopathies/genetics , Muscle, Skeletal/metabolism , Point Mutation/genetics , RNA, Transfer, Phe/genetics , Aged , Amino Acid Substitution/genetics , Amino Acyl-tRNA Synthetases/genetics , Cell Respiration/genetics , DNA Mutational Analysis , Electron Transport Complex IV/metabolism , Female , Humans , Mitochondria/metabolism , Mitochondrial Myopathies/diagnosis , Mitochondrial Myopathies/pathology , Muscle, Skeletal/pathology , Sequence Homology, Nucleic Acid
6.
Nature ; 418(6901): 949-52, 2002 Aug 29.
Article in English | MEDLINE | ID: mdl-12198540

ABSTRACT

Determining the chronology for the assembly of planetary bodies in the early Solar System is essential for a complete understanding of star- and planet-formation processes. Various radionuclide chronometers (applied to meteorites) have been used to determine that basaltic lava flows on the surface of the asteroid Vesta formed within 3 million years (3 Myr) of the origin of the Solar System. Such rapid formation is broadly consistent with astronomical observations of young stellar objects, which suggest that formation of planetary systems occurs within a few million years after star formation. Some hafnium-tungsten isotope data, however, require that Vesta formed later (approximately 16 Myr after the formation of the Solar System) and that the formation of the terrestrial planets took a much longer time (62(-14)(+4504) Myr). Here we report measurements of tungsten isotope compositions and hafnium-tungsten ratios of several meteorites. Our measurements indicate that, contrary to previous results, the bulk of metal-silicate separation in the Solar System was completed within <30 Myr. These results are completely consistent with other evidence for rapid planetary formation, and are also in agreement with dynamic accretion models that predict a relatively short time (approximately 10 Myr) for the main growth stage of terrestrial planet formation.

7.
Toxicol Sci ; 65(1): 126-34, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11752692

ABSTRACT

Methylene blue trihydrate is used widely as a dye and therapeutic agent. Methylene blue was administered by gavage to 30 animals/sex/dose group in a 0.5% aqueous methylcellulose suspension at doses of 0, 25, 50, 100, and 200 mg/kg. Blood samples from 10 animals/sex/dose group were collected at the end of study weeks 1, 6, and 13. Methylene blue treatment resulted in methemoglobin formation and oxidative damage to red blood cells, leading to a regenerative anemia and a variety of tissue and biochemical changes secondary to erythrocyte injury. An early change was a dose-related increase in methemoglobin, where the response of rats and mice was similar in magnitude. Mice appeared to be more sensitive than rats to the formation of Heinz bodies and the development of anemia that was characterized by a decrease in hemoglobin, hematocrit, and erythrocyte count. Splenomegaly was apparent in all treated mice and in the 100 mg/kg (males only) and 200 mg/kg rats at necropsy. There was a dose-related increase in absolute and relative spleen weight for both species. Microscopic examination revealed increased splenic hematopoiesis in all mice treatment groups and in rats at the 50 mg/kg dose level and above. Splenic congestion and bone marrow hyperplasia were also observed in these rat-dose groups. Mice at the higher doses showed hematopoiesis in the liver and accumulation of hemosiderin in Kupffer cells. These gross and microscopic findings are consistent with the development of hemolytic anemia. A dose-related increase in the reticulocyte count during study weeks 6 and 13 suggested a compensatory response to anemia.


Subject(s)
Methemoglobin/drug effects , Methylene Blue/toxicity , Anemia/chemically induced , Animals , Blood Cell Count , Body Weight/drug effects , Bone Marrow/drug effects , Bone Marrow/pathology , Dose-Response Relationship, Drug , Female , Heinz Bodies/drug effects , Hematocrit , Hemosiderin/drug effects , Hemosiderin/metabolism , Kupffer Cells/drug effects , Kupffer Cells/metabolism , Liver/drug effects , Liver/pathology , Male , Methemoglobin/metabolism , Methylene Blue/administration & dosage , Mice , Mice, Inbred Strains , Rats , Rats, Inbred F344 , Sex Factors , Spleen/drug effects , Spleen/pathology , Splenomegaly/chemically induced , Toxicity Tests
8.
Ugeskr Laeger ; 163(34): 4593-4, 2001 Aug 20.
Article in Danish | MEDLINE | ID: mdl-11530569

ABSTRACT

Moderate hyperhomocysteinaemia is associated with hypothyroidism. Increased levels of homocysteine might contribute to a greater cardiovascular risk. This paper reports a case of transient myxoedema, owing to postpartum thyroiditis. The fluctuation of P-homocysteine was inversely correlated to the free thyroxine index. We recommend TSH screening of patients with unexplained hyperhomocysteinaemia.


Subject(s)
Hyperhomocysteinemia/etiology , Hypothyroidism/complications , Myxedema/complications , Puerperal Disorders/complications , Thyroiditis, Autoimmune/complications , Abortion, Induced , Adult , Diagnosis, Differential , Female , Humans , Hyperhomocysteinemia/blood , Hypothyroidism/blood , Hypothyroidism/etiology , Myxedema/blood , Myxedema/etiology , Pregnancy , Puerperal Disorders/blood , Thyroiditis, Autoimmune/blood , Thyroiditis, Autoimmune/etiology , Thyrotropin/blood
9.
Eur J Nucl Med ; 28(7): 831-5, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11504079

ABSTRACT

Both subjects with a low likelihood for coronary artery disease (CAD) and patients with normal findings on coronary angiography have been used as reference populations in non-invasive stress testing, including myocardial perfusion scintigraphy. Both of these criteria of normality--low likelihood of CAD and normal coronary angiography--have been criticised, and consensus on this issue is lacking. The aim of this study was to compare two different reference populations by testing the performance of artificial neural networks designed to interpret myocardial scintigrams. The networks were trained on myocardial perfusion scintigrams from 87 patients with angiographically documented CAD and on studies from one of two different reference groups: 48 patients with no signs of CAD based on angiography or 128 healthy volunteers with a likelihood for CAD <5%. The performance of the two different networks was then tested using scintigrams from a separate test group of 68 patients. Coronary angiography was used as the gold standard in this group. The network trained on patients with no signs of CAD based on angiography showed an area under the receiver operating characteristic (ROC) curve of 93%. The ROC area for the network trained on healthy volunteers was 72%, and this difference was statistically significant (P=0.03). The results of this study using artificial neural networks suggest that normal angiography should be preferred as the reference standard in myocardial scintigraphy when a patient is examined for CAD prior to possible angiography. Whether the same is true for other indications, e.g. in prognostic evaluation, is unknown.


Subject(s)
Coronary Angiography , Coronary Circulation , Coronary Disease/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Adult , Aged , Area Under Curve , Coronary Stenosis/diagnostic imaging , Coronary Vessels/diagnostic imaging , Female , Humans , Male , Middle Aged , Neural Networks, Computer , ROC Curve , Radiopharmaceuticals , Reference Values , Risk Factors , Technetium Tc 99m Sestamibi
10.
Nature ; 408(6813): 701-4, 2000 Dec 07.
Article in English | MEDLINE | ID: mdl-11130068

ABSTRACT

Up to 10 per cent of the ocean floor consists of plateaux--regions of unusually thick oceanic crust thought to be formed by the heads of mantle plumes. Given the ubiquitous presence of recycled oceanic crust in the mantle source of hotspot basalts, it follows that plateau material should also be an important mantle constituent. Here we show that the geochemistry of the Pleistocene basalts from Logudoro, Sardinia, is compatible with the remelting of ancient ocean plateau material that has been recycled into the mantle. The Sr, Nd and Hf isotope compositions of these basalts do not show the signature of pelagic sediments. The basalts' low CaO/Al2O3 and Ce/Pb ratios, their unradiogenic 206Pb and 208Pb, and their Sr, Ba, Eu and Pb excesses indicate that their mantle source contains ancient gabbros formed initially by plagioclase accumulation, typical of plateau material. Also, the high Th/U ratios of the mantle source resemble those of plume magmas. Geochemically, the Logudoro basalts resemble those from Pitcairn Island, which contain the controversial EM-1 component that has been interpreted as arising from a mantle source sprinkled with remains of pelagic sediments. We argue, instead, that the EM-1 source from these two localities is essentially free of sedimentary material, the geochemical characteristics of these lavas being better explained by the presence of recycled oceanic plateaux. The storage of plume heads in the deep mantle through time offers a convenient explanation for the persistence of chemical and mineralogical layering in the mantle.

11.
Ugeskr Laeger ; 162(43): 5778-81, 2000 Oct 23.
Article in Danish | MEDLINE | ID: mdl-11082678

ABSTRACT

INTRODUCTION: This investigation is the Danish contribution to a Nordic comparative study of other drugs than alcohol found in road users. MATERIAL AND METHODS: 255 blood samples received from the police for alcohol and/or drug determination during one week in 1996 were investigated for drugs. RESULTS: 56 (22%) of the 255 blood samples were positive for other drugs than alcohol. Cannabis was detected in 11%, benzodiazepines, mainly diazepam and flunitrazepam, in 9% and amphetamine in 5% of the blood samples. DISCUSSION: The police suspected other drugs than alcohol in 3% of the 255 blood samples, but drugs were detected in 22%. This investigation showed that the frequency of other drugs than alcohol was similar in Denmark and Norway for the blood samples with an alcohol concentration above the statutory limit. This contrasts with the fact that the number of blood samples from road users investigated for substances other than alcohol is about 200/year in Denmark and 4000/year in Norway.


Subject(s)
Accidents, Traffic , Central Nervous System Stimulants/blood , Narcotics/blood , Pharmaceutical Preparations/blood , Substance-Related Disorders/blood , Adult , Aged , Blood Specimen Collection , Central Nervous System Stimulants/adverse effects , Denmark , Drug-Related Side Effects and Adverse Reactions , Forensic Medicine , Humans , Middle Aged , Narcotics/adverse effects , Substance-Related Disorders/complications
12.
Ugeskr Laeger ; 162(39): 5205-8, 2000 Sep 25.
Article in Danish | MEDLINE | ID: mdl-11043046

ABSTRACT

INTRODUCTION: The purpose of this study was to investigate fatal poisonings among drug addicts in 1997 and to compare the results to similar investigations from 1985 and 1991. MATERIAL AND METHODS: All fatal intoxications among drug addicts in Denmark in 1997, investigated at the three Institutes of Forensic Medicine in Denmark. RESULTS: The number of fatal intoxications increased by 32% from 1991 to 1997, mainly outside the metropolitan area, The average age increased from 32 to 36 years. The proportion of heroin/morphine intoxications increased from 57% to 71%. The most commonly used drugs were as in 1991 heroin/morphine, diazepam and methadone. The frequency of cocaine increased from one positive case in 1991 to 14% positive cases in 1997. DISCUSSION: This study showed an increasing number of fatal intoxications and changes in drug abuse pattern and place of death since 1991.


Subject(s)
Opioid-Related Disorders/mortality , Substance-Related Disorders/mortality , Adolescent , Adult , Analgesics, Opioid/poisoning , Cause of Death , Denmark/epidemiology , Drug Overdose , Female , Forensic Medicine/statistics & numerical data , Heroin/poisoning , Humans , Male , Methadone/poisoning , Middle Aged , Morphine/poisoning , Opioid-Related Disorders/complications , Substance-Related Disorders/complications
13.
J Heart Lung Transplant ; 19(9): 873-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11008077

ABSTRACT

BACKGROUND: Several studies have explored the feasibility of using myocardial perfusion imaging to detect allograft vasculopathy after heart transplantation. We undertook the present prospective consecutive study to comparatively evaluate the role of serial myocardial perfusion single-photon emission computed tomography (SPECT) scanning and coronary arteriography (CAG) in detecting coronary artery stenosis suitable for coronary angioplasty in heart transplant recipients. METHODS: Within a 2-week interval during a follow-up period of 5.6 (95% confidence limits 2.1 to 12) years, 255 serial CAGs and myocardial perfusion scintigraphies were performed in 67 patients. Arteriography and scintigraphy were performed once yearly after heart transplantation. We retrospectively analyzed the data. RESULTS: Myocardial scintigraphy showed pathologic reversible defects in 9 out of 67 patients. Four of these patients had significant (>50% and also >70%) focal segmental stenosis in the middle and proximal parts of the coronary arteries (Type A lesions), 1 had diffuse and circumferential narrowing in the distal parts (Type B lesions), whereas CAG showed no lesions in the remaining 4 patients. The patients with significant Type A lesions were revascularized with percutaneous coronary angioplasty. Coronary arteriography showed that 1 patient had extensive Type A and Type B lesions, whereas myocardial perfusion scans detected no. The predictive value of a negative (normal) SPECT was 98% (95% confidence limits 94% to 100%) for the detection of lesions suited for revascularization. CONCLUSIONS: Annual myocardial SPECT seems well suited to screen for significant coronary artery stenosis. A SPECT study without reversible defects virtually excludes lesions suitable for coronary artery revascularization.


Subject(s)
Coronary Disease/diagnostic imaging , Heart Transplantation , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Adolescent , Adult , Child , Coronary Angiography , Female , Humans , Male , Middle Aged , Organophosphorus Compounds , Organotechnetium Compounds , Prospective Studies , Radiopharmaceuticals , Sensitivity and Specificity , Technetium Tc 99m Sestamibi
14.
Clin Physiol ; 20(4): 253-61, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10886256

ABSTRACT

Artificial neural networks are systems of elementary computing units capable of learning from examples. They have been applied to automated interpretation of myocardial perfusion images and have been shown to perform even better than experienced physicians. It has been shown that physicians interpreting myocardial perfusion images benefit from the advice of such networks. These networks have been developed and validated in the same hospital. However, widespread use of neural networks will only take place if the networks can maintain a high accuracy in other hospitals, i.e. hospitals using different gamma cameras, different acquisition techniques, different study protocols, etc. The purpose of this study was to develop a neural network in one hospital and test it in another. An artificial neural network was trained to detect coronary artery disease using myocardial perfusion scintigrams from 135 patients at a Swedish hospital. Thereafter, this network was tested using scintigrams from 68 patients at a Danish hospital and compared to six criteria based on expert physician analysis and quantitative analysis by the CEqual program. The sensitivity of the network was significantly higher than that of one of the physician criteria (0. 92 versus 0.71) and two of the CEqual-based criteria (0.94 versus 0. 63 and 0.96 versus 0.65) compared at equal specificities. It was concluded that an artificial neural network can maintain high accuracy in a hospital other than the one where it was developed.


Subject(s)
Coronary Disease/diagnostic imaging , Diagnosis, Computer-Assisted , Image Processing, Computer-Assisted/methods , Neural Networks, Computer , Heart/diagnostic imaging , Hospital Information Systems , Humans , Radionuclide Angiography , Reproducibility of Results , Sensitivity and Specificity
15.
Nature ; 404(6777): 488-90, 2000 Mar 30.
Article in English | MEDLINE | ID: mdl-10761914

ABSTRACT

Modern basalts have seemingly lost all 'memory' of the primitive Earth's mantle except for an ambiguous isotopic signal observed in some rare gases. Although the Earth is expected to have reached a thermal steady state within several hundred million years of accretion, it is not known how and when the initial chemical fractionations left over from planetary accretion (and perhaps a stage involving a magma ocean) were overshadowed by fractionations imposed by modern-style geodynamics. Because of the lack of samples older than 4 Gyr, this early dynamic regime of the Earth is poorly understood. Here we compare published Hf-Nd isotope data on supracrustals from Isua, Greenland, with similar data on lunar rocks and the SNC (martian) meteorites, and show that, about 3.8 Gyr ago, the geochemical signature of the Archaean mantle was partly inherited from the initial differentiation of the Earth. The observed features seem to indicate that the planet at that time was still losing a substantial amount of primordial heat. The survival of remnants from an early layering in the modern deep mantle may account for some unexplained seismological, thermal and geochemical characteristics of the Earth as observed today.

16.
Science ; 285(5429): 879-82, 1999 Aug 06.
Article in English | MEDLINE | ID: mdl-10436154

ABSTRACT

Lead, oxygen, and osmium isotopic ratios measured on Hawaiian basalts can be matched with the isotopic ratios inferred for recycled ancient oceanic crust. High-precision hafnium isotopic data for lavas from several Hawaiian volcanoes identify old pelagic sediments in their source. These observations support the recycling hypothesis, whereby the mantle source of ocean island basalts includes ancient subducted oceanic crust. Hyperbolic lead-hafnium isotopic relations among Hawaiian basalts further indicate that upper mantle material is not involved in the production of hot spot basalts.

17.
Toxicol Sci ; 48(1): 14-20, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10330679

ABSTRACT

Pentachlorophenol (PCP) has been used as an herbicide, algaecide, defoliant, wood preservative, germicide, fungicide, and molluscicide. A 28-day toxicity study of PCP in F344/N rats of both sexes was conducted to select dose levels for a carcinogenicity study. Groups of 10 male and 10 female rats were given 0, 200, 400, 800, 1600, or 3200 ppm PCP in feed for 28 days. The incidences of minimal to mild hepatocyte degeneration in males and females exposed to 400 ppm or greater and the incidences of centrilobular hepatocyte hypertrophy in the 3200-ppm groups were increased. For carcinogenicity studies, groups of 50 male and 50 female F344/N rats were fed diets containing 200, 400, or 600 PCP for 2 years. A stop-exposure group of 60 male and 60 female rats received 1000 ppm of PCP in feed for 52 weeks and control feed thereafter for the remainder of the 2-year studies; 10 male and 10 female rats were evaluated at 7 months. Survival of 600-ppm males was significantly greater than that of the controls; survival of all other exposed groups was similar to that of the control groups. Mean body weights of the 400- and 600-ppm groups were generally less than those of the controls throughout the studies. There was no evidence of carcinogenic activity of PCP in male or female rats fed diets containing 200, 400, or 600 ppm for 2 years. Stop-exposure study males and females regained a transitory body weight reduction by the end of the 2 year study, and males had better survival than the controls. At a 7-month interim evaluation, the incidences of centrilobular hypertrophy in stop-exposure males and females exceeded those in the controls. At 2 years, malignant mesothelioma originating from the tunica vaginalis was present in 9 1000-ppm males and 1 control male (p = 0.014). Nasal squamous cell carcinomas were present in five 1000-ppm males and 1 control male. This incidence was not significantly increased but exceeded the historical control range (0-4%). Based on the increased incidences of mesotheliomas and nasal tumors, there was some evidence of carcinogenic activity of PCP in male rats given a diet containing 1000 ppm for 1 year followed by control diet for 1 year. There was no evidence of PCP carcinogenic activity in stop-exposure female rats.


Subject(s)
Environmental Pollutants/toxicity , Pentachlorophenol/toxicity , Animals , Body Weight/drug effects , Carcinogenicity Tests , Drug Administration Schedule , Environmental Pollutants/administration & dosage , Female , Hypertrophy/pathology , Liver/drug effects , Liver/pathology , Male , Mesothelioma/chemically induced , Mesothelioma/pathology , Nose Neoplasms/chemically induced , Nose Neoplasms/pathology , Pentachlorophenol/administration & dosage , Rats , Rats, Inbred F344 , Survival Rate , Testicular Neoplasms/chemically induced , Testicular Neoplasms/pathology , Testis/pathology
18.
Science ; 283(5406): 1303-1306, 1999 Feb 26.
Article in English | MEDLINE | ID: mdl-10037596

ABSTRACT

Six garnet pyroxenites from Beni Bousera, Morocco, yield a mean lutetium-hafnium age of 25 +/- 1 million years ago and show a wide range in hafnium isotope compositions (varepsilonHf = -9 to +42 25 million years ago), which exceeds that of known basalts (0 to +25). Therefore, primary melts of garnet pyroxenites cannot be the source of basalts. The upper mantle may be an aggregate of pyroxenites that were left by the melting of oceanic crust at subduction zones and peridotites that were contaminated by the percolation of melts from these pyroxenites. As a consequence, the concept of geochemical heterogeneities as passive tracers is inadequate. Measured lutetium-hafnium partitioning of natural minerals requires a reassessment of some experimental work relevant to mantle melting in the presence of garnet.

19.
Ugeskr Laeger ; 161(48): 6622-5, 1999 Nov 29.
Article in Danish | MEDLINE | ID: mdl-10643346

ABSTRACT

In the period 1992-1996, both years included, 1079 cases of deaths from poisoning by drugs or poisons were found by forensic-chemical analyses at The Institute of Forensic Medicine, Dept. of Forensic Chemistry, in Copenhagen, covering a population of 2.4 million. Morphine was by far the most frequently occurring compound accounting for 421 deaths, followed by methadone with 185 deaths. Then alcohol, ketobemidone, and carbon monoxide were represented with 80, 74 and 66 deaths, respectively. Drug addicts dominated in the survey with 549 cases. According to Danish law, autopsy with following chemical analyses must be performed on all dead drug addicts, whereas many other deaths by poisoning are defined only from the medicine found in the vicinity of the dead body.


Subject(s)
Opioid-Related Disorders/mortality , Poisoning/mortality , Substance-Related Disorders/mortality , Adolescent , Adult , Aged , Denmark/epidemiology , Drug Overdose , Female , Forensic Medicine/statistics & numerical data , Humans , Male , Middle Aged , Suicide/statistics & numerical data
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