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“Comparison of spectroscopic techniques combined with chemometrics for cocaine powder analysis”. Eliaerts J, Meert N, Dardenne P, Baeten V, Pierna J-AF, Van Durme F, De Wael K, Samyn N, Journal Of Analytical Toxicology 44, 851 (2020). http://doi.org/10.1093/JAT/BKAA101
Abstract: Spectroscopic techniques combined with chemometrics are a promising tool for analysis of seized drug powders. In this study, the performance of three spectroscopic techniques [Mid-InfraRed (MIR), Raman and Near-InfraRed (NIR)] was compared. In total, 364 seized powders were analyzed and consisted of 276 cocaine powders (with concentrations ranging from 4 to 99 w%) and 88 powders without cocaine. A classification model (using Support Vector Machines [SVM] discriminant analysis) and a quantification model (using SVM regression) were constructed with each spectral dataset in order to discriminate cocaine powders from other powders and quantify cocaine in powders classified as cocaine positive. The performances of the models were compared with gas chromatography coupled with mass spectrometry (GC-MS) and gas chromatography with flame-ionization detection (GC-FID). Different evaluation criteria were used: number of false negatives (FNs), number of false positives (FPs), accuracy, root mean square error of cross-validation (RMSECV) and determination coefficients (R-2). Ten colored powders were excluded from the classification data set due to fluorescence background observed in Raman spectra. For the classification, the best accuracy (99.7%) was obtained with MIR spectra. With Raman and NIR spectra, the accuracy was 99.5% and 98.9%, respectively. For the quantification, the best results were obtained with NIR spectra. The cocaine content was determined with a RMSECV of 3.79% and a R-2 of 0.97. The performance of MIR and Raman to predict cocaine concentrations was lower than NIR, with RMSECV of 6.76% and 6.79%, respectively and both with a R-2 of 0.90. The three spectroscopic techniques can be applied for both classification and quantification of cocaine, but some differences in performance were detected. The best classification was obtained with MIR spectra. For quantification, however, the RMSECV of MIR and Raman was twice as high in comparison with NIR. Spectroscopic techniques combined with chemometrics can reduce the workload for confirmation analysis (e.g., chromatography based) and therefore save time and resources.
Keywords: A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 2.5
DOI: 10.1093/JAT/BKAA101
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“Geranium lake pigments : the role of the synthesis on the structure and composition”. Beltran V, Marchetti A, De Meyer S, Nuyts G, De Wael K, Dyes And Pigments 189, 109260 (2021). http://doi.org/10.1016/J.DYEPIG.2021.109260
Abstract: Eosin Y has an extraordinary capacity to form complexes with metallic elements, that have applications in many different fields, from photovoltaics and photocatalysis to historical artists? pigments. To unravel the complexes reactivity, it is essential to have a precise knowledge of their structure and composition, as well as how these can be affected by the synthesis protocol, an often underestimated factor. This manuscript presents a thorough investigation of the structure and composition of eosin Y complexes based on Al and Pb, by FTIR, XRPD and Raman spectroscopy, with a particular focus on the effect of the synthesis conditions. Results clearly show the change of the coordination mode in Pb complexes depending on the protocol, while the structure of Al complexes remains stable. In both cases, the formation of by-products was observed. Additionally, a detailed band assignment of the FTIR and Raman spectra of eosin Y and Pb and Al complexes is described, providing interesting details such as the interaction between the metallic ion and the xanthene moiety (chromophore). This is extremely important for the analysis of historical paintings where eosin Y is bonded to metallic ions, as well as for other materials in dye-sensitized solar cells, wastewater treatment or photocatalysis.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 3.473
DOI: 10.1016/J.DYEPIG.2021.109260
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“Elemental constituents of atmospheric aerosols in Recife, North-East Brazil”. Van Grieken R, Van 't dack L, Costa Dantas C, Moura de Amorim W, Maenhaut W, Environmental pollution: series B : chemical and physical 4, 143 (1982). http://doi.org/10.1016/0143-148X(82)90025-8
Abstract: Few data are available on the inorganic atmospheric pollution in the rapidly expanding cities of South America, like Recife, on the Atlantic Coast of North-east Brazil. Therefore, the elemental composition of atmospheric aerosols was investigated for nine sites in the Recife conurbation and a fairly remote site in the area. Total aerosol samples were collected on cellulose filters for analysis by energy dispersive X-ray fluorescence and cascade impactors were used to collect the aerosols as a function of particle size for subsequent analysis by proton-induced X-ray emission. Local soil aliquots were also analysed. About eighteen elements were quantified in all cases. The average total atmospheric concentrations appeared to be well above natural levels but usually lower than, or comparable with, those of North American and European cities. Dispersal of sea spray and of local soil (often contaminated with, for example, Cu, Zn and Pb from industrial sources) contributes predominantly to the total atmospheric load in Recife. However, the particle size fraction results also indicated strong excesses in the small particle mode for S, K, V, Mn, Ni, Cu, Zn, Br and Pb, mainly in the downtown area. Again, the corresponding enrichment factors were only moderate in comparison with other published urban data.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0143-148X(82)90025-8
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“Effects of alkaline aluminate waste dumping on seawater chemistry”. Vandelannoote R, Van 't dack L, Van Grieken R, Marine environmental research 21, 275 (1987). http://doi.org/10.1016/0141-1136(87)90050-X
Abstract: The alkaline aluminate waste, of which 10002000 tonnes are dumped a few times a year off the Belgian coast in the Southern Bight of the North Sea, contains 5·4% NaCl, 1·8% dissolved Al and 7·4% NaOH, in addition to traces of heavy metals and some aniline- and phenol-derivatives. The pH rises locally to 8-5 and the total Al-concentration reaches 120niglitre−1(corresponding to an initial waste dilution factor of only 150) in the 10-m wide track just beyond the discharging barge, but these decay quickly to pH 8·1 and 1 mg litre-1 in the 30-m wide track, 500m behind the barge. The relation between the waste concentration and seawater pH was studied. The white precipitate that forms immediately in the sea was identified as Mg6Al2CO3(OH)164H20 (hydrotalcite-manasseite like). No trace of it was found in the local sediments.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0141-1136(87)90050-X
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“Characterization and optimization of \beta-galactosidase immobilization process on a mixed-matrix membrane”. Jochems P, Satyawali Y, van Roy S, Doyen W, Diels L, Dejonghe W, Enzyme and microbial technology 49, 580 (2011). http://doi.org/10.1016/J.ENZMICTEC.2011.06.010
Abstract: β-Galactosidase is an important enzyme catalyzing not only the hydrolysis of lactose to the monosaccharides glucose and galactose but also the transgalactosylation reaction to produce galacto-oligosaccharides (GOS). In this study, β-galactosidase was immobilized by adsorption on a mixed-matrix membrane containing zirconium dioxide. The maximum β-galactosidase adsorbed on these membranes was 1.6 g/m2, however, maximal activity was achieved at an enzyme concentration of around 0.5 g/m2. The tests conducted to investigate the optimal immobilization parameters suggested that higher immobilization can be achieved under extreme parameters (pH and temperature) but the activity was not retained at such extreme operational parameters. The investigations on immobilized enzymes indicated that no real shift occurred in its optimal temperature after immobilization though the activity in case of immobilized enzyme was better retained at lower temperature (5 °C). A shift of 0.5 unit was observed in optimal pH after immobilization (pH 6.5 to 7). Perhaps the most striking results are the kinetic parameters of the immobilized enzyme; while the Michaelis constant (Km) value increased almost eight times compared to the free enzyme, the maximum enzyme velocity (Vmax) remained almost constant.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.ENZMICTEC.2011.06.010
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“Geometry errors in 14 MeV neutron activation analysis”. Van Grieken R, Speecke A, Hoste J, Journal of radioanalytical chemistry 13, 225 (1973). http://doi.org/10.1007/BF02514126
Abstract: The effects of inaccurate sample sizes and sample positioning on 14 MeV neutron activation analysis results are estimated for 30, 20 and 10 mm diameter targets. It appears that axial positioning is the most critical parameter and that using a larger tritium target will yield an overall improvement of the reproducibility.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02514126
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“The half-life of 28Al”. Van Schandevijl R, Van Grieken R, Hoste J, Journal of radioanalytical chemistry 9, 55 (1971). http://doi.org/10.1007/BF02514012
Abstract: The half-life of28Al was redetermined on aluminium samples of different origin. Three different counting techniques were applied. The availability of highly purified samples (up to 99.9999%), the use of very fast electronic counting equipment and a complete automatisation allowed a good precision to be obtained in the final result of 2.2405 min.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02514012
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“Simultaneous determination of silicon and phosphorus in cast iron by 14 MeV neutron activation analysis”. Van Grieken R, Speecke A, Hoste J, Journal of radioanalytical chemistry 6, 385 (1970). http://doi.org/10.1007/BF02513966
Abstract: A fast (10 min), non-destructive simultaneous determination of silicon and phosphorus in cast iron and steel by 14 MeV neutron activation was developed. The 1.78 MeV28Al activity (T=2.24 min) induced by the reaction28Si(n, p)28Al is counted on a NaI(Tl) detector. Two measurements are made to correct for the 1.81 MeV56Mn activity (T=2.58 hr) from the iron matrix. However,28Al is also produced via31P(n, α)28Al. By (n, 2n) reaction, phosphorus yields also30P (T=2.6 min), the 0.511 MeV annihilation radiation of which is counted by two opposite NaI(Tl) detectors in coincidence. Again, two successive coincidence measurements are carried out in order to take into account the53Fe activity (β+; T=8.9 min) from54Fe(n, 2n)53Fe. The28Al measurement is appropriately corrected via the computed phosphorus content. An oxygen flux monitor was used to normalize to the same flux. Nuclear interferences have been examined. Special attention has been paid to the presence of copper. The standard deviation for phosphorus being as high as ca. 0.09% P for a single determination, this technique can only be practical as an independent phosphorus analysis for high phosphorus cast irons. The precision on the28Al measurement is 5% relative for 0.2% Si and 2.5% above 1% Si.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02513966
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“Spatial neutron flux distributions around A 14 MeV neutron generator”. Van Grieken R, Speecke A, Hoste J, Journal of radioanalytical chemistry 10, 95 (1972). http://doi.org/10.1007/BF02518771
Abstract: The neutron flux distribution in the vicinity of 30, 20 and 10 mm diameter targets is measured by irradiating concentric ring-type iron monitors at different distances from the target and counting the induced56Mn activity. Considering the many uncertainties, satisfactory agreement was found between theory and experiment.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02518771
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“Relative evaluation of neutron activation, X-ray fluorescence and spark source mass spectrometry for multi-element analysis of geothermal waters”. Blommaert W, Vandelannoote R, Van 't dack L, Gijbels R, van Grieken R, Journal of radioanalytical chemistry 57, 382 (1980)
Keywords: A3 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Graphene textures: tubules and whiskers related to fullerene crystallography”. Van Tendeloo G, Amelinckx S, van Landuyt J, Acta crystallographica: section A: foundations of crystallography 49, 355 (1993)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.307
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“Superlattice variants in Sr2CuO2(CO3): an electron microscopy study”. Milat O, Van Tendeloo G, van Landuyt J, Amelinckx S, Acta crystallographica: section A: foundations of crystallography 49, 357 (1993)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.307
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“Occupational allergic contact dermatitis from bisphenol A in vinyl gloves”. Matthieu L, Godoi AFL, Lambert J, Van Grieken R, Contact dermatitis 49, 281 (2003). http://doi.org/10.1111/J.0105-1873.2003.0241.X
Abstract: Allergic contact dermatitis caused by polyvinyl chloride gloves is rarely reported, and in only 2 cases was bisphenol A considered to be the responsible sensitizer. We report a patient with occupational hand dermatitis after the use of a new type of high-density vinyl (HDV) gloves. Patch tests showed positive (++) reactions to both used and new HDV gloves and to bisphenol A. Chemical analysis by gas chromatography-mass spectrometry demonstrated the presence of bisphenol A in the HDV gloves. Replacement by nitrile rubber gloves resulted in complete clearance of the hand dermatitis.
Keywords: A1 Journal article; Translational Pathophysiological Research (TPR); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1111/J.0105-1873.2003.0241.X
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“Classical model of clusters of screened charges in quantum dots”. Cândido L, Rino J-P, Studart N, Peeters FM, Brazilian journal of physics 27, 312 (1997)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.732
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“Correlation effects of DX centers on electron mobility in delta doped semiconductors investigated by Monte Carlo simulations”. Shi JM, Farias GA, Koenraad PM, van de Stadt AFW, Peeters FM, Wolter JH, Devreese JT, Brazilian journal of physics 27, 327 (1997)
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 0.732
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“Electrons in non-homogeneous magnetic fields”. Peeters FM, Matulis A, Brazilian journal of physics 24, 283 (1994)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.81
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“Low dimensional semiconductor structures”. Peeters FM, Hipólito O, Brazilian journal of physics 22, 183 (1992)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.81
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“Polaron effects on cyclotron mass due to interface and slab phonons in GaAs/AlGaAs quantum wells”. Hai G-Q, Studart N, Peeters FM, Brazilian journal of physics 26, 219 (1996)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.81
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“Analise de solos por meio de fluorescencia de raios-X nao-dispersiva”. Costa Dantas C, Da Silveira Dantas H, Van 't dack L, Van Grieken R, Química nova 4, 110 (1981)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Physico-chemical fate of chromium compounds in the lung sheep model”. Perrault G, Dufresne A, Strati G, McNeil M, Michaud D, Baril M, Bégin R, Labbé, J, Larivière P, Eeckhaoudt S, Van Grieken R, Journal of toxicology and environmental health 44, 247 (1995). http://doi.org/10.1080/15287399509531958
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/15287399509531958
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“Behavior of semi-volatile particles under a laser and electron beam: influence on the quality of analytical results”. Worobiec A, Potgieter-Vermaak S, Darchuk L, Vishnyakov V, Potgieter H, Van Grieken R, AIP conference proceedings 1267, 523 (2010). http://doi.org/10.1063/1.3482653
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1063/1.3482653
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“Composition of aerosols from the shelter of the Chernobyl power plant”. Darchuk L, Worobiec A, Khan V, Krasnov V, Van Grieken R, AIP conference proceedings 1267, 512 (2010). http://doi.org/10.1063/1.3482646
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1063/1.3482646
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“Associations between PM2.5 and heart rate variability are modified by particle composition and beta-blocker use in patients with coronary heart disease”. de Hartog JJ, Lanki T, Timonen KL, Hoek G, Janssen NAH, Ibald-Mulli A, Peters A, Heinrich J, Tarkainen TH, Van Grieken R, van Wijnen JH, Brunekreef B, Pekkanen J, Environmental health perspectives 117, 105 (2009). http://doi.org/10.1289/EHP.11062
Abstract: Background: It has been hypothesized that ambient particulate air pollution is able to modify the autonomic nervous control of the heart, measured as heart rate variability (HRV) . Previously we reported heterogeneous associations between particulate matter with aerodynamic diameter < 2.5 µm (PM2.5) and HRV across three study centers. Objective: We evaluated whether exposure misclassification, effect modification by medication, or differences in particle composition could explain the inconsistencies. Methods: Subjects with coronary heart disease visited clinics biweekly in Amsterdam, the Netherlands ; Erfurt, Germany ; and Helsinki, Finland for 68 months. The standard deviation (SD) of NN intervals on an electrocardiogram (ECG ; SDNN) and high frequency (HF) power of HRV was measured with ambulatory ECG during paced breathing. Outdoor levels of PM2.5 were measured at a central site. In Amsterdam and Helsinki, indoor and personal PM2.5 were measured during the 24 hr preceding the clinic visit. PM2.5 was apportioned between sources using principal component analyses. We analyzed associations of indoor/personal PM2.5, elements of PM2.5, and source-specific PM2.5 with HRV using linear regression. Results: Indoor and personal PM2.5 were not associated with HRV. Increased outdoor PM2.5 was associated with decreased SDNN and HF at lags of 2 and 3 days only among persons not using beta-blocker medication. Traffic-related PM2.5 was associated with decreased SDNN, and long-range transported PM2.5 with decreased SDNN and HF, most strongly among persons not using beta blockers. Indicators for PM2.5 from traffic and long-range transport were also associated with decreased HRV. Conclusions: Our results suggest that differences in the composition of particles, beta-blocker use, and obesity of study subjects may explain some inconsistencies among previous studies on HRV.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1289/EHP.11062
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“Increased accuracy in the automated interpretation of large epma data sets by the use of an expert system”. Janssens K, Vanborm W, van Espen P, Journal of research of the National Bureau of Standards (1934) 93, 260 (1988). http://doi.org/10.6028/JRES.093.037
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.6028/JRES.093.037
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“Chronic interstitial nephritis in agricultural communities is a toxin induced proximal tubular nephropathy”. Vervaet BA, Nast CC, Jayasumana C, Schreurs G, Roels F, Herath C, Kojc N, Samaee V, Rodrigo S, Gowrishankar S, Mousson C, Dassanayake R, Orantes CM, Vuiblet V, Rigothier C, d' Haese PC, de Broe ME, Kidney international 97, 350 (2019). http://doi.org/10.1016/J.KINT.2019.11.009
Abstract: Almost 30 years after the detection of chronic interstitial nephritis in agricultural communities (CINAC) its etiology remains unknown. To help define this we examined 34 renal biopsies from Sri Lanka, El Salvador, India and France of patients with chronic kidney disease 2-3 and diagnosed with CINAC by light and electron microscopy. In addition to known histopathology, we identified a unique constellation of proximal tubular cell findings including large dysmorphic lysosomes with a light-medium electron-dense matrix containing dispersed dark electron-dense non-membrane bound “aggregates”. These aggregates associated with varying degrees of cellular/tubular atrophy, apparent cell fragment shedding and no-weak proximal tubular cell proliferative capacity. Identical lysosomal lesions, identifiable by electron microscopy, were observed in 9% of renal transplant implantation biopsies, but were more prevalent in six month (50%) and 12 month (67%) protocol biopsies and in indication biopsies (76%) of calcineurin inhibitor treated transplant patients. The phenotype was also found associated with nephrotoxic drugs (lomustine, clomiphene, lithium, cocaine) and in some patients with light chain tubulopathy, all conditions that can be directly or indirectly linked to calcineurin pathway inhibition or modulation. One hundred biopsies of normal kidneys, drug/toxin induced nephropathies, and overt proteinuric patients of different etiologies to some extent could demonstrate the light microscopic proximal tubular cell changes, but rarely the electron microscopic lysosomal features. Rats treated with the calcineurin inhibitor cyclosporine for four weeks developed similar proximal tubular cell lysosomal alterations, which were absent in a dehydration group. Overall, the finding of an identical proximal tubular cell (lysosomal) lesion in CINAC and calcineurin inhibitor nephrotoxicity in different geographic regions suggests a common paradigm where CINAC patients undergo a tubulotoxic mechanism similar to calcineurin inhibitor nephrotoxicity.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory Experimental Medicine and Pediatrics (LEMP); Pathophysiology
Impact Factor: 8.395
DOI: 10.1016/J.KINT.2019.11.009
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“Biogeochemical study of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean) in June 2004”. Harlay J, Borges AV, van der Zee C, Delille B, Godoi RHM, Schiettecatte L-S, Roevros N, Aerts K, Lapernat P-E, Rebreanu L, Groom S, Daro M-H, Van Grieken R, Chou L, Progress in oceanography 86, 317 (2010). http://doi.org/10.1016/J.POCEAN.2010.04.029
Abstract: The present paper synthesizes data obtained during a multidisciplinary cruise carried out in June 2004 at the continental margin of the northern Bay of Biscay. The data-set allows to describe the different stages of a coccolithophore bloom dominated by Emiliania huxleyi. The cruise was carried out after the main spring phytoplankton bloom that started in mid-April and peaked in mid-May. Consequently, low phosphate (PO4 < 0.2 μM) and silicate (DSi < 2.0 μM) concentrations, low partial pressure of carbon dioxide (pCO2) and high calcite saturation degree in surface waters combined with thermal stratification, probably favoured the blooming of coccolithophores. During the period of the year our cruise was carried out, internal tides induce enhanced vertical mixing at the continental shelf break leading to the injection of inorganic nutrients to surface waters that probably trigger the bloom. The bloom developed as the water-column stratified and as the water mass was advected over the continental shelf, following the general residual circulation in the area. The most developed phase of the bloom was sampled in a remote sensed high reflectance (HR) patch over the continental shelf that was characterized by low chlorophyll-a (Chl-a) concentration in surface waters (<1.0 μg L−1), high particulate inorganic carbon (PIC) concentration (not, vert, similar8 μmol L−1) and coccolithophore abundance up to 57 × 106 cells L−1. Transparent exopolymer particles (TEP) concentrations ranged between 15 and 75 μg C L−1 and carbon content of TEP represented up to 26% of the particulate organic carbon (POC; maximum concentration of 15.5 μmol L−1 in the upper 40 m). Integrated primary production (PP) ranged between 210 and 680 mg C m−2 d−1 and integrated calcification (CAL) ranged between 14 and 140 mg C m−2 d−1, within the range of PP and CAL values previously reported during coccolithophore blooms in open and shelf waters of the North Atlantic Ocean. Bacterial protein production (BPP) measurements in surface waters (0.30.7 μg C L−1 h−1) were much higher than those reported during early phases of coccolithophore blooms in natural conditions, but similar to those during peak and declining coocolithophorid blooms reported in mesocosms. Total alkalinity anomalies with respect to conservative mixing (ΔTA) down to −49 μmol kg−1 are consistent with the occurrence of biogenic precipitation of calcite, while pCO2 remained 15107 μatm lower than atmospheric equilibrium (372 μatm). The correlation between ΔTA and pCO2 suggested that pCO2 increased in part due to calcification, but this increase was insufficient to overcome the background under-saturation of CO2. This is related to the biogeochemical history of the water masses due to net carbon fixation by the successive phytoplankton blooms in the area prior to the cruise, hence, the investigated area remained a sink for atmospheric CO2 despite calcification.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.POCEAN.2010.04.029
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“‘biogeom&rsquo, : an R package for simulating and fitting natural shapes”. Shi P, Gielis J, Quinn BK, Niklas KJ, Ratkowsky DA, Schrader J, Ruan H, Wang L, Niinemets Ü, Niinennets U, Annals of the New York Academy of Sciences 1516, 123 (2022). http://doi.org/10.1111/NYAS.14862
Abstract: Many natural objects exhibit radial or axial symmetry in a single plane. However, a universal tool for simulating and fitting the shapes of such objects is lacking. Herein, we present an R package called 'biogeom' that simulates and fits many shapes found in nature. The package incorporates novel universal parametric equations that generate the profiles of bird eggs, flowers, linear and lanceolate leaves, seeds, starfish, and tree-rings, and three growth-rate equations that generate the profiles of ovate leaves and the ontogenetic growth curves of animals and plants. 'biogeom' includes several empirical datasets comprising the boundary coordinates of bird eggs, fruits, lanceolate and ovate leaves, tree rings, seeds, and sea stars. The package can also be applied to other kinds of natural shapes similar to those in the datasets. In addition, the package includes sigmoid curves derived from the three growth-rate equations, which can be used to model animal and plant growth trajectories and predict the times associated with maximum growth rate. 'biogeom' can quantify the intra- or interspecific similarity of natural outlines, and it provides quantitative information of shape and ontogenetic modification of shape with important ecological and evolutionary implications for the growth and form of the living world.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Impact Factor: 5.2
DOI: 10.1111/NYAS.14862
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“Comparison of a universal (but complex) model for avian egg shape with a simpler model”. Shi P, Gielis J, Niklas KJ, Annals of the New York Academy of Sciences 1514, 34 (2022). http://doi.org/10.1111/NYAS.14799
Abstract: Recently, a universal equation by Narushin, Romanov, and Griffin (hereafter, the NRGE) was proposed to describe the shape of avian eggs. While NRGE can simulate the shape of spherical, ellipsoidal, ovoidal, and pyriform eggs, its predictions were not tested against actual data. Here, we tested the validity of the NRGE by fitting actual data of egg shapes and compared this with the predictions of our simpler model for egg shape (hereafter, the SGE). The eggs of nine bird species were sampled for this purpose. NRGE was found to fit the empirical data of egg shape well, but it did not define the egg length axis (i.e., the rotational symmetric axis), which significantly affected the prediction accuracy. The egg length axis under the NRGE is defined as the maximum distance between two points on the scanned perimeter of the egg's shape. In contrast, the SGE fitted the empirical data better, and had a smaller root-mean-square error than the NRGE for each of the nine eggs. Based on its mathematical simplicity and goodness-of-fit, the SGE appears to be a reliable and useful model for describing egg shape.
Keywords: Editorial; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Impact Factor: 5.2
DOI: 10.1111/NYAS.14799
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“A simple way to calculate the volume and surface area of avian eggs”. Shi P, Chen L, Quinn BK, Yu K, Miao Q, Guo X, Lian M, Gielis J, Niklas KJ, Annals of the New York Academy of Sciences 1524, 118 (2023). http://doi.org/10.1111/NYAS.15000
Abstract: Egg geometry can be described using Preston's equation, which has seldom been used to calculate egg volume (V) and surface area (S) to explore S versus V scaling relationships. Herein, we provide an explicit re-expression of Preston's equation (designated as EPE) to calculate V and S, assuming that an egg is a solid of revolution. The side (longitudinal) profiles of 2221 eggs of six avian species were digitized, and the EPE was used to describe each egg profile. The volumes of 486 eggs from two avian species predicted by the EPE were compared with those obtained using water displacement in graduated cylinders. There was no significant difference in V using the two methods, which verified the utility of the EPE and the hypothesis that eggs are solids of revolution. The data also indicated that V is proportional to the product of egg length (L) and maximum width (W) squared. A 2/3-power scaling relationship between S and V for each species was observed, that is, S is proportional to (LW2)(2/3). These results can be extended to describe the shapes of the eggs of other species to study the evolution of avian (and perhaps reptilian) eggs.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Impact Factor: 5.2
DOI: 10.1111/NYAS.15000
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“Dispersal of suspended matter in Makasar Strait and the Flores Basin”. Eisma D, Kalf J, Karmini M, Mook WG, Van Put A, Bernard P, Van Grieken R, Netherlands journal of sea research 24, 383 (1989). http://doi.org/10.1016/0077-7579(89)90116-6
Abstract: In November 1984 in Makasar and the Flores Basin water samples were collected (T, S, dissolved O2, total CO2), bottom samples (sediment composition) and suspended matter (particle composition, particle size). A sediment trap was moored in the Flores Basin at 4600 m depth for nearly four months, covering the dry season. In the Flores Basin there are indications for bottom flow resuspending bottom material or preventing suspended material from settling; in Makasar Strait there is probably inflow of deep water both from the south and from the north, resulting in a very slow bottom water flor. Bottom deposits in Makasar Strait and the Flores Basin are predominantly terrigenous, with an admixture of organic carbonate and silica (mostly coccoliths). Volcanic material is primarily present near to the volcanoes in the south and reaches the deeper basins by slumping. In the suspended matter no volcanic particles and little planktonic material were found, although the latter form 10 to 15% of the top sediment and of the material deposited in the sediment trap. In suspension particles with a large concentration of tin (Sn) were found associated mainly with iron. They probably come from northern Kalimantan or northern Sulawesi. Suspended matter concentrations were mainly less than 0.5 mg·dm−3, only off the Mahakam river mouth were concentrations higher than 1 mg·dm−3. Particle size was erratic because of the variable composition of the coarser particles in suspension. Organic matter concentrations in suspension (in mg·dm−3) roughly follow the distribution of total suspended matter but organic content (in %) of the suspended matter does not show any trends. All organic matter in suspension is of marine origin except in the Mahakam river and estuary. Deposition rates, as estimated from the sediment trap results, are 150 mg·cm−2·a−1 for the total sediment, 26 mg·cm−2·a−1 for carbonate and 13 mg·cm−2·a−1 for organic matter. Flocs and fibres in suspension were only found in and below the Mahakam river plume that reaches ca 400 km from the river mouth to the southeast, and in surface waters associated with plankton (diatoms). The formation of these flocs (broken-up macroflocs or marine snow) is primarily related to particle concentration, turbulence, and the presence of organisms that produce sticky material or glue particles together.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0077-7579(89)90116-6
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