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Papers by Martin Bucknall

Experimental Eye Research, Feb 1, 2019

The research complied with the tenets of the declaration of Helsinki. Informed consent was obtain... more The research complied with the tenets of the declaration of Helsinki. Informed consent was obtained from all participants who provided tear samples.

Food Research International, Apr 1, 2018

Headspace gas chromatography mass spectrometry (HS-GC-MS) was used to measure changes in selected... more Headspace gas chromatography mass spectrometry (HS-GC-MS) was used to measure changes in selected volatile flavour compounds in fresh banana during low temperature heat pump drying. Ten compounds from a range of chemical classes were measured during drying at three different drying conditions. Ester compounds were found to be the most affected, with losses varying from 25 to 87% during drying. Three patterns of depletion were observed in this study. Ester and aldehyde levels reduced quickly during the early stages of drying, but levels stabilised at non-zero values towards the end of drying; alcohol levels initially increased, then decreased and stabilised; whilst high molecular weight compounds, such as elemicine and eugenol, were not affected significantly. Selective diffusion and volatility affected the degree of flavour retention.

ChemInform, Feb 16, 2015

An Easy One-Pot Synthesis of Diverse 2,5-Di(2-pyridyl)pyrroles: A Versatile Entry Point to Metal ... more An Easy One-Pot Synthesis of Diverse 2,5-Di(2-pyridyl)pyrroles: A Versatile Entry Point to Metal Complexes of Functionalized, Meridial and Tridentate 2,5-Di(2-pyridyl)pyrrolato Ligands.-Although only moderate yields are obtained an easy one-pot route to 2,5-dipyridylpyrrole ligands (IV) is described. Incorporation of the ligands into Pd-and Ru-complexes is investigated as well as the electrochemical properties of these complexes.-(MCSKIMMING, A.; DIACHENKO, V.;

Journal of Functional Foods, Jun 1, 2018

This study investigated the bioactivity interactions in vitro and ex vivo, and cellular uptake in... more This study investigated the bioactivity interactions in vitro and ex vivo, and cellular uptake interaction between βcarotene and some common anthocyanins. The combined antioxidant and anti-inflammatory activities of βcarotene and different anthocyanins were assessed in both chemical and biological systems. Bioactivity synergy was seen in none of the combinations in no system studied. Some mixtures even showed antagonistic effects. All of the tested anthocyanins except for delphinidin-3-glucoside, tested at 7.5 μM, significantly improved the cellular uptake of β-carotene (2.5 μM) by 68-200% although such increases of β-carotene intracellular content did not lead to an enhancement of the combined bioactivities. The increase of β-carotene absorption to a particular concentration facilitated the pro-oxidant activity of β-carotene. This effect could be partly responsible for the bioactivity antagonism seen in some of the combinations.

Science, Jun 19, 2020

Perovskite decomposition in detail Solar cells are subject to heating when operating in sunlight,... more Perovskite decomposition in detail Solar cells are subject to heating when operating in sunlight, and the organic components of hybrid perovskite solar cells, especially the commonly used methylammonium cation, can undergo thermal decomposition. Encapsulation can limit decomposition by bringing such reactions to equilibrium and can prevent exposure to damaging ambient moisture. Shi et al. examined several encapsulation schemes for perovskite films and devices by probing volatile products with gas chromatography–mass spectrometry (see the Perspective by Juarez-Perez and Haro). Pressure-tight polymer/glass stack encapsulation was effective in suppressing gas transfer and allowed solar cells containing methylammonium to pass harsh moisture and thermal cycling tests. Science , this issue p. eaba2412 ; see also p. 1309

Investigative Ophthalmology & Visual Science, Jun 23, 2017

European Chemical Bulletin, Nov 9, 2012

Low temperature molten salts based on ionic liquids have received considerable attention over the... more Low temperature molten salts based on ionic liquids have received considerable attention over the last 3 decades as potential alternative solvents for aluminium reduction. Recent reports in the literature have identified 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl) amide ([C 3 mpip][NTf 2 ]) as a promising candidate for low temperature aluminium reduction processes. The formation of aluminium metal deposition was confirmed in these studies by both visual inspection and SEM-EDX analysis in the selected mixtures with AlCl 3 , but little is known about the anodic processes occurring in the cell. This work presents the results of a preliminary electrochemical study of the anodic and cathodic reactions occurring in the ionic liquid mixtures 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)amide ([C 3 mpip][NTf 2 ]) with AlCl 3 at different temperatures, concentrations and electrode materials. Analysis of voltammetric responses of [C 3 mpip][NTf 2 ]-[AlCl 3 ] x for x=0.3 indicated that the anodic process is limited by mass transport for this particular electrolyte composition. In addition, the formation of Cl 2 was confirmed to take place at a dimensionally stable anode. Aluminium deposition experiments gave inconsistent results however and gas analysis indicated that the [C 3 mpip][NTf 2 ]-[AlCl 3 ] x mixture at a prolonged elevated temperature at least partially decomposes into fluoro-carbons and chloro-compounds.

Chemical Communications, 2017

A new ruthenium(ii) complex capable of catalysing both CO2 reduction and water oxidation was desi... more A new ruthenium(ii) complex capable of catalysing both CO2 reduction and water oxidation was designed and synthesised. The electro-catalytic efficiency and robustness of the complex together with the electronic effect of its co-ligands were investigated to develop next generation dual activity electrocatalysts.

Journal of Inherited Metabolic Disease, Sep 1, 2002

Systemic carnitine deficiency (CDSP) (McKusick 212140) is a rare autosomal recessive disease caus... more Systemic carnitine deficiency (CDSP) (McKusick 212140) is a rare autosomal recessive disease caused by defective plasma membrane uptake of carnitine. The disease is characterized by Reye syndrome, progressive cardiomyopathy, skeletal myopathy, hypoglycaemia and hyperammonaemia. CDSP is a treatable disease provided an early diagnosis is made and prompt treatment with L‐carnitine is initiated. The biochemical diagnosis of the disease is based on the findings of very low plasma and tissue carnitine concentrations. Recently, a human gene, SLC22A5, encoding a sodium‐dependent high‐affinity carnitine transporter OCTN2 was cloned from human kidney and shown to be mutated in systemic carnitine deficiency. Here we report two unrelated Saudi CDSP patients who were detected by tandem mass spectrometric analysis (MS/MS) of blood spots. Studies in skin fibroblasts from the two patients showed a severely reduced carnitine uptake. Subsequent molecular studies led to the identification of two novel missense mutations in the OCTN2 gene in the two patients.

Experimental Eye Research, Dec 1, 2022

Journal of Food Engineering, Jun 1, 2018

An existing two layer evaporation/diffusion model of thin layer drying was modified to incorporat... more An existing two layer evaporation/diffusion model of thin layer drying was modified to incorporate shrinkage. The model was developed and tested for a heat pump test dryer using cylindrical slices of banana, which were dried as a single layer. Shrinkage and drying data were collected over a range of conditions from 28 to 38 C and 12e30% relative humidity. In addition, models of depletion of key aroma volatiles were developed, to allow prediction of aroma profiles under different drying conditions. It was found that inclusion of shrinkage significantly improved the goodness of fit of the drying model, with shrinkage in the direction of slice thickness found to have a greater effect on drying rates than shrinkage in the radial direction. Aroma profiles were compared at different drying intervals, using four banana flavor compounds as indicators. Volatile depletion during drying was found to approximate a first order kinetic reaction with exponential decay over short periods.

Desalination, Sep 1, 2002

Sydney 2052, Crossflow ultrafiltration of binary protein solutions was carried out using flux-ste... more Sydney 2052, Crossflow ultrafiltration of binary protein solutions was carried out using flux-stepping and constant flux experiments to identify the apparent critical flux where fouling is rapid. The contributions of individual protein species to the apparent critical flux were evaluated as well as the separation performance. For mixtures of g& globulin/lysozyme and BSA/lysozyme the larger retained protein tended to control the critical flux behaviour while the observed rejection of the smaller transmitted protein went through a minimum close to the apparent critical flux. Identification of the respective protein species deposited onto membrane surfaces was carried out using Matrix-Assisted Laser Desorption Ionisation Mass Spectroscopy (MALDI-MS). Mass spectra showed that the transmitted proteins resulted in a higher incidence of peaks relative to the retained proteins. This was thought to be the result of desorption of proteins from the membrane surface, from inside pores and from the membrane substrate. It was shown that the MALDI-MS technique is a powerful tool for distinguishing between different proteins in fouling deposits and has potential for quantitative measurement of protein fouling on membrane surfaces.

Food Chemistry, Nov 1, 2019

Co-ingestion of red cabbage with cherry tomato enhances digestive bioaccessibility of anthocyanin... more Co-ingestion of red cabbage with cherry tomato enhances digestive bioaccessibility of anthocyanins but decreases carotenoid bioaccessibility after simulated in vitro gastro-intestinal digestion

Evidence of the effect of molecule size (molecular sieving) was discovered in leak channels simil... more Evidence of the effect of molecule size (molecular sieving) was discovered in leak channels similar to those found in hermetically sealed implantable bionics. A range of test gases of different molecular sizes was used to investigate the relative leak rates of several different samples. A contemporary model of molecular sieving is shown to be in partial agreement with our data.

bioRxiv (Cold Spring Harbor Laboratory), Nov 16, 2020

The dingo is Australia's iconic top-order predator and arrived on the continent between 5,000-8,0... more The dingo is Australia's iconic top-order predator and arrived on the continent between 5,000-8,000 years ago. To provide an unbiased insight into its evolutionary affiliations and biological interactions, we coupled long-read DNA sequencing with a multiplatform scaffolding approach to produce an ab initio genome assembly of the desert dingo (85X coverage) we call CanLup_DDS. We compared this genome to the Boxer (CanFam3.1) and German Shepherd dog (CanFam_GSD) assemblies and characterized lineage-specific and shared genetic variation ranging from single-to megabase pair-sized variants. We identified 21,483 dingo-specific and 16,595 domestic dog-specific homozygous structural variants mediating genic and putative regulatory changes. Comparisons between the dingo and domestic dog builds detected unique inversions on Chromosome 16, structural variations in genes linked with starch metabolism, and seven differentially methylated genes. To Main Australia has the worst mammalian extinction rate of any country in the world and the catastrophic bushfires of 2019-20 have fast tracked multiple species towards extinction. Concomitant with public education a strategic priority must be to restore ecosystem balance. One approach to restoring ecosystems and to conferring resilience against globally threatening processes is to develop our understanding of the functionality of predators 1. Dingoes have been the Australia's apex predator since their arrival 5,000-8,000 years ago 2,3. They show a unique suite of behavioural traits including scent-marking for social communication, territory defence and to synchronise reproduction. Historically, they fed on a marsupials and reptiles. In native ecosystems, they tend to consume the most prevalent species 4. In disturbed environments dingoes eat prey of increasing body size as aridity increases 5. This opportunistic hunting has brought the dingo into conflict with pastoralists and feral dogs. To resolve the debate around the ecological role of dingoes in the Australian ecosystem it is crucial to identify the structural and functional genetic differences that distinguish them from feralised domestic dogs. To date, genomic studies have been based on mapping re-sequenced genomes to the domestic dog reference genome 6-9. The alignment of re-sequenced data to a single reference genome underestimates species-specific variation, yet computational analyses have established the dingo genome harbours multiple positively selected genes related to metabolism 6,10,11. Further, dingoes have retained the ancestral pancreatic amylase AMY2B copy number (n=2) with one or more copy number expansions in domestic dogs 10. We explore the genomic divergence between a desert dingo and two domestic dog breeds and experimentally consider whether differences in the biochemistry, .

Biotechnology and Bioengineering, 2003

Binary aqueous solutions of bovine serum albumin (BSA) and h-lactoglobulin (bLG) were subject to ... more Binary aqueous solutions of bovine serum albumin (BSA) and h-lactoglobulin (bLG) were subject to flux-stepping and constant flux ultrafiltration to identify the apparent critical flux and to study the mechanisms and factors affecting fouling when the membrane is permeable to one protein component. Membranes from these filtration experiments were analyzed using matrixassisted laser desorption ionization mass spectrometry (MALDI-MS) to locate and quantify levels of fouling below and above the apparent critical flux. Hydrophilic (PLTK) regenerated cellulose and hydrophobic (PBTK) polysulfone asymmetric membranes were used, both of 30 kDa nominal molecular weight cutoff. For the hydrophilic PLTK membrane, protein deposition was shown to depend on electrostatic forces, exhibiting little or no fouling when the proteins had the same charge sign as that of the membrane. This was found to apply for both dilute equal mass-per-unit-volume and equimolar binary mixtures. For the PBTK membrane, hydrophobic proteinmembrane attractive forces were sufficiently strong to cause deposition of bLG even in the presence of repulsive electrostatic forces. For the PBTK membrane deposition exceeded monolayer coverage below and above apparent critical flux conditions but for the PLTK membrane this generally occurred when the apparent critical flux was exceeded. MALDI-MS was shown to be a facile direct analytical technique for individually quantifying adsorbed proteins on membrane surfaces at levels as low as 50 fmol/mm 2. The high levels of compound specificity inherent to mass spectrometry make this approach especially suited to the quantification of individual components in mixed deposits. In this study, MALDI-MS was found to be successful in identifying and quantifying the protein species responsible for fouling.

Journal of Lipid Research, Mar 1, 2014

The Biological Bulletin, Jun 1, 2004

Critical Reviews in Food Science and Nutrition, Jul 21, 2017

The combinations of two or more phytochemicals bring about changes in the ultimate biological eff... more The combinations of two or more phytochemicals bring about changes in the ultimate biological effects and/or the bioavailability of each component. A number of mixtures of pure bioactive compounds or phytochemical-containing plant extracts provide synergy with regard to antioxidant status, anti-inflammation, anti-cancer and chemoprevention of several oxidative stress and metabolic disorders in vitro. The biological activities of food phytochemicals depend upon their bioaccessibility and bioavailability which can be affected by the presence of other food components including other bioactive constituents. The interactions between phytochemicals during intestinal absorption could result in changes in the bioavailability of the compounds, which in turn affects the intensity of their bioactivities. This paper provides an overview of combined biological effects of phytochemical mixtures derived from fruits and vegetables with a focus on anti-oxidative, anti-inflammatory and anti-carcinogenic activities. The bioavailability impairment or enhancement caused by the co-consumption of dietary phytochemicals is also discussed. Finally, research gaps for future studies on phytochemical interactions are identified.

Clinical Chemistry, Jul 1, 1997

Metabolic profiling of amino acids and acylcarnitines from blood spots by automated electrospray ... more Metabolic profiling of amino acids and acylcarnitines from blood spots by automated electrospray tandem mass spectrometry (ESI-MS/MS) is a powerful diagnostic tool for inborn errors of metabolism. New approaches to sample preparation and data interpretation have helped establish the methodology as a robust, high-throughput neonatal screening method. We introduce an efficient 96-well-microplate batch process for blood-spot sample preparation, with which we can obtain high-quality profiles from 500-1000 samples per day per instrument. A computer-assisted metabolic profiling algorithm automatically flags abnormal profiles. We selected diagnostic parameters for the algorithm by comparing profiles from patients with known metabolic disorders and those from normal newborns. Reference range and cutoff values for the diagnostic parameters were established by measuring either metabolite concentrations or peak ratios of certain metabolite pairs. Rigorous testing of the algorithm demonstrates its outstanding clinical sensitivity in flagging abnormal profiles and its high cumulative specificity. INDEXING TERMS: amino acids • organic acidemia • defects of fatty acid oxidation • inherited disorders • neonatal screening Departments of

Experimental Eye Research, Feb 1, 2019

The research complied with the tenets of the declaration of Helsinki. Informed consent was obtain... more The research complied with the tenets of the declaration of Helsinki. Informed consent was obtained from all participants who provided tear samples.

Food Research International, Apr 1, 2018

Headspace gas chromatography mass spectrometry (HS-GC-MS) was used to measure changes in selected... more Headspace gas chromatography mass spectrometry (HS-GC-MS) was used to measure changes in selected volatile flavour compounds in fresh banana during low temperature heat pump drying. Ten compounds from a range of chemical classes were measured during drying at three different drying conditions. Ester compounds were found to be the most affected, with losses varying from 25 to 87% during drying. Three patterns of depletion were observed in this study. Ester and aldehyde levels reduced quickly during the early stages of drying, but levels stabilised at non-zero values towards the end of drying; alcohol levels initially increased, then decreased and stabilised; whilst high molecular weight compounds, such as elemicine and eugenol, were not affected significantly. Selective diffusion and volatility affected the degree of flavour retention.

ChemInform, Feb 16, 2015

An Easy One-Pot Synthesis of Diverse 2,5-Di(2-pyridyl)pyrroles: A Versatile Entry Point to Metal ... more An Easy One-Pot Synthesis of Diverse 2,5-Di(2-pyridyl)pyrroles: A Versatile Entry Point to Metal Complexes of Functionalized, Meridial and Tridentate 2,5-Di(2-pyridyl)pyrrolato Ligands.-Although only moderate yields are obtained an easy one-pot route to 2,5-dipyridylpyrrole ligands (IV) is described. Incorporation of the ligands into Pd-and Ru-complexes is investigated as well as the electrochemical properties of these complexes.-(MCSKIMMING, A.; DIACHENKO, V.;

Journal of Functional Foods, Jun 1, 2018

This study investigated the bioactivity interactions in vitro and ex vivo, and cellular uptake in... more This study investigated the bioactivity interactions in vitro and ex vivo, and cellular uptake interaction between βcarotene and some common anthocyanins. The combined antioxidant and anti-inflammatory activities of βcarotene and different anthocyanins were assessed in both chemical and biological systems. Bioactivity synergy was seen in none of the combinations in no system studied. Some mixtures even showed antagonistic effects. All of the tested anthocyanins except for delphinidin-3-glucoside, tested at 7.5 μM, significantly improved the cellular uptake of β-carotene (2.5 μM) by 68-200% although such increases of β-carotene intracellular content did not lead to an enhancement of the combined bioactivities. The increase of β-carotene absorption to a particular concentration facilitated the pro-oxidant activity of β-carotene. This effect could be partly responsible for the bioactivity antagonism seen in some of the combinations.

Science, Jun 19, 2020

Perovskite decomposition in detail Solar cells are subject to heating when operating in sunlight,... more Perovskite decomposition in detail Solar cells are subject to heating when operating in sunlight, and the organic components of hybrid perovskite solar cells, especially the commonly used methylammonium cation, can undergo thermal decomposition. Encapsulation can limit decomposition by bringing such reactions to equilibrium and can prevent exposure to damaging ambient moisture. Shi et al. examined several encapsulation schemes for perovskite films and devices by probing volatile products with gas chromatography–mass spectrometry (see the Perspective by Juarez-Perez and Haro). Pressure-tight polymer/glass stack encapsulation was effective in suppressing gas transfer and allowed solar cells containing methylammonium to pass harsh moisture and thermal cycling tests. Science , this issue p. eaba2412 ; see also p. 1309

Investigative Ophthalmology & Visual Science, Jun 23, 2017

European Chemical Bulletin, Nov 9, 2012

Low temperature molten salts based on ionic liquids have received considerable attention over the... more Low temperature molten salts based on ionic liquids have received considerable attention over the last 3 decades as potential alternative solvents for aluminium reduction. Recent reports in the literature have identified 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl) amide ([C 3 mpip][NTf 2 ]) as a promising candidate for low temperature aluminium reduction processes. The formation of aluminium metal deposition was confirmed in these studies by both visual inspection and SEM-EDX analysis in the selected mixtures with AlCl 3 , but little is known about the anodic processes occurring in the cell. This work presents the results of a preliminary electrochemical study of the anodic and cathodic reactions occurring in the ionic liquid mixtures 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)amide ([C 3 mpip][NTf 2 ]) with AlCl 3 at different temperatures, concentrations and electrode materials. Analysis of voltammetric responses of [C 3 mpip][NTf 2 ]-[AlCl 3 ] x for x=0.3 indicated that the anodic process is limited by mass transport for this particular electrolyte composition. In addition, the formation of Cl 2 was confirmed to take place at a dimensionally stable anode. Aluminium deposition experiments gave inconsistent results however and gas analysis indicated that the [C 3 mpip][NTf 2 ]-[AlCl 3 ] x mixture at a prolonged elevated temperature at least partially decomposes into fluoro-carbons and chloro-compounds.

Chemical Communications, 2017

A new ruthenium(ii) complex capable of catalysing both CO2 reduction and water oxidation was desi... more A new ruthenium(ii) complex capable of catalysing both CO2 reduction and water oxidation was designed and synthesised. The electro-catalytic efficiency and robustness of the complex together with the electronic effect of its co-ligands were investigated to develop next generation dual activity electrocatalysts.

Journal of Inherited Metabolic Disease, Sep 1, 2002

Systemic carnitine deficiency (CDSP) (McKusick 212140) is a rare autosomal recessive disease caus... more Systemic carnitine deficiency (CDSP) (McKusick 212140) is a rare autosomal recessive disease caused by defective plasma membrane uptake of carnitine. The disease is characterized by Reye syndrome, progressive cardiomyopathy, skeletal myopathy, hypoglycaemia and hyperammonaemia. CDSP is a treatable disease provided an early diagnosis is made and prompt treatment with L‐carnitine is initiated. The biochemical diagnosis of the disease is based on the findings of very low plasma and tissue carnitine concentrations. Recently, a human gene, SLC22A5, encoding a sodium‐dependent high‐affinity carnitine transporter OCTN2 was cloned from human kidney and shown to be mutated in systemic carnitine deficiency. Here we report two unrelated Saudi CDSP patients who were detected by tandem mass spectrometric analysis (MS/MS) of blood spots. Studies in skin fibroblasts from the two patients showed a severely reduced carnitine uptake. Subsequent molecular studies led to the identification of two novel missense mutations in the OCTN2 gene in the two patients.

Experimental Eye Research, Dec 1, 2022

Journal of Food Engineering, Jun 1, 2018

An existing two layer evaporation/diffusion model of thin layer drying was modified to incorporat... more An existing two layer evaporation/diffusion model of thin layer drying was modified to incorporate shrinkage. The model was developed and tested for a heat pump test dryer using cylindrical slices of banana, which were dried as a single layer. Shrinkage and drying data were collected over a range of conditions from 28 to 38 C and 12e30% relative humidity. In addition, models of depletion of key aroma volatiles were developed, to allow prediction of aroma profiles under different drying conditions. It was found that inclusion of shrinkage significantly improved the goodness of fit of the drying model, with shrinkage in the direction of slice thickness found to have a greater effect on drying rates than shrinkage in the radial direction. Aroma profiles were compared at different drying intervals, using four banana flavor compounds as indicators. Volatile depletion during drying was found to approximate a first order kinetic reaction with exponential decay over short periods.

Desalination, Sep 1, 2002

Sydney 2052, Crossflow ultrafiltration of binary protein solutions was carried out using flux-ste... more Sydney 2052, Crossflow ultrafiltration of binary protein solutions was carried out using flux-stepping and constant flux experiments to identify the apparent critical flux where fouling is rapid. The contributions of individual protein species to the apparent critical flux were evaluated as well as the separation performance. For mixtures of g& globulin/lysozyme and BSA/lysozyme the larger retained protein tended to control the critical flux behaviour while the observed rejection of the smaller transmitted protein went through a minimum close to the apparent critical flux. Identification of the respective protein species deposited onto membrane surfaces was carried out using Matrix-Assisted Laser Desorption Ionisation Mass Spectroscopy (MALDI-MS). Mass spectra showed that the transmitted proteins resulted in a higher incidence of peaks relative to the retained proteins. This was thought to be the result of desorption of proteins from the membrane surface, from inside pores and from the membrane substrate. It was shown that the MALDI-MS technique is a powerful tool for distinguishing between different proteins in fouling deposits and has potential for quantitative measurement of protein fouling on membrane surfaces.

Food Chemistry, Nov 1, 2019

Co-ingestion of red cabbage with cherry tomato enhances digestive bioaccessibility of anthocyanin... more Co-ingestion of red cabbage with cherry tomato enhances digestive bioaccessibility of anthocyanins but decreases carotenoid bioaccessibility after simulated in vitro gastro-intestinal digestion

Evidence of the effect of molecule size (molecular sieving) was discovered in leak channels simil... more Evidence of the effect of molecule size (molecular sieving) was discovered in leak channels similar to those found in hermetically sealed implantable bionics. A range of test gases of different molecular sizes was used to investigate the relative leak rates of several different samples. A contemporary model of molecular sieving is shown to be in partial agreement with our data.

bioRxiv (Cold Spring Harbor Laboratory), Nov 16, 2020

The dingo is Australia's iconic top-order predator and arrived on the continent between 5,000-8,0... more The dingo is Australia's iconic top-order predator and arrived on the continent between 5,000-8,000 years ago. To provide an unbiased insight into its evolutionary affiliations and biological interactions, we coupled long-read DNA sequencing with a multiplatform scaffolding approach to produce an ab initio genome assembly of the desert dingo (85X coverage) we call CanLup_DDS. We compared this genome to the Boxer (CanFam3.1) and German Shepherd dog (CanFam_GSD) assemblies and characterized lineage-specific and shared genetic variation ranging from single-to megabase pair-sized variants. We identified 21,483 dingo-specific and 16,595 domestic dog-specific homozygous structural variants mediating genic and putative regulatory changes. Comparisons between the dingo and domestic dog builds detected unique inversions on Chromosome 16, structural variations in genes linked with starch metabolism, and seven differentially methylated genes. To Main Australia has the worst mammalian extinction rate of any country in the world and the catastrophic bushfires of 2019-20 have fast tracked multiple species towards extinction. Concomitant with public education a strategic priority must be to restore ecosystem balance. One approach to restoring ecosystems and to conferring resilience against globally threatening processes is to develop our understanding of the functionality of predators 1. Dingoes have been the Australia's apex predator since their arrival 5,000-8,000 years ago 2,3. They show a unique suite of behavioural traits including scent-marking for social communication, territory defence and to synchronise reproduction. Historically, they fed on a marsupials and reptiles. In native ecosystems, they tend to consume the most prevalent species 4. In disturbed environments dingoes eat prey of increasing body size as aridity increases 5. This opportunistic hunting has brought the dingo into conflict with pastoralists and feral dogs. To resolve the debate around the ecological role of dingoes in the Australian ecosystem it is crucial to identify the structural and functional genetic differences that distinguish them from feralised domestic dogs. To date, genomic studies have been based on mapping re-sequenced genomes to the domestic dog reference genome 6-9. The alignment of re-sequenced data to a single reference genome underestimates species-specific variation, yet computational analyses have established the dingo genome harbours multiple positively selected genes related to metabolism 6,10,11. Further, dingoes have retained the ancestral pancreatic amylase AMY2B copy number (n=2) with one or more copy number expansions in domestic dogs 10. We explore the genomic divergence between a desert dingo and two domestic dog breeds and experimentally consider whether differences in the biochemistry, .

Biotechnology and Bioengineering, 2003

Binary aqueous solutions of bovine serum albumin (BSA) and h-lactoglobulin (bLG) were subject to ... more Binary aqueous solutions of bovine serum albumin (BSA) and h-lactoglobulin (bLG) were subject to flux-stepping and constant flux ultrafiltration to identify the apparent critical flux and to study the mechanisms and factors affecting fouling when the membrane is permeable to one protein component. Membranes from these filtration experiments were analyzed using matrixassisted laser desorption ionization mass spectrometry (MALDI-MS) to locate and quantify levels of fouling below and above the apparent critical flux. Hydrophilic (PLTK) regenerated cellulose and hydrophobic (PBTK) polysulfone asymmetric membranes were used, both of 30 kDa nominal molecular weight cutoff. For the hydrophilic PLTK membrane, protein deposition was shown to depend on electrostatic forces, exhibiting little or no fouling when the proteins had the same charge sign as that of the membrane. This was found to apply for both dilute equal mass-per-unit-volume and equimolar binary mixtures. For the PBTK membrane, hydrophobic proteinmembrane attractive forces were sufficiently strong to cause deposition of bLG even in the presence of repulsive electrostatic forces. For the PBTK membrane deposition exceeded monolayer coverage below and above apparent critical flux conditions but for the PLTK membrane this generally occurred when the apparent critical flux was exceeded. MALDI-MS was shown to be a facile direct analytical technique for individually quantifying adsorbed proteins on membrane surfaces at levels as low as 50 fmol/mm 2. The high levels of compound specificity inherent to mass spectrometry make this approach especially suited to the quantification of individual components in mixed deposits. In this study, MALDI-MS was found to be successful in identifying and quantifying the protein species responsible for fouling.

Journal of Lipid Research, Mar 1, 2014

The Biological Bulletin, Jun 1, 2004

Critical Reviews in Food Science and Nutrition, Jul 21, 2017

The combinations of two or more phytochemicals bring about changes in the ultimate biological eff... more The combinations of two or more phytochemicals bring about changes in the ultimate biological effects and/or the bioavailability of each component. A number of mixtures of pure bioactive compounds or phytochemical-containing plant extracts provide synergy with regard to antioxidant status, anti-inflammation, anti-cancer and chemoprevention of several oxidative stress and metabolic disorders in vitro. The biological activities of food phytochemicals depend upon their bioaccessibility and bioavailability which can be affected by the presence of other food components including other bioactive constituents. The interactions between phytochemicals during intestinal absorption could result in changes in the bioavailability of the compounds, which in turn affects the intensity of their bioactivities. This paper provides an overview of combined biological effects of phytochemical mixtures derived from fruits and vegetables with a focus on anti-oxidative, anti-inflammatory and anti-carcinogenic activities. The bioavailability impairment or enhancement caused by the co-consumption of dietary phytochemicals is also discussed. Finally, research gaps for future studies on phytochemical interactions are identified.

Clinical Chemistry, Jul 1, 1997

Metabolic profiling of amino acids and acylcarnitines from blood spots by automated electrospray ... more Metabolic profiling of amino acids and acylcarnitines from blood spots by automated electrospray tandem mass spectrometry (ESI-MS/MS) is a powerful diagnostic tool for inborn errors of metabolism. New approaches to sample preparation and data interpretation have helped establish the methodology as a robust, high-throughput neonatal screening method. We introduce an efficient 96-well-microplate batch process for blood-spot sample preparation, with which we can obtain high-quality profiles from 500-1000 samples per day per instrument. A computer-assisted metabolic profiling algorithm automatically flags abnormal profiles. We selected diagnostic parameters for the algorithm by comparing profiles from patients with known metabolic disorders and those from normal newborns. Reference range and cutoff values for the diagnostic parameters were established by measuring either metabolite concentrations or peak ratios of certain metabolite pairs. Rigorous testing of the algorithm demonstrates its outstanding clinical sensitivity in flagging abnormal profiles and its high cumulative specificity. INDEXING TERMS: amino acids • organic acidemia • defects of fatty acid oxidation • inherited disorders • neonatal screening Departments of

Solar cells are subject to heating when operating in sunlight, and the organic components of hyb... more Solar cells are subject to heating when operating in sunlight, and the organic components of hybrid perovskite solar cells, especially the commonly used methylammonium cation, can undergo thermal decomposition. Encapsulation can limit decomposition by bringing such reactions to equilibrium and can prevent exposure to damaging ambient moisture. Shi et al. examined several encapsulation schemes for perovskite films and devices by probing volatile products with gas chromatography–mass spectrometry (see the Perspective by Juarez-Perez and Haro). Pressure-tight polymer/glass stack encapsulation was effective in suppressing gas transfer and allowed solar cells containing methylammonium to pass harsh moisture and thermal cycling tests. Science, this issue p. eaba2412; see also p. 1309 Volatile emissions of encapsulated stable perovskite solar cells that passed harsh humidity and heating tests were analyzed. Although perovskite solar cells have produced remarkable energy conversion efficiencies, they cannot become commercially viable without improvements in durability. We used gas chromatography–mass spectrometry (GC-MS) to reveal signature volatile products of the decomposition of organic hybrid perovskites under thermal stress. In addition, we were able to use GC-MS to confirm that a low-cost polymer/glass stack encapsulation is effective in suppressing such outgassing. Using such an encapsulation scheme, we produced multi-cation, multi-halide perovskite solar cells containing methylammonium that exceed the requirements of the International Electrotechnical Commission 61215:2016 standard by surviving more than 1800 hours of the Damp Heat test and 75 cycles of the Humidity Freeze test.