Marked Transition Research Articles

High protein and cholesterol intakes associated with emergence of glucose intolerance in a low-risk Canadian Inuit population.

The rate of type 2 diabetes mellitus among Inuit is 12·2 % in individuals over 50 years of age, similar to the Canadian prevalence. Given marked dietary transitions in the Arctic, we evaluated the dietary and other correlates of not previously diagnosed glucose intolerance, defined as type 2 diabetes mellitus, impaired fasting glucose or impaired glucose tolerance. Cross-sectional analyses were limited to adults with a completed 2 h oral glucose tolerance test and without pre-existing diabetes. Anthropometric assessments, health and medication usage questionnaires and a 24 h dietary recall were administered. Canadian International Polar Year Inuit Health Survey (2007-2008). Inuit adults (n 777). Glucose intolerance was associated with older age and adiposity. Percentage of energy from protein above the Acceptable Macronutrient Distribution Range of 35 %, compared with intake within the range, was associated with increased odds of glucose intolerance (OR=1·98; 95 % CI 1·09, 3·61) in multivariable analyses. Further, cholesterol intake in the highest three quartiles combined (median exposures of 207, 416 and 778 mg/d, respectively) compared with the lowest quartile (median intake of 81 mg/d) was associated with glucose intolerance (OR=2·15; 95 % CI 1·23, 3·78) in multivariable analyses. Past-day traditional food consumption was borderline protective of glucose intolerance (P=0·054) and high fibre intake was not significantly protective (P=0·08). The results contribute to the existing literature on high protein and cholesterol intakes as they may relate to diabetes risk.

Duplex formation and secondary structure of γ-PNA observed by NMR and CD

Peptide nucleic acids (PNAs) are non-natural oligonucleotides mimics, wherein the phosphoribose backbone has been replaced by a peptidic moiety (N-(2-aminoethyl)glycine). This peptidic backbone lends itself to substitution and the γ-position has proven to yield oligomers with enhanced hybridization properties. In this study, we use Nuclear Magnetic Resonance (NMR) and Circular Dichroism (CD) to explore the properties of the supramolecular duplexes formed by these species. We show that standard Watson–Crick base pair as well as non-standard ones are formed in solution. The duplexes thus formed present marked melting transition temperatures substantially higher than their nucleic acid homologs. Moreover, the presence of a chiral group on the γ-peptidic backbone increases further this transition temperature, leading to very stable duplexes.PNA duplexes with a chiral backbone present a marked chiral secondary structure, observed by CD, and showing a common folding pattern for all studied structures. Nevertheless small differences are observed depending on the details of the nucleobase sequence.

New oil modified acrylic polymer for pH sensitive drug release: Experimental results and statistical analysis

We report results of an experimental study, complemented by detailed statistical analysis of the experimental data, on the development of a more effective control method of drug delivery using a pH sensitive acrylic polymer. New copolymers based on acrylic acid and fatty acid are constructed from dodecyl castor oil and a tercopolymer based on methyl methacrylate, acrylic acid and acryl amide were prepared using this new approach. Water swelling characteristics of fatty acid, acrylic acid copolymer and tercopolymer respectively in acid and alkali solutions have been studied by a step-change method. The antibiotic drug cephalosporin and paracetamol have also been incorporated into the polymer blend through dissolution with the release of the antibiotic drug being evaluated in bacterial stain media and buffer solution. Our results show that the rate of release of paracetamol getss affected by the pH factor and also by the nature of polymer blend. Our experimental data have later been statistically analyzed to quantify the precise nature of polymer decay rates on the pH density of the relevant polymer solvents. The time evolution of the polymer decay rates indicate a marked transition from a linear to a strictly non-linear regime depending on the whether the chosen sample is a general copolymer (linear) or a tercopolymer (non-linear). Non-linear data extrapolation techniques have been used to make probabilistic predictions about the variation in weight percentages of retained polymers at all future times, thereby quantifying the degree of efficacy of the new method of drug delivery.

Inhibitory effects of Lactobacillus fermentum on microbial growth and biofilm formation.

Beneficial effects of Lactobacilli have been reported, and lactic bacteria are employed for conservation of foods. Therefore, the effects of a Lactobacillus fermentum strain were analyzed regarding inhibitory effects on staphylococci, Candida albicans and enterotoxigenic enterobacteria by transmission electron microscopy (TEM). TEM of bacterial biofilms was performed using cocultures of bacteriocin-producing L. fermentum 97 with different enterotoxigenic strains: Staphylococcus epidermidis expressing the ica gene responsible for biofilm formation, Staphylococcus aureus producing enterotoxin type A, Citrobacter freundii, Enterobacter cloaceae, Klebsiella oxytoca, Proteus mirabilis producing thermolabile and thermostable enterotoxins determined by elt or est genes, and Candida albicans. L. fermentum 97 changed morphological features and suppressed biofilm formation of staphylococci, enterotoxigenic enterobacteria and Candida albicans; a marked transition to resting states, a degradation of the cell walls and cytoplasm, and a disruption of mature bacterial biofilms were observed, the latter indicating efficiency even in the phase of higher cell density.

Experimental study of gas flow characteristics in vertical tank for sinter waste heat recovery

In the present study, the dimensionless method of Ergun's correlation is used to investigate the flow regimes and the pressure drop characteristics in the packed beds with non-spherical sinter particles. The sinter particles of average diameter d = 6, 14, 24 and 35 mm, with a range of sphericity, 0.63≤Φ ≤ 0.89 are used in random packing with the range of bed layer voidage, 0.423≤ε ≤ 0.53. The pressure drop of unit bed layer height in the packed bed is measured with particle Reynolds number (Rep) ranging from 96 to 6888. The influences of gas superficial velocity and particle diameter on the pressure drop are analyzed in detail for the covered test cases. The critical Reynolds numbers marking transition among flow regimes and the revised Ergun's correlation are obtained according to the slope change of the fp–Rep curve and the regression analysis of experimental data. The reliability of the revised Ergun's correlation is also verified. It is found that, the pressure drop of unit bed layer height gradually increases as a quadratic relationship with increasing gas superficial velocity for a given particle diameter. The pressure drop of unit bed layer height decreases as exponential relationship with the increase of particle diameter for a given gas superficial velocity. The air flow in vertical tank with sinter particles is under non-Darcy flow area for the actual condition and the critical Reynolds number marking transition from Forchheimer flow to turbulent flow in sinter bed layer increases as a third order relationship with increasing particle equivalent diameter. Compared with the previous Ergun's correlations, the revised Ergun's correlation is able to fit the whole experimental data best, and the mean deviation between the experimental data and the values calculated by the revised Ergun's correlation is 7.22%, showing good prediction.

Abstract 1488: In vivo magnetic resonance elastography in pediatric brain tumor models

Abstract Refined imaging strategies that could improve diagnosis and management of children with brain malignancies are urgently required. Pediatric brain malignancies possess distinct underlying biologies that discriminate them from adult tumors, even within a common neuropathological diagnosis such as glioblastoma (GBM). Magnetic resonance elastography (MRE) exploits the ability of MRI to visualize the propagation of shear waves resulting from vibrations applied to the cranium to map and quantify (kPa) brain tissue elasticity (Gd) and viscosity (Gl) in vivo. The altered viscoelastic properties of tumors, combined with the sensitivity of MRE for differences in tumor microstructure, establishes MRE as an attractive modality for the detection and differential diagnosis of brain malignancies. Here we aimed to determine whether the potential of MRE in the neuroradiological management of patients with brain malignancies could be extended to the pediatric population. The viscoelastic properties of two pediatric brain tumor models that faithfully emulate high risk childhood disease were investigated: i) Orthotopic D-212 MG pediatric supratentorial giant cell GBM (H3F3A wildtype, 11 year old patient) xenografts propagated in NCr nu/nu mice and ii) GTML/Trp53KI/KI transgenic mice that spontaneously develop aggressive, MYCN driven, p53 depleted, medulloblastomas. D-212 MG and GTML/Trp53KI/KI tumors were less elastic (lower Gd) and viscous (lower Gl), and therefore softer, than the surrounding brain tissue. Both tumor types were also significantly less elastic (D-212 MG Gd = 3.9±0.2; GTML/Trp53KI/KI Gd = 3.5±0.1) than the soft thalamic parenchyma in non-tumor-bearing mice (Gd = 5.9±0.2; p = 0.001 and p = 0.02, respectively, Mann-Whitney), in addition to being less viscous. Interestingly, GTML/Trp53KI/KI tumors demonstrated a bimodal distribution of Gd, which reflected the more marked transition between their relatively stiffer rim and the softer core compared with D-212 MG tumors. We demonstrate that two representative models of major high risk pediatric brain malignancies share the unique softness previously observed in adult brain tumor models, allowing their detection by MRE. This supports observations that pediatric GBMs are morphologically indistinguishable from adult GBMs. Although median Gd values were not sufficient to discriminate between the tumor types, the marked bimodal distribution of Gd in the GTML/Trp53KI/KI tumors was not apparent in D-212 MG GBM tumors. Whilst ongoing histopathological investigation into growth patterns, vascular, cellular and extracellular networks will aid elucidation of the pathological determinants of the bimodal signature, to date unique to GTML/Trp53KI/KI, these data reinforce the potential of MRE for the detection and differential diagnosis of pediatric brain malignancies based on their mechanical properties. Citation Format: Jin Li, Jessica K.R. Boult, Maria Vinci, Sergey Popov, Karen Barker, Zai Ahmad, Yann Jamin, Craig Cummings, Suzanne A. Eccles, Jeffrey C. Bamber, Ralph Sinkus, Louis Chesler, Chris Jones, Simon P. Robinson. In vivo magnetic resonance elastography in pediatric brain tumor models. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1488. doi:10.1158/1538-7445.AM2015-1488

The double burden of under- and overnutrition and nutrient adequacy among Chinese preschool and school-aged children in 2009-2011.

Coincident with economic development, China has experienced a marked transition from undernutrition to overweight/obesity over the last few decades. We aimed to explore the burden of under- and overnutrition and nutrient adequacy among 2-12-year-old Chinese children. We included anthropometry, dietary intake and biomarkers from 2-12-year-olds who participated in the 2009-2011 China Health and Nutrition Survey (n=1191 in 2009; n=1648 in 2011). Dietary intakes were compared with the 2013 Chinese Dietary Recommended Intakes. In 2011, ~19% of 2-6-year-old children were underweight, 4% were stunted, 10% were overweight and 12% were obese. Among 7-12-year-old children, stunting was almost 0%, whereas ~21% were underweight, 13% were overweight and 6% were obese in 2011. Overweight and obesity were more prevalent among children from urban areas and higher income households. In particular, 2-6-year-old children from urban areas and higher income households experienced the highest increase in obesity from 2009 to 2011 (P<0.05). Children from urban areas and higher income households had overall higher intakes of total daily energy and most macro- and micronutrients (P<0.05). However, a significant proportion of children did not meet the recommendations for important micronutrients. Underweight and stunting currently coexist with overweight and obesity among Chinese children <12-year-old. We found critical disparities in the prevalence of under- and overweight/obesity, as well as in nutrient intakes and dietary adequacies between children from different incomes, revealing that the burden of childhood under- and overnutrition may constitute a public health concern in modern China.

Finding Partisanship Where We Least Expect it: Evidence of Partisan Bias in a New African Democracy

Much of the literature on political behavior in Africa’s new semi-democracies has treated partisan affiliation as weak, purely pragmatic, or a proxy for other, more meaningful identities such as ethnicity. In this article, I dispute these conceptions by demonstrating that partisanship in an African context, like partisanship in established democracies, is a psychologically meaningful identity that can inspire voters to engage in motivated reasoning. By combining survey data with an original dataset of objective indicators of local public goods quality in Uganda, I show that supporters of the incumbent president systematically overestimate what they have received from government, while opposition supporters systematically underestimate. Partisan support precedes, rather than results from, this mis-estimation. I also show that partisans of the incumbent (opposition) are significantly more (less) likely to attribute any bad outcomes they observe to private actors rather than the government. I argue that these findings are consistent with the predictions of social identity theory: the conflict that marked many African political transitions, and the mapping of African parties onto existing social cleavages, are sufficient conditions for the creation of strong political-social identities like those that characterize partisanship in the West. My findings indicate that Africanists should take partisanship seriously as a predictor of political behavior and attitudes.

Structural, physiognomic and above-ground biomass variation in savanna–forest transition zones on three continents – how different are co-occurring savanna and forest formations?

Abstract. Through interpretations of remote-sensing data and/or theoretical propositions, the idea that forest and savanna represent "alternative stable states" is gaining increasing acceptance. Filling an observational gap, we present detailed stratified floristic and structural analyses for forest and savanna stands located mostly within zones of transition (where both vegetation types occur in close proximity) in Africa, South America and Australia. Woody plant leaf area index variation was related to tree canopy cover in a similar way for both savanna and forest with substantial overlap between the two vegetation types. As total woody plant canopy cover increased, so did the relative contribution of middle and lower strata of woody vegetation. Herbaceous layer cover declined as woody cover increased. This pattern of understorey grasses and herbs progressively replaced by shrubs as the canopy closes over was found for both savanna and forests and on all continents. Thus, once subordinate woody canopy layers are taken into account, a less marked transition in woody plant cover across the savanna–forest-species discontinuum is observed compared to that inferred when trees of a basal diameter &gt; 0.1 m are considered in isolation. This is especially the case for shrub-dominated savannas and in taller savannas approaching canopy closure. An increased contribution of forest species to the total subordinate cover is also observed as savanna stand canopy closure occurs. Despite similarities in canopy-cover characteristics, woody vegetation in Africa and Australia attained greater heights and stored a greater amount of above-ground biomass than in South America. Up to three times as much above-ground biomass is stored in forests compared to savannas under equivalent climatic conditions. Savanna–forest transition zones were also found to typically occur at higher precipitation regimes for South America than for Africa. Nevertheless, consistent across all three continents coexistence was found to be confined to a well-defined edaphic–climate envelope with soil and climate the key determinants of the relative location of forest and savanna stands. Moreover, when considered in conjunction with the appropriate water availability metrics, it emerges that soil exchangeable cations exert considerable control on woody canopy-cover extent as measured in our pan-continental (forest + savanna) data set. Taken together these observations do not lend support to the notion of alternate stable states mediated through fire feedbacks as the prime force shaping the distribution of the two dominant vegetation types of the tropical lands.

Quorum-Sensing Mechanisms Mediated by Farnesol in Ophiostoma piceae: Effect on Secretion of Sterol Esterase.

Ophiostoma piceae CECT 20416 is a dimorphic wood-staining fungus able to produce an extracellular sterol-esterase/lipase (OPE) that is of great biotechnological interest. In this work, we have studied the morphological change of this fungus from yeast to hyphae, which is associated with the cell density-related mechanism known as quorum sensing (QS), and how this affects the secretion of OPE. The data presented here confirm that the molecule E,E-farnesol accumulates as the cell number is growing within the population. The exogenous addition of this molecule or spent medium to the cultures increased the extracellular activity of OPE 2.5 times. This fact was related not to an increase in microbial biomass or in the expression of the gene coding for OPE but to a marked morphological transition in the cultures. Moreover, the morphological transition also occurred when a high cell density was inoculated into the medium. The results suggest that E,E-farnesol regulates through QS mechanisms the morphological transition in the dimorphic fungus O. piceae and that it is associated with a higher extracellular esterase activity. Furthermore, identification and transcriptional analysis of genes tup1 and cyr1, which are involved in the response, was carried out. Here we report enhanced production of a sterol-esterase/lipase of biotechnological interest by means of QS mechanisms. These results may be useful in increasing the production of secreted enzymes of other dimorphic fungi of biotechnological interest.

A case example of the importance of multi-analytical approach in deciphering carbonatite petrogenesis in South Qinling orogen: Miaoya rare-metal deposit, central China

The South Qinling orogen in central China hosts carbonatites occurring as stocks associated with syenites and collectively regarded as the Miaoya intrusive complex. The complex hosts economic resources of rare-earth elements (REE) and Nb. The Miaoya syenites are strongly metasomatized at the contact with the carbonatites and cross-cut by carbonate and felsic veinlets. Small oscillatory-zoned crystals of zircons from the syenites give a concordant U–Pb age of 147±0.5Ma, which differs significantly from the ages of both large magmatic zircon grains from the syenites and primary monazite from the carbonatites (766Ma and 234Ma, respectively). To account for the possibility that the Miaoya syenites are coeval and cogenetic with the carbonatites, the trace-element budget of both rock types was examined in detail. The Miaoya carbonatite contains primary REE-rich fluorapatite and monazite, which precipitated earlier than the rock-forming REE-poor calcite, indicating that the primary carbonatitic magma was rich in REE. The compositions of the parental syenitic and carbonatitic magmas, calculated on the basis of the trace-element composition of primary fluorapatite in the two rock suites, show that the carbonatitic magma contained higher Sr and REE (La–Tb), but lower Ba, Pb, Th, U, Nb and Ta levels in comparison with the syenitic melt. These differences are inconsistent with derivation of the Miaoya rocks from a homogeneous carbonate–silicate melt by immiscibility or crystal fractionation. It is therefore concluded that the carbonatitic magma at Miaoya was generated directly in the mantle. Emplacement of the carbonatites in the South Qinling orogen marked transition to a postorogenic regime, and was preceded by oceanic crust subduction and closure of the Mianlue Ocean in the Triassic. Our models show that melting of the Mianlue crust and up to 10wt.% of sediments cannot produce the levels of REE enrichment observed in the Miaoya carbonatites. More complex models, involving recycling of the Mianlue oceanic crust and a REE-rich carbonate liquid from an old deep-seated mantle source are required to explain the observed trace-element characteristics of the Miaoya carbonatites.

Revealing an intermediate region between the collisional radiofrequency plasma bulk and its sheath.

Experimental evidence of the existence of an intermediate region between a capacitively coupled plasma and the collisional space-charge region at its borders is presented. This proof is generated by monitoring-in an airplane carrying out parabolic flights-the trajectory of plasma-confined microparticles. Based on only primary data and without the need for a sophisticated model, our analysis concludes a sharply marked transition from the sheath region into another region with a significantly lower-yet nonzero-space-charge density, i.e., a region which is often called the presheath.

Parameter Estimation of Discrete Multivariate Phase-Type Distributions

This paper considers parameter estimation of a class of discrete multi-variate phase-type distributions (DMPH). Such discrete phase-type distributions are based on discrete Markov chains with marked transitions introduced by He and Neuts (Stoch Process Appl 74(1):37–52, 1998) and is a generalization of the discrete univariate phase–type distributions. Properties of the DMPHs are presented. An EM-algorithm is developed for estimating the parameters for DMPHs. A number of numerical examples are provided to address some interesting parameter selection issues and to show possible applications of DMPHs.

Low temperature ionic conductor: ionic liquid incorporated within a metal-organic framework.

Ionic liquids (ILs) show promise as safe electrolytes for electrochemical devices. However, the conductivity of ILs decreases markedly at low temperatures because of strong interactions arising between the component ions. Metal-organic frameworks (MOFs) are appropriate microporous host materials that can control the dynamics of ILs via the nanosizing of ILs and tunable interactions of MOFs with the guest ILs. Here, for the first time, we report on the ionic conductivity of an IL incorporated within a MOF. The system studied consisted of EMI-TFSA (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide) and ZIF-8 (Zn(MeIM)2, H(MeIM) = 2-methylimidazole) as the IL and the MOF, respectively. While the ionic conductivity of bulk EMI-TFSA showed a sharp decrease arising from freezing, the EMI-TFSA@ZIF-8 showed no marked decrease because there was no phase transition. The ionic conductivity of EMI-TFSA@ZIF-8 was higher than that of bulk EMI-TFSA below 250 K. This result points towards a novel method by which to design electrolytes for electrochemical devices such as batteries that can operate at low temperatures.

The expansion of 8-year medical training programs in China: a status report

Instituted in major medical programs only within the past decade, the advent of an ‘expanded’ 8-year medical curriculum reflects a major reformation of how physicians are trained in China. Although much remains to be done, including the refinement of associated learning objectives, instructional models, and teaching pedagogies, movement toward a longer, more standardized training framework represents a marked transition for Chinese medical practice. This article highlights the current status and anticipated future of these emerging 8-year medical training programs in modern-day China.

Induction of Ankrd1 in Dilated Cardiomyopathy Correlates with the Heart Failure Progression.

Progression of idiopathic dilated cardiomyopathy (IDCM) is marked with extensive left ventricular remodeling whose clinical manifestations and molecular basis are poorly understood. We aimed to evaluate the clinical potential of titin ligands in monitoring progression of cardiac remodeling associated with end-stage IDCM. Expression patterns of 8 mechanoptotic machinery-associated titin ligands (ANKRD1, ANKRD2, TRIM63, TRIM55, NBR1, MLP, FHL2, and TCAP) were quantitated in endomyocardial biopsies from 25 patients with advanced IDCM. When comparing NYHA disease stages, elevated ANKRD1 expression levels marked transition from NYHA < IV to NYHA IV. ANKRD1 expression levels closely correlated with systolic strain depression and short E wave deceleration time, as determined by echocardiography. On molecular level, myocardial ANKRD1 and serum adiponectin correlated with low BAX/BCL-2 ratios, indicative of antiapoptotic tissue propensity observed during the worsening of heart failure. ANKRD1 is a potential marker for cardiac remodeling and disease progression in IDCM. ANKRD1 expression correlated with reduced cardiac contractility and compliance. The association of ANKRD1 with antiapoptotic response suggests its role as myocyte survival factor during late stage heart disease, warranting further studies on ANKRD1 during end-stage heart failure.

Latitudinal discontinuity in thermal conditions along the nearshore of central-northern Chile.

Over the past decade, evidence of abrupt latitudinal changes in the dynamics, structure and genetic variability of intertidal and subtidal benthic communities along central-northern Chile has been found consistently at 30–32°S. Changes in the advective and thermal environment in nearshore waters have been inferred from ecological patterns, since analyses of in situ physical data have thus far been missing. Here we analyze a unique set of shoreline temperature data, gathered over 4–10 years at 15 sites between 28–35°S, and combine it with satellite-derived winds and sea surface temperatures to investigate the latitudinal transition in nearshore oceanographic conditions suggested by recent ecological studies. Our results show a marked transition in thermal conditions at 30–31°S, superimposed on a broad latitudinal trend, and small-scale structures associated with cape-and-bay topography. The seasonal cycle dominated temperature variability throughout the region, but its relative importance decreased abruptly south of 30–31°S, as variability at synoptic and intra-seasonal scales became more important. The response of shoreline temperatures to meridional wind stress also changed abruptly at the transition, leading to a sharp drop in the occurrence of low-temperature waters at northern sites, and a concurrent decrease in corticated algal biomass. Together, these results suggest a limitation of nitrate availability in nearshore waters north of the transition. The localized alongshore change results from the interaction of latitudinal trends (e.g., wind stress, surface warming, inertial period) with a major headland-bay system (Punta Lengua de Vaca at 30.25°S), which juxtaposes a southern stretch of coast characterized by upwelling with a northern stretch of coast characterized by warm surface waters and stratification. This transition likely generates a number of latitude-dependent controls on ecological processes in the nearshore that can explain species-specific effects, and add strength to the suggestion of an oceanography-driven, major spatial transition in coastal communities at 30–31°S.

Experimental binding energies for the metal complexes [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+) for n in the range 4-20.

A supersonic source of clusters has been used to prepare neutral complexes of methanol in association with an alkaline earth metal atom. From these complexes the following metal-containing dications have been generated through electron ionization: [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+), and for n in the range 4-20, kinetic energy release measurements following the evaporation of a single molecule have been undertaken using a high resolution mass spectrometer. Using finite heat bath theory, these data have been transformed into binding energies for individual methanol molecules attached to each of the three cluster systems. In the larger complexes (n > 6) the results exhibit a consistent trend, whereby the experimental binding energy data for all three metal ions are similar, suggesting that the magnitude of the charge rather than charge density influences the strength of the interaction. From a comparison with data recorded previously for (CH3OH)nH(+) it is found that the 2+ charge on a metal ion has an effect on the binding energy of molecules in complexes containing up to 20 solvent molecules. The results recorded for [Ca(CH3OH)n](2+) show evidence of a very marked transition between n = 6 and 7, which is thought to coincide with the completion of a primary solvation shell and the onset of molecules starting to occupy a second and most probably a third shell.

The ratchet effect: dramatic and sustained changes in health care utilization following admission to hospital with chronic disease.

To describe the previously unexamined association between admissions to hospital with chronic disease and changes in all-cause health service utilization over time. A cohort study examining the population of Western Australia with hospitalizations for chronic disease from 2002 to 2010. A "rolling" clearance period is used to define "cardinal events," that is, a disease-specific diagnosis upon hospital admission, where such an event has not occurred in the previous 2 years. Changes in the rate of cardinal events associated with diagnoses of heart failure, type 2 diabetes, chronic obstructive pulmonary disease, cataract with diabetes, asthma, and dialysis are examined. Health service utilization (defined as inpatient days or emergency department presentations) 6 years preceding and 4 years following such events is presented. Cardinal events make up 40%-60% of all chronic disease admissions. A previously undescribed ratchet effect following cardinal events specifically associated with type 2 diabetes, heart failure, and chronic obstructive pulmonary disease is observed. This involves a 2- to 3-fold increase in inpatient days and emergency department presentations that are sustained for at least 4 years. Cardinal events represent an important reference point to understand the impact of chronic disease on health service utilization. Events that herald such a marked transition in health service demand have not been previously described.

River flow regimes and vegetation dynamics along a river transect

Ecohydrological processes occurring within fluvial landscapes are strongly affected by natural streamflow variability. In this work the patterns of vegetation biomass in two rivers characterized by contrasting flow regimes were investigated by means of a comprehensive stochastic model which explicitly couples catchment-scale hydroclimatic processes, morphologic attributes of the river transect and in-stream bio-ecological features. The hydrologic forcing is characterized by the probability distribution (pdf) of streamflows and stages resulting from stochastic precipitation dynamics, rainfall-runoff transformation and reach scale morphologic attributes. The model proved able to reproduce the observed pdf of river flows and stages, as well as the pattern of exposure/inundation along the river transect in both regimes. Our results suggest that in persistent regimes characterized by reduced streamflow variability, mean vegetation biomass is chiefly controlled by the pattern of groundwater availability along the transect, leading to a marked transition between aquatic and terrestrial environments. Conversely, erratic regimes ensure wider aquatic–terrestrial zones in which optimal elevation ranges for species with different sensitivity to flooding and access to groundwater are separated. Patterns of mean biomass in erratic regimes were found to be more sensitive to changes in the underlying hydroclimatic conditions, notwithstanding the reduced responsiveness of the corresponding flow regimes. The framework developed highlights the important role played by streamflow regimes in shaping riverine environments, and may eventually contribute to identifying the influence of landscape, climate and morphologic features on in-stream ecological dynamics.