bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climate change‐driven extinctions of tree species affect forest functioning more than random extinctions
Authors: García‐Valdés Raúl , Bugmann Harald , Morin Xavier 
Published: April 2018

AbstractAimClimate change affects forest functioning not only through direct physiological effects such as modifying photosynthesis and growing season lengths, but also through indirect effects on community composition related to species extinctions and colonizations. Such indirect effects remain poorly explored in comparison with the direct ones. Biodiversity–ecosystem functioning (BEF) studies commonly examine the effects of species loss by eliminating species randomly. However, species extinctions caused by climate change will depend on the species’ vulnerability to the new environmental conditions, thus occurring in a specific, non‐random order. Here, we evaluated whether successive tree species extinctions, according to their vulnerability to climate change, impact forest functions differently than random species losses.LocationEleven temperate forests across a gradient of climatic conditions in central Europe.MethodsWe simulated tree community dynamics with a forest succession model to study the impact of species loss on the communities’ aboveground biomass, productivity and temporal stability. Tree species were removed from the local pool (1) randomly, and according to (2) their inability to be recruited under a warmer climate or (3) their increased mortality under drier conditions.ResultsResults showed that non‐random species loss (i.e., based on their vulnerability to warmer or drier conditions) changed forest functioning at a different rate, and sometimes direction, than random species loss. Furthermore, directed extinctions, unlike random, triggered tipping points along the species loss process where forest functions were strongly impacted. These tipping points occurred after fewer extinctions in forests located in the coldest areas, where ecosystem functioning relies on fewer species.Main conclusionsWe showed that the extinction of species in a deterministic and mechanistically motivated order, in this case the species vulnerability to climate change, strengthens the selection effect of diversity on ecosystem functioning. BEF studies exploring the impact of species loss on ecosystem functioning using random extinctions thus possibly underestimate the potential effect of biodiversity loss when driven by a directional force, such as climate change.
Effects of El Niño Southern Oscillation on avian breeding phenology
Authors: Englert Duursma Daisy , Gallagher Rachael V. , Griffith Simon C. 
Published: April 2018

AbstractAimClimate oscillations are known to influence the reproductive phenology of birds. Here, we quantify the effects of cyclic climatic variation, specifically El Niño Southern Oscillation (ENSO), on birds that breed opportunistically. We aim to show how inter‐decadal climate fluctuations influence opportunistic breeding. This knowledge is essential for tracking the phenological responses of birds to climate change.LocationTemperate and arid Australia.MethodsWe assessed variation in egg‐laying (start, peak, conclusion, length) during the three phases of ENSO (El Niño, La Niña and Neutral) for 64 temperate and 15 arid region species using ~80,000 observations. Linear mixed‐effect models and analysis of variance were used to (1) determine if, on average within each region, egg‐laying dates differed significantly among species between Neutral‐El Niño and Neutral‐La Niña phases, and (2) assess how La Niña and El Niño episodes influence egg‐laying in birds which breed early in the year.ResultsDuring La Niña phases, which are characterized by mild/wet conditions, most bird species in the temperate and arid regions exhibited longer egg‐laying periods relative to Neutral phases. However, there was substantial variation across species. This effect was strongly seasonal; species breeding in spring experienced the greatest increases in egg‐laying periods during La Niña. Further, we found only small differences in peak egg‐laying dates during Neutral and La Niña in the arid region; suggesting that hot temperatures may constrain breeding regardless of rainfall. The effects of El Niño on breeding phenology were not consistent in the temperate and arid regions and may be confounded by highly mobile species opportunistically moving and breeding with localized rainfall during dry periods.Main conclusionsIn both arid and temperate regions, increased rainfall associated with La Niña phases positively influences avian breeding, and likely recruitment. However, dry El Niño phases may not have the dramatic impacts on breeding phenology that are commonly assumed.
Differentiating arterial ischaemic stroke from migraine in the paediatric emergency department
Authors: Mackay Mark T , Lee Michelle , Yock‐Corrales Adriana , Churilov Leonid , Donnan Geoffrey A , Monagle Paul , Babl Franz E 
Published: April 2018

AimTo estimate the strengths of association between clinical features and migraine or arterial ischaemic stroke (AIS) in children presenting to the emergency department.MethodEighty‐four children with migraine, prospectively recruited from 2009 to 2010, were compared with 55 children with AIS, prospectively/retrospectively recruited from 2003 to 2010. Odds ratios were calculated via logistic regression to measure associations between clinical features and process‐of‐care factors, and migraine and AIS.ResultsMedian age was 13 years 5 months (interquartile range 12y 11mo–13y 10mo) for migraine and 5 years (interquartile range 3y 7mo–8y) for patients with AIS. All cases of AIS and 30% of migraine cases underwent neuroimaging. Over 40% of children with migraine had vomiting, numbness, or visual disturbance; other symptoms were uncommon. Fifty‐five per cent had no signs on physician assessment. Weakness or speech disturbance were common in patients with AIS. Significant clinical features associated with increased odds of AIS included sudden symptom onset, weakness, seizures, speech disturbance, and ataxia, and signs of face, arm, or leg weakness, inability to walk, dysarthria, dysphasia, and altered consciousness (p<0.05). Significant features associated with decreased odds of AIS included older age, vomiting, visual, sensory, other symptoms, and absent focal signs on assessment (p<0.05).InterpretationPresenting features can discriminate childhood AIS from migraine. These differences inform decisions about urgency and type of neuroimaging in children presenting to the emergency department with brain attack symptoms.What the paper adds

Weakness, seizures, ataxia, speech, or walking difficulties are more frequent in arterial ischaemic stroke (AIS).

Vomiting, visual, or sensory disturbance and absent focal signs are more frequent in migraine.

Identifying features of AIS and migraine guides neuroimaging in children with brain attack symptoms.
Pharmacokinetic and pharmacodynamic profile of the sodium‐glucose co‐transporter‐2 inhibitor empagliflozin in young people with Type 2 diabetes: a randomized trial
Authors: Laffel L. M. B. , Tamborlane W. V. , Yver A. , Simons G. , Wu J. , Nock V. , Hobson D. , Hughan K. S. , Kaspers S. , Marquard J. 
Published: April 2018

AbstractAimsTo assess the pharmacokinetic and pharmacodynamic profile of a single dose of empagliflozin in young people with Type 2 diabetes to identify the appropriate doses for further paediatric development.MethodsWe conducted a single‐dose, open‐label, randomized, parallel‐group study with empagliflozin 5 mg, 10 mg and 25 mg in young people with Type 2 diabetes aged 10–17 years.ResultsOf 39 participants screened, 27 were randomized and completed the study; their mean (± sd) age was 14.1±2.0 years and body weight was 96.7±23.5 kg. Compared with similar studies in adults with Type 2 diabetes, the maximum observed plasma concentrations were slightly lower with the 10‐mg and 25‐mg doses, and the area under the plasma concentration–time curve was slightly lower with the 10‐mg but slightly higher with the 25‐mg dose. The adjusted mean increases in urinary glucose excretion were 53 g/24 h (95% CI 32,74), 73 g/24 h (95% CI 52,94) and 87 g/24 h (95% CI 68,107), and the adjusted mean decreases in fasting plasma glucose were 0.9 mmol/l (95% CI –1.6,–0.1), 0.9 mmol/l (95% CI –1.7,–0.2) and 1.1 mmol/l (95% CI –1.8,–0.5) for the 5‐ 10‐ and 25‐mg doses, respectively. There were no serious adverse events and one investigator‐reported drug‐related event (dehydration).ConclusionsAfter a single oral dose of empagliflozin, adults and young people with Type 2 diabetes had similar exposure–response relationships after adjusting for significant covariates. These data support testing 10‐mg and/or 25‐mg doses of empagliflozin in an upcoming paediatric phase III Type 2 diabetes trial.(ClinicalTrials.gov registration no.: NCT02121483).
Is glucagon‐like peptide‐1 fully protected by the dipeptidyl peptidase 4 inhibitor sitagliptin when administered to patients with type 2 diabetes?
Authors: Andersen Emilie S. , Lund Asger , Bagger Jonatan I. , Andreasen Camilla , Grøndahl Magnus F. , Deacon Carolyn F. , Hartmann Bolette , Holst Jens J. , Knop Filip K. , Vilsbøll Tina 
Published: April 2018

AimTo evaluate the relationship between plasma dipeptidyl‐peptidase 4 (DPP‐4) activity and its protection of glucagon‐like peptide‐1 (GLP‐1) using the DPP‐4 inhibitor sitagliptin.MethodsOn four separate days, patients with type 2 diabetes (T2D) (n = 8; age: 59.9 ±10.8 [mean ±SD] years; body mass index [BMI]: 28.8 ±4.6 kg/m2; glycated haemoglobin A1c [HbA1c]: 43.1 ±0.5 mmol/mol [6.6% ±1.7%]) received a 380‐minute continuous intravenous infusion of GLP‐1 (1.0 pmol × kg bodyweight−1 × minutes−1) and a double‐blind, single‐dose oral administration of sitagliptin in doses of 0 (placebo), 25, 100 and 200 mg.ResultsPlasma DPP‐4 activity decreased compared to baseline (placebo) with increasing doses of sitagliptin (P < .01), reaching a maximal inhibition with the 100 mg dose. Levels of intact GLP‐1 increased with increasing doses of sitagliptin from placebo to 100 mg (area under curve [AUC] 7.2 [95%, CI; 12.1, 16.4] [placebo], 10.7 [16.1, 21.4] [25 mg], 11.7 [17.8, 23.6] [100 mg] nmol/L × 360 minutes [P < .01]), but no further increase in intact GLP‐1 levels was observed with 200 mg of sitagliptin (11.5 [17.6, 23.4] nmol/L × 360 minutes) (P = .80).ConclusionOur findings suggest that the sitagliptin dose of 100 mg is sufficient to inhibit both plasma and membrane‐bound DPP‐4 activity, presumably also leading to complete protection of endogenous GLP‐1 in patients with T2D.
Political business cycles and construction licensing
Authors: Imami Drini , Uberti Luca J. , Lami Endrit , Zhllima Edvin 
Published: April 2018

AbstractWe analyze the effects of opportunistic and partisan politics on the licensing of construction activities, which in turn determines the level of housing supply. In line with Political Business Cycle theory, we hypothesize that the municipal incumbent may manipulate the supply of construction permits before (general and local) elections in order to boost economic activity and voter satisfaction, or to accommodate special‐interest groups. Our findings, based on time‐series data from post‐socialist Tirana (Albania), are consistent with opportunistic and partisan incentives’ creating cycle effects in the licensing of construction permits. However, we find that the direction of opportunistic election cycles depends critically on the interaction between the municipal incumbent and the central‐level government. Our paper raises important questions about the effects of transition politics on spatial development in post‐socialist cities.
The tethered flight technique as a tool for studying life‐history strategies associated with migration in insects
Authors: Minter Melissa , Pearson Aislinn , Lim Ka S. , Wilson Kenneth , Chapman Jason W. , Jones Christopher M. 
Published: April 2018

1. Every year billions of insects engage in long‐distance, seasonal mass migrations which have major consequences for agriculture, ecosystem services and insect‐vectored diseases. Tracking this movement in the field is difficult, with mass migrations often occurring at high altitudes and over large spatial scales.2. As such, tethered flight provides a valuable tool for studying the flight behaviour of insects, giving insights into flight propensity (e.g. distance, duration and velocity) and orientation under controlled laboratory settings. By experimentally manipulating a variety of environmental and physiological traits, numerous studies have used this technology to study the flight behaviour of migratory insects ranging in size from aphids to butterflies. Advances in functional genomics promise to extend this to the identification of genetic factors associated with flight. Tethered flight techniques have been used to study migratory flight characteristics in insects for more than 50 years, but have never been reviewed.3. This study summarises the key findings of this technology, which has been employed in studies of species from six Orders. By providing detailed descriptions of the tethered flight systems, the present study also aims to further the understanding of how tethered flight studies support field observations, the situations under which the technology is useful and how it might be used in future studies.4. The aim is to contextualise the available tethered flight studies within the broader knowledge of insect migration and to describe the significant contribution these systems have made to the literature.
How do invasive species affect native species? Experimental evidence from a carrion blowfly (Diptera: Calliphoridae) system
Authors: Carmo Rodrigo F. R. , Vasconcelos Simão D. , Brundage Adrienne L. , Tomberlin Jeffery K. 
Published: April 2018

1. The necrobiome is a unique microcosm in which various organisms interact and compete for access to an ephemeral resource, such as carrion, that ultimately determines the structure and composition of these assemblages.2. Blowfly species exhibit different competitive abilities which, when associated with other types of behaviour, such as predation or cannibalism, influence coexistence. Knowledge of the effects of competition between native and invasive species on development and survival is essential to understanding the dynamics of insect communities and to assess biological invasions.3. Laboratory experiments were performed to evaluate the effect of interspecific competition on the bionomics and survival of a native (Cochliomyia macellaria) and an invasive (Chrysomya rufifacies) blowfly species at different population densities.4. The deleterious effect of competition on the larval parameters of C. macellaria increased proportionally with increases in the larval density of C. rufifacies. When exposed to increased densities of C. rufifacies, larvae of C. macellaria accelerated their development and, as a trade‐off for this strategy, surviving adults were smaller and had reduced wing size, which were likely to reduce dispersal and reproductive capacity.5. Larval competition – both as species‐dependent and density‐dependent phenomena – influences morphological and biological traits of surviving individuals. The impact of the invasive species has consequences at the population level, such as displacement or local population depletion of native species, a phenomenon likely to occur in other systems involving insects and ephemeral resources.
Diagnostic outcomes for genetic testing of 70 genes in 8565 patients with epilepsy and neurodevelopmental disorders
Authors: Lindy Amanda S. , Stosser Mary Beth , Butler Elizabeth , Downtain‐Pickersgill Courtney , Shanmugham Anita , Retterer Kyle , Brandt Tracy , Richard Gabriele , McKnight Dianalee A. 
Published: April 2018

SummaryObjectiveWe evaluated >8500 consecutive, unselected patients with epilepsy and neurodevelopmental disorders who underwent multigene panel testing to determine the average age at molecular diagnosis and diagnostic yield of 70 genes.MethodsWe reviewed molecular test results for 70 genes known to cause epilepsy and neurodevelopmental disorders using next generation sequencing (NGS) and exon‐level array comparative genomic hybridization (aCGH). A positive result was defined as the presence of 1 or 2 pathogenic or likely pathogenic (P/LP) variants in a single gene, depending on the mode of inheritance of the associated disorder.ResultsOverall, 22 genes were found to have a high yield of positive findings by genetic testing, with SCN1A and KCNQ2 accounting for the greatest number of positive findings. In contrast, there were no positive findings in 16 genes. Most of the P/LP variants were sequence changes identified by NGS (90.9%), whereas ~9% were gross deletions or duplications detected by exon‐level aCGH. The mean age of molecular diagnosis for the cohort was 5 years, 8 months (ranging from 1 week to 47 years). Recurrent P/LP variants were observed in 14 distinct genes, most commonly in MECP2, KCNQ2, SCN1A, SCN2A, STXBP1, and PRRT2. Parental testing was performed in >30% of positive cases. All variants identified in CDKL5, STXBP1, SCN8A, GABRA1, and FOXG1 were de novo, whereas 85.7% of variants in PRRT2 were inherited.SignificanceUsing a combined approach of NGS and exon‐level aCGH, testing identified a genetic etiology in 15.4% of patients in this cohort and revealed the age at molecular diagnosis for patients. Our study highlights both high‐ and low‐yield genes associated with epilepsy and neurodevelopmental disorders, indicating which genes may be considered for molecular diagnostic testing.
The development of in vitro embryo production in the horse
Authors: Morris L. H. A. 
Published: April 2018

SummaryThe development of techniques to produce equine embryos in vitro is reviewed with specific reference to intracytoplasmic sperm injection (ICSI). Unexplored 50 years ago, this technology has progressed rapidly in the last 20 years to become a commercial reality for the equine breeding industry. Improvements in our understanding of oocyte and embryo competence in the horse have been key factors in overcoming some of the initial problems associated with ICSI. It is now possible to obtain high nuclear maturation and cleavage rates in vitro and the most limiting factor, presently, is the low rate of development to the blastocyst stage. However, in spite of this, once obtained, these in vitro‐derived blastocysts can result in pregnancy rates in excess of 60% following transfer.
A study of the environmental survival of Streptococcus equi subspecies equi
Authors: Durham A. E. , Hall Y. S. , Kulp L. , Underwood C. 
Published: April 2018

SummaryBackgroundStreptococcus equi represents a common hazard to equids worldwide. Environmental contamination with bacteria shed from an infected horse may represent a significant source of contagion and further knowledge of ex vivo bacterial survival under different conditions is important for disinfection and isolation protocols.ObjectivesTo determine the potential duration of survival and vigour of growth of S. equi inoculated onto surfaces relevant to equine veterinary practice and stabling in summer and winter.Study designRepeat sampling of environmental inocula of S. equi.MethodsCultures of S. equi were inoculated onto wood, a shoe sole, cotton overalls, inside a nasogastric tube, inside a dental rasp, in a wet plastic bucket and onto a fence post both in the summer and winter seasons. Frequent resampling and culture from the inoculated sites was conducted until no viable bacteria were found. Bacterial viability was determined by both duration (time to first negative culture) and vigour of growth (growth score over the first 3 days of culture) and compared between inoculated sites and times of year.ResultsBacterial viability was enhanced by a wet local environment and by the winter season. Survival tended to be short in the summer (up to 9 days in wet sites and up to 2 days in dry sites) but much longer in the winter (up to 34 days in wet sites and up to 13 days in dry sites). Vigour of bacterial growth was also greater in the winter than in the summer as judged by 3‐day‐growth scores.Main limitationsDirect comparison with the variable size and nature of naturally shed infectious material is difficult.ConclusionsVeterinarians and personnel handling horses should be aware that S. equi may survive in an equine environment for longer than previously found, especially when protected by wet and cold conditions.
Anatomy of equine incisors: Pulp horns and subocclusal dentine thickness
Authors: Englisch L. M. , Rott P. , Lüpke M. , Seifert H. , Staszyk C. 
Published: April 2018

SummaryBackgroundEquine incisors are often reduced in height during corrective dental procedures. Increased knowledge of subocclusal dentine thickness and pulp morphology may help prevent iatrogenic pulpar exposure. Although such data exist for equine cheek teeth, there are currently no reliable data for incisors.ObjectivesTo measure the distances between pulp cavities and the occlusal as well as the labial surfaces of equine incisors and to test if these distances change with age. Furthermore, pulp morphology with regard to number and orientation of pulp horns was investigated.Study designObservational study using cadaver material and high‐resolution computed tomography.MethodsUpper and lower incisor arcades were removed from heads of 13 horses and scanned with high‐resolution computed tomography. 3D Models were reconstructed and configuration as well as number of the pulp horns was evaluated. Anatomical marker points were set to measure distances between the pulp horn tips and the labial and occlusal surfaces.ResultsSubocclusal dentine thickness ranged between 1.5 and 11.7 mm in upper and 0.7 and 6.7 mm in lower incisors. It decreased with tooth age. Distance to labial aspect ranged between 3.5 and 9.0 mm in upper and 3.8 and 8.1 mm in lower incisors and increased with tooth age.Main limitationsDetails of horse management, feeding and previous dental care were not available. Therefore, it remains unknown how these factors influenced the results.ConclusionsAlthough mean subocclusal dentine thickness of greater than 4.1 mm was found, equine incisors occasionally have less than 1 mm of thickness with potential for iatrogenic pulpar exposure during incisor reduction. Therefore, great care should be exercised by any practitioner during incisor reduction.