bluuebunny/crossref_metadata_2025_split huggingface dataset:
Root heterogeneity along an arctic elevational gradient: the importance of resolution
Authors: Träger Sabrina , Wilson Scott D. 
Published: July 2016

Summary

Spatial heterogeneity affects plant performance and is influenced by plants, but the scale at which fine roots react to or generate spatial heterogeneity has received little attention. Fine roots might be expected to respond to heterogeneity at a scale comparable to their diameter (mm), but studies to date have been conducted at much coarser resolutions (cm – m). Here we quantify root heterogeneity in contrasting habitats with special attention to the influence of resolution.

We measured fine root length heterogeneity at resolutions ranging from 1 to 300 mm2, at four elevations along an arctic alpine gradient from 500 m a.s.l. (forest) to 1100 m (tundra). We calculated the magnitude of heterogeneity as the coefficient of variation of root length, and the scale of heterogeneity using semivariance analysis.

The magnitude of heterogeneity was about twofold greater at fine than coarse resolution. Further, the magnitude of heterogeneity was generally greatest at the highest elevation, suggesting that soil at 1100 m was less evenly occupied by plant roots than soils at lower elevations. The exception to this was at the 1 mm2 resolution, for which the magnitude of heterogeneity did not vary with elevation, possibly because heterogeneity at this scale is related to ecophysiological processes common to all vegetation types.

The scale of root length heterogeneity increased significantly with resolution coarseness, suggesting that roots respond to or generate patchiness at small scales that have not previously been examined. In contrast, the scale of heterogeneity did not vary significantly with elevation and the accompanying turnover in growth form.

Our results suggest that roots in four vegetation types respond to or generate very fine scales of spatial heterogeneity, including scales much smaller than those that have previously been examined. Both the magnitude and scale of heterogeneity varied with sampling resolution, suggesting resolutions as small as a few millimetres are relevant to studies of spatial root interactions and below‐ground processes.
Frequency‐domain waveform modelling and inversion for coupled media using a symmetric impedance matrix
Authors: Shin Jungkyun , Jun Hyunggu , Min Dong‐Joo , Shin Changsoo 
Published: July 2016

ABSTRACTTo simulate the seismic signals that are obtained in a marine environment, a coupled system of both acoustic and elastic wave equations is solved. The acoustic wave equation for the fluid region simulates the pressure field while minimizing the number of degrees of freedom of the impedance matrix, and the elastic wave equation for the solid region simulates several elastic events, such as shear waves and surface waves. Moreover, by combining this coupled approach with the waveform inversion technique, the elastic properties of the earth can be inverted using the pressure data obtained from the acoustic region. However, in contrast to the pure acoustic and elastic cases, the complex impedance matrix for the coupled media does not have a symmetric form because of the boundary (continuity) condition at the interface between the acoustic and elastic elements. In this study, we propose a manipulation scheme that makes the complex impedance matrix for acoustic–elastic coupled media to take a symmetric form. Using the proposed symmetric matrix, forward and backward wavefields are identical to those generated by the conventional approach; thus, we do not lose any accuracy in the waveform inversion results. However, to solve the modified symmetric matrix, LDLT factorization is used instead of LU factorization for a matrix of the same size; this method can mitigate issues related to severe memory insufficiency and long computation times, particularly for large‐scale problems.
Diversity of terrestrial isopods in the northern Tunisian wetlands
Authors: Khemaissia Hajer , Jelassi Raja , Touihri Moez , Souty‐Grosset Catherine , Nasri‐Ammar Karima 
Published: July 2016

AbstractTo evaluate the influence of wetland types on the distribution of terrestrial isopods, species richness, relative abundance and diversity indices were studied in the supralittoral zone of 95 wetlands in the north‐western of Tunisian dorsal, belonging to six types: lagoon, hill reservoir, river, dam, lake and sebkha. We tested the following hypothesis: (i) is isopod diversity influenced by wetland types? (ii) is isopod diversity influenced by bioclimatic zones? and (iii) what are the environmental factors influencing isopod distribution? A total of 3255 individuals belonging to twenty species of terrestrial isopods were captured. Species richness differs significantly between wetland types. A highly significant positive relationship between species richness and both humidity and altitudinal gradient was described. The dendrogram of similarities showed a divergence of the lagoons compared to the remaining wetland types.
Statistical power of replicated helicopter surveys in southern African conservation areas
Authors: Reilly Brian K. , van Hensbergen Hubertus J. , Eiselen Riette J. , Fleming Peter J. S. 
Published: July 2016

AbstractUnderstanding the ecology of large ungulates in southern Africa requires accurate and precise measures of population size. Recovery or exploitation of ungulates in reserves is currently instigated when population size changes exceed 15% per annum, but monitoring is usually undertaken with single counts from helicopters, for which precision and the power to detect change are untested. In essence, power being the strength of a monitoring result in showing change over time. Retrospective power analysis is a useful technique to investigate the variability of single‐count aerial surveys. Using replicated helicopter‐based counts of southern African ungulates and post hoc analysis, we investigated the power of currently used single‐count surveys across five common ungulate species and 11 wildlife reserves. We expected high variability in count data and set α = 0.1 and 0.2 (α being the type I error rate), and asked two questions: ‘How much does power vary in replicated aerial counts of southern African wildlife across reserves and species?’ and ‘Can current single‐count aerial surveys detect population changes in response to management actions or are the statistical errors intractable?’ Single counts were mostly unreliable; only one of 42 had sufficient power to detect meaningful changes in population size or their trends at α = 0.1, and only three had sufficient power at α = 0.2. Power varied widely according to species (e.g. warthog, median power at α = 0.1; 0.12–0.37: blue wildebeest, median power at α = 0.1; 0.23–0.74), and, within species, between replicates and reserves. Our retrospective calculations demonstrated insensitivity and ineffectiveness in most currently applied single counts from helicopters. Consequently, it is impossible to interpret the effects of ungulate conservation actions on many southern African reserves. Retrospective power analyses enables determination of which previous aerial surveys were useful for population assessment and adaptive management, and which should be discarded. We recommend that prospective power analyses are undertaken to determine future helicopter survey sample size and replication requirements, especially in small reserves.
Aspect and slope as determinants of vegetation composition and soil properties in coastal forest backdunes of Eastern Cape, South Africa
Authors: Ruwanza Sheunesu , Shackleton Charlie M. 
Published: July 2016

AbstractCoastal sand dune ecosystems are subjected to many stress and disturbance factors that are particularly high in the foredunes compared to the backdunes. Although a few studies have been conducted on eastern coastline sand dunes of South Africa, none have examined the relationship between aspect and slope on vegetation composition and soil properties of coastal forest backdunes. Vegetation and soil sampling were conducted in 11 transects, each with four plots measuring 10 × 10 m, located on the seaward and landward sides and on middle and lower slopes of backdunes of Bathurst coastal forest. A total of 39 species were identified, of which 23 were trees and shrubs, thirteen were forbs and three were grasses. The data show that both aspect and slope had limited influence on vegetation community assemblage and soil properties, but had significant effects on individual species distribution. There was a grass‐dominated community on the middle slope and a tree‐ and shrub‐ dominated community on the lower slope. These two plant communities act as the required coastal forest ecosystem engineer driving variability in soil properties between the slopes, the most prominent being high soil nutrients and moisture in the lower slopes compared to the middle slopes.
Urethral diverticulectomy with Martius labial fat pad interposition improves symptom resolution and reduces recurrence
Authors: Malde Sachin , Sihra Néha , Naaseri Sahar , Spilotros Marco , Solomon Eskinder , Pakzad Mahreen , Hamid Rizwan , Ockrim Jeremy L. , Greenwell Tamsin J. 
Published: July 2016

ObjectiveTo assess the presenting features and medium‐term symptomatic outcomes in women having excision of urethral diverticulum with Martius labial fat pad (MLFP) interposition.Patients and MethodsWe reviewed our prospective database of all female patients having excision of a symptomatic urethral diverticulum between 2007 and 2015. Data on demographics, presenting symptoms and clinical features were collected, as well as postoperative outcomes.ResultsIn all, 70 women with a mean (range) age of 46.5 (24–77) years underwent excision of urethral diverticulum with MLFP interposition. The commonest presenting symptoms were a urethral mass (69%), urethral pain (61%), and dysuria (57%). Pre‐existing stress urinary incontinence (SUI) was present in 41% (29) of the women. After surgery, at a mean (SD) of 18.9 (16.4) months follow‐up (median 14 months), complete excision of urethral diverticulum was achieved in all the women, with resolution of urethral mass, dysuria and dyspareunia in all, and urethral pain in 81%. Immediately after surgery, 10 (24%) patients reported de novo SUI, which resolved with time and pelvic floor muscle training such that at 12 months only five (12%) reported continued SUI. There was one symptomatic diverticulum recurrence (1.4%).ConclusionsThe commonest presenting symptom of a female urethral diverticulum is urethral pain followed by dysuria and dyspareunia. Surgical excision with MLFP interposition results in complete resolution of symptoms in most women. The incidence of persistent de novo SUI in an expert high‐volume centre is 12%.
Robotic perineal radical prostatectomy and pelvic lymph node dissection using a purpose‐built single‐port robotic platform
Authors: Ramirez Daniel , Maurice Matthew J. , Kaouk Jihad H. 
Published: July 2016

ObjectivesTo describe the features of the novel, purpose‐built da Vinci model SP1098 single‐port robotic platform and to describe a step‐by‐step approach for perineal prostatectomy and pelvic lymph node dissection in a cadaver model.MethodsThree single‐port robotic radical perineal prostatectomies and two pelvic lymph node dissections were performed on three male cadavers to assess the feasibility of the SP1098 da Vinci robotic platform. The steps in the procedure included division of the rectourethralis muscle, splitting of the levator ani muscles bilaterally, opening of Denonvilliers fascia with dissection of the seminal vesicles, apical dissection and urethral division, anterior and lateral dissection with ligation of prostatic pedicles, bilateral pelvic lymph node dissection, and creation of the new vesico‐urethral anastomosis. The main outcomes assessed were operating time per step, total operating time, intra‐operative complications and need for conversion to conventional or open techniques.ResultsNo conversions were required. No intra‐operative complications were seen. The median (range) operating time for performing single‐port robotic radical perineal prostatectomy and pelvic lymph node dissection was 210 (180–240) min.ConclusionsWe have shown the feasibility and efficacy of a novel, purpose‐built robotic system in performing single‐port radical perineal prostatectomy and describe, for the first time, the feasibility of robotic perineal lymph node dissection. This single‐port system will facilitate single‐port applications and allow surgeons to perform major urological operations via a small, single incision while preserving triangulation and optics, and eliminating clashing between instruments. Future clinical studies are needed to support these encouraging outcomes.
Predicting complications in partial nephrectomy for T1a tumours: does approach matter?
Authors: Ramirez Daniel , Maurice Matthew J. , Caputo Peter A. , Nelson Ryan J. , Kara Önder , Malkoç Ercan , Kaouk Jihad H. 
Published: July 2016

ObjectivesTo assess differences in complications after robot‐assisted (RAPN) and open partial nephrectomy (OPN) among experienced surgeons.Patients and MethodsWe identified patients in our institutional review board‐approved, prospectively maintained database who underwent OPN or RAPN for management of unifocal, T1a renal tumours at our institution between January 2011 and August 2015. The primary outcome measure was the rate of 30‐day overall postoperative complications. Baseline patient factors, tumour characteristics and peri‐operative factors, including approach, were evaluated to assess the risk of complications.ResultsPatients who underwent OPN were found to have a higher rate of overall complications (30.3% vs 18.2%; P = 0.038), with wound complications accounting for the majority of these events (11.8% vs 1.8%; P < 0.001). Multivariable logistic regression analysis showed the open approach to be an independent predictor of overall complications (odds ratio 1.58, 95% confidence interval 1.03–2.43; P = 0.035). Major limitations of the study include its retrospective design and potential lack of generalizability.ConclusionsThe open surgical approach predicts a higher rate of overall complications after partial nephrectomy for unifocal, T1a renal tumours. For experienced surgeons, the morbidity associated with nephron‐sparing surgery may be incrementally improved using the robot‐assisted approach.
Oligodendroglial deletion of ESCRT‐I component TSG101 causes spongiform encephalopathy
Authors: Walker Will P. , Oehler Abby , Edinger Aimee L. , Wagner Kay‐Uwe , Gunn Teresa M. 
Published: July 2016

Background InformationVacuolation of the central nervous system (CNS) is observed in patients with transmissible spongiform encephalopathy, HIV‐related encephalopathy and some inherited diseases, but the underlying cellular mechanisms remain poorly understood. Mice lacking the mahogunin ring finger‐1 (MGRN1) E3 ubiquitin ligase develop progressive, widespread spongiform degeneration of the CNS. MGRN1 ubiquitinates and regulates tumour susceptibility gene 101 (TSG101), a central component of the endosomal trafficking machinery. As loss of MGRN1 is predicted to cause partial TSG101 loss‐of‐function, we hypothesised that CNS vacuolation in Mgrn1 null mice may be caused by the accumulation of multi‐cisternal endosome‐like ‘class E’ vacuolar protein sorting (vps) compartments similar to those observed in Tsg101‐depleted cells in culture.ResultsTo test this hypothesis, Tsg101 was deleted from mature oligodendroglia in vivo. This resulted in severe spongiform encephalopathy, histopathologically similar to that observed in Mgrn1 null mutant mice but with a more rapid onset. Vacuoles in the brains of Tsg101‐deleted and Mgrn1 mutant mice labelled with endosomal markers, consistent with an endosomal origin. Vacuoles in the brains of mice inoculated with Rocky Mountain Laboratory (RML) prions did not label with these markers, indicating a different origin, consistent with previously published studies that indicate RML prions have a primary effect on neurons and cause vacuolation in an MGRN1‐independent manner. Oligodendroglial deletion of Rab7, which mediates late endosome‐to‐lysosome trafficking and autophagosome–lysosome fusion, did not cause spongiform change.ConclusionsOur data suggest that the formation of multi‐cisternal ‘class E’ vps endosomal structures in oligodendroglia leads to vacuolation.SignificanceThis work provides the first evidence that disrupting multi‐vesicular body formation in oligodendroglia can cause white matter vacuolation and demyelination. HIV is known to hijack the endosomal sorting machinery, suggesting that HIV infection of the CNS may also act through this pathway to cause encephalopathy.
Activation of inflammatory immune gene cascades by lipopolysaccharide (LPS) in the porcine colonic tissue ex-vivo model
Authors: Bahar B , O'Doherty J V , Vigors S , Sweeney T 
Published: July 2016

Summary
The technique of challenging postmortem tissue explants with inflammation inducer such as lipopolysaccharide (LPS) followed by gene expression analysis is used widely for evaluating the immune-suppressing effect of bioactives. Using porcine colonic tissue as an ex-vivo model of mammalian intestinal gut, this study evaluated the effect of incubation time on the integrity of gene transcripts and activation of inflammatory immune gene cascade by LPS treatment. Post-slaughter colon was removed surgically and explants were incubated for 0, 3, 6 and 12 h and the abundance of mRNA transcripts of a panel of 92 immune genes were evaluated using quantitative polymerase chain reaction (qPCR) arrays. The mRNA transcripts were highly intact after 0 and 3 h of incubation; however, after 6 h the degradation was clearly evident. Following 3 h incubation, 98·8% and 100% mRNA transcripts were detectable in the colonic tissue harvested from weaned and mature pigs, respectively. In the explants of weaned piglets, LPS treatment activated inflammatory signalling pathways [high mobility group B1 (HMGB1), dendritic cell maturation, interleukin (IL)-6, IL-8, IL-17F], while these pathways were inhibited by dexamethasone treatment. Activations of inflammatory genes were also evident in the explants collected from the mature pigs subjected to ex-vivo incubation for 3 h in the absence or presence of LPS. It is concluded that the colonic explant remains physiologically viable and responsive to immunological challenge for up to 3 h ex-vivo.
Seizure‐onset patterns in focal cortical dysplasia and neurodevelopmental tumors: Relationship with surgical prognosis and neuropathologic subtypes
Authors: Lagarde Stanislas , Bonini Francesca , McGonigal Aileen , Chauvel Patrick , Gavaret Martine , Scavarda Didier , Carron Romain , Régis Jean , Aubert Sandrine , Villeneuve Nathalie , Giusiano Bernard , Figarella‐Branger Dominique , Trebuchon Agnès , Bartolomei Fabrice 
Published: July 2016

SummaryObjectivesThe study of intracerebral electroencephalography (EEG) seizure‐onset patterns is crucial to accurately define the epileptogenic zone and guide successful surgical resection. It also raises important pathophysiologic issues concerning mechanisms of seizure generation. Until now, several seizure‐onset patterns have been described using distinct recording methods (subdural, depth electrode), mostly in temporal lobe epilepsies or with heterogeneous neocortical lesions.MethodsWe analyzed data from a cohort of 53 consecutive patients explored by stereoelectroencephalography (SEEG) and with pathologically confirmed malformation of cortical development (MCD; including focal cortical dysplasia [FCD] and neurodevelopmental tumors [NDTs]).ResultsWe identified six seizure‐onset patterns using visual and time‐frequency analysis: low‐voltage fast activity (LVFA); preictal spiking followed by LVFA; burst of polyspikes followed by LVFA; slow wave/DC shift followed by LVFA; theta/alpha sharp waves; and rhythmic spikes/spike‐waves. We found a high prevalence of patterns that included LVFA (83%), indicating nevertheless that LVFA is not a constant characteristic of seizure onset. An association between seizure‐onset patterns and histologic types was found (p = 001). The more prevalent patterns were as follows: (1) in FCD type I LVFA (23.1%) and slow wave/baseline shift followed by LVFA (15.4%); (2) in FCD type II burst of polyspikes followed by LVFA (31%), LVFA (27.6%), and preictal spiking followed by LVFA (27.6%); (3) in NDT, LVFA (54.5%). We found that a seizure‐onset pattern that included LVFA was associated with favorable postsurgical outcome, but the completeness of the EZ resection was the sole independent predictive variable.SignificanceSix different seizure‐onset patterns can be described in FCD and NDT. Better postsurgical outcome is associated with patterns that incorporate LVFA.
Innovating immune tolerance induction for haemophilia
Authors: Batsuli G. , Meeks S. L. , Herzog R. W. , Lacroix‐Desmazes S. 
Published: July 2016

IntroductionHaemophilia A is an X‐linked bleeding disorder characterized by a deficiency of coagulation protein factor VIII (FVIII). A challenging complication of therapeutic FVIII infusions is the formation of neutralizing alloantibodies against the FVIII protein defined as inhibitors. The development of FVIII inhibitors drastically alters the quality of life of the patients and is associated with tremendous increases in morbidity as well as treatment costs.AimCurrent clinical immune tolerance induction protocols to reverse inhibitors are lengthy, costly and not effective in all patients. Prophylactic protocols to prevent inhibitor formation have not yet been developed in the clinical setting. However, there has been ample progress towards this goal in recent years in preclinical studies using animal models of haemophilia.MethodsHere, we review the mechanisms that lead to inhibitor formation against FVIII and two promising new strategies for antigen‐specific tolerance induction.ResultsCD4+ T cells play an important role in the FVIII‐specific B cell response. Immune tolerance can be induced based on transplacental delivery of FVIII domains fused to Fc or on oral delivery of leaf cells from chloroplast transgenic crop plants.ConclusionsRecent literature suggests that prophylactic tolerance induction protocols for FVIII may be feasible in haemophilia A patients.
Impact of enzyme preparation and degree of hydrolysis on peptide profile and nitrogen solubility of sodium caseinate hydrolysates
Authors: Rajarathnam Ebenezer , Nongonierma Alice B. , O'Sullivan Dara , Flynn Cal , FitzGerald Richard J. 
Published: July 2016

SummaryThe solubility of casein ingredients is limited under certain pH conditions. Therefore, sodium caseinate (NaCN) was hydrolysed at laboratory scale with four enzyme preparations (Alcalase, Prolyve, FlavorPro Whey and pepsin) yielding hydrolysates having degree of hydrolysis (DH) values between 0.19 ± 0.11 and 19.25 ± 0.73%. The nitrogen solubility index (NSI) over the pH range 2.0–8.0 was affected by (i) the specificity of the enzyme preparation, (ii) the DH and (iii) the presence of unhydrolysed NaCN within the hydrolysate. The trends observed at laboratory scale (<5 L) were also seen with the semi‐pilot‐scale (300 L) hydrolysates generated with Alcalase and FlavorPro Whey. Removal of unhydrolysed NaCN from the FlavorPro Whey hydrolysate using a 5‐kDa ultrafiltration (UF) membrane increased NSI. This study has highlighted the importance of carefully selecting the proteolytic preparation along with the DH to design casein‐based ingredients with enhanced technofunctional properties.