A survey of
Pinus cembra
(Arolla pine) growing above 2800-m elevation was conducted in an ecoregion of the western Alps, where the highest treeline is at ~ 2650 m. The concepts of treeline and ...species line are discussed based on these field observations. The species line is the biological limit of a species, with inherited nested historical and current processes of high-mountain socio-ecosystems, while the treeline strictly concerns the limit of erect trees. Arolla pines were located and described (height, physiognomy) and their habitats recorded (elevation, slope, aspect). Individuals occurred up to 3200 m on east-facing steep and rocky slopes, with density decreasing exponentially with increasing elevation (halving every 40 m). East-facing habitats benefit from the main atmospheric moisture coming from the east (Italy). Individuals were mostly dwarf-shaped/prostrate (58%) or trees (39%; max height 3.8 m). They usually do not bear female cones, and needles are smaller by half compared to those of pines growing in lower elevation forests. Their morphology indicates harsh growing conditions due to elevation (aridity, frost) and disturbances (wind, snow, rockfall). Habitat preference primarily on grass-free steep rocky slopes and cliffs at high elevation is likely explained by the exclusion of livestock impacts (grazing, trampling). These pines constitute noteworthy “sky island” populations.
Larix decidua
and
Pinus uncinata
were also recorded above the treeline, but with lower maximum elevation and density than
Pinus cembra
. These observations highlight a complex pattern of species treeline in the western Alps, and probably beyond, with relevance to issues in conservation science.
: This article presents a methodology that integrates cumulative plots with probe vehicle data for estimation of travel time statistics (average, quartile) on urban networks. The integration reduces ...relative deviation among the cumulative plots so that the classical analytical procedure of defining the area between the plots as the total travel time can be applied. For quartile estimation, a slicing technique is proposed. The methodology is validated with real data from Lucerne, Switzerland and it is concluded that the travel time estimates from the proposed methodology are statistically equivalent to the observed values.
•Definition of a methodology to detect the cluster phenomenon among RAP particles during the mixing process.•Different factors that affect the phenomenon of clustering are identified.•First approach ...to detect the partial differential aging in bitumen thickness.•The mobilization of RAP binder is negligible.
The present study defines a procedure for gaining a better understanding of the interaction between the aged and the virgin binders and what actually occurs during a mix process. Indeed, the authors propose a methodology to determine and quantify the cluster phenomenon in mixtures containing RAP, defining how the aged binder interacts in the mix. Rheology, in particular the complex modulus, becomes the tool thanks to which it is possible to support the hypothesis of the composition of clusters of RAP particles surrounded by the virgin binder during the new mix production, considering different percentages of RAP. Moreover, the authors aim to establish the basis for the hypothesis of the existence of a partial differential aging: the RAP binder on the external surface (i.e. the crust around the aggregate) is more exposed to external factors and oxidation and is over-aged with respect to the binder under the crust that is more protected and less oxidated.
Oxygen intercalation/deintercalation in Pr2NiO4+δ and Nd2NiO4+δ was followed by in situ neutron powder diffraction during electrochemical oxidation/reduction, in a dedicated reaction cell at room ...temperature. For both systems three phases, all showing the same line width, were identified. The starting phases Pr2NiO4.23 and Nd2NiO4.24, considered with an average orthorhombic Fmmm symmetry, although both show a slight monoclinic distortion, get reduced in a two-phase reaction step to tetragonal intermediate phases with 0.07 ≤ δ ≤ 0.10 and P42/ncm space group, which on further reduction transform, again in a two-phase reaction step, toward the respective stoichiometric (Pr/Nd)2NiO4.0 phases, with Bmab space group. Electrochemical oxidation does, however, not proceed fully reversibly for both cases: while the reoxidation of Nd2NiO4+δ is limited to the tetragonal intermediate phase with δ = 0.10, the homologous Pr2NiO4+δ can be reoxidized up to δ = 0.17, showing orthorhombic symmetry. For the intermediate tetragonal phase, we were able to establish for Pr2NiO4.09 a complex anharmonic displacement behavior of the apical oxygen atoms, as analyzed by single-crystal neutron diffraction and maximum entropy analysis, in agreement with a low-T diffusion pathway for oxygen ions, activated by lattice dynamics.
Microsatellites (or SSRs: simple sequence repeats) are among the most frequently used DNA markers in many areas of research. The use of microsatellite markers is limited by the difficulties involved ...in their de novo isolation from species for which no genomic resources are available. We describe here a high‐throughput method for isolating microsatellite markers based on coupling multiplex microsatellite enrichment and next‐generation sequencing on 454 GS‐FLX Titanium platforms. The procedure was calibrated on a model species (Apis mellifera) and validated on 13 other species from various taxonomic groups (animals, plants and fungi), including taxa for which severe difficulties were previously encountered using traditional methods. We obtained from 11 497 to 34 483 sequences depending on the species and the number of detected microsatellite loci ranged from 199 to 5791. We thus demonstrated that this procedure can be readily and successfully applied to a large variety of taxonomic groups, at much lower cost than would have been possible with traditional protocols. This method is expected to speed up the acquisition of high‐quality genetic markers for nonmodel organisms.
Fourier Transform Infrared (FTIR) spectroscopy and powder neutron diffraction (PND) were performed in human subchondral bone covered (C+) or not covered by cartilage (C−) to study hydroxyapatite. ...With FTIR, the carbonation rate was 30% with identical spectra in C+ and C−. With PND, the width of the diffraction peak (hkl = 002) highlighted the anisotropy of nanocrystals (with needle and/or platelet-like shape) along the c-axis with average length of 50 nm and thickness of 10 nm and with no difference between C+ and C−.
Des expérimentations par spectroscopie infrarouge à transformée de Fourier (FTIR) et par diffraction neutronique sur poudres (PND) ont été réalisées sur de l’os sous-chondral humain recouvert (C+) ou non recouvert par le cartilage (C) pour étudier l’hydroxyapatite (HAP).
En FTIR, le taux de carbonatation est de 30% avec des spectres identiques pour C+ et C−. Avec la PND, la largeur du pic de diffraction (hkl = 002) a mis en évidence l'anisotropie des nanocristaux (en forme aiguille et/ou de plaquettes) le long de l'axe c, avec une longueur moyenne de 50 nm et une épaisseur de 10 nm, sans différence entre C+ et C−.
Kidney stones made of whewellite, i.e. calcium oxalate monohydrate, exhibit various morphological aspects. The crystalline structure of whewellite at the atomic scale was revisited through a ...single‐crystal neutron study at room temperature using a four‐circle automated diffractometer. The possible relationships between the various morphological types of whewellite stones and their structural characteristics were examined at the mesoscopic scale by the use of scanning electron microscopy and at the nanometric scale by powder neutron diffraction. All types of whewellite stones displayed a similar structure at the nanometric scale. However, significant differences were found at the mesoscopic scale. In particular, the crystallites in kidney stones resulting from a genetic hyperoxaluria exhibited a peculiar structure. There was a close relationship between stone morphology and crystallite organization at the mesoscopic level and the effectiveness of extracorporeal shockwave lithotripsy.
Genomic alterations play a crucial role in the development and progression of diffuse large B-cell lymphomas (DLBCLs). We determined gene copy number alterations (GCNAs) of TP53, CDKN2A, CDKN1B, ...BCL2, MYC, REL, and RB1 with a single polymerase chain reaction (PCR) assay (quantitative multiplex PCR of short fragments QMPSF) in a cohort of 114 patients with DLBCL to assess their prognostic value and relationship with the gene expression profile. Losses of TP53 and CDKN2A, observed in 8% and 35% of patients, respectively, were significantly associated with a shorter survival after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) treatment, independently of the International Prognostic Index and of the cell of origin. Analysis of the 9p21 genomic region indicated that transcripts encoding p14ARF and p16INK4A were both disrupted in most patients with CDKN2A deletion. These patients predominantly had an activated B-cell profile and showed a specific gene expression signature, characterized by dysregulation of the RB/E2F pathway, activation of cellular metabolism, and decreased immune and inflammatory responses. These features may constitute the molecular basis sustaining the unfavorable outcome and chemoresistance of this DLBCL subgroup. Detection of TP53 and CDKN2A loss by QMPSF is a powerful tool that could be used for patient stratification in future clinical trials.
Objective Bacterial imprints are always observed on highly carbonated apatite kidney stones but not struvite kidney stones. Struvite and carbonated apatite stones with a high CO32– /PO43– rate are ...believed to develop from infections, but their structural differences at the mesoscopic scale lack explanation. Methods We investigated 17 urinary calculi composed mainly of struvite or carbonated apatite by Fourier transform infrared, scanning electron microscopy, and powder neutron diffraction techniques. Results Carbonated apatite but not struvite stones showed bacterial imprints. If the same stone contained both carbonated apatite and struvite components, bacterial imprints were observed on the carbonated apatite but not the struvite part. Moreover, neutron powder diffraction experiments revealed the crystal size of struvite stones were larger than that of carbonated apatite stones (250 ± 50 vs 50 nm). Conclusion Bacterial imprints may appear more easily on kidney stones with small nanocrystals, such as carbonated apatite than with large nanocrystals, such as struvite. This approach may help identify bacteria contributing to stone formation, perhaps with negative results of urine culture.
With an incidence of 1:7000 births, cystinuria, the most frequent cause of stone formation among genetic diseases, represents a major medical problem. Twenty‐five cystine stones randomly selected ...from cystinuric patients were investigated. From a crystallographic point of view, cystine stones are composed of micrometre size crystallites, which are made up of an aggregation of nanocrystals. Through scanning electron microscopy, the morphology and size of the crystallites have been described, while the size of the nanocrystals was investigated by means of powder neutron diffraction. Powder neutron diffraction analysis and/or scanning electron microscopy examination of cystine stones provide evidence that usual alkalinization by sodium bicarbonate associated with high diuresis significantly reduces the size of both nanocrystals and crystallites, while for other treatments, including alkalinizing drugs and thiol derivatives, the data suggest mainly changes in the topology of crystallites. Alkalinization with sodium bicarbonate affects cystine kidney stones at the mesoscopic and nanoscopic scales, while other medical treatments only alter their surface. Such an approach may help to assess the interaction between drugs and cystine stones in cystinuric patients.
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