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11.
1. We examined species–environment relationships and community concordance between aquatic bryophytes and insects in boreal springs. We sampled bryophytes (Marchantiophyta and Bryophyta), benthic macroinvertebrates and environmental variables in 138 springs in Finland, spanning a latitudinal gradient of 1000 km. Macroinvertebrates were subdivided into two groups: Ephemeroptera, Plecoptera, Trichoptera and Coleoptera (EPTC taxa) and chironomid midges (Diptera; Chironomidae). Our aim was to test whether EPTC taxa could be used as surrogates in biodiversity surveys and bioassessment for the two less-well known organism groups, chironomids and bryophytes.
2. Bryophyte assemblages were clearly differentiated along gradients in thermal conditions and water chemistry (pH, conductivity). Chironomids and EPTC were also differentiated in relation to thermal conditions and, to a lesser extent, physical habitat variables, but were only weakly associated to spring water chemistry. Chironomid and EPTC assemblages were more concordant with each other than with bryophytes, but all concordances were relatively weak.
3. Our results suggest that even if the overall compositional patterns of the three taxonomic groups were significantly concordant, the relative importance of environmental drivers underlying their community compositions differed strongly. The results thus imply that spring bryophytes and insects are relatively poor surrogates for each other. The proportion of spring specialists was highest in bryophytes, promoting their primacy for spring bioassessment and biodiversity conservation. We suggest that adequate variation in water chemistry be assured to protect spring bryophyte biodiversity, whereas preserving the physical variation of springs is more important for macroinvertebrates.  相似文献   
12.

Background

Mesenchymal stromal cells (MSCs) are a promising candidate for treatment of inflammatory disorders, but their efficacy in human inflammatory bowel diseases (IBDs) has been inconsistent. Comparing the results from various pre-clinical and clinical IBD studies is also challenging due to a large variation in study designs.

Methods

In this comparative pre-clinical study, we compared two administration routes and investigated the safety and feasibility of both fresh and cryopreserved platelet-lysate–expanded human bone marrow–derived MSCs without additional licensing in a dextran sodium sulfate (DSS) colitis mouse model both in the acute and regenerative phases of colitis. Body weight, macroscopic score for inflammation and colonic interleukin (IL)-1β and tumor necrosis factor (TNF)α concentrations were determined in both phases of colitis. Additionally, histopathology was assessed and Il-1β and Agtr1a messenger RNA (mRNA) levels and angiotensin-converting enzyme (ACE) protein levels were measured in the colon in the regenerative phase of colitis.

Results

Intravenously administered MSCs exhibited modest anti-inflammatory capacity in the acute phase of colitis by reducing IL-1β protein levels in the inflamed colon. There were no clear improvements in mice treated with fresh or cryopreserved unlicensed MSCs according to weight monitoring results, histopathology and macroscopic score results. Pro-inflammatory ACE protein expression and shedding were reduced by cryopreserved MSCs in the colon.

Conclusions

In conclusion, we observed a good safety profile for bone marrow–derived platelet lysate–expanded MSCs in a mouse pre-clinical colitis model, but the therapeutic effect of MSCs prepared without additional licensing (i.e. such as MSCs are administered in graft-versus-host disease) was modest in the chosen in vivo model system and limited to biochemical improvements in cytokines without a clear benefit in histopathology or body weight development.  相似文献   
13.
Despite being popular among amateur and professional lepidopterologists and posing great opportunities for evolutionary research, the phylogenetic relationships of tiger moths (Erebidae: Arctiinae) are not well resolved. Here we provide the first phylogenetic hypothesis for the subtribe Arctiina with the basic aim of clarifying the phylogenetic position of the Wood Tiger Moth Parasemia plantaginis Hübner, a model species in evolutionary ecology. We sampled 89 species in 52 genera within Arctiina s.l., 11 species of Callimorphina and two outgroup species. We sequenced up to seven nuclear genes (CAD, GAPDH, IDH, MDH, Ef1α, RpS5, Wingless) and one mitochondrial gene (COI) including the barcode region (a total of 5915 bp). Both maximum likelihood and Bayesian inference resulted in a well‐resolved phylogenetic hypothesis, consisting of four clades within Arctiina s.s. and a clade comprising spilosomine species in addition to Callimorphina and outgroups. Based on our results, we present a new classification, where we consider the Diacrisia clade, Chelis clade, Apantesis clade, Micrarctia Seitz and Arctia clade as valid genera within Arctiina s.s., whereas Rhyparia Hübner syn.n. and Rhyparioides Butler syn.n. are synonymized with Diacrisia Hübner; Neoarctia Neumoegen & Dyar syn.n. , Tancrea Püngeler syn.n. , Hyperborea Grum‐Grshimailo syn.n. , Palearctia Ferguson syn.n. , Holoarctia Ferguson syn.n. , Sibirarctia Dubatolov syn.n. and Centrarctia Dubatolov syn.n. are synonymized with Chelis Rambur; Grammia Rambur syn.n. , Orodemnias Wallengren syn.n. , Mimarctia Neumoegen & Dyar syn.n. , Notarctia Smith syn.n. and Holarctia Smith syn.n. are synonymized with Apantesis Walker; and Epicallia Hübner syn.n. , Eucharia Hübner syn.n. , Hyphoraia Hübner syn.n. , Parasemia Hübner syn.n. , Pericallia Hübner syn.n. , Nemeophila Stephens syn.n. , Ammobiota Wallengren syn.n. , Platarctia Packard syn.n. , Chionophila Guenée syn.n. , Eupsychoma Grote syn.n. , Gonerda Moore syn.n. , Platyprepia Dyar syn.n. , Preparctia Hampson syn.n. , Oroncus Seitz syn.n. , Acerbia Sotavalta syn.n. , Pararctia Sotavalta syn.n. , Borearctia Dubatolov syn.n. , Sinoarctia Dubatolov syn.n. and Atlantarctia Dubatolov syn.n. are synonymized with Arctia Schrank, leading to 33 new genus‐level synonymies. Our focal species Arctia plantaginis comb.n. is placed as sister to Arctia festiva comb.n. , another widespread aposematic species showing wing pattern variation. Our molecular hypothesis can be used as a basis when adding more species to the tree and tackling interesting evolutionary questions, such as the evolution of warning signalling and mimicry in tiger moths.  相似文献   
14.
Inflorescence size was investigated in a range of apple treecultivars. Each inflorescence size was quantified by the numberof foliage leaves and flowers. A first analysis was carriedout usingdependence stereogramsand standardized non-parametriccorrelation coefficients, based on Kendall 's  相似文献   
15.
16.
Abstract. The genus Lypusa Zeller, 1852 has been assigned to Tineoidea (Lepidoptera) with varying family positions. The systematic affinities of this genus, currently placed in its own family Lypusidae, were studied using extensive data derived from larval, pupal and adult morphology and certain behavioural traits. In total, 193 characters were considered. On the basis of the results of a parsimony analysis, Lypusa is transferred to the superfamily Gelechioidea, in a monophyletic, exclusively Palaearctic assemblage with the genera Amphisbatis and Pseudatemelia. Several phylogenetically relevant characters support this position, including similarly constructed larval cases, densely porose larval head, and a modification of the pupal abdominal segment 8. The composition of the family Amphisbatidae is discussed and it is proposed that it be delimited as comprising solely the Palaearctic genera Pseudatemelia, Amphisbatis and Lypusa. A detailed diagnosis of the genus Lypusa is given.  相似文献   
17.
We introduce a method to transform wing venation data to a numerical form so that the venation pattern can be analysed and compared regardless of wing size and displacement of the pattern. We use the method for assessing the intraspecific variation and asymmetry within the individual of relative positions of forewing veins in ten species of elachistid moths. Both the intraspecific variation and intra-individual asymmetry were found to be greater than the differences frequently used as systematic characters on various levels within Elachistidae, and to some extent in other Lepidoptera. At least in Elachistidae, major alterations to the current classification will have to be made. Wing characters subject to intraspecific variation should not be used to delimit groups unless they are based on examination of population samples and supported by other characters.  相似文献   
18.
1. Weather‐related episodic events are typically unpredictable, and their duration is often short. Abiotic and biological responses are often missed in routine monitoring. These responses are, however, now of particular relevance given projected changes in extreme weather conditions. 2. We present data from high‐frequency monitoring stations from lakes in Europe, North America and Asia that illustrate two classes of abiotic effects of weather events: (i) generally short‐lived effects of storms on lake thermal structure and (ii) the more prolonged effects of high rainfall events on dissolved organic matter levels and water clarity. We further relate these abiotic effects to changes in dissolved oxygen or in chlorophyll a levels. 3. Three differing causes for weather‐related decreases in surface dissolved oxygen levels were observed: (i) entrainment of anoxic water from depth, (ii) reduction in primary productivity and (iii) increased mineralisation of organic carbon delivered from the catchment. 4. The duration of in‐lake effects tended to be longer for events driven by weather conditions with a longer return period, that is, conditions that were relatively more severe and less frequent at a site. While the susceptibility of lakes to change was related in part to the severity of the meteorological drivers, the impacts also depended on site‐specific factors in some cases. 5. The availability of high‐frequency data at these sites provided insight into the capacity of the lakes to absorb current and future pressures. Several of the changes we observed, including increases in carbon availability, decreases in photosynthetically active radiation and increased disturbance, have the capacity to shift lakes towards an increased degree of heterotrophy. The magnitude and direction of any such change will, however, also depend on the magnitude and direction of climate change for a given location and on lake and catchment characteristics.  相似文献   
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