Miracle-dz/UniFAR-FTUs huggingface dataset:
Pinus virginiana invasion influences soils and arbuscular mycorrhizae of a serpentine grassland1

Abstract Serpentine grasslands support a unique endemic flora composed of many rare species that are tolerant of the inhospitable soil conditions characteristic of ultramafic soils. In the eastern United States, rare plants of many serpentine grasslands are being displaced as a result of invasion by Pinus species and consequent changes in environmental conditions. Community structure and function of symbiotic soil arbuscular mycorrhizal fungi (AMF) also may be affected by Pinus succession. This study examined changes in soil properties, AMF communities, and plant growth in serpentine grassland soils that have been invaded by Virginia pine (Pinus virginiana Mill.). Sites representing three vegetation types (grassland, pine savanna, and pine woodland) were assessed at the Soldiers Delight Natural Environmental Area, Maryland, USA. In comparison to grassland sites, soil pH and concentrations of Ca, Mg, and Ni were reduced in pine woodland soils. Savanna soils exhibited an increase in Mg and Ni concentrations relative to grasslands. In greenhouse experiments, Mg toxicity imposed the largest limitation to plant growth on these serpentine soils, expressed most dramatically in savanna soils, where Mg concentrations were as high as 1,575 µg g−1 soil. Plant growth was least constrained on soil from pine woodlands. Pot cultures from grassland soils yielded the greatest AMF species richness and sporulation. Richness and sporulation were reduced in savanna and pine woodland soils, although pine invasion did not alter fungal diversity indices. The negative impact that pines had in the early stages of succession on fungal abundance and plant growth, along with the decreased serpentine signal seen in woodland soils, have important implications for the restoration and management of plant species diversity on these serpentine sites. Altered soil chemistry and depleted AMF populations may be factors that function to limit the success of herbaceous vegetation adapted to serpentine soils.
Where Are You From? An Investigation Into the Intersectionality of Accent Strength and Nationality Status on Perceptions of Nonnative Speakers in Britain

We explore how interpersonal and intergroup perceptions are affected by a nonnative speaker’s accent strength and the status of their home country. When nationality information was absent (Study 1), natives who heard a strong (vs. weak) accent rated the speaker as warmer but immigrants as a group as more threatening. This result was replicated when the speaker’s nationality was familiar (Study 2) but in this study, country status further shaped accent-based perceptions: the strong (vs. weak) accented speaker evoked more positive interpersonal perceptions when her country status was low, but more negative intergroup perceptions when her country status was high. When the status of the speaker’s nationality was manipulated (Study 3), we replicated the interpersonal perceptions found in Study 1 and the intergroup perceptions found in Study 2. Findings support a holistic approach to investigating perceptions of nonnative speakers: one that considers nationality as well as accent strength.
The dynamic response of soil respiration to land‐use changes in subtropical China

Assessing the impact of land‐use changes on soil respiration (RS) is of vital significance to understand the interactions between belowground metabolism and regional carbon budgets. In this study, the monthly in situ RS was examined between 09:00 and 12:00 hours over a 3‐year period within a representative land‐use sequence in the subtropical region of China. The land‐use sequence contained natural forest (control treatment), secondary forest, two plantations, citrus orchard and sloping tillage land. Results showed that the RS exhibited a distinct seasonal pattern, and it was dominantly controlled by the soil temperature. After the land‐use conversion, the apparent temperature sensitivity of RS (Q10) was increased from 2.10 in natural forest to 2.71 in sloping tillage land except for an abnormal decrease to 1.66 in citrus orchard. Contrarily, the annual RS was reduced by 32% following the conversion of natural forest to secondary forest, 46–48% to plantations, 63% to citrus orchard and 50% to sloping tillage land, with the average reduction of 48%. Such reduction of annual RS could be explained by the decrease of topsoil organic carbon and light‐fraction organic carbon storages, live biomass of fine root (<2 mm) and annual litter input, which indirectly/directly correlated with plant productivity. Our results suggest that substrate availability (e.g., soil organic carbon and nutrients) and soil carbon input (e.g., fine root turnover and litterfall) through plant productivity may drive the RS both in natural and managed ecosystems following strong disturbance events.
Trellising System and Cane Density Affect Yield and Fruit Quality of Red Raspberry

Trellising and cane density treatments were applied to vigorous raspberry (Rubus idaeus L.) cv. Titan plants in Southern Ontario to determine their effects on yield, yield potential, and canopy microclimate during the 1997 and 1998 seasons. The trellising treatments compared were hedgerow (control), V-trellis, and single-sided shift-trellis (shift-trellis). Cane densities (9, 16, 23, and 30 canes/m 2 ) were established before budbreak each season. The treatments significantly affected yield and yield components. Path analysis indicated that interrelationships among yield components were significantly affected by trellising system. In the second season, plants trained on the V-trellis yielded more than did those in a hedgerow system, while those trained on a shift-trellis had the lowest yield because of a smaller fruiting framework. Fruit quality was lower on the shift- trellis than in the other two systems. These differences were related to light penetration into the three canopies. While an optimum cane density was not found for any system, the maximum cane density (30 canes/m 2 ) produced the highest yields. Yield potential per cane decreased as cane density increased; however, the increase in cane number compensated for this decrease, resulting in an increase in total yield per unit area. Fruit quality also decreased as cane density increased, but cane density did not affect canopy microclimate.
Arterial Destiffening Starts Early after Renal Artery Denervation

Introduction Renal artery denervation (RDN) is a new widely discussed method in treatment of hypertension. Most of the RDN studies assessed BP and arterial changes 3 and 6 months after the procedure, but there is a lack of trials that investigated early changes after RDN. Aim To investigate aortic stiffness 24-48 hours after the procedure and thus to examine whether RDN might have an early additive value for a cardiovascular risk decline beyond the lowering of blood pressure. Methods RDN was performed for 73 patients with resistant hypertension. Arterial stiffness and central haemodynamics were measured before the procedure, the next day after the procedure, and subsequently after 1, 3, 6, and 12 months. Results Within 48 hours, RDN significantly reduced aortic pulse wave velocity (AoPWV) from 11.3±2.7 to 10.3±2.6 m/s (p=0.001); reduction was sustained at months 1, 3, 6, and 12. Early changes in the AoPWV value did not correlate with changes in office systolic or diastolic BP (p=0.45; p=0.33). Furthermore, the higher the initial AoPWV value, the greater the reduction of AoPWV observed after 6 months: Q1 8.4±1, Δ0. 05±1.6 / Q2 10.1±0.4, Δ1. 1±1.4 / Q3 12.2±0.8, Δ1. 8±1.7 / Q4 15.3±1.7, Δ2. 8±2.1 (p=0.002). Conclusions Early and sustained effects on AoPWV observed in our study suggest that RDN may have additional effects on reducing arterial stiffness and cardiovascular risk.
The role of the rdxA gene in the evolution of metronidazole resistance in Helicobacter pylori

It was recently demonstrated that inactivation of the rdxA gene, which encodes an oxygen-insensitive NADPH nitroreductase, is associated with the development of resistance to metronidazole by Helicobacter pylori. In order to further evaluate the contribution of rdxA to metronidazole resistance, the sequence of the rdxA gene was determined for a series of metronidazole-sensitive and -resistant isolates derived from a single, metronidazole-sensitive strain using an H. pylori mouse model. These strains were cultured from the stomachs of mice experimentally infected with H. pylori strain SS1 and then treated orally with metronidazole. The sequence of the rdxA gene of all 10 sequenced metronidazole-sensitive and two (7%) of the 27 metronidazole-resistant isolates was identical to that of the parental strain. In contrast, the rdxA gene of the other 25 metronidazole-resistant isolates contained between one and three frameshift or missense mutations. This suggests that while the development of metronidazole resistance in H. pylori is frequently associated with mutational inactivation of the rdxA gene, other mechanisms of resistance are likely to exist in this bacterium.
The Danger of Testing by Selecting Controlled Subsets, with Applications to Spoken-Word Recognition

When examining the effects of a continuous variable x on an outcome y, a researcher might choose to dichotomize on x, dividing the population into two sets—low x and high x—and testing whether these two subpopulations differ with respect to y. Dichotomization has long been known to incur a cost in statistical power, but there remain circumstances in which it is appealing: an experimenter might use it to control for confounding covariates through subset selection, by carefully choosing a subpopulation of Low and a corresponding subpopulation of High that are balanced with respect to a list of control variables, and then comparing the subpopulations’ y values. This “divide, select, and test” approach is used in many papers throughout the psycholinguistics literature, and elsewhere. Here we show that, despite the apparent innocuousness, these methodological choices can lead to erroneous results, in two ways. First, if the balanced subsets of Low and High are selected in certain ways, it is possible to conclude a relationship between x and y not present in the full population. Specifically, we show that previously published conclusions drawn from this methodology—about the effect of a particular lexical property on spoken-word recognition—do not in fact appear to hold. Second, if the balanced subsets of Low and High are selected randomly, this methodology frequently fails to show a relationship between x and y that is present in the full population. Our work uncovers a new facet of an ongoing research effort: to identify and reveal the implicit freedoms of experimental design that can lead to false conclusions.
A mitochondrial DNA control region phylogeny of the Cervinae: speciation in Cervus and implications for conservation

Sequences from complete mitochondrial control regions (mtDNA CR) were used to infer phylogenetic relationships in 25 Cervinae taxa. Cervus splits into clades that are partially discordant with current species delimitations. Nominate Cervus elaphus includes two divergent clades that must be referred to as species elaphus (European elaphoid deer) and canadensis (Eurasian and North American wapitoid deer). Cervus nippon splits into Japanese and continental plus Taiwan sika. Père David's deer is nested within Cervus, suggesting that Elaphurus should be merged with Cervus. European and Persian fallow deer are genetically divergent and distinct species. Sequence length varied due to a CR‐I insertion, tandemly repeated twice in rusa and sambar deer, sika and wapiti, and repeated up to six times in a clade of Japanese sika. Variable copy numbers of this repeat are also fixed in different sika subspecies, and could be used as a diagnostic marker for subspecies. Sequence variability at the mtDNA CR is informative for defining species and subspecies boundaries, and for locating the geographical origin of captive‐reared stocks. Natural and farmed populations of some species have been deeply affected by human management and the conservation of deer populations would be aided by the appropriate identification of the different evolutionary and taxonomic units.
Computational Contact Mechanics

This paper describes modern techniques used to solve contact problems within Computational Mechanics. On the basis of a continuum description of contact, the mathematical structure of the contact formulation for finite element methods is derived. Emphasis is also placed on the constitutive behavior at the contact interface for normal and tangential (frictional) contact. Furthermore, different discretization schemes currently applied to solve engineering problems are formulated for small and finite strain problems. These include isoparametric interpolations, node-to-segment discretizations and also mortar and Nitsche techniques. Furthermore, several algorithms related to spatial contact search and fulfillment of the inequality constraints at the contact interface are discussed. Here, especially the penalty and Lagrange multiplier schemes are considered and also SQP- and linear-programming methods are reviewed. Keywords: contact mechanics; friction; penalty method; Lagrange multiplier method; contact algorithms; finite element method; finite deformations; discretization methods
Analysis of water content and dynamic properties in model studies on selected porcine muscles

A b s t r a c t . The paper presents an analysis of the effect of curing brine composition on the water properties in sediments from pork shank and semi-membranous muscles. The applied brines were solutions of inorganic salts of varying composition. The performed analyses comprised active acidity pH, water activity Aw, water absorbability expressed as percentage proportion of free water in the total water content, as well as the value of relaxation times spin-network T 1 and spin-spin T 2. An inversely proportional correlation was found between pH values and water activity in the examined muscles when brines containing sodium chloride, pyrophosphate, tripolyphosphate and a mixture of NaCl and pyrophosphate were applied. In the case of the control muscles as well as those containing a mixture of sodium chloride and tripolyphoshate, the above correlation was directly proportional. It was demonstrated that pyrophosphate, even at low pH values, significantly increased water absorbability of muscle tissue sediments. The analysis of relaxation parameters showed that pyrophosphate as a constituent of brine reduced the content of free water in relation to bound water as demonstrated by significant shortening of the spin-network relaxation time. In addition, the molecular dynamics of bound water was found to be inhibited. The above observations allowed the authors to conclude that pyrophosphate, as brine constituent, causes very good water binding in muscle tissue sediments. K e y w o r d s : water activity, water holding capacity, relaxation times
Biogeography meets conservation: the genetic structure of the endangered lycaenid butterfly Lycaena helle (Denis & Schiffermuller, 1775)

Cold-adapted species are thought to have had their largest distribution ranges in central Europe during the glacial periods. Postglacial warming caused severe range shifts of such taxa into higher latitudes and altitudes. We selected the boreomontane butterfly Lycaena helle (Denis & Schiffermuller, 1775) as an example to demonstrate the genetic effects of range changes, and to document the recent status of highly fragmented remnant populations. We analysed five polymorphic microsatellite loci in 1059 individuals sampled at 50 different localities scattered over the European distribution area of the species. Genetic differentiation was strong among the mountain ranges of western Europe, but we did not detect similarly distinct genetic groups following a geographical pattern in the more eastern areas. The Fennoscandian populations form a separate genetic group, and provide evidence for a colonization from southern Finland via northern Scandinavia to south-central Sweden. Species distribution modelling suggests a large extension of the spatial distribution during the last glacial maximum, but highlights strong retractions to a few mountain areas under current conditions. These findings, combined with our genetic data, suggest a more or less continuous distribution of L. helle throughout central Europe at the end of the last ice age. As a consequence of postglacial warming, the species retreated northwards to Fennoscandia and escaped increasing temperatures through altitudinal shifts. Therefore, the species is today restricted to population remnants located at the mountain tops of western Europe, genetically isolated from each other, and evolved into genetically unique entities. Rising temperatures and advancing habitat destruction threaten this wealth of biodiversity. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 155-168. ADDITIONAL KEYWORDS: climate change - fragmentation - Lepidoptera - microsatellites - mountains - postglacial relict - range shift - species distribution modelling.
Genetic diversity and mating system in a tropical tree, Carapa guianensis (Meliaceae)

Carapa guianensis Aublet. (Meliaceae) is an abundant, canopy tree species often exported as fine wood products. The populations in the Atlantic coastal plain ofCosta Rica have undergone a wide variety ofhuman-induced changes in distribution and abundance, including isolation due to deforestation. Using protein electrophoretic analysis of seeds, we investigated the genetic variability and population differentiation of nine populations and the outcrossing rate in two populations that differed in density by a factor of 50%. Average polymorphism (35%) and heterozygosity (0.12) across populations were relatively low in comparison with other tropical tree species. Only 4.6% of the total genetic variability could be attributed to population differentiation even though populations were separated by as much as 70 km. However, genetic differentiation did increase with distance between pairs of compared populations. There were no apparent differences in genetic variation between logged and unlogged forests. The outcrossing rate for each population was not significantly different from 1.0, but there was evidence of nonrandom mating in the lower density population. High levels of gene flow are probably maintained by seed dispersal as seeds travel well throughout flooded forests and rivers. High population density and synchronous flowering also contribute to high outcrossing rates. These genetic characteristics suggest that Carapa guianensis is a good candidate for natural forest management where it occurs at high density. However, current management practices need to account for the rapid rate of deforestation occurring around managed natural forest sites that will result in the elimination of intervening populations.
Paludification dynamics in the boreal forest of the James Bay Lowlands: effect of time since fire and topography

In many northern forest ecosystems, soil organic matter accumulation can lead to paludification and forest pro- ductivity losses. Paludification rate is primarily influenced by topography and time elapsed since fire, two factors whose in- fluence is often confounded and whose discrimination would help forest management. This study, which was conducted in the black spruce (Picea mariana (Mill.) BSP) boreal forest of northwestern Quebec (Canada), aimed to (1) quantify the ef- fect of slope and time since fire on paludification rates, (2) determine whether soil organic layer depth could be estimated by surface variables that can potentially be remotely sensed, and (3) relate the degree of paludification to tree productivity. In this study, soil organic layer depth was used as an estimator of the degree of paludification. Slope and postfire age strongly affected paludification dynamics. Young stands growing on steep slopes had thinner organic layers and lower or- ganic matter accumulation rates compared with young stands growing on flat sites. Black spruce basal area and Sphagnum cover were strong predictors of organic layer depth, potentially allowing mapping of paludification degree across the land- scape. Tree productivity was negatively related to organic layer depth (R 2 = 0.57). The equations developed here can be used to quantify forest productivity decline in stands that are undergoing paludification, as well as potential productivity re- covery given appropriate site preparation techniques.
Production of Endemic Microcrustacean Phronima Suppa (Phronima sp) to Subtitute Artemia salina in Tiger Prawn Cultivation

Phronima suppa (Phronima sp.) belongs to an endemic microcrustacea species inhabiting certain brackish water pond in Wiringtasi Village, Suppa Sub-district, Pinrang Regency, Indonesia. It has an important role to increase vitality and immunity of tiger prawn (Penaeus monodon) and to improve environmental quality of the brackish water pond. This species has potential chance to substitute the use of Artemia. Population of Phronima suppa in nature fluctuates, falls and even perishes after around 15 days. This study aims to produce Phronima suppa to be used as inoculant in the prawn brackish water pond and to substitute the use of Artemia in hatchery. The study is conducted in May to November, 2013 in the Field Laboratory of Fisheries and Maritime Science, Muslim University of Indonesia in Pinrang Regency. Phronima suppa is cultivated in controlled basin under treatment (A) by Chlorella sp, treatment (B) by Chaetoceros sp, and treatment (C) by combining Chlorella sp and Chaetoceros sp. Observed variables consist of production and water quality. The study is designed in form of Completely Randomized Design (CRD) by three treatments, while each of the treatments consist of three repetitions. Combination of Chlorella sp and Chaetoceros sp (treatment C) delivers the highest production by 35.67 ± 15.01 individual/l followed by treatment B by 34.67 ± 7.51 individual/l and treatment A by 27.35 ± 0.57 individual. This production increases in day 17 up to day 24. Productive period of Phronima suppa in the controlled basin is longer than in endemic habitat.
Biochemical models of leaf photosynthesis.

Increasing concerns of global climate change have stimulated research interests in all aspects of carbon exchange. This has restored interest in leaf photosynthetic models to predict and assess changes in photosynthetic CO2 assimilation in different environments. This is a comprehensive presentation of the most widely used models of steady-state photosynthesis by an author who is a world authority. Treatments of CO3, CO4 and intermediate pathways of photosynthesis in relation to environment have been update to include work on antisense transgenic plants. It will be a standard reference for the formal analysis of photosynthetic metabolism in vivo by advanced students and researchers.
Adaptations to a terrestrial existence in the Robber Crab Birgus latro L. II. In vivo respiratory gas exchange and transport

The lungs are responsible for essentially all uptake of oxygen in Birgus latro . Elimination of CO 2 in resting crabs appears to occur largely across the gills but during exercise approximately half the output of CO 2 is pulmonary. Pa O 2 was high in resting crabs (43.8 mmHg; 1 mmHg = 133.3 Pa) but fell during exercise (to 27mmHg). Pv O 2 remained constant at 10–12 mmHg. Pa CO 2 rose substantially during exercise (from 7.1 to 14.6mmHg). Haemocyanin delivered 90% of oxygen in resting crabs rising to 97%following exercise. Oxygen delivery at rest was 0.46 mmoll −1 haemolymph rising to 0.72mmoll −1 following exercise. Pigment-bound oxygen capacity was 1.1 mmoll −1 . Oxygen delivery to the tissues was diffusion-limited during exercise. Anaerobic metabolism during exercise raised the concentration of L-lactate in the haemolymph 100-fold (from 0.25 to 25 mmoll −1 ) and concomitantly caused a fall in pH of 0.7 units. This acidosis was partially compensated by the end of the 30-min exercise period.