Miracle-dz/UniFAR-FTUs huggingface dataset:
The influence of predawn leaf water potential on stomatal responses to atmospheric water content at constant Ci and on stem hydraulic conductance and foliar ABA concentrations

Stomata and photosynthetic responses to increasing leaf-to-air vapour pressure difference (V) were investigated in watered and droughted Eucalyptus tetrodonta when either ambient CO2 (Ca) or internal CO2 concentration (Ci) were constant. Stem hydraulic conductance and xylem and foliar abscisic acid levels were measured periodically during the drought period.As V increased, stomatal conductance (gs) declined. Maintaining Ci did not affect the response of Gs to V or predawn leaf water potential (pd). In fully watered plants the decline in gs was insufficient to prevent increased transpiration rates (Et) with increasing V. In contrast, in droughted plants, stomatal closure was sufficient to prevent increasing Et. Stomatal sensitivity to increasing V was increased by drought. As drought developed, the three phases of stomatal responses to V progressively collapsed to one where feedforward mechanisms result in decreasing Et with increasing V. Thus as drought developed the feedforward response of stomata to V entirely dominated.Net photosynthesis (Pn) and gs responded in unison to changes in V and pd. The decline in Pn as V increased, despite Ci being maintained constant, was observed in fully watered plants and in severely droughted plants. Pn was most dependent on gs at large values of V and in droughted plants.As drought progressed and pd declined, stem hydraulic conductance decreased and foliar ABA concentrations increased. The decline in maximum gs was correlated with foliar ABA levels. It is concluded here that hydraulic signals, be they atmospheric water or soil water in origin, and possibly also chemical signals regulate gs, which in turn can limit assimilation rates in seasonally dry savannas.
The ACT-1 plasmid-encoded AmpC β-lactamase is inducible: detection in a complex β-lactamase background

The purpose of this study was to identify the genetic organization and inducibility of bla(ACT-1) in a clinical isolate of Klebsiella pneumoniae possessing at least five different beta-lactamases. The genetic organization of the bla(ACT-1)/ampR region is identical to those of inducible chromosomal ampC genes. RNA analysis using primer extension demonstrated a five-fold increase in bla(ACT-1) transcript production on exposure to cefoxitin. These findings are significant because induction was detected in a complicated beta-lactamase background. In addition, this report is the first to describe an inducible plasmid-encoded AmpC beta-lactamase of Enterobacter cloacae origin.
A Biflavonoid and a Carotenoid from Rhus leptodictya: Isolation, Characterization and Antibacterial Properties

Acetone extracts of the leaves of Rhus Leptodictyawere studied for antibacterial activity using bioautography and micro titre plate assay techniques against four nosocomial bacterial pathogens Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. A bioassay guided fractionation showed that the activity was concentrated in the carbon tetrachloride fraction. A bioautography fingerprint showed that three major compounds were responsible for the antibacterial activity. Two of these compounds were isolated by a combination of solvent - solvent fractionation and chromatographic techniques. They were characterised by 1 HNMR, 13 CNMR and 2DNMR as 2,3-dihydro-amentoflavone, a biflavonoid andlutein, a carotenoid. This is the first report on the isolation of bioactive compounds from Rhus leptodictya.The four test organisms were sensitive to the two bioactive compounds. We found that Gram-positive organisms were more sensitive to 2,3-dihydroamentoflavone with MIC values of 0.03 and 0.02 mg/ml to E. faecalis and S. aureus, respectively; while Gram-negative organisms were more sensitive to Lutein with MIC values of 0.06 and 0.09 to P. aeruginosa and E. coli, respectively. The cytotoxicity was determined using a methyl thiazole tetrazolium (MTT) based colorimetric assay against Vero monkey kidney cells. The MTT assay indicated that the LC50 of 2,3-dihydroxy-amentoflavone to Vero cells was 9.4 µg/ml while the LC50 of lutein was 9.8 µg/ml. Therefore, while the two compounds were very active against test organisms of nosocomial origin, they were also quite toxic.
ABCB1 Genetic Variants as Predictors of Irinotecan-Induced Severe Gastrointestinal Toxicity in Metastatic Colorectal Cancer Patients

Irinotecan is widely used in the treatment of metastatic colorectal cancer (mCRC) despite its severe toxicities. Toxicity is often associated with the UGT1A1*28/*28 genotype. An explanation for idiopathic toxicity beyond the UGT1A1 biomarker, however, remains a major concern for clinicians. One of the main irinotecan transporters is P-glycoprotein (P-gp), which is a hepatic efflux pump encoded by ABCB1. P-gp is involved in the biliary excretion of irinotecan and its active metabolite SN-38. We aimed to assess whether functional variants in ABCB1 also contribute to identifying patients at risk of toxicity. A cohort of 308 mCRC patients treated with irinotecan-based regimens were genotyped for polymorphisms in ABCB1 (rs1128503, rs2032582, and rs1045642). The effect of these variants and their haplotypes on irinotecan-induced severe toxicity (diarrhea, neutropenia, asthenia, nausea, and mucositis) was assessed. After adjusting for the relevant clinical and pathological parameters in the multivariate analysis, we found rs1128503 was significantly associated with severe diarrhea and mucositis (P=0.014 and P=0.002, respectively). Additionally, rs2032582 was associated with severe mucositis (P<0.001). Our results show that rs1128503 genotyping could help to predict severe gastrointestinal toxicity induced by irinotecan.
Prey partitioning between cod (Gadus morhua) and minke whale (Balaenoptera acutorostrata) in the Barents Sea

Abstract Stomach samples of minke whale (Balaenoptera acutorostrata) and cod (Gadus morhua) were collected on the northeastern parts of the Finnmark coast, northern Norway, in 1998 and 1999 to investigate prey preference, niche overlap and niche width for the two species. A survey to estimate prey abundance was also conducted. Prey preference, niche overlap and niche width were described using Manly's alpha (α), Pianka's index (Ojk) and Levin's index (B), respectively. The diet of cod consisted mainly of capelin, deep-water shrimp, gadoids and krill. The smallest cod (≤64 cm length) preferred capelin, whereas the largest cod (>64 cm length) preferred gadoid species, including cod. The minke whale diet consisted mainly of capelin (Mallotus villosus), herring (Clupea harengus) and krill, and showed a particular preference for herring and capelin. Krill were consumed in large quantities, but did not seem to be a preferred food item for either cod or minke whales. In contrast to cod, which fed very little on herring, the minke whale fed heavily on herring in some areas. The niche widths for both cod and minke whales were relatively low, and the diet overlap between minke whale and cod was low.
Applying Protection Motivation Theory to Predict Facebook Users’ Withdrawal and Disclosure Intentions

Because legislation only slowly finds ways to better protect Internet users’ privacy and is heavily country-dependent, self-data protection is of major importance. The current investigation applies the protection motivation theory to investigate factors that predict Facebook users’ privacy protection motivation and to examine whether fear appeals and social norms can raise participants’ intention to protect personal data. In a 2 (warning vs. neutral message) x 3 (high vs. low norms vs. control) online experiment (N = 304), participants were told they would receive a personalized privacy protection recommendation based on their Facebook profile's privacy settings. Whereas neither the fear appeal nor high social norms led to an increase in privacy protection motivation, analyses revealed that privacy threat perception and the perceived effectiveness of privacy protection are important factors for explaining self-withdrawal intention among Facebook users.
Genomics of Heat Tolerance in Reproductive Performance Investigated in Four Independent Maternal Lines of Pigs

Improving swine climatic resilience through genomic selection has the potential to minimize welfare issues and increase the industry profitability. The main objective of this study was to investigate the genetic and genomic determinism of tolerance to heat stress in four independent purebred populations of swine. Three female reproductive traits were investigated: total number of piglets born (TNB), number of piglets born alive (NBA) and average birth weight (ABW). More than 80,000 phenotypic and 12,000 genotyped individuals were included in this study. Genomic random-regression models were fitted regressing the phenotypes of interest on a set of 95 environmental covariates extracted from public weather station records. The models yielded estimates of (genomic) reactions norms for individual pigs, as indicator of heat tolerance. Heat tolerance is a heritable trait, although the heritabilities are larger under comfortable than heat-stress conditions (larger than 0.05 vs. 0.02 for TNB; 0.10 vs. 0.05 for NBA; larger than 0.20 vs. 0.10 for ABW). TNB showed the lowest genetic correlation (-38%) between divergent climatic conditions, being the trait with the strongest impact of genotype by environment interaction, while NBA and ABW showed values slightly negative or equal to zero reporting a milder impact of the genotype by environment interaction. After estimating genetic parameters, a genome-wide association study was performed based on the single-step GBLUP method. Heat tolerance was observed to be a highly polygenic trait. Multiple and non-overlapping genomic regions were identified for each trait based on the genomic breeding values for reproductive performance under comfortable or heat stress conditions. Relevant regions were found on chromosomes (SSC) 1, 3, 5, 6, 9, 11, and 12, although there were important regions across all autosomal chromosomes. The genomic region located on SSC9 appears to be of particular interest since it was identified for two traits (TNB and NBA) and in two independent populations. Heat tolerance based on reproductive performance indicators is a heritable trait and genetic progress for heat tolerance can be achieved through genetic or genomic selection. Various genomic regions and candidate genes with important biological functions were identified, which will be of great value for future functional genomic studies.
Color as related to Size, Sex, and Behavior in seven Caribbean Labrid Fish Species (genera Thalassoma, Halichoeres and Hemipteronotus)

Approximately 5500 Caribbean labrid fishes belonging to seven species were caught, transported, partly on ice, to the laboratory and subsequently studied. The major portion was examined immediately; some 20 per cent were stored briefly (less than three days) at minus 20°C. Color pattern (and shape of fins) may change during adult life, varying from slightly Halichoeres poeyi) to drastically Thalassoma bifasciatum). Per species a classification into successive color phases has been introduced; these color phases are strongly related to body length. In Halichoeres maculipinna, Hemipteronotus splendens and Hemipteronotus martinicensis females are restricted to the small, first adult color phase; males have exclusively been found in the larger intermediate and terminal color phases. This confirms the prevailing opinion that labrid dichromatism represents a sexual dimorphism. In Halichoeres poeyi females are also significantly smaller than males. In the most abundant species, however, sex and color/size are not clearly related. In Thalassoma bifasciatum and Halichoeres bivittatus two types of males occur, as functional males are present in both the small, first adult color phase and in the large, terminal color phase. Functional females have been found in all sizes and colors in Halichoeres bivittatus and Halichoeres garnoti. Sex reversal from female towards male sex – a common process in all species – occurs more or less coincidental to color change. As distinct from the Sparidae, Scaridae or Serranidae the reversal proceeds via a total decline of the transforming ovary. Consequently, temporary stages of functional hermaphroditism do not occur in Labridae.
Relationships between stream macroinvertebrates and environmental variables at multiple spatial scales

Summary 1. Aquatic communities are structured by multiple forces, and identifying the driving factors over multispatial scales is an important research issue. The East Asian monsoon region is globally one of the richest environments in terms of biodiversity, and is undergoing rapid human development, yet the river ecosystems in this region have not been well studied. We applied a hierarchical framework to incorporate regional and local environmental effects on stream macroinvertebrate communities in this region. The knowledge gained is expected to improve the understanding of the importance of spatial scale on regional and local diversity in the East Asian monsoon region. 2. A national data set of benthic macroinvertebrates and environmental variables (geographical, land-use, hydrological, substratum and physicochemical elements) in Korean rivers was used to determine the habitat preferences of macroinvertebrates. 3. Latitude, proportion of forest coverage, riffle habitat, silt substratum and temperature were the most important determinants for the ordinations of macroinvertebrate communities in each category evaluated by canonical correspondence analysis (CCA). The optimal habitats for stream macroinvertebrates are not the same for all species, and overall community metrics and abundance of sensitive species tended to be lower in open agricultural and urban streams than in forested streams. The sensitivity of mayflies and stoneflies to anthropogenic disturbances implicated them as good indicators to assess the effects of urban and agricultural activities. 4. A partial CCA was used to evaluate the relative importance of macrohabitat and microhabitat variables on community composition at three spatial scales (whole country, the large Han River basin and two small sub-basins in the lowlands and highlands). The majority of community variation (17–22% for each environmental element) was explained by macrohabitat variables at the regional spatial scale. In contrast, large proportions (15–18%) were explained by microhabitat variables at the local spatial scale. 5. Our findings indicate that the relative importance of habitat scales should be determined by geographical size and that comprehensive understanding of multispatial scale patterns can be important for implementing sound biodiversity conservation programmes.
Nrl is dispensable for specification of rod photoreceptors in adult zebrafish contrasting a deeply conserved requirement earlier in ontogeny

The transcription factor NRL (Neural Retinal Leucine-zipper) has been canonized, appropriately enough, as the master regulator of photoreceptor cell fate in the retina. NRL is necessary and sufficient to specify rod cell fate and to preclude cone cell fate in mice. By engineering zebrafish we tested if NRL function has conserved roles beyond mammals or beyond nocturnal species, i.e. in a vertebrate possessing a greater and more typical diversity of cone sub-types. Here, transgenic expression of a Nrl homolog from zebrafish or mouse was sufficient to convert developing zebrafish cones into rod photoreceptors. Zebrafish nrl-/- mutants lacked rods (and had excess UV-sensitive cones) as young larvae, thus the conservation of Nrl function between mice and zebrafish appears sound. These data inform hypotheses of photoreceptor evolution through the Nocturnal Bottleneck, suggesting that a capacity to favor nocturnal vision is a property of NRL that predates the emergence of early mammals. Strikingly, however, rods were abundant in adult nrl-/- null mutant zebrafish. Rods developed in adults despite Nrl protein being undetectable. Therefore a yet-to-be-revealed non-canonical pathway independent of nrl is able to specify the fate of some rod photoreceptors. Highlights - Nrl is conserved and sufficient to specify rod photoreceptors in zebrafish retina - Nrl is necessary for rod photoreceptors in early ontogeny of zebrafish larvae - Zebrafish Nrl is functionally conserved with mouse and human NRL - Remarkably, Nrl is dispensable for rod specification in adult zebrafish
The use of matK in Ophioglossaceae Phylogeny and the Determination of Mankyua Chromosome Number Shed Light on Chromosome Number Evolution in Ophioglossaceae

Abstract The chromosome number and phylogenetic position of the monotypic eusporangiate genus Mankyua (Ophioglossaceae), which shares peculiar morphological characteristics with Ophioglossum s.l. and Helminthostachys, were determined. Meiotic and mitotic chromosome observations of Mankyua show n = 130 and 2n = ca. 260, suggesting that the base number of this genus is x = 130, which is a new finding and the highest base number reported so far for Ophioglossaceae. The molecular phylogenetic trees derived from nucleotide sequence variation of rbcL and matK genes differ in terms of the phylogenetic position of Mankyua. The molecular phylogenetic trees based on combined data sets of rbcL and matK suggest that Mankyua might be the earliest-diverging lineage of Ophioglossaceae.
The influence of stimulation frequency on force‐velocity characteristics of in situ rat medial gastrocnemius muscle

Force (and power)-velocity characteristics were determined at different stimulation frequencies in th situ rat muscle with nerve stimulation at 36 degrees C. In isometric contractions (duration, 150 ms), maximal force is generated at approximately 120 Hz. In contrast, in the high velocity (250 mm s-1) shortening contractions, frequencies of approximately 400 Hz were needed to obtain maximal dynamic force, while 120 Hz elicited only approximately 26% of the maximum. At the highest velocity measured, power production was significantly different (P < 0.05) among frequencies of 80, 120, 200 and 400 Hz, suggesting that maximal shortening velocity should be assessed using very high stimulation frequencies. However, the results further indicate that lower frequencies may be adequate in exercise studies that investigate fatigue and changes in power output during series of repetitive contractions.
No latitudinal gradients in tempo or mode of morphological evolution in birds

The latitudinal diversity gradient is one of the most striking patterns in nature yet its implications for morphological evolution are poorly understood. In particular, it has been proposed that an increased intensity of species interactions in tropical biota may either promote or constrain trait evolution, but which of these outcomes predominates remains uncertain. Here, we develop tools for fitting phylogenetic models of phenotypic evolution in which the impact of species interactions can vary across lineages. Deploying these models on a global avian trait dataset to explore differences in trait divergence between tropical and temperate lineages, we find that the effect of latitude on the mode and tempo of morphological evolution is weak and clade- or trait-dependent. Our results indicate that species interactions do not disproportionately impact morphological evolution in tropical bird families and question the validity and universality of previously reported patterns of slower trait evolution in the tropics.
Identifying Environmental Risk Factors for Louping Ill Virus Seroprevalence in Sheep and the Potential to Inform Wildlife Management Policy

Identifying the risk factors for disease is crucial for developing policy and strategies for controlling exposure to pathogens. However, this is often challenging, especially in complex disease systems, such as vector-borne diseases with multiple hosts and other environmental drivers. Here we combine seroprevalence data with GIS-based environmental variables to identify the environmental risk factors associated with an endemic tick-borne pathogen—louping ill virus—in sheep in Scotland. Higher seroprevalences were associated with (i) upland/moorland habitats, in accordance with what we predicted from the habitat preferences of alternative LIV transmission hosts (such as red grouse), (ii) areas of higher deer density, which supports predictions from previous theoretical models, since deer are the key Ixodes ricinus tick reproduction host in this system, and (iii) a warmer climate, concurring with our current knowledge of how temperature affects tick activity and development rates. The implications for policy include adopting increased disease management and awareness in high risk habitats and in the presence of alternative LIV hosts (e.g., grouse) and tick hosts (especially deer). These results can also inform deer management policy, especially where there may be conflict between contrasting upland management objectives, for example, revenue from deer hunting vs. sheep farmers.
The homogeneity of right-wing populist and radical content in YouTube recommendations

The use of social media to disseminate extreme political content on the web, especially right-wing populist propaganda, is no longer a rarity in today's life. Recommendation systems of social platforms, which provide personalized filtering of content, can contribute to users forming homogeneous cocoons around themselves. This study investigates YouTube's recommendations system based on 1,663 German political videos in order to analyze the homogeneity of the related content. After examining two datasets (right-wing populist and politically neutral videos), each consisting of ten initial videos and their first and second level recommendations, we show that there is a high degree of homogeneity of right-wing populist and neutral political content in the recommendation network. These findings offer preliminary evidence on the role of YouTube recommendations in fueling the creation of ideologically like-minded information spaces.
Disturbance and regeneration dynamics of an old‐growth North Patagonian rain forest in Chiloé Island, Chile

1 Few studies have addressed the mechanisms of coexistence of shade‐tolerant and intolerant tree species in the canopy of old‐growth, lowland rain forests of southern South America. We explored the hypothesis that their forest dynamics result from frequent, single tree‐fall gap episodes. 2 We analysed the disturbance regime and assessed the regeneration modes of shade‐tolerant and intolerant canopy trees in a lowland, old growth North Patagonian rain forest in Chiloé Island (42° S) using dendroecological methods. 3 Dominant canopy trees were the shade‐intolerant Nothofagus nitida (Fagaceae), Drimys winteri (Winteraceae) and the tolerant Podocarpus nubigena (Podocarpaceae). The oldest individuals, however, were represented by Saxegothaea conspicua, Podocarpaceae (shade tolerant > 498 years) and Weinmannia trichosperma, Cunoniaceae (intolerant > 382 years). Shade‐tolerant species have regenerated continuously for the past 400 years, but recruitment of shade‐intolerant species has increased only in the past 50 years. These regeneration patterns suggest a lack of catastrophic disturbance, at least since 1650. 4 Analysis of tree radial growth patterns revealed frequent moderate releases of both shade‐tolerant and intolerant tree species, consistent with frequent small‐scale disturbances, such as individual tree‐fall gaps. Increased releases, peaking in 1940 and followed by enhanced recruitment, may be a consequence of individual tree‐falls induced by low‐intensity windstorms or limited selective logging. Such disturbances have occurred for at least 250 years, but have had little overall effect on stand structure and canopy composition. 5 The replacement and coexistence of shade‐tolerant and intolerant tree species in the canopy of this North Patagonian forest can be explained by frequent small‐scale disturbances (i.e. gap‐phase dynamics) and by the absence of large‐scale natural or anthropogenic disturbances over the past four centuries.