Miracle-dz/UniFAR-FTUs huggingface dataset:
Ineffectively and Effectively Nodulated Alfalfas Demonstrate Biology Nitrogen Fixation Continues with High Nitrogen Fertilization

Estimates of biological nitrogen fixation (BNF) require a non-N 2 -fixing control preferably of the same species as the crop under evaluation. A field experiment was conducted to evaluate two ineffectively nodulated alfalfa (Medicago sativa L.) germplasms as non-N 2 -fixing controls for estimating BNF under increasing N fertilizer applications. «Ineffective Agate» and «Ineffective Saranac» and their effective parental cultivars, Agate and Saranac, were planted in field plots at Rosemount, MN, in 1985 and 1986. Forage yields were taken in each study at early bloom for 2 yr. Plots received four rates of ammonium nitrate (0, 70, 140, and 210 kg N ha −1 ) after each harvest. Biological nitrogen fixation in the 1986 plots was estimated by both the 15 N isotope dilution technique and the difference method. In the presence of adequate inorganic N, ineffectively nodulated plants were comparable to their effective counterparts in herbage yield and N content. No difference in herbage yield or N content at any N fertilixer treatment was observed between Ineffective Agate and Ineffective Saranac, indicating that the two entries would be comparable non-fixing controls for field assessment of BNF. The isotope dilution technique and the difference method gave comparable estimates of the change in BNF with applied N. Estimates of BNF declined in both Agate and Saranac in response to increasing N fertilization, but continued at high rates at the highest fertilizer N addition. A first production year stand of alfalfa under an annual N application rate of 840 kg/ha obtained 20 to 25% of its N from BNF. This is the first report that BNF continues with high levels of N application
Predation by the naticid gastropod Polinices lewisii (Gould) on littleneck clams Protothaca staminea (Conrad) in British Columbia

Feeding rates and prey-size selection of the predatory naticid snail Polinices lewisii (Gould) on the littleneck clam Protothaca staminea (Conrad) were studied on the west coast of British Columbia. Caging experiments indicated that few clams of the smallest size class (10–35 mm shell length) were drilled by Polinices lewisii; predation was heaviest on clams in the size range 35–50 mm. Feeding rates of P. lewisii did not vary significantly over the range of densities provided in field experiments, nor were they influenced by the close proximity of other moon snails. Feeding rates were relatively low. Summer feeding rates of P. lewisii indicated a correlation with respect to snail size, and results from the annual study indicated a seasonal trend towards reduced consumption during the winter months. Polinices lewisii, feeding on P. staminea, was estimated to eat 0.1% of its own dry mass per day. Information from recovered shells of drilled clams showed that the diameter of boreholes was correlated with sna.
African penguins as predators and prey – coping (or not) with change

African penguins Spheniscus demersus live in the Benguela and western Agulhas ecosystems off southern Africa. Their numbers decreased throughout the 20th century from at least 1.5 million to about 0.18 million adults, although different regional trends were apparent. They feed to a large extent on shoaling epipelagic fish, notably anchovy Engraulis capensis and sardine Sardinops sagax, and regional trends in the abundance of penguins are associated with trends in the abundance and distribution of these prey fish. Many first-time breeders emigrate from colonies where feeding or other conditions at the time are unfavourable to more favourable breeding localities. This has led to both the extinction and formation of colonies. Food now may limit colonies at relatively small sizes, a fact attributable to industrial fisheries reducing the densities of forage fish. African penguins share their habitat with several other predators, with which they compete for food and breeding space. One of these, the Cape fur seal Arctocephalus p. pusillus, increased through the 20th century to 1.5 – 2 million animals at its close. Reported observations of predation by fur seals on seabirds have increased in recent decades and threaten the continued existence of small colonies of penguins. Stochastic modelling suggests that colonies of 10 000 pairs have a 9% probability of extinction in 100 years, so smaller populations should be regarded as "Vulnerable". However, in a period of prolonged food scarcity off southern Namibia, the regional population decreased from more than 40 000 pairs in 1956 to about 1 000 pairs in 2000, and many colonies numbering less than 1 000 pairs became extinct. The minimum viable population for African penguins is currently considered to be >40 000 pairs, likely of the order of 50 000 pairs, a figure equivalent to its level in 2000. The chance of survival of the species through the 21st century is tenuous.
Experimental Analysis of Intermediate Disturbance and Initial Floristic Composition: Decoupling Cause and Effect

The intermediate disturbance hypothesis predicts that richness will be highest in communities with moderate levels of disturbance and at intermediate time spans following disturbance. This model was proposed as a nonequilibrium explanation of species richness in tropical forests and coral reefs. A second model of succession, initial floristic composition, states that nearly all species, including late seral species, are present at the start of suc- cession. This leads to the prediction that richness should be highest immediately following disturbance. We tested these predictions using plant species composition data from two long-term field experiments in North American tallgrass prairie vegetation. In contrast to one prediction of the intermediate disturbance hypothesis, there was a significant monotonic decline in species richness with increasing disturbance frequency, with no evidence of an optimum, in both field experiments. Species composition on an annually burned site was a subset of that of infrequently burned sites. The average number of species per quadrat and the number of grass, forb, and annual species were lowest on annually burned sites compared to unburned sites and sites burned once every 4 yr. The second prediction of the intermediate disturbance hypothesis, however, was supported. Richness reached a maximum at an intermediate time interval since the last disturbance. This contradicts the prediction from the initial floristic composition model of succession. These results also suggest that the two predictions of the intermediate disturbance hypothesis are independent and unre- lated. We propose that this may be explained by uncoupling the effects of disturbance as a single, relatively discrete event from system response to disturbance. From this perspec- tive, disturbance becomes an extinction-causing event in these grasslands, whereas recovery following disturbance is a balance between immigration and extinction.
The taxonomy of two host-specific, cryptic dendronotoid nudibranch species (Mollusca : Gastropoda) from Australia including a new species description

Two host-specific, extremely cryptic, small dendronotoid nudibranchs from Australia are described and classified, and their phylogenetic position within the superfamily is discussed. Lomanotus vermiformis Eliot 1908 subsists exclusively on the hydrozoan Lytocarpus philippinus (Kirchenpauer, 1872). Lomanotus stauberi Clark & Goetzfried 1976 is newly synonymized with L. vermiformis. Marioniopsis platycteneasp. nov. subsists exclusively on the alcyonacean Parerythropodium hicksoni Utinomi 1972. Marianina rosea (Pruvot-Fol 1930) is relocated to the Tritoniidae (wherein it forms a monotypic subfamily, Marianinae) because of possession of palmate rhinophoral clavi, the principal apomorphy of the Tritoniidae. The validity of using the form of the digestive gland as a basis for dividing the Tritoniidae is questioned since it is acknowledged that this organ has progressed from a solid (holohepatic) arrangement to a dispersed (cladohepatic) arrangement in parallel in several major nudibranch lineages; form thus offers merely homoeoplaseous phylogenetic characters. Separation of right and left digestive glands appears to be one of the first steps in the simultaneous and interdependent evolutionary processes of internal detorsion and external 'aeolidization' in nudibranchs.
The genus Sciarotricha gen. n. (Sciaridae) and the phylogeny of recent and fossil Sciaroidea (Diptera)

The phylogeny of the main groups of the Sciaroidea, including the fossil Antefungivoridae, Archizelmiridae, Mesosciophilidae, Pleciofungivoridae, Pleciomimidae, Protopleciidae and Bolitophilidae: Mangasinae, and an extant new taxon, was studied by parsimony analysis. Two cladistic analyses of seventy-eight morphological characters from adults were made. One analysis, with forty-one extant taxa in the ingroup and the other, with the addition of twelve fossil taxa, both produced two most parsimonious cladograms. The phylogenetic hypotheses obtained differed from each other, and in part also to a great extent from previous ones although most of the traditionally recognized groups appeared monophyletic, including the speciose Cecidomyiidae and Sciaridae. The Cecidomyiidae (fossil analysis) or the Keroplatidae-Ditomyiidae (extant analysis) appeared as the sister-group of the rest of the Sciaroidea. Following on from these analyses, we propose emending the current Sciaridae to include the following subfamilies: Archizelmirinae stat. n. , Rangomaraminae stat. n. , Sciarinae, Sciarosominae subfam. n. and Sciarotrichinae subfam. n. A new taxon from Namibia, Sciarotricha biloba gen. n. , sp. n. is described, and, according to the phylogenetic analysis, is placed in the Sciaridae (Sciarotrichinae). The sister-group of the Sciaridae as newly defined is the Mycetophilidae group, in the extant analysis including the Mycetophilidae, Manotidae, Lygistorrhinidae, Pterogymnus and Sciaropota , and in the fossil analysis even including the Mesosciophilidae and the Ohakunea group ( Ohakunea + Colonomyia ).
The effect of diflubenzuron and hexaflumuron on the last larval instars of the Mediterranean Flour Moth Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) under laboratory conditions

In insects, insect growth regulators (IGRs) regulate many developmental and physiological parameters. The effects of diflubenzuron and hexaflumuron wettable powder 25% and emulsifiable concentrate 10%, respectively, were investigated on the mediterranean flour moth. Different concentrations of them were applied topically on the last larval instars pronotum. The results indicated that the percentage of transformation of larvae to pupae, larvae to adult and pupae to adults reduced with increase in dosage; these parameters were recorded as 100% in control and 70, 30 and 43.45%, respectively for diflubenzuron and 73.33, 30 and 41.07%, respectively for hexaflumuron. Percentage of abnormal adults was 44.44% in 1,000 ppm of diflubenzuron and 66.67% in 316 ppm of hexaflumuron. Percentage in reduction of fecundity and fertility were counted 97.89 and 95.34% in the highest dosage of diflubenzuron, respectively, also 97.88 and 100% in 316 ppm of hexaflumuron, respectively. Consequently, they play an effective role in inhibiting cuticle formation and can reduce pest population.
Armillaria Root Rot Damage in Softwood Plantations in Ontario

Armillaria root rot. caused most likely by Armillaria obscura (Pers) Herink, killed 6-to 21-year-old white spruce, black spruce, jack pine and red pine saplings in each of 49 plantations examined in northern Ontario. Annual mortality in the four species over the last 2 to 6 years averaged 1.4%, 1.5%, 0.5% and 0.2%, respectively. In all but one of 25 white spruce and red pine plantations (43 to 58 years old) in eastern and southern Ontario. Armillaria root rot was associated with mortality. Accumulated mortality in white spruce and red pine (initially recorded in 1978) averaged 7.6% and 11.7%, respectively, as of 1986. Current annual mortality for all plantations ranged from 0% to 16%. Key words: root rot. Armillaria obscura, white spruce, black spruce, jack pine, red pine.
Postnatal growth of Brown hare (Lepus europaeus) in a South Italy rearing centre

Abstract The aim of this work is to describe the postnatal growth performance (period from birth to weaning) in Brown hare (Lepus europaeus) leverets in a rearing centre of Southern Italy. Three morphometric variables (body weight, hind foot length and ear length) were measured weekly from birth to weaning (at 21 days) in 78 leverets. Data were analysed by proc GLM (SAS) considering the effect of sex and birth period (1. January-February, 2. March-April, and 3. May-June). Birth period influenced significantly live weight at 14th day of life, lower in period 2 than in 3 (553 vs. 607 g; P≤0.05) and hind foot length at birth, shorter in period 1 compared to the period 2 and 3 (4.4 vs. 4.7 and 4.8 cm; P≤0.05), and at weaning, shorter in period 1 than in 3 (8.6 vs. 9.6 cm; P≤0.05). Leverets increased within 21 days their body weight 6.26, 6.76, and 6.97 fold in period 1, 2, and 3, respectively. Maximum growth speed (over 40g/d in all birth periods) was reached at the 3rd week. These results were consistent with the best performances described in literature for this species. Our data can be useful to evaluate the development of leverets in other rearing centres in Southern Italy. Furthermore, our data can be helpful for aging young Brown hares captured in the field, for example in those studies aimed to analyze the competition between Brown hare and endemic Italian hare (Lepus corsi in Mediterranean ecosystems. canus)
Assessing the Quality of Mass-Reared Codling Moths (Lepidoptera: Tortricidae) by Using Field Release-Recapture Tests

Following small-scale field releases of sterile, mass-reared codling moths, Cydia Pomonella (L.), in the spring of 1995, significantly higher numbers of adults originating from larvae that had been induced into diapause were recaptured in passive interception traps compared with standard (nondiapaused) colony moths reared under either constant or fluctuating temperatures. When releases were made in the summer, significantly more diapaused females were again recaptured and similar numbers of diapaused and fluctuating temperature-reared standard males were trapped. Our field data showed that both male and female codling moths dispersed farther as ambient temperatures increased. When standard and diapaused sterile codling moths were released into replicated l-ha plots under large-scale Sterile Insect Release program conditions in the summer and fall of 1996 and the spring of 1997, the proportion of recaptured diapaused males was significantly higher than for standard (nondiapaused) moths. This was true for recapture of males with passive interception, pheromone-baited, and virgin female-baited traps.
Water-level Management as a Tool for the Restoration of Shallow Lakes in the Netherlands

ABSTRACT Water-level fluctuations are among the major driving forces for shallow lake ecosystems. In the low-lying parts of the Netherlands, the water-level regime of lakes is strictly regulated. This is needed for reducing risks of flooding and economic purposes, including maximum agricultural benefit. The fixation of water levels has had a severe impact on the functioning of (semi-)aquatic ecosystems. We review the benefits of natural water-level fluctuations, considering the impacts on nutrient inputs, nutrient concentrations, phytoplankton development and turbidity. In particular, the mediating role of submersed and emergent vegetation and filter feeders is addressed. The present government policy, to allow more space for water, presents a major challenge for combining flood prevention measures and ecological restoration. Restoration of natural water-level regimes, which is likely to lead to enhancement of water quality and biodiversity, may occur in two ways: (1) expanding the critical limits between which the water level is allowed to fluctuate annually, and/or (2) incidental recessions of the water level. It is stressed that ecologically-based water-level regimes should be incorporated into the context of multiple use of lakes.
A nonpetide integrin antagonist can inhibit epithelial cell ingestion of Streptococcus pyogenes by blocking formation of integrin α5β1-fibronectin-M1 protein complexes

Abstract Streptococcus pyogenes can be efficiently internalized by a variety of human epithelial cells. β-lactam antibiotics, commonly used to treat S. pyogenes infections, do not readily permeate mammalian cells. There is growing evidence that the ability of streptococci to enter host cells contributes to the frequent failure of antibiotics to eradicate the organism from infected individuals. Recent studies have suggested that host cell entry requires the formation of a complex of a bacterial fibronectin (Fn) binding protein (e.g., M1 protein or protein F1/SfbI), human Fn, and the epithelial cell Fn receptor, integrin α5β1. We report here that a low molecular weight, nonpeptide antagonist of integrin α5β1, SJ755, can inhibit internalization of streptococci by primary human tonsillar epithelial cells and immortalized human epithelial (A549) cells, thus increasing the extent of bacterial killing by antibiotics. SJ755 blocked Fn binding by human tonsillar epithelial and A549 cells, suggesting that integrin α5β1 is the major Fn receptor expressed by both cell types. SJ755 did not affect Fn binding by purified M1 protein or M1+ bacteria. Purified M1 protein failed to associate with integrin α5β1 unless the integrin had been prebound by Fn. Also, SJ755 blocked formation of α5β1-Fn-M1 complexes in vitro. These results support the previous proposal that Fn functions as a molecular bridge between M1 protein and integrin α5β1. Furthermore, these results suggest that integrin antagonists may enhance the efficacy of antibiotics in treatment of S. pyogenes infections.
Effect of Egg and Larval Survival on Year-Class Strength of Lake Whitefish in Grand Traverse Bay, Lake Michigan

Abstract A study was conducted in Grand Traverse Bay, Lake Michigan, during 1983 and 1984 to identify factors that are important in determining year-class strength of lake whitefish Coregonus clupeaformis. The major determinants of year-class success were overwintering egg survival and the amount of food available to larval lake whitefish during the first 7 weeks of life, Egg mortality was related to the timing of ice cover, with an early cold winter producing the highest survival. Larval survival was affected by the abundance of available prey, i.e., copepod zooplankton between the sizes of 0.7 and 1A mm in total length. In 1983, when zooplankton of this size were abundant relative to larval fish density, high rates of growth and survival of lake whitefish ensued. In 1984, the prey-per-fish ratio declined greatly, and poor growth and low survival were observed. The dynamics of these early life stages appear to significantly influence both lake whitefish year-class strength and eventual recruitment in Gra.
Change in the Characteristics of Ca 2+ Signaling in Pancreatic Acinar Cells in Culture

In this study we studied Ca2+ responses to different stimuli in pancreatic acinar cells subjected to culture conditions. Cells were isolated from adult mice pancreas and were subjected to culture conditions along one week. Changes in intracellular free Ca2+ concentration were monitored by single cell fluorescence analysis of fura-2-loaded cells. Mitochondrial distribution was analyzed by confocal microscopy study of MitoTracker Green FM-loaded cells. Expression of amylase-containing cytoplasmic vesicles was analyzed by confocal microscopy study of cells transfected with a plasmid encoding amylase linked to a green fluorescent protein. Cell viability was analyzed employing the AlamarBlue test. Our results show that pancreatic cells in culture retain a mitochondrial network and amylase-positive vesicles. However, cells dropped their ability to mobilize Ca2+ in response to activation of cell membrane receptors. Ca2+ mobilization in response to the sarcoendoplasmic reticulum Ca2+-ATPase inhibitor thapsigargin was not altered. Cell viability was not affected by treatment with cholecystokinin, but was reduced in the presence of thapsigargin or hydrogen peroxide. We conclude that primary culture of pancreatic cells may be a suitable model to be used in studies where the involvement of mechanisms linked to the activation of specific cell membrane receptors is not required.
Fatty acid profile in varieties of chestnut fruits from Tenerife (Spain) Perfil de ácidos grasos en variedades de castañas procedentes de Tenerife (España)

Total fat and fatty acids (FA) were determined in chestnut samples belonging to 21 different chestnut varieties. Total saturated, monounsaturated, polyunsaturated acids and the relationships between them, such as oleic/linoleic and linoleic/linolenic, were calculated. The predominant FAs in the fat of chestnuts were linoleic acid (43.4 ± 4.1% of total FA), oleic acid (30.5 ± 4.8% of total FA), palmitic acid (14.7 ± 1.7% of total FA), and linolenic acid (6.76 ± 2.02% of total FA). These FA represent ≥ 90% of the total FA in all the varieties investigated. Considerable differences were observed in many FA and in their relationships according to the variety. The influence of the production zone only significantly affected the content of arachidic acid. Correlations between oleic acid with linoleic (r = −0.743) and linolenic (r = −0.593) acids were observed thereby indicating metabolic relationships between them. Se determinó el contenido de grasa total y de ácidos grasos en muestras de castañas pertenecientes a 21 variedades diferentes. Asimismo, se calcularon otros parámetros tales como ácidos grasos saturados, monoinsaturados, poliinsaturados, y relaciones oleico/linoleico y linoleico/linolénico. Los ácidos grasos predominantes en la grasa de castañas fueron linoleico (43,4 ± 4,1% del total de ácidos grasos), oleico (30,5 ± 4,8% del total de ácidos grasos), palmítico (14,7 ± 1,7% del total de ácidos grasos) y linolénico (6,76 ± 2,02% del total de ácidos grasos). Estos ácidos grasos representan más del 90% de los ácidos grasos totales en todas las variedades investigadas. Se observaron diferencias en los contenidos de muchos ácidos grasos y sus relaciones en función de la variedad. El área de producción sólo afectó de forma significativa el contenido de ácido araquídico. Se establecieron algunas correlaciones significativas entre los ácidos grasos, destacando las existentes entre el ácido oleico con el ácido linoleico (r=−0.743) y con el ácido linolénico (r=−0.593), lo que pone de manifiesto las relaciones entre ellos.