Miracle-dz/UniFAR-FTUs huggingface dataset:
Reply - Effects of adventitious roots on age determination in balsam fir regeneration

In many Canadian boreal forests, balsam fir (Abies balsamea (L.) Mill. ) seedlings established under closed canopy generally develop adventitious roots. Adventitious roots induce the formation of a reverse taper, i.e., a reduction of the diameter and of the number of growth rings towards the true collar (hypocotyl region). Consequently, ring count at any level of the trunk underestimates the true age of firs, and we recommend a reassessment of balsam fir dynamics inferred from studies based on ages estimated by ring count. Recently, Kneeshaw and Claveau (D.D. Kneeshaw and Y. Claveau. 2001. Can. J. For. Res. 31: 1292-1295) presented data from a subsample of fir seedlings to demonstrate that ring count is an accurate aging technique for most fir regeneration. A careful examination of the methodology, data, and samples presented suggests that true collars were not precisely located. We also present data collected on seedlings sampled in the same study area as Kneeshaw and Claveau. Most of the seedlings (57 of.
The control of proline consumption by abscisic acid during osmotic stress recovery of canola leaf discs

Some aspects of the function of abscisic acid (ABA) in the control of proline (PRO) metabolism in canola leaf discs (CLD) subjected in vitro to consecutive hyper-osmotic (stress) and hypo-osmotic (recovery) treatments have been investigated. PRO accumulation in response to stress conditions relies on both stimulation of its synthesis via enhancement of transcription of the gene and activity of Δ 1 -pyrroline-5-car-boxylate synthetase (P5CS) and inhibition of its degradation via inactivation of PRO dehydrogenase (PDH). These changes were partly reversed under recovery conditions. Thus both PDH mRNA and PDH activity increased while P5CS mRNA decreased. Surprisingly P5CS activity remained high even after a 20-h period of rehydration. Exogenously supplied ABA at recovery inhibited net PRO consumption and this could be associated with downregulation of PDH gene expression and PDH activity. Under these conditions ABA hardly upregulated P5CS gene expression while P5CS activity first transiently decreased and then reached a value close to that found under stressing conditions. Experiments with CLD supplied with either methionine sulphoximine or gabaculine, brought preliminary evidence for a significant synthesis of PRO from glutamate during recovery that replenished the proline pool(s) and provoked a negative effect on the net rate of PRO consumption. Consequently, it is suggested that the availability of both PRO precursors and ABA could be determinant in the control of the amount of residual PRO present in CLD after the period of recovery. This level also seemed to depend on the amount of P5CS transcripts induced under stress conditions. However, the results obtained with turgid leaf discs treated with ABA-indicate that the ABA status of the tissues, necessary for inducing the proline response, is not sufficient to determine their PRO content because it remained relatively low despite the stimulation of PSCS expression and P5CS activity.
Anti-predator response of naive and experienced common bully to chemical alarm cues

Histological analysis of the skin of common bully Gobiomorphus cotidianus, a New Zealand native eleotrid fish, revealed the presence of club cells in the epidermis. Epidermal club cells are frequently associated with the production of alarm substance (Schreckstoff). The behavioural responses of perch-naive and perch-experienced common bullies to either conspecific skin extract or chemical cues from an introduced predator, perch Perca fluviatilis, were then examined. Both perch-naive and perch-experienced common bullies exhibited a behavioural response when exposed to conspecific skin extract, indicating the probable presence of an alarm substance. In contrast, only perch-experienced common bullies recognized and exhibited a subsequent behavioural response to the odour of perch. This study is the first to document the presence of epidermal club cells and a behavioural response to a conspecific chemical alarm signal for fishes in the Eleotridae. The results indicate that common bully can learn to recognize perch odour as a threat, and that this ability may be a result of previous predator labelling involving a conspecific alarm substance.
Ferrous iron transport mutants in Escherichia coli K12

A ferrous iron transport system in Escherichia coli is described. Mutants in this transport system were isolated using the antibiotic streptonigrin. The gene locus feo (for ferrous iron transport) was mapped near pncA at 38.5 min on the genetic map of E. coli K12. The transport of ferrous iron was regulated by fur as the siderophore transport systems.
CONSTRUCTING CHICAGO

A section for the review of books is a regular feature of Landscape Journal. The opinions and ideas expressed in the reviews are those of the reviewers and do not necessarily depict the views of the Journal’s editors or the Council of Educators in Landscape Architecture. Suggestions for books to be reviewed are always welcome, as are comments regarding the reviews published. All correspondence should be sent to either of the following Book Review editors:
A Minimally Invasive Technique to Monitor Valve-Movement Behavior in Bivalves

A real time, minimally invasive method to observe valve movement of bivalves using proximity sensors and a personal computer has been developed. The method is being evaluated as a tool to assess both episodic toxicity events and ambient toxicity. The method described minimizes contact with the animal to the anchoring of one valve and the placement of a small aluminum foil disk on the other valve, and allows the measurement of the distance that a clam's valves are open. Using proximity sensors and an aluminum foil target, valve movements of the Asiatic clam, Corbicula fluminea were measured and digitally recorded using a data acquisition board and a personal computer. One advantage of this method is its use of readily available stock electronics. In its final form, we envision an in situ biological monitoring system using C. fluminea deployed in aquatic systems in association with automated physical/chemical monitoring systems like those found at USGS gauging stations. A tool such as this could be used as .
Production, scavenging and toxicity of hydrogen peroxide in the green seaweed Ulva rigida

Some aspects of hydrogen peroxide (H2O2) production, scavenging and toxicity in Ulva rigida (Chlorophyta) have been investigated. The seaweed produced H2O2 in light and excretion increased exponentially with increasing light up to 800 μmol photons m-2 s-1 where the excretion rate was 330 μmol (kg Chl a)-1s-1. This corresponded to a concentration of 4 μMH2O2 in the experimental medium after 30 min (density of seaweed: 9·2 kg fresh weight m-3). At 1200 μmol photons m-2 s-1, the excretion rate decreased to 190 μmol (kg Chl a)-1 s-1. At 600 μmol photons m-2 s-1, the excretion caused a concentration of 1·8 μM H2O2 in the experimental seawater; after a further 2 h the concentration decreased to a steady level of c. 0·8 μM. The enzymatic degradation of H2O2 is suggested to be primarily through the activity of ascorbate peroxidase (62 mmol H2O2 (kg Chl a)-1 s-1) since no catalase activity was detected. The H2O2 levels in U. rigida are reduced by diffusion through the plasmalemma. Addition of 1 mM H2O2 caused an 8.
Role of the sandprawn Callichirus kraussi as an ecosystem engineer in a South African temporarily open/closed estuary

The role of the sandprawn Callichirus kraussi as an ecosystem engineer was experimentally assessed using caging experiments over a four-month period in 2010 in the temporarily open/closed Kasouga Estuary on the south-eastern coast of South Africa. The sandprawn contributed to a significant increase in bioturbation, associated with a decline in microphytobenthic algal concentrations which coincided with a significant decrease in the abundance of the gastropod Nassarius kraussianus. The presence of the sandprawn did not contribute to a significant decline in sediment organic content, or to the abundance, biomass and species composition of the infauna, which comprised mainly amphipods, isopods and polychaetes. Nor did it contribute to a change in the macrofaunal community structure. The absence of any significant differences between the various treatments appears to reflect the low densities of sandprawns in the estuary during the study period.
Late Gothic Altarpieces as Sources of Information on Medieval Wood Use: A Dendrochronological and Art Historical Survey

Wooden altarpieces are important features of European medieval material culture, especially of the Late Gothic Fine Arts from the 15th and 16th century. Many of them were carved in the Brabantine towns of Antwerp, Brussels and Mechelen in present-day Belgium. Although they were highly esteemed and exported all over Europe, little is known about their production process. In order to understand the context of the creation of the altarpieces, a detailed analysis of the wood has been completed to supplement and test historical documentation and art historical approaches. Tree-ring patterns and anatomical features of 209 wooden sculptures from collections of different museums were analyzed. Tree-ring analysis proved the 15th –16th century origin of the sculptures but also allowed a detailed technical characterization of the carversʼ basic material. The striking uniformity of the grain and the sawing pattern revealed that medieval woodcarvers preferred quarter sawn oak lumber, imported from the Baltic area. Stylistic and iconographic hypotheses concerning the current setting of several altarpieces could be founded, based on the wood anatomical and dendrochronological observations. Intensive collaboration between wood biologists and art historians proved to be essential in order to reconstruct the creation process of carved wooden altarpieces.
Studies on the population structure of zooplankton in the Kotmale reservoir

Planlrto~i samples were collected fromKotmale reservoir, at approxi- mately monthly intervals from August 1990 to August 1991. Investigations werc foc~ised on species composition, seasonal variation, vertical and horizontal distrjbution ancl the size class distribution in the population structure of' zooplanlcton. Two species of cyclopoids, two species of calanoids, nine species of claclocerans ancl sixteen species of rotifers were recorded. Among these, the most abundant species during the study period wereMesocyclops sp,Plzyllodiaptonrus UIL,LCL~, Ccriodc~phl~ia col.nc~ta, Kcratella tl-opica, Filina lo~zgiseta, B~-nchio~z~rs cnrrdntzrs and TJ-icocer-cc' sinrilis. A location at the deepest region of the reservoir closer to the dam was selectei as a representative station to investigate the vertical distribution of zooplanlcton. At this location, the vertical distribution patterns of all the zooplanlcton werc almost similar throughout the year. As this location is situated at the down stream region of the river, it was expected to contain most of the zooplanlrton of the reservoir. The horizontal distribution of zooplankton dicl not show much variation. The nauplii stages and cyclopoids showed highest abundance in the population of zooplanlrton. However,during most of the months, the adult stages of calanoids and cladocerans were highly
Untersuchung von drei Grundwasserwerken auf Vorkommen von Acanthamoeben, Naeglerien und anderen freilebenden Amöben

Die quantitative und qualitative Erfassung der Amobenvorkommen in drei mit angereichertem Grundwasser gespeisten Trinkwasseraufbereitungsanlagen lies eine effektive Beseitigung der zahlreichen im Rohwasser anzutreffenden Amoben- und zahlreicher weiterer Protozoenarten im Verlauf der Aufbereitung erkennen, so das sie im Reinwasser nur noch vereinzelt gefunden wurden. Acanthamoeben und Naeglerien wurden in keiner der Anlagen im Reinwasser nachgewiesen, obwohl diese Gattungen mit thermophilen und dementsprechend potentiell pathogenen Stammen relativ haufig aus dem Rohwasser angezuchtet und isoliert wurden. Die wiederholte Beobachtung der intrazellularen Vermehrung von Bakterien der Gattung Cytophaga in Acanthamoeben bzw. Vannellen unterstreicht die Bedeutung der Amoben als Wirtszellen fur verschiedene Bakterienarten wie Legionellen, Listerien, Pseudomonaden und anderen Keimen. Aus fruheren Beobachtungen im Zusammenhang mit dem Acanthamoeba-Legionella-Modell kann abgeleitet werden, das die in Trophozoiten und in Zysten eingeschlossenen vitalen Keime auf diese Weise insbesondere gegen die gebrauchlichen Chlor- und anderen Biocidkonzentrationen geschutzt sind. Prevalence of Acanthamoebae, Naegleriae and Other Free-living Amoebae in the Course of Water Treatment in Three Well Waterworks Numerous species of free-living amoebae and other protozoa had been observed in the raw water of three representative waterworks with enriched well water. They were eliminated most effectively during the water treatment procedure. Acanthamoebae and Naegleriae including thermophilic strains of these genera could not be identified in any of the clear water samples. Acanthamoebae and Vannellae isolated from different samples exhibited repeatedly intracellular infections with bacteria of the genus Cytophaga. Their role as possible hosts of different pathogenic and non pathogenic bacteria like Legionella sp. , Listeria sp. , and Pseudomonas sp. is confirmed by this observation. As known from earlier findings in connection with the Acanthamoeba-Legionella model, it can be assumed, that bacteria multiplying in trophozoites or being enclosed in cysts are protected against high concentrations of chlorine and other biocides.
Histologic Evaluation of the Safety of Copper Sulfate to Channel Catfish

Abstract A histological study was done to evaluate the effect of waterborne exposures of copper sulfate (CuSO4) on channel catfish Ictalurus punctatus. Channel catfish were exposed daily for 11 consecutive days to three concentrations of CuSO4 representing one, three, and five times the recommended therapeutic level based on the total alkalinity. Fish were treated with CuSO4 in water flow-through tanks at a flow rate of 0.633 L/min. More than half the Cu was flushed in 1 h, which is similar to the elimination rates in ponds (due to the rapid uptake of Cu by aquatic plants or algae and the binding to organic and inorganic material). All fish were clinically normal and no fish died during the experiment. All examined tissues were grossly and histologically normal as well. The absence of histological lesions was attributed to the brief daily exposure to copper and to moderate total alkalinity and total hardness of the well water used. The results of this study suggest that CuSO4 is safe for channel catfish p.
Taxonomic notes on the New Zealand flora: recognition of two subspecies in Dicksonia lanata

Dicksonia lanata subsp. lanata and D. lanata subsp. hispida are raised from varietal rank and recognised here as separate subspecies. The former is distinguished primarily by the lack of a trunk and the presence of dense clusters of woolly, chestnut brown hairs at costa junctions on the underside of the laminae; the latter has short arborescent trunks, and longer, rigid, red–brown hairs among shorter, fine, pale brown hairs on the underside of the costae and pinna midribs. Previous genetic analyses of both subspecies support this distinction. The rank of subspecies rather than species has been chosen because the two groups are allopatric and, as far as is known, not reciprocally monophyletic. Subspecies hispida occurs from North Cape to the northern Kaipara Harbour and Great Barrier Island, and subsp. lanata from Thames to the Ruahine Ranges and on the north and west coasts of the South Island. Plants from the southern Coromandel Peninsula are of somewhat equivocal status but are treated here as belonging to subsp. lanata; they are similar to subsp. lanata in lacking a trunk, but have hair characters that in most cases do not clearly correspond to those of either subspecies. This article is a contribution towards clarifying the taxonomic and nomenclatural status of New Zealand plants for the plant names database (Ngā Tipu Aotearoa) and the electronic Flora of New Zealand.
Carbonate build-ups in lacustrine, hydrothermal and fluvial settings: comparing depositional geometry, fabric types and geochemical signature

Abstract Carbonate build-ups in lakes, hydrothermal and fluvial settings are characterized by distinctive geometry, spatial distribution, fabrics and geochemical signature but also by some comparable features. Lake margin bioherms form continuous belts for hundreds of metres to kilometres, subparallel to shorelines. Sublacustrine spring mounds are spaced at hundreds of metres to kilometres and aligned along faults. Hydrothermal travertine mounds and aprons with planar clinoforms or terraced slopes are controlled by faults, thermal water discharge and substrate topography. Fluvial tufa barrages, cascades and terraced slopes are controlled by climate, vegetation and substrate gradient. The wide spectrum of carbonate microfabrics ranges from clotted peloidal micrite and laminated boundstone to crystalline dendrite cementstone. Non-marine carbonate microfabrics cannot be linked to specific depositional environments, and are not deterministic proxies for the interpretation of build-up architecture. Microfabric associations can be indicative, but not exclusive, of specific depositional environments and geometry. Stable isotope geochemistry is a useful tool to distinguish between hydrothermal, karstic freshwater and evaporative lake carbonates. Carbonate precipitation results from a continuum of abiotic and biologically influenced/induced processes in settings where carbonate supersaturation is largely driven by physico-chemical mechanisms and microbial biofilms, even if acting as passive low-energy surface sites for nucleation, are widely present.
Temperature Effects on Rice at Elevated CO2 Concentration

The continuing increase in atmospheric carbon dioxide concentration ([CO 2 ]) and projections of possible future increases in global air temperatures have stimulated interest in the effects of these climate variables on agriculturally important food crops. This study was conducted to determine the effects of [CO 2 ] and temperature on rice (Oryza sativa L., cv. IR-30)
Evolutionary Strategies and Developmental Constraints in the Cellular Slime Molds

Over the last 30 years there has been a large accumulation of information on numerous aspects of the development and other features of the life cycle of cellular slime molds. These curious organisms arise by the aggregation of single and previously solitary amoebae to form small, multicellular structures consisting ultimately of a stalk supporting one or more spore masses or sori. Because there are relatively few known species (ca. 50) and because they are so amenable to study in the laboratory, we have acquired considerable knowledge of this microcosm of the living world. Here I would like to examine the microcosm and try to understand it in terms of what might have been the evolutionary strategies that molded the various permutations of their life histories, and how these changes might have been constrained by developmental and mechanical problems. These questions have been asked of higher organisms and it is an obvious and well-accepted notion that a mammal, for instance, cannot indulge in just any kind of variation, but is strictly limited by the elaborate sequence of developmental steps which permit a limited number of genetic changes; all others will be lethal. In fact, the more elaborate the development, the greater are the constraints on developmental change. Furthermore, it is for this reason that most genetic variation affects changes in the later stages of development rather than in early ones. After all, a mutation in a gene affecting astrulation has a high probability of being lethal which is not true for one affecting eye or hair color. It is also well known and well understood in vertebrates that there is nevertheless a way of accomplishing major change. This is by heterochrony; by changing the timing of developmental events so that, for instance, some developmental processes will occur at a different time relative to others in a descendant (de Beer 1940; Bonner 1965; Gould 1977). The changes produced by heterochrony can be profound, such as larval forms producing mature eggs and sperm, or the prolongation of development to produce the extraordinary large brain in man. Such major changes are possible not only because the basic developmental plan of the organism will not be altered, but also, it is assumed, because the amount of genetic change needed to produce the alteration in timing could be relatively small. One of the important functions of regulatory genes must be to control the timing of the different elements of development.
Genetic Diversity of Chinese Cultivated Soybean Revealed by SSR Markers

China is the center of origin of soybean [Glycine max (L.) Merr. ] and is therefore expected to represent a primary source of germplasm for this crop. Genetic diversity assessments among Chinese soybean accessions should provide useful information for local and international soybean researchers to more effectively utilize this material. A sample of 129 accessions were selected to represent phenotypic variability for 14 agronomic and morphological traits in the Chinese soybean collection. These accessions were analyzed with 60 mapped simple sequence repeats (SSRs) to determine the genetic diversity represented. In total, 732 alleles were detected (12.2 alleles per locus) and the polymorphic information content (PIC) among accessions varied from 0.5 to 0.92 with a mean of 0.78. Pairwise coefficients of genetic distance among all accessions ranged from 0.05 to 0.91 (mean 0.23). Unweighted pair-group method arithmetic average (UPGMA) analysis showed that the accessions formed five major clusters; two contained primarily Northern ecotypes, one contained primarily Yellow River Valley ecotypes, and one contained Southern ecotypes. The fifth cluster contained a mixture of Northern and Yellow River Valley ecotypes. Accessions from the lower regions of the Yellow River Valley possessed the greatest allelic richness, had the lowest pairwise genetic diversity estimates, and were dispersed throughout the five clusters, suggesting that the Yellow River Valley may be center of diversity for Chinese cultivated soybean. The results indicated that stratified sampling based on seven primary ecotypes may represent an optimal strategy for assembling a representative core collection of Chinese soybean.