bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of agricultural intensification on Skylarks(Alauda arvensis): Evidence from monitoring studies in Great Britain
Authors: Chamberlain D E , Siriwardena G M
Published: April 2011

Declines in a number of farmland bird species in northern Europe have been linked to agricultural intensification. In this paper, we review the evidence for the effects of agricultural intensification on farmland bird populations using monitoring studies on a single well-studied species, the Eurasian Skylark (Alauda arvensis). Between 1970 and 1998, the Skylark population declined by 44% and this decline was greatest on farmland compared to upland or coastal habitats, yet during that time, reproductive performance per individual nesting attempt improved significantly. Skylarks consistently prefer relatively sparse (spring cereals) or structurally complex (fallow "set-aside"') crops, particularly late in the breeding season when crops that are too tall or dense are abandoned. Outside the breeding season, cereal stubble is the most preferred foraging habitat. Intensification has been characterized by decreases in preferred crops (spring cereals and cereal stubble) and an increase in unfavourable habitats (winter cereals, oilseed rape, and intensively managed or grazed grass). Reduction in the number of breeding attempts due to rapid sward development of winter cereals and the lack of suitable alternative habitats is likely to have been an important factor in the Skylark decline. The decline may also have been driven by decreases in survival outside the breeding season. Management regimes that include spring cereals, cereal stubble, and low-intensity grazing are likely to increase Skylark abundance and will benefit a number of other farmland birds. This review highlights the great value of large-scale monitoring schemes in understanding population declines. However, the factors affecting the post-fledging survival of Skylarks and the effects of crop diversity on Skylark abundance remain to be resolved. Key words: agricultural management, cereals, habitat diversity, intensification, population trend, reproductive performance.
Arsenic in groundwater in the Bengal Delta Plain: slow poisoning in Bangladesh
Authors: Mukherjee A B , Bhattacharya P
Published: April 2011

The purpose of this paper is to provide an overview of the problems concerning the widespread occurrences of arsenic in groundwater in Bangladesh, a land with enormous resources of precipitation, surface water, and groundwater. Because of the potential risk of microbiological contamination in the surface water, groundwater was relied on as an alternate source of drinking water. Exploitation of groundwater has increased dramatically in Bangladesh since the 1960s to provide safe water for drinking and to sustain wetland agriculture. The presence of arsenic in the groundwater at elevated concentrations has raised a serious threat to public health in the region. Nearly 6075 million people inhabiting a large geographical area are at potential risk of arsenic exposure, and several thousands have already been affected by chronic arsenicosis. The source of arsenic in groundwater is geogenic and restricted within the Holocene sedimentary aquifers. Mobilization of arsenic from the alluvial aquifers is primarily effected through a mechanism of reductive dissolution of the iron oxyhydroxides within the sediments, rather than by the oxidation of pyrite, as has been hypothesized by other workers. The problem is further accentuated by the fact that arsenic is also found at elevated concentrations in vegetables and rice grown in the areas where high-arsenic groundwater is used for irrigation. Dietary habits among the population are also an important pathway for arsenic ingestion. Studies are in progress at national as well as international levels to alleviate the arsenic crisis in Bangladesh. Besides the identification of arsenic-free tubewells in the affected areas for drinking purposes, purification of groundwater at household level by low-cost arsenic removal techniques is suggested. Rehabilitation of the patients with chronic arsenicosis and arsenic education programs for rural communities must be addressed urgently by the government of Bangladesh. Key words: arsenic, groundwater, chemistry, redox, causes, effects, Bangladesh.
Chromium in the Canadian environment
Authors: Nriagu Jerome O. , Kabir Abdul
Published: April 2011

The widening use of chromium and its compounds by local industries has led to a growing concern about the effects of chromium contamination on the Canadian environment. This report summarizes the data on Canadian sources and the concentrations of chromium in air, water, sediments, soil, terrestrial wildlife and aquatic biota. It reviews what little is currently known about the cycling of chromium in Canadian ecoystems, and the need for measuring Cr(III) and Cr(VI) rather than total Cr in the environmental media is emphasized. The potential effects of elevated levels of chromium on plants, soil microorganisms, wildlife, and aquatic biota are discussed. The human health effects are not covered. The conclusion is reached that chromium pollution has become a threat to Canadian ecosystems, especially at the local scale where the ambient chromium concentrations in some surface waters, sediments, and soils are now close to or above the toxicity threshold for a number of the more sensistive organisms.Key words: chromium pollution, chromium toxicity, chromium chemistry, chromium emission, bioaccumulation of chromium.
The ecotoxicology of coplanar polychlorinated biphenyls
Authors: Metcalfe Christopher D. , Haffner G. Douglas
Published: April 2011

Polychlorinated biphenyls (PCBs) have been recognized for over 25 years as global environmental contaminants. However, many PCB congeners may be relatively harmless, while a small group of PCB congeners are highly toxic to biota. The toxic coplanar PCB congeners are chlorinated at meta positions and at one or none of the ortho positions on the biphenyl ring, thus resembling 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in molecular configuration. In vitro and in vivo toxicity tests with rodents, fish, and birds have shown that the coplanar PCB congener 126 is almost as toxic as TCDD. Several coplanar PCBs (e.g., 77, 126, 105, 118) are present in biota at parts per billion concentrations, which is orders of magnitude higher than concentrations of TCDD. Thus, coplanar PCBs may account for over 95% of the dioxinlike toxic activity affecting biota, such as fish-eating birds in the Great Lakes. There is some evidence that the toxicokinetics of coplanar PCBs in organisms differs from that of other PCB homologues. If coplanar PCBs are more persistent than their homologues, they could become enriched in biota as they pass up through the food chain (i.e., trophic enrichment), or as overall PCB levels decline with time (i.e., temporal enrichment). Overall, the available data do not support the concept of trophic or temporal enrichment in the environment.Key words: polychlorinated biphenyls, coplanar, toxic equivalents, kinetics, mixed function oxidase, 7-ethoxyresorufin-O-deethylase.
Considerations for establishing relationships between ambient ozone (O3) and adverse crop response
Authors: Krupa S V , Kickert R N
Published: April 2011

Exposures to the all pervasive ambient ozone (O3) can and has resulted in visible foliar injury and (or) reduction of crop growth and yield. However, most of our knowledge regarding the latter effect is derived from above ambient, artificial O3 fumigations in field exposure chambers. In the most recent years, such methodologies have been the subject of much criticism. Further, in such studies, efforts to establish cause-effect relationships have mainly relied on the use of single-point, season-end statistical descriptors of the O3 exposure and crop yield measurements. Such models do not consider the time lag in feedback and the extent of plant stress, repair, or compensation that regulate the final crop biomass in response to highly variable ambient O3 exposures in time and space. Therefore, no single such model has performed consistently. In this paper we provide explanations for the problem. Further, we discuss the need to couple atmospheric properties that are conducive for the transfer of O3 onto plant canopies and crop properties that promote O3 uptake (absorbed dose), a prerequisite to the observed effect. Additional discussion is directed to considerations for performing experiments in chamberless, ambient environments and for the use of multipoint exposure-response models. Issues are highlighted as to the difficulties and uncertainties associated with the available data in establishing ambient air quality regulations to protect crops.
An evaluation of environmental and other factors in some recent marine mammal mortalities in Europe: implications for conservation and management
Authors: Simmonds M P , Mayer S J
Published: April 2011

Major mortality events in marine mammal populations have become a feature of recent years and their causes have been much debated. Here we review the investigations that have been made to date into the 1988 seal epizootic in the North Sea region, the 1990-1992 striped dolphin epizootic in the Mediterranean Sea, and the recent spate of sperm whale strandings in the northeastern Atlantic. We consider the evidence for multifactorial causality in these events and the problems inherent in determining causes. The patterns of disease seen in both the phocine distemper virus and the dolphin morbillivirus precipitated events suggest complex underlying aetiologies with changes in hosts and (or) marine environment, with significant implications for the conservation and management of marine mammal populations. The sperm whale strandings are used to illustrate the difficulty of investigating or even detecting such events in marine mammal populations.
Current needs in environmental risk management
Authors: Hrudey S E
Published: April 2011

Risk assessment and management have become central to many health and environmental issues in recent years. Despite high expectations for the applications of science to identify and manage risks, many of these issues remain controversial. Some of the foundations of risk assessment and management are explored and needs for improvement are identified. Inputs from models, data, and uncertainty analyses are reviewed and goals for risk assessment, management, and communication are considered. Ultimately a better understanding of the strengths and limitations of these processes, primarily by the specialists and decision makers, is a prerequisite to more effective involvement of affected stakeholders in risk management. Unless some better basic understanding is achieved, public expectations and demands for risk management are likely to remain unachievable.
Biological invasions: are they dependent on disturbance?
Authors: Lozon J D , MacIsaac H J
Published: April 2011

We utilize literature surveys to examine the relationship between establishment of exotic species and human or natural disturbances of ecosystems. Of the 133 papers published in 10 ecological journals between 1993 and 1995, 63 reported on field studies involving 299 and 103 successful, nonredundant plant and animal introductions, respectively. Invasions of terrestrial ecosystems dominated (>>97%) the surveyed literature. Disturbance was associated with establishment of exotic species in 56% of these studies, though its importance differed among papers describing plants (68%) and animals (28%). Plants species (86%) were significantly more dependent on disturbance for establishment than were animals (12%). However, animals and plants that were dependent on disturbance for establishment were almost equally dependent (58 versus 68%) on it for range expansion. In a second survey, 402 plant and 103 animal taxa were identified that explicitly linked establishment of exotic species to disturbance. Human activities were attributed with establishment of species in 97 and 57% of these cases, respectively. Common mechanisms associated with establishment of exotic animals included ballast water discharge, intentional releases, and residential development. Establishment of exotic plants was associated with animal activities (e.g., grazing, seed introduction), soil disturbance, forestry, fire, agriculture, and human activities. In contrast to invasions theory, our survey indicates that the association between establishment and spread of exotic species and disturbance ought not be assumed a priori. Some animals repeatedly invade new habitats once geographic barriers are circumvented, indicating that communities may be more receptive to exotic species than previously acknowledged. By contrast, introduced plants established most often in disturbed habitats.
A decade of forest tree monitoring in Canada: evidence of air pollution effects
Authors: McLaughlin Dave
Published: April 2011

In Canada, the eastern tolerant hardwood forest is potentially at risk from air pollution. Surveys indicate that, overall, the condition of hardwood forests has either not changed or has marginally improved. However, stands growing on shallow, poorly buffered soils have a higher frequency and severity of decline symptoms, and some of these stands have continued to decline, in contrast to the general trend. In Ontario on the most sensitive sites (<6 mequiv. exchangeable bases/100 g), decline symptoms increased coinciding with a decrease in B horizon pH and base saturation and with an exchangeable Al increase. On these sites the chemical analysis of foliage, root, xylem, and soils indicate that nutrient deficiencies, nutrient imbalances, or metal/nutrient antagonism are related to stand decline. There is a consistent spatial relationship between white birch decline in the Bay of Fundy area and acidic sea fog. Acid fog injures and leaches foliage and hastens soil acidification, leaving the stands weakened and making them more sensitive to stress, particularly drought. Some recent studies suggest that forest growth rates are declining and that the relationship with climate has deteriorated, implying that the forests are responding to a regional, nonclimatic, nonpathogenic stress. This could be a response to altered forest nutrient cycling associated with acidic deposition and chronic O3exposure. A study of sugar maple in Ontario estimated that after the mid-1960s growth has declined between 0.66 and 0.96 m3·ha-1·year-1, and that the decline was greatest on poorly buffered soils. Without enhanced forest management and more stringent air pollution regulations, the sustainability of forest productivity in Eastern Canada is likely to be difficult because of air pollution and soil fertility losses.Key words: dendroecology, acid deposition, ozone, forest decline, sugar maple, climate change.
Scaling up to understand British Columbia's boreal mixedwoods
Authors: Andison D W , Kimmins J P
Published: April 2011

The perception of, and interest in, the boreal mixedwood forests has changed dramatically over the last two decades. This is particularly true of British Columbia, as shown by the recent wave of biodiversity-related legislation. The static notion of the boreal mixedwoods as a collection of low-yield, competition-prone, mixed-species stands is being replaced by that of a diverse, shifting landscape mosaic containing a wide array of resources. As this change in perception continues, it will be necessary to formulate a new conceptual framework within which to manage the boreal mixedwoods to meet a much broader range of objectives. This review argues that the traditional stand-level model of mixedwood management is inadequate as a management paradigm for the future. A more holistic view of mixedwood management is required that considers processes at all scales, and takes into account the wide temporal and spatial variability that occurs naturally in this type of disturbance-driven forest.Key words: boreal mixedwoods, landscape-level, succession, disturbance, variability.
Managing to sustain vertebrate richness in forests of the Pacific Northwest: relationships within stands
Authors: Bunnell F L , Kremsater L L , Wind E
Published: April 2011

Many regions confront potentially competing goals: sustaining biological diversity and extracting wood products from forests rich in biological diversity. Forests of the Pacific Northwest are particularly rich in vertebrates. Because little is known of many species, management tactics to sustain vertebrate richness must employ interim surrogates that credibly reflect responses of groups of vertebrates. These tactics should focus on elements of the forest, commonly altered by forest practices, to which groups of species are closely linked. We identify five such elements for forests of the Pacific Northwest: dead and dying trees, downed wood, shrubs, hardwoods (broadleaved, deciduoustrees), and riparian areas. Most forest-dwelling vertebrates in the Pacific Northwest, including those designated "at risk", require one or more of these forest elements. Late-successional forests represent particular mixes of these elements. Each element can be altered in ways that benefit or harm specific groups of species. Any management decision, including taking no action at all, favours some species while disadvantaging others. We report the proportions of the vertebrate fauna associated with the five forest elements, plus early- and late-successional stages for a range of forest types. The nature of relationships with each forest element is quantified by biologically appropriate measurements (e.g., decay state, tree species, snag density, and tree size for cavity sites). Impacts of current practices are summarized and tactics appropriate for maintaining vertebrates are described. Responses of organisms other than vertebrates are noted.

Key words: forest practices, Pacific Northwest, vertebrate richness.
Light and electron microscopy of the spermogonial stage of Gymnoconia peckiana, one of the causes of orange rust of Rubus
Authors: Mims Charles W. , Richardson Elizabeth A.
Published: April 2011

Hyphae of Gymnoconia peckiana (Howe in Peck) Trotter spread from infected Rubus argutus Link. stems into leaf primordia where they proliferated in an intercellular fashion as leaves differentiated. Hyphae were septate, and each compartment appeared to contain a single nucleus. Hyphae gave rise to numerous haustoria that resembled the monokaryotic haustoria of other rust fungi. Hyphae located immediately adjacent to the upper and lower leaf epidermis gave rise to spermogonial initials. Each initial consisted of a small group of tightly packed hyphae that developed in an intercellular space adjacent to the epidermis. As an initial enlarged, the proliferating hyphae pushed their way between, as well as into, epidermal cells. Invaded epidermal cells soon died. A layer of spermatiophores then developed within each young spermogonium and appeared to push the epidermal cell wall material and leaf cuticle covering the spermogonium out from the leaf surface. Once mature, spermatiophores gave rise to a succession of uninucleate spermatia that emerged from the tip of each spermatiophore. Spermatia initially accumulated beneath the layer of epidermal cell wall material and cuticle that covered the developing spermogonium and appeared to push this layer further out from the leaf surface until it ruptured. A few receptive hyphae were observed in mature spermogonia.
Pollination effects on patterns of ovule fate in Hesperis matronalis (Brassicaceae)
Authors: Susko David J. , Clubb Michelle
Published: April 2011

We examined ovule positional effects on patterns of ovule development within linear fruits of the invasive weed, dame’s rocket, Hesperis matronalis L. Fruits were collected from two sites in southwestern Ontario, Canada. The majority of ovules within fruits were aborted early in development. Emergent patterns of ovule abortion and seed maturation within fruits were nonrandom and dependent on ovule position. The probability of seed maturation within individual fruits decreased significantly from basal to distal ends, suggesting an intrafruit resource gradient. Self-pollinated flowers at one site produced fruits with a similar pattern of seed maturation as was found for open-pollinated plants. However, cross-pollinated flowers produced fruits in which the pattern of seed maturation was reversed; more seeds were matured at the distal ends rather than the basal ends of fruits, indicative of a fertilization gradient. Analysis of pollen-tube growth showed that ovule failure may not be attributed to pollen limitation. For seeds produced via hand-pollinations, we found no relationship between seed mass and seedling biomass, although seeds from self-pollinations germinated more readily than did seeds from cross-pollinations. While patterns of ovule fate in H. matronalis can be manipulated by pollen source, the effects of such patterns on plant fitness are yet to be determined.
Exposure to aphids increases alder growth and nitrogen fixation
Authors: Zekveld Corinthe , Markham John
Published: April 2011

Plants can respond to herbivore damage by mounting a resistance response or by compensating for lost fitness. Both plant nutrition and interactions with soil microbes can affect these responses. It has been shown that resistance responses can occur before plants have been attacked by herbivores. Here we show that a tolerance type of response can occur when plants are exposed to, but not fed on by, herbivores. Alnus viridis (Chaix) DC. spp. crispa (Ait.) Turrill were grown in sealed containers under positive air pressure with either 0.5 mmol·L–1 or 2.0 mmol·L–1 nitrate and either inoculated or not inoculated with Frankia , their nitrogen-fixing symbiont. Plants were then exposed to the genus-specific aphid Prociphilus tessallatus Fitch, which failed to establish feeding colonies. Exposure to aphids, formation of nitrogen-fixing nodules, and elevated soil nitrogen levels all significantly increased plant yield with no interaction among these factors. A combination of high soil nitrogen, nodulation, and exposure to aphids resulted in the lowest plant root:shoot ratio. Plants that were grown with low nitrogen and were exposed to aphids showed increased nitrogen-fixing activity within a day of being exposed. These results provide further evidence to support the observation that plants can respond to cues from other organisms prior to receiving herbivore damage.
STUDIES ON THE RESISTANCE OF WHEAT STARCH TO DIASTATIC ACTION
Authors: Malloch J. G.
Published: April 2011

The diastatic activity of wheat flour has been definitely resolved into two independent variable factors: (1) concentration and activity of the enzyme, (2) resistance of starch to hydrolysis. The method for the measurement of starch resistance involves the inactivation of the natural diastase with sodium tungstate, washing out the excess precipitant, and the addition of a fixed amount of taka-diastase. By the use of this method it has been found that continued grinding or extraction with ether decreases the resistance of the starch. Both diastatic activity and starch resistance are affected by the conditions under which the wheat is grown. The increase in diastatic activity when wheat is sprouted is due mainly to a change in the quantity or nature of the enzyme. Several modifications in Rumsey's method for diastatic activity are recommended.
THE HYDRATION OF THE ALUMINATES OF CALCIUM.: II. THE HYDRATION PRODUCTS OF TRICALCIUM ALUMINATE
Authors: Thorvaldson T. , Grace N. S. , Vigfusson V. A.
Published: April 2011

Further studies on the isometric form of hydrated tricalcium aluminate are reported. These include methods of preparation, crystalline forms, X-ray diffraction pattern, and determinations of solubility and density. The products formed when the hexagonal form of hydrated tricalcium aluminate is dehydrated at definite vapor pressures of Water at 21 °C., were studied. The density, refractive indices, heats of solution in HCl.200 H2O, and the X-ray diffraction patterns of several probable hydrates were determined. The experimental evidence given indicates that hydrates of 3CaO.Al2O3 having 6, 8, 91/2, 101/2, and 12 moles of water are formed, but that the water in excess of 8 moles is very loosely held and that its removal does not materially affect the crystal structure. The exact composition of some of the higher hydrates requires confirmation.
POTASSIUM NITRATE IN CANADIAN CHEESE
Authors: Harrison F. C.
Published: April 2011

The addition of saltpetre (potassium nitrate) to colored cheese is shown to produce discoloration which is unevenly distributed and which becomes very marked with age. Fresh nitrated cheese gives a positive test for nitrates; on aging, the nitrite is decomposed. Nitrate-reducing organisms have been isolated from all discolored cheese. These, when inoculated into sterilized milk with annato and potassium nitrate, produce the typical flesh-colored or vinaceous-brown discoloration. Commercial saltpetre may contain nitrate-reducing organisms, as may also the water used in diluting rennet or cheese colors. Pseudomonas fluorescens, one water organism capable of producing the discoloration, was isolated. It is recommended that the use of saltpetre in cheese be immediately discontinued.
HETEROTYPIC PROPHASES IN THE ABSENCE OF CHROMOSOME PAIRING
Authors: Melburn Myrtle Chalmers
Published: April 2011

The prophases of the heterotypic division in a wheat-rye hybrid, in which the chromosomes almost always fail to mate, are described and compared with those in the pure parents in which mating is normal. Up to the end of synizesis the events in the hybrid are in all essentials exactly the same as in the pure parents. Consequently the appearances presented in these stages can have no significance in relation to mating, because mating does not occur in the hybrid. The first striking differences in behavior occur in the stages between synizesis and second contraction when the spireme of the pure species forms loops, the sides of which approximate and twist about each other; in the hybrid spireme the loops are quite irregular. At diakinesis in the pure species three bivalents can be found connected, the mode of attachment being one which could result only from a telosynaptic arrangement of chromosomes.The entire evidence obtained in this study of the wheat-rye hybrid and its parents is in accord with the theory that the spireme is composed of univalent chromosomes "in tandem", and that mating by the formation of loops begins in the post-synizetic period when chromosomes are relatively long and thin. This affords ample opportunity for cross-over phenomena.
ON RECTIFICATION AND DETECTION RECTIFICATION AND POWER PACK DESIGN
Authors: Ruedy Richard
Published: April 2011

The theory of the mercury arc rectifier is applied to the problem of rectification and detection of alternating currents by vacuum tubes, in radio work, and the meaning of the conventional detector formula is discussed in terms of this theory. For comparison the rectifying action produced in discharge tubes by virtue of their falling characteristic is calculated. The design of filters for smoothing out the rectified current is treated by making use of the results obtained from telephonic transmission lines. By means of the formulæ given for the different cases a comparison can be made between the filters with capacitance input used since 1925, and the type of filters which should be used in order to prevent temporary overloading of the power tubes. The chief experimental methods for testing the theory, and for examining the rectified current, are indicated; the advantages of the glow discharge tube oscillograph are pointed out, and its use in testing work is proposed in place of the methods hitherto followed.
THE NEPHELINE SYENITES AND PEGMATITES OF MOUNT ROYAL, MONTREAL, QUE.
Authors: Finley F. L.
Published: April 2011

The igneous succession in Mount Royal is outlined emphasizing the fact that there were two distinct advances of a nepheline syenite magma.Those rocks which are definitely known to belong to the older nepheline syenite and those known to belong to the younger are described separately.A number of types are described which belong either to the first or to the second intrusion, but whose relations are not definitely known. These include most of the nepheline syenite pegmatites, nordmarkite pegmatites, soda-rich monzonites, syenites and an unusual porphyry intermediate between a shonkinite and an essexite.Seven chemical analyses are given.
THE PENETRATION OF WATER VAPOR INTO WOOD
Authors: Pidgeon L. M. , Maass O.
Published: April 2011

The rate of diffusion of water vapor through wood has been studied through a comparison of the time taken for samples of various thickness to become saturated. This process is, in a sense, the converse of natural drying, and for comparative purposes is more amenable to careful control of pressure and temperature. Continuous measurements of the amount of adsorption were carried out by the use of a quartz spring balance completely enclosed in the apparatus at a constant vapor pressure.Comparative numerical values have been obtained of the rate of diffusion of water vapor through spruce (Picea canadensis) and pine (Pinus banxiana) in various directions, through heartwood and sapwood, and through samples of different lengths. The results are considered as evidence that the movement of water through wood at concentrations below the saturation point, takes place as vapor diffusion through the spaces of the wood structure due to the pressure gradient consequent on the difference of moisture content.
THE MECHANISM OF THE FORMATION OF THIURAM AND XANTHOGEN MONOSULPHIDES, AND OBSERVATIONS ON THIOCARBAMYL THIOCYANATES
Authors: Cambron Adrien
Published: April 2011

The mechanism of the desulphurizing action of alkali cyanides on thiuram and xanthogen disulphides has been determined. The reaction is shown to take place in two steps, the intermediate products formed in the first step have been identified as disubstituted thiocarbamyl thiocyanates. These thiocyanates belong to a hitherto unknown series of organic sulphur compounds.Two methods for the preparation of the new thiocarbamyl thiocyanates are described.The mechanism of the formation of monoxanthogens by the action of acid chlorides on xanthates is shown to be similar to the formation of monosulphides by the action of cyanides on disulphides.The following new compounds are described: mixed thioanhydride of ethyl carbonic and isopropyl xanthic acids, C2H6OC (O)S.CS.OC3H7 liquid; methyl phenyl thiocarbamyl isopropylxanthyl sulphide, C6H5(CH3)N.CS.S.CS.OC3H7, m.p. 42 °C.; ethylphenyl thiocarbamyl isopropylxanthyl sulphide, C6H5(C2H5)N.-CS.S.CS.OC3H7, m.p.41 °C.; methylphenyl thiocarbamyl thiocyanate C6H5(CH3)-N.CS.SCN m.p. 113.5–114 °C.; ethylphenyl thiocarbamyl thiocyanate, C6H5(C2H5)N.CS.SCN, m.p. 75.5 °C.; methyl p-tolyl thiocarbamyl thiocyanate p-CH3C6H4(CH3)N.CS.SCN, m.p. 116.5 °C.: methyl p-tolyl thiocarbamyl chloride, p-CH3C6H4(CH3)N.CS.Cl, m.p. 53–54 °C.; ethyl o-tolyl thiocarbamyl chloride, o-CH3C6H4(C2H5)N.CS.Cl, m.p. 69 °C.; α1 methylphenyl α11 phenyl dithiobiuret, C6H5(CH3).N.C.S.NH.CS.NHC6H5, m.p. 123 °C.
STUDIES ON LIGNIN AND RELATED COMPOUNDS: II GLYCOL-LIGNIN AND GLYCOL-ETHER-LIGNIN
Authors: Hibbert Harold , Marion Léo
Published: April 2011

The extraction of spruce wood meal with ethylene glycol in the presence of 0.05% HCl leads to the isolation of a lignin derivative to which the name glycol-lignin is given. If the monomethyl ether of glycol be substituted for the free alcohol, a glycol-ether-lignin is obtained which has a much higher methoxyl content than glycol-lignin. The product of extraction is therefore a compound of lignin and the solvent. A comparison of the methoxyl content of the derivatives obtained from the two lignins by methylation and hydrolysis supports this conclusion. On oxidation, glycol-lignin gives rise to a product which forms a p-bromphenylhydrazone, identical with that obtained from the product of the oxidation of ethylene glycol under the same conditions. On hydrolysis with acids glycol-lignin yields, besides 0.7% formaldehyde, a substance which reduces Fehling's solution.
SINKAGE STUDIES I. THE MODE OF PENETRATION OF WATER INTO LOGS: PRELIMINARY FIELD EXPERIMENTS
Authors: Scarth George W. , Jahn Edwin C.
Published: April 2011

The distribution of water in logs, floated in a lake, was determined and found similar to that in living trees. The trees examined belonged to the following species: jack pine, spruce, poplar and balsam, in which there is a relatively dry heartwood becoming wetter in the order named, the sapwood being wet all around, and birch in which the heartwood is equally as wet as the sapwood.The rate of radial penetration of water into the logs seems to increase in the order, birch, jack pine, spruce, balsam, poplar. Penetration takes place very slowly, even into sapwood. The advantage of a large proportion of relatively dry heartwood depends more on the initial buoyancy it confers, than on the greater resistance to penetration it may possess. Narrow outer rays and density of the wood diminish the rate of penetration in the samples studied. In air-dry logs, penetration of free water is also very slow; saturation of the cell walls precedes it at a more rapid rate. The gas in floated logs is enveloped by water and can escape only in solution. There is evidence that more gas may be liberated by fermentation of storage material in the parenchyma cells. Whether escape of gas or penetration of water is the leading factor in determining rate of sinkage is undecided at present.
CYTOLOGICAL STUDIES IN MEDICAGO, MELILOTUS AND TRIGONELLA
Authors: Fryer James R.
Published: April 2011

The investigation reported herein is an effort to secure information through the use of cytological methods, which may assist in providing a better understanding of the true relationships of species and varieties within the genus Medicago, and to compare cytologically, in a general way, this genus with the related genera Melilotus and Trigonella. In order to emphasize the present unsatisfactory taxonomic situation the morphological characters of the three genera are described and the taxonomic classifications of the species for each is reproduced as presented by Taubert (49). Classifications for Medicago by Dr. Candolle (11) and by Hegi (15) are also outlined for purposes of drawing attention to certain discrepancies between the classifications of Medicago by Taubert and by Hegi. Reference is made to specific taxonomic difficulties in Medicago. The general distributions of the three genera are given.In the section of the paper on "Cyto-taxonomic relations", an attempt is made, first, to point out five cytological principles which provide the philosophical foundation for cyto-taxonomic research; second, to summarize some of the background of literature which serves for the establishment of these principles; and third, to review a few papers reporting outstanding cyto-taxonomic investigations which demonstrate the applicability of the method. Previous cytological work on Medicago and Melilotus is then outlined. Details of observations concerning somatic chromosome morphology and numbers are recorded for 23 species and five varieties of two additional species of Medicago, for four species of Melilotus and for three species of Trigonella. A summarized statement of all cytological observations is given.In the discussion the following topics are considered in the light of the cytological data secured: general morphology of the somatic chromosomes and chromosome numbers found in the species studied, chromosome numbers and the annual or perennial habit in Medicago, different races in Medicago falcata, hybrid origin of Medicago media, taxonomic relations of Medicago lupulina, Medicago carstiensis, Medicago obscura, Medicago rigidula and Medicago arabica, and varieties of Medicago hispida. A few points of purely cytological interest are also discussed, viz., tetraploid chimeral areas, nucleolar remnants, and the peculiar anaphase chromosomes in somatic divisions.In general it is concluded that these cytological studies have yielded information which can be utilized very effectively in clearing up some of the taxonomic problems, particularly, in the genus Medicago. It is predicted that the cytological information will also be useful to plant breeders who may contemplate interspecific hybridization among any of the species studied.
SOIL AS A SOURCE OF INFECTION OF HONEY BY SUGAR-TOLERANT YEASTS
Authors: Lochhead A. G. , Farrell Leone
Published: April 2011

Examination of soil from different locations, extending over a twelve-month period, for the presence of sugar-tolerant yeasts capable of fermenting honey, showed that only in the case of apiary ground was the soil regularly infected by such organisms. Ordinary field soil is not to be considered a primary source of infection of honey, sugar-tolerant yeasts not being regarded as members of the normal soil microflora. Sugar-tolerant yeasts, in apiary soils, are able to remain viable through the winter in frozen soil, but are cold-enduring rather than psychrophilic. From the soil 166 cultures of sugar-tolerant yeasts were isolated and classified. These were found to represent seven types considered as six species with one sub-species, three being types found in fermented honey. A description of the yeasts is given.
SINKAGE STUDIES IV. THE MECHANISM OF THE ABSORPTION OF WATER BY WOOD BLOCKS
Authors: Scarth Geo. W.
Published: April 2011

Uniform blocks of white pine wood were allowed to absorb water under various conditions of external and internal pressure, and in the presence and absence of air. The results shown graphically give some idea of the quantitative relation existing between penetration of water into wood and the various forces operating. It is concluded that the rate of penetration of water into an immersed block of coniferous heartwood is fixed by the rate at which the air in the block can dissolve and diffuse out.Applied to log sinkage, these findings show that under most conditions the limiting factor is the rate of escape of air from the log.
HAEMATURIA VESICALIS
Authors: Fleming R. H. , Fowler F. L. , Clark R. H.
Published: April 2011

Analysis of the blood of cattle affected with Haematuria vesicalis shows its composition, with few exceptions, to be within the normal range. Two remedies have been found to have a beneficial effect upon cattle suffering from this disease; first, a change of drinking water from surface water to Artesian well water, second, the administration of ground coral rock. The surface water, the Artesian well water and the coral rock from the affected areas have been analysed, and from these analyses certain possible causes for the improvement above noted have been drawn; further field experiments are outlined to test these suggestions.
PENETRATION STUDIES THE PATH OF LIQUID PENETRATION IN JACK PINE
Authors: Johnston H. Wyatt , Maass O.
Published: April 2011

Quantitative measurements have been made, for the first time, of the rate at which liquids penetrate into wood in terms of the velocity normal to the wood-liquid interface. The effects upon this rate, of species, previous history, structure, orientation, thickness, nature of liquid, pressure head, temperature and time have been examined and measured. It has been found that wood behaves largely in a reversible manner provided the treatment does not alter its structure. A technique has been devised for maintaining a single chip in an unvarying environment and following the progress of the cooking process by the variation of the rate of flow of the cooking liquor through the specimen. An attempt is made to examine flow m wood from the standpoint of hydraulics, and a structure is suggested which agrees well with existing anatomical information and gives values for resistance to flow which compare favorably with experiment.
THE INFLUENCE OF HYDROGEN IONS ON THE FENTON REACTION
Authors: Hatcher W. H. , Sturrock M. G.
Published: April 2011

In the preparation of dihydroxy maleic acid from tartaric acid by hydrogen peroxide in the presence of ferrous sulphate, the very small yields are the result of inactivation of the catalyst by the production of the relatively strong dihydroxy maleic acid; this reaction product undergoes such rearrangement to an isomer as prevents quantitative separation. By means of conductivity measurements of the reaction mixture, the course of the reaction is accurately followed.The existence of the tautomeric keto form of dihydroxy maleic acid, first suggested by Nef as an alternative formula, has been clearly indicated.The search for a procedure which will improve the yield of dihydroxy maleic acid is now restricted to the discovery of some compound which will at the same time reduce the hydrogen ion concentration and shift the equilibrium in favor of the enol form.
THE HEATING OF ELECTROLYTES IN HIGH FREQUENCY FIELDS
Authors: McLennan F.R.S. J. C. , Burton M.A. A. C.
Published: April 2011

In this investigation the heating of solutions of simple electrolytes of varying concentrations when irradiated by short electromagnetic waves from 10 to 200 metres in length was measured. It was found that for a given wave-length there is a maximum heating effect produced in a medium, the specific conductivity and dielectric constant of which are connected with the frequency by a simple law. This law, proved theoretically as well as shown experimentally to hold for dilute solutions is [Formula: see text] where C = specific conductivity in absolute units, K = dielectric constant and n = frequency of wave."Skin effect" was shown theoretically and experimentally to be negligible for substances having the low conductivities studied and deep-seated heating effects were shown to be attainable with the radio waves used. The possibility of directed selective heating effects is suggested and illustrated by experiments on blood. The law shown to apply in these experiments was used to evaluate the dielectric constant of water.
STUDIES ON REACTIONS RELATING TO CARBOHYDRATES AND POLYSACCHARIDES: XXXII. THE CONSTITUTION OF SEDOSAN (ANHYDRO-SEDOHEPTOSE)
Authors: Hibbert Harold , Anderson C. G.
Published: April 2011

Methylation of sedosan (anhydro-sedoheptose) gives a tetramethyl sedosan, which on oxidation by nitric acid, yields an optically inactive trimethoxy glutaric acid. By esterifying the latter, and treating the ester with anhydrous methylamine, an optically inactive methylamide, presumably trimethoxy riboglutaro-dimethylamide is obtained. No trace of the methylamide of inactive dimethoxy succinic acid could be found. It is thus concluded that sedose possesses a 2:6 oxygen ring and that sedosan is an anhydro-sedopyranose.This is confirmed by the isolation of monotrityl sedosan, which shows that sedosan has only one primary alcohol group. Sedosan is therefore 2:7-anhydro-sedopyranose.The epimerisation of trimethyl δ-arabonolactone into trimethyl δ-ribonolactone apparently takes place only with great difficulty.The structure of sedosan is found to be in harmony with its lack of tendency towards polymerization, and this is in accordance with the views of Hibbert on the relation of structure to polymerization.
THE MAINTENANCE OF A STANDARD OF ELECTROMOTIVE FORCE: NOTES ON STANDARD WESTON CELLS
Authors: Shaw A. Norman , Reilley H. E.
Published: April 2011

A detailed procedure for the maintenance of a standard of voltage to within one or two parts in a million is described.In so far as these investigations have proceeded, neutral saturated cells have been found to be superior to acid cells as independent standards for a period of many years, though the latter are preferable for purposes of ordinary precision or shorter periods. The recommended code of procedure is briefly as follows: a number of cells should be constructed according to standard specifications with the new requirements of uniformity of container and speed of preparation, and observations made upon them every few days for a period of three months. The differences in electromotive force (at constant temperature) should be determined between each cell in the group and any one of them chosen arbitrarily as reference cell, and certain new selection and rejection rules applied. In accordance with these rules a cell should be rejected: (a) if its deviation from the mean electromotive force of the group has increased or decreased by 10 microvolts or more during the preceding two weeks; or (b) if it differs in electromotive force from the mean of the group by more than 10 +d microvolts where d is the mean deviation of the cells of the group. If d exceeds 20 microvolts the entire group should be considered untrustworthy. The selected cells should be observed for three additional months, the rejection rules again applied and if a specified proportion survive elimination, the initial reference mean of the laboratory may be established.At intervals of several months additional groups of cells, neutral and acid, should be constructed and exchanges made with laboratories possessing cells of known characteristics. Analysis of the resulting observations determines: (a) the constants in the aging* equation for the reference batch, and (b) the difference between the initial reference mean of the laboratory and the estimated value of the international reference mean.Examples of the analysis of cell observations are given, illustrating the establishment of the initial reference mean, the recapture of this value when the aging coefficients are known, and the preliminary determination of the aging equation for a given group of cells. The use of the aging equation is found to be the essential feature in the attainment of increased precision.A summary of data on standard cells is included.
THE DETECTION OF ROCK SALT BY THE METHODS OF ELECTRICAL SURVEYING
Authors: Alty T. , Alty S.
Published: April 2011

Experiments on the detection of rock salt deposits by electrical methods are described. It is shown that these methods give definite indications of the depth of the deposit when the latter is as much as 600 ft. below the surface.The interpretation of results obtained by the "single electrode probe" method is discussed.
THE BOUND WATER OF WHEAT-FLOUR SUSPENSIONS
Authors: Newton R. , Cook W. H.
Published: April 2011

The bound-water method was modified for use with flour suspensions and provided a simple means for the direct measurement of the approximate hydration of the colloidal constituents in dilute lactic acid. The average hydration of the dry matter in 15% suspensions was in the region of 40 to 50%, the value being slightly higher in washed suspensions. Starch maintained a hydration close to 30%, under all conditions investigated. The prepared proteins, in dilute lactic acid, were hydrated about 85%. The calculated hydration of the proteins as they occurred in the flour was about 100% in unwashed and 200% in washed suspensions.No significant differences were found by this method in the hydration of strong and weak flours, and it is thought that such differences as may exist are too small to be of major importance as factors in baking quality. The experimental results are harmonized with the facts concerning viscosity and the behavior of bread dough by assuming micellar aggregation of the gluten.
A STUDY OF THE MALE GENITALIA OF CANADIAN SPECIES OF PENTATOMIDAE
Authors: Baker Alex. D.
Published: April 2011

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