bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting Bird Species Distributions in Reconstructed Landscapes
Authors: THOMSON JAMES R. , Mac NALLY RALPH , FLEISHMAN ERICA , HORROCKS GREG
Published: April 2007

Abstract:  Landscape optimization for biodiversity requires prediction of species distributions under alternative revegetation scenarios. We used Bayesian model averaging with logistic regression to predict probabilities of occurrence for 61 species of birds within highly fragmented box–ironbark forests of central Victoria, Australia. We used topographic, edaphic, and climatic variables as predictors so that the models could be applied to areas where vegetation has been cleared but may be replanted. Models were evaluated with newly acquired, independent data collected in large blocks of remnant native vegetation. Successful predictions were obtained for 18 of 45 woodland species (40%). Model averaging produced more accurate predictions than “single best” models. Models were most successful for smaller‐bodied species that probably depend on particular vegetation types. Predictions for larger, generalist species, and seasonal migrants were less successful, partly because of changes in species distributions between model building (1995–1997) and validation (2004–2005) surveys. We used validated models to project occurrence probabilities for individual species across a 12,000‐km2 region, assuming native vegetation was present. These predictions are intended to be used as inputs, along with landscape context and temporal dynamics, into optimization algorithms to prioritize revegetation. Longer‐term data sets to accommodate temporal dynamics are needed to improve the predictive accuracy of models.
Effects of Tourists on Behavior and Demography of Olympic Marmots
Authors: GRIFFIN SUZANNE C. , VALOIS TANGUY , TAPER MARK L. , SCOTT MILLS L.
Published: April 2007

Abstract:  If changes in animal behavior resulting from direct human disturbance negatively affect the persistence of a given species or population, then these behavioral changes must necessarily lead to reduced demographic performance. We tested for the effects of human disturbance on Olympic marmots (Marmota olympus), a large ground‐dwelling squirrel that has disappeared from several areas where recreation levels are high. We assessed the degree to which antipredator and foraging behavior and demographic rates (survival and reproduction) differed between sites with high recreation levels (high use) and those with little or no recreation (low use). Compared with the marmots at low‐use sites, marmots at high‐use sites displayed significantly reduced responses to human approach, which could be construed as successful accommodation of disturbance or as a decrease in predator awareness. The marmots at high‐use sites also looked up more often while foraging, which suggests an increased wariness. Marmots at both types of sites had comparable reproductive and survival rates and were in similar body condition. Until now, the supposition that marmots can adjust their behavior to avoid negative demographic consequences when confronted with heavy tourism has been based on potentially ambiguous behavioral data. Our results support this hypothesis in the case of Olympic marmots and demonstrate the importance of considering demographic data when evaluating the impacts of recreation on animal populations.
PHYSIOLOGICAL MODIFICATIONS RELATED TO DENSITY INCREASE IN PERIPHYTIC ASSEMBLAGES 1
Authors: Hudon Christian , Duthie Hamish C. , Paul Brian
Published: April 2007

Periphytic communities in running waters were examined as they developed on granite rocks, concrete balls and glass slides. At equivalent cell densities, no differences in pigment concentrations, species diversity or production levels were found among the different substrata examined. Development of the assemblage appeared to result from the elongation of short algal filaments which had initially settled on the surface. As these communities matured, a distinct canopy and understory developed. Cellular metabolisms were comparable among the communities. In the understory of the communities, even though the cellular content of chl a and b did not differ, chl c and carotenoid pigment concentrations were higher than those in the over‐story.

Bicarbonate assimilation of Tabellaria fenestrata (Lyng.) Külz. and Eunotia pectinalisi var. pectinalis (O. F. Müll?) Rabh. was higher than that of the more abundant Tabellaria flocculosa (Roth.)Kütz. var. flocculosa IV (sensu Koppen) at both high and low cell densities. This probably reflects a seasonal succession of colonizing species.

Glucose assimilation appeared to be mainly attributable to bacterial activity, and algal cells of the upper layer were less active than those of the bottom. The small amount of glucose that was incorporated by the algal cells was probably absorbed passively since its amount was in direct proportion to cell volumes.
CONCHOCELIS GROWTH AND PHOTOPERIODIC CONTROL OF CONCHOSPORE RELEASE IN PORPHYRA TORTA (RHODOPHYTA) 1
Authors: Waaland J. Robert , Dickson Leal G. , Carrier John E.
Published: April 2007

We have determined the conditions which give optimal growth and conchospore release in laboratory cultures of free conchocelis of the red alga Porphyra torta Krishnamurthy. With cool white fluorescent light on a 16L.8D photoregime, the fastest sustained growth (5% volume increase d−1) was observed from 10–15°C and 25–100 μE‐m −2.s−1; slightly faster growth was observed at 15°C and 300 μE.m−2.s−1, but such conditions are close to lethal. Conchoporangin will form under a wide range of conditions in conchocelis of this species. However, conchospores will mature and release only when the cultures are exposed to a short day photoperiod. The critical pholoperiod is just shorter than 12 h, The minimum number of photoinductive cycles for complete conchospore release is four for a range of conditions but can be just one depending on pretreatment.
THE ECOLOGICAL IMPLICATIONS OF GROWTH FORMS IN EPIBENTHIC DIATOMS 1
Authors: Hudon Christiane , Legendre Pierre
Published: April 2007

This paper evaluates the utilisation of space by epibenthic diatom cells, as a response to environmental variations. The aggregation pattern of five species of epibenthic diatoms was quantified and compared to provide evidence for the significance of cell motility as an adaptive mechanism for space occupation and monopoly. The epibenthic diatoms included (1) non‐mobile colonial species forming either fan‐shaped (Synedra tabulata (Ag)Kz.) or arborescent (Gomphonema kamtschaticum var. californicum Grun.) colonies; (2) slow‐moving (Cocconeis costata Greg, and Amphora pusio Cl.), and (3) fast‐moving (Navicula direct a (W. Sm.) Ra.) non‐colonial species. The aggregation pattern of S. tabulata did not vary significantly among six different light intensities manipulated in nature. The major patterns of aggregation were identified using analysis of covariance and dummy‐variable regression. Highly mobile N. directa are significantly less aggregated than the four other diatom species. Non‐mobile and slow‐moving species show a similar, highly aggregated pattern. The occurrence of two patterns of spatial dispersion indicates that growth forms bear far‐ranging ecological implications with respect to colonization strategies, immigration, and possibly impact by grazers. An integrated model of growth form characteristics, biological properties, and ecological implications is presented for epibenthic diatoms.
HETEROTROPHY AND PHOTOHETEROTROPHY BY ANTARCTIC MICROALGAE: LIGHT‐DEPENDENT INCORPORATION OF AMINO ACIDS AND GLUCOSE 1
Authors: Rivkin Richard B. , Putt Mary
Published: April 2007

Diatoms isolated from the benthic, planktonic and sea ice microbial communities in McMurdo Sound, Antarctica assimilated ambient concentrations of dissolved amino acids and glucose in both the light and dark. Uptake of amino acids but not glucose was influenced by the iucubation irradiance and amino acid uptake rates were up to 250 times greater than those of glucose. Amino acids were incorporated into proteins and other complex polymers and the rates of assimilation and patterns of polymer synthesis were similar to those of the light‐saturated photosynthetic incorporation of inorganic carbon. This suggests that these diatoms can use exogenous amino acids to synthesize the essential macromolecules for heterotrophic growth. The assimilation of dissolved organic substrates could supplement light‐limited growth during the austral spring and summer as well as potentially support the heterotrophic growth of these diatoms throughout the aphotic polar winter.
CULTURING, ULTRASTRUCTURE AND COLONY FORMATION INPECTODICTYON CUBICUM(CHLOROPHYCEAE, CHLOROCOCCALES)12
Authors: Lang Norma J. , Krupp Jonathan M. , Koller Alan L.
Published: April 2007

Pectodictyon cubicumTaft collected in California develops typical eight‐celled, cuboidal colonies only in alkaline media. Vegetative cell ultrastructure is similar to that in other genera of the Chlorococcales, except for an extensive endoplasmic reticulum system paralleling the plasmalemma (termed a paramural ER). Autosporogenesis proceeds inside the parent cell wall by three mitotic divisions producing eight nuclei in two tiers of four. Cleavage furrows following paths delineated by long ER segments and indistinct microtubules bisect and then radically separate the protoplast into eight pyramidal units. Walls comprised of a thick, presumably cellulose layer and a thinner trilaminar layer (not acetolysis resistant) form as cells become rounded, except where touching. A gelatinous matrix is produced around and between cells with concentration at the three sites of prior cell contact 90 degrees apart. Pulsed production of mucilage in three solid strands forces cells to separate, and the expanding colony becomes a hollow cube with a cell at each corner.
GROWTH OF BLADES OF NEREOCYSTIS LUETKEANA (PHAEOPHYTA) IN DARKNESS 1
Authors: Kain (Jones) Joanna M. , Norton Trevor A. , Montegut Ann E.
Published: April 2007

Short term measurements were made of the relative growth rate of the fast growing portions of blades of Ncreocystis luetkeana (Merl.) Post. et Rupr. during exposure to natural daylight and during prolonged darkness. Growth was only slightly, but significantly, faster during the 12 h of daylight than during the 12 h that included 8 h of darkness. Clearly considerable growth occurred at night. In blades amputated 1 cm beyond the zone measured, growth was slower during both night and day.

In continuous darkness growth continued for up to 12 days. It was not influenced by amputation of distal blade tissue but it was increased by severance from the bulb and stipe. A mean volume increase of 50% of the blade tissue was recorded. While the organic content decreased, the drop was half that required to support the increase in volume. There was some evidence against translocation. It is possible that cellular biochemical rearrangements allow a light‐independent increase in organic material.
MORPHOLOGY AND TAXONOMY OFMERISTIELLAGEN. NOV. (SOLIERIACEAE, RHODOPHYTA)1
Authors: Gabrielson Paul W. , Cheney Donald P.
Published: April 2007

Eucheuma acanthocladum (Harvey) J. Agardh, E. gelidium (J Agardh) J. Agardh, E. echinocarpumAreschoug andE. schrammii(P. et H. Crouan) J. Agardh from the tropical and warm temperate waters of the western Atlantic Ocean and Caribbean Sea are transferred to a new genus, Meristiella. Meristiellaexhibits the following Unique combination of characters among genera in the Solieriaceae: (1) rotated periaxial cells, (2) a loosely filamentous medulla. (3) an auxiliary cell complex, (4) Single and twin connecting filaments and (5) spinose cystocarps composed of a central, small‐celled placentum, based on its reproductive features, Meristiella.is assigned to the tribe Agardhielleae. Culture experiments and herbarium studies provide evidence thatE, gelidiumandE. acantghocladumare conspecific. Lectotypes are designated for the included species.
UDPGLUCOSE PYROPHOSPHORYLASE ACTIVITY IN THE DIATOM CYCLOTELLA CRYPTICA. PATHWAY OF CHRYSOLAMINARIN BIOSYNTHESIS 1
Authors: Roessler Paul G.
Published: April 2007

UDPglucose pyrophosphorylase activity was detected in cell‐free extracts of the diatom Cyclotella cryptica TI3L Reimann, Lewin and Guillard. When assayed in the direction of UDPglucose formation, the enzyme had maximal activity at pH 7.8 and was stimulated by Mg2+and Mn2+ions. 3‐Phosphoglycerate and inorganic phosphate had little effect on enzymatic activity, and the enzyme was relatively insensitive to feedback inhibition from UDPglucose (K, > I millimolar).

A glucan was formed from UDP‐[14C]glucose in cell‐free extracts of C. cryptica. This glucan had a median molecular weight of 4600 (as determined by gel filtration chromatograbhy) and could be hydrolyzed by laminarinase. Partial acid hydrolysis of the glucan resulted in the formation of glucose and laminaribiose. but not cellobiose. These results suggest that the synthesis of chrysolaminarin (the major storage carbohydrate of diatoms) occurs via the activity of UDPglucose pyrophosphorylase. followed by glucosyl transfer from UDPglucose to the growing β‐(1–3)‐linked glucan.
PARMALES, A NEW ORDER OF MARINE CHRYSOPHYTES, WITH DESCRIPTIONS OF THREE NEW GENERA AND SEVEN NEW SPECIES1,2
Authors: Booth Beatrice C. , Marchant Harvey J.
Published: April 2007

A new order, Parmales, in the Chrysophyceae has cells with siliceous walls made up of round, triradiate and sometimes oblong plates all fitting edge to edge. In the new family, Octolaminaceae, cell walls have eight plates. Cell walls in the new genus Tetraparma have four round plates and four triradiate plates. Cell walls in the new genus Triparma have three round plates of equal size, one larger round plate, one triradiate plate and three oblong plates. In the new family, Pentalaminaceae, cell walls have three round and two triradiate plates. A total of seven new species and four subspecies are described from subarctic Pacific and Antarctic waters.
A POLYPLOID SPECIES COMPLEX IN SPIROGYRA MAXIMA (CHLOROPHYTA, ZYGNEMATACEAE), A SPECIES WITH LARGE CHROMOSOMES1
Authors: Hoshaw Robert W. , Wells Charles V. , McCourt Richard M.
Published: April 2007

A species complex in Spirogyra consists of the series of filament morphotypes of various ploidal levels arising from an original morphotype within a clonal culture or in nature. A clonal culture of filaments identified as Spirogyra maxima (Hassall) Kützing produced several morphotypes, i.e. filament types of distinctly different widths and ploidal levels. Banding patterns and satellites were visible on chromosomes stained at mitotic prophase and metaphase. The original culture of S. maxima contained filaments averaging 127 μ wide. Vegetative cells of the original culture contained six large chromosomes (>4 μ long), identifiable as three distinct pairs based on banding patterns and presence of satellites: (1) one pair of short chromosomes (ca. 5.0 μ); (2) one pair of long chromosomes (ca. 8.0 μm); and (3) a second pair of long chromosomes (ca. 9.0 μm) including a nucleolar organizing region and satellite. A larger morphotype averaging 175 μm in width contained 12 chromosomes, with two pairs of short chromosomes and four pairs of long chromosomes (satellites were usually indistinct). Aneuploid chromosome numbers ranging from 5 to 13 were observed in a few cells. Binucleate and trinucleate cells were also observed. A twobanded chromosome fragment was observed in a few cells with 6 chromosomes and a few cells with 12 chromosomes. The variety of morphotypes derived in this study could be identified as four different species of Spirogyra by conventional taxonomic criteria. The banding patterns and satellites on chromosomes suggest that three pairs of homologous chromosomes are present in filaments of the original clonal culture and that these filaments are themselves autopolyploid (diploid) descendants of ancestral form with a base chromosome number of x = 3.
FLAGELLAR ROOTS AND THE RESERVOIR CYTOSKELETON OF COLACIUM LIBELLAE (EUGLENOPHYCEAE)1
Authors: Willey Ruth L. , Wibel Ronald G.
Published: April 2007

The three flagellar roots of Colacium Ehrenberg give rise to the three microtublar bands of the reservoir cytoskeleton. The dorsal root (DR) originates at the basal body (bb1) of the emergent flagellum. It is initiated on the left side of the cell, runs toward the right side under the posterior end of the reservoir and thence anteriorly in a spiral path over the dorsal surface of the reservoir until it terminates on the left side of the eyespot. Along its length, it appears to initiate a dorsal band (DB) which forms the major dorsal portion of the reservoir cytoskeleton—the dorsal microtubules (DMT). Two roots originate at the basal body (bb2) of the non‐emergent flagellum. The ventral root (VR) runs up the left side of the cell and initiates the band of microtubules which forms part of the presumptive vestigial cytopharynx. Therefore, it forms the reinforcing microtubules (MTR) of Colacium. The intermediate root (IR) forms the para‐reservoir microtubules (PMT). Flagellar root correlation with the reservoir cytoskeletal bands strengthens their homologies with the bodonid bands and further supports the hypothesis that the euglenoids are derived from the kinetoplastid flagellates.
THE APICAL MERISTEM OF SPLACHNIDIUM RUGOSUM (PHAEOPHYTA)1
Authors: Clayton Margaret N. , Shankly Christine M.
Published: April 2007

The meristem of Splachnidium rugosum consists of a central apical cell surrounded by a region of actively dividing cells, many of which bear hairs. Conceptacle initials are scattered throughout the surface layer of the meristematic region. Conceptacle initials and apical hairs differentiate adjacent to the apical cell. The apical cell and the conceptacle initials are distinctive, pear‐shaped cells possessing similar cytological features that are consistent with significant metabolic activity. They have a nucleus surrounded by dictyosomes, a stellate chloroplast, mitochondria, and numerous vesicles and physodes. When the apical cell is damaged as a result of experimental manipulation, growth ceases. It is inferred that the apical cell controls cell division in the meristematic region and also the differentiation of conceptacle initials and apical hairs. The apical meristems of Splachnidium and species of the Fucales have several important features in common, including the growth‐regulatory role of the apical cell and the process of conceptacle initiation. The taxa may possibly have a common evolutionary origin. The problematic and unresolved taxonomic status of Splachnidium is discussed.
SYMBIOSIS IN THE PLANKTONIC FORAMINIFER, ORBULINA UNIVERSA, AND THE ISOLATION OF ITS SYMBIOTIC DINOFLAGELLATE, GYMNODINIUM BÉII SP. NOV.1
Authors: Spero Howard J.
Published: April 2007

The symbiotic association of the spinose planktonic foraminifer, Orbulina universa, with the dinoflagellate, Gymnodinium béii sp. nov., was examined with light and electron microscopy, and the symbiont was isolated into unialgal culture. The intact association is characterized by a diurnal movement of the symbionts from the distal regions of the spines during the day, to perialgal vacuoles within the host cytoplasm at night. This diurnal migration involves a daily endo‐ exocytotic cycle.

Gymnodinium béii is non‐motile and spindle‐shaped within the host, whereas it is motile and gymnodinoid in shape when in culture. Ultrastructural examination revealed two or more stalked pyrenoids penetrated by lamellae, a typical dinokaryon nucleus and no trichocysts. A distinct ‘flange’projects over the sulcus from the hypocone. The swimming behavior of this dinoflagellate was characterized by intermittent darting events. Swimming speeds during a dart reached velocities of 770 μm. s−1 as compared to a mean, non‐darting swimming velocity of 126 μm. s−1. Gymnodinium béii is eurythermal and division rates ranged between 0.16 and 0.65 divisions day−1 for culture temperatures between 6.5 and 25° C respectively.
THALLUS MORPHOLOGY AND SPORE FORMATION IN CULTURED ERYTHROCLADIA IRREGULARIS ROSENVINGE (RHODOPHYTA, BANGIOPHYCIDAE)1
Authors: Gargiulo Gaetano M. , Masi Flora De , Tripodi Giacomo
Published: April 2007

The discoid thallus of Erythrocladia irregularis is the result of a pattern of cellular divisions expressed by mono‐and endospores; the latter are described for the first time in Erythrocladia. In nutrient enriched growth conditions the discoid thallus becomes a shapeless aggregate of unicells with a wrinkled wall surface, whose plane of division is unpredictable. The cells are able to produce monosporangia with a curved wall or they form eight‐celled endosporangia. Chloroplasts have an internal pyrenoid, as is characteristic of the Erythropeltidaceae.

The observation that E. irregularis can form either a colonial cluster of unicells or a discoid thallus would lead to the assignment of the genus to the Porphyridiales; however, since this order is reserved to organisms in which only the unicellular organization can be expressed, it is suggested to maintain Erythrocladia in the Erythropeltidales.
LIGHT AND ELECTRON MICROSCOPY OF PYRENOIDS AND SPECIES DELIMITATION INVOLVULINA(CHLOROPHYTA, VOLVOCACEAE)1
Authors: Nozaki Hisayoshi , Hara Yoshiaki , Kasaki Hideo
Published: April 2007

The appearances of pyrenoids in the vegetative cells of Volvulina steinii Playfair and V. pringsheimii Starr were observed in detail by light and electron microscopy in relation to the culture age to clarify the taxonomic relationship between the two species. In V. pringsheimii, the pyrenoids were always present in the bottom of the cupshaped chloroplasts and their gross morphology did not vary in relation to the culture age, while those of V. steinii appeared de novo and developed as the culture aged. In 24‐h cultures of V. steinii, pyrenoids were not observed in the chloroplasts. In 48‐h cultures, a pyrenoid matrix developed apparently de novo in the brim of the cupshaped chloroplast. Subsequently, starch grains appeared around the pyrenoid matrix in 72‐h cultures. The volume of the matrix and the associated starch grains increased and tubular channels entered into the pyrenoid matrix in 96‐h cultures. In addition, the pyrenoid in the parental chloroplast of V. pringsheimii divided and was distributed to each daughter cell during cell divisions in daughter colony formation, while the parental pyrenoid of V. steinii did not divide and went to one of the daughter cells. Therefore, these two species can be clearly distinguished by the differences in the position of pyrenoids in the cupshaped chloroplasts and stability of pyrenoid appearance in relation to the culture age, as well as in the fate of parental pyrenoids during daughter colony formation.
AN ULTRASTRUCTURAL SURVEY OF CRYPTOMONAD PERIPLASTS USING QUICK‐FREEZING FREEZE FRACTURE TECHNIQUES1
Authors: Kugrens Paul , Lee Robert E.
Published: April 2007

A quick‐freezing technique for freeze fracturing was used to determine periplast plate types in 20 cryptomonads. With this technique cells are frozen so rapidly that major artifacts are eliminated. We propose that periplast plates are attached to the cell membrane by intramembrane particles (IMP's), consequently plate shapes are outlined by IMP distribution in fractured membranes. Round to oval, sometimes slightly angular, plates occur in Cryptomonas ovata, Cryptomonas tetrapyrenoidosa, Cryptomonas parapyrenoidifera, Cryptomonas obovata, Cryptomonas erosa and two unidentified species of Cryptomonas; large rectangular plates occur in Chroomonas pochmannii, Chroomonas coerulea and Hemiselmis sp.; small rectangular plates were found in Cryptomonas sp. (Strain SDB); square to slightly rounded plates occur in Cryptomonas chrysoidea and a single continuous plate or sheet, perforated by ejectisome pores, was observed in Cryptomonas caudata, Cryptomonas rostratiformis, Cryptomonas marssonii, Cryptomonas platyuris, Cryptomonas curvata, Cryptomonas ozolini, Chilomonas paramecium and Rhodomonas sp. Oval and square plates are described for the first time in Cryptomonas. Plate IMP's may be morphologically modified in size and shape, depending upon their location in relation to the plate, the plate ridges, and ejectisome chambers. Conformational changes in plate shapes, to form hexagons or polygons, may be induced when cells are subjected to fixation, desiccation, cryoprotectants or centrifugation.
EVIDENCE FOR A COMMON EVOLUTIONARY ORIGIN OF LIGHT‐HARVESTING FUCOXANTHIN CHLOROPHYLL a/c‐PROTEIN COMPLEXES OF PAVLOVA GYRANS (PRYMNESIOPHYCEAE) AND PHAEODACTYLUM TRICORNUTUM (BACILLARIOPHYCEAE)1
Authors: Fawley Marvin W. , Morton Sharon J. , Stewart Kenneth D. , Mattox Karl R.
Published: April 2007

A fucoxanthin‐chlorophyll a/c‐protein complex has been isolated from the prymnesiophyte Pavlova gyrans. Thylakoid membranes were treated with the mild anionic detergent sodium taurodeoxycholate followed by sucrose density gradient centrifugation. The brown fraction produced by this procedure was treated with Triton X‐100 followed by a second sucrose density gradient centrifugation. A brown fraction isolated from this gradient was shown to be a light‐harvesting complex nearly identical to that which is present in the diatom Phaeodactylum tricornutum. The complexes from the two organisms have nearly identical absorption and flourescence spectra, both complexes contain fucoxanthin and two other carotenoids, both contain four polypeptides of similar molecular weights, and polypeptides from both complexes cross react with antibodies raised to polypeptides of the Phaeodactylum tricornutum complex. Results suggest a common evolutionary origin for these light‐harvesting complexes, in apparent contrast to the great differences in cell structure between prymnesiophytes and diatoms.
Gene profile in periodontal ligament cells and clones with enamel matrix proteins derivative
Authors: Barkana Idit , Alexopoulou Eleni , Ziv Shoshi , Jacob‐Hirsch Jasmin , Amariglio Ninette , Pitaru Sandu , Vardimon Alexander D. , Nemcovsky Carlos E.
Published: April 2007

Aim: Evaluate enamel matrix proteins derivative effect on gene expression profiles in cultured human periodontal ligament cell population and its clones.

Material and Methods: Human periodontal ligament (PDL) cells were explanted. Cell cloning was performed and clones classified into fibroblastic (FB) and mineralized tissue forming (MTF) according to their capacity to express alkaline phosphatase and form mineralized tissue. All cell cultures were grown for 7 days, with and without enamel proteins added to the medium. Following RNA extraction, expression profiling was performed by hybridization with a DNA micro‐array. Selected genes differed from the control at a significant level smaller than p<0.01.

Results: Enamel proteins induced major qualitative changes in mRNA expression in all PDL cell populations, differently affecting the entire PDL cell population and its clones. In the entire PDL cell population, enamel proteins significantly enhanced PDL cell function, with a general effect on enhanced cell functional metabolism.

Conclusions: Enamel proteins enhanced gene expression responsible for protein and mineralized tissue synthesis in the entire PDL population. In the MTF clones, nucleic acid metabolism, protein metabolism and signal transduction related genes were up‐regulated, while in the FB clones, up‐regulated genes were related to cell adhesion, nucleic acid metabolism and signal transduction.
Osmotic adjustment of chickpea (Cicer arietinum) is not associated with changes in carbohydrate composition or leaf gas exchange under drought
Authors: Basu P.S. , Berger J.D. , Turner N.C. , Chaturvedi S.K. , Ali M. , Siddique K.H.M.
Published: April 2007

Genetic differences in osmotic adjustment (OA) have been reported among chickpea (Cicer arietinum) cultivars. In this study eight advanced breeding lines (ABLs) derived from a cross between CTS 60543 (high OA) and Kaniva (low OA) and Tyson (medium OA) and Kaniva, along with the parents, were evaluated for OA, leaf carbohydrate composition and leaf gas exchange under dryland field conditions in India. The water potential (WP) decreased to lower values (less than −2.5 MPa) in Tyson, M 110 and M 86 than in the other genotypes. With decrease in WP, OA increased by 0.5 MPa in Kaniva and CTS 60543 to 1.3 MPa in M 55. As the decrease in WP varied with genotype, when OA was regressed against WP M 39 and M 55 had greater increases in OA with decrease in WP than the remaining nine genotypes, including the parents. As WP decreased, leaf starch content decreased while total soluble sugars, hexoses and sucrose increased: the decrease in starch was much smaller in M 93 and M 129 than in Tyson and M 51, but genotypic differences could not be detected in the increase in total sugars, hexoses or sucrose. The rates of photosynthesis and transpiration decreased as the WP became more negative, but M 129 reached low rates of photosynthesis (2 μmol m−2 s−1) and transpiration at a WP of −1.7 MPa, whereas Tyson reached the same low rate at −2.4 MPa. While OA varied among the chickpea genotypes, the differences were not associated with the changes in carbohydrate composition or the rates of gas exchange at low values of WP. Further, the degree of OA of the 11 genotypes was not the same as when they were selected for differences in OA under rainout shelter conditions in the field in Australia, suggesting that OA may show poor stability depending upon the stress level, location or physiological stage of the plant. This suggests that OA is not a valuable drought‐resistance trait to select for in chickpea breeding programmes.
Photosynthesis and transpiration of tomato and CO2 fluxes in a greenhouse under changing environmental conditions in winter
Authors: Tartachnyk I. I. , Blanke M. M.
Published: April 2007

Responses of tomato leaves in a greenhouse to light and CO2 were examined at the transient stage at the end of winter, when both photoperiod and irradiance gradually increase. Additionally, CO2 fluxes were calculated for a greenhouse without supplementary lighting and without CO2 enrichment based on CO2 sinks (plant photosynthesis) and CO2 sources (plant and substrate respiration). In January, tomato leaves in the greenhouse showed low photosynthesis with a maximum assimilation of 6–8 μmol CO2 m−2 s−1, a quantum yield of 0.06 μmol CO2 μmol−1 photosynthetic active radiation (PAR) and a low light compensation point of 26 μmol PAR m−2 s−1, a combination which classifies them as shade leaves. In February, tomato leaves increased their light compensation point to 39 μmol PAR m−2 s−1 and quantum yield to 0.08, the former indicating the adaptation to increased irradiance and photoperiod. These tomato leaves increased their transpiration from 0.4 to 0.9 in January to ∼2 mmol H2O m−2 s−1 in February. Both photosynthesis and transpiration were primarily limited by light but neither by stomatal conductivity nor by CO2. In January, light response of photosynthesis, dark respiration and transpiration were negligibly affected by increasing CO2 concentrations from 600 to 900 ppm CO2 under low light conditions, indicating no benefit of CO2 enrichment unless light intensity increased. In February, tomato leaves were photoinhibited at inherent greenhouse CO2 concentrations on the first sunny day; this photoinhibition was further enhanced by an increased CO2 concentration of 1000 ppm. CO2 fluxes in the greenhouse appeared strongly dependent on solar radiation. After exceeding the light compensation point in the morning, greenhouse CO2 concentrations decreased by 58 or by 110 ppm CO2 h−1 on a sunny day in January or February and by 23 ppm on overcast days in both months. Calculated per overall tomato canopy, plant photosynthesis contributed 42–50% to the morning CO2 depletion in the greenhouse. Dark respiration of tomato leaves was ∼2 μmol CO2 m−2 s−1 in January and ∼3 μmol CO2 m−2 s−1 in February. This dark respiration resulted in rises of 15 and 17 ppm CO2 h−1 at night in the greenhouse compartment and was identified as primary source of CO2. Respiration of the substrate used to grow the plants, which produced 7.3 ppm CO2 h−1, was identified as secondary source of CO2. The combined plant and substrate respiration resulted in peaks of up to 900 ppm CO2 in the greenhouse before dawn.
Proliferation and apoptosis in mammary epithelium during the rat oestrous cycle
Authors: Strange R. , Westerlind K. C. , Ziemiecki A. , Andres A.‐C.
Published: April 2007

Aim:  During each oestrous cycle, the mammary gland is subject to changes in ovarian hormone levels. It responds with limited proliferation, differentiation and regression. To understand the processes resulting in these changes, particularly the regulation of cell death, we examined protein levels in mammary epithelium during the oestrous cycle of the Sprague‐Dawley rat.

Methods:  Studies of serum hormone levels, vaginal smears, uterine weight and morphology, mammary gland morphology, proliferation and apoptotic indices, and protein levels during the stages of the Sprague‐Dawley rat oestrous cycle were used to examine the response of mammary epithelium to the oestrous cycle.

Results:  Proliferation of mammary epithelium was greater in diestrus and proestrus, while apoptosis was increased in metestrus and diestrus. Growth factor‐, hormone‐ and anchorage‐mediated cell survival signalling, indicated by activation of Stat5A, FAK and Akt 1 and expression of anti‐apoptotic Bcl‐2 family members, was greater in proestrus and reduced in metestrus. In contrast, the levels of pro‐apoptotic Bcl‐2 family members and proteins associated with apoptosis in mammary epithelium (TGFβ3, pStat3) were increased during metestrus and diestrus.

Conclusion:  Decreases in growth factor, hormone and cell attachment survival signals corresponded with increased apoptosis during the second half of the oestrous cycle. The protein levels detected during oestrus suggest parallels to apoptosis in mammary involution.
An overview of methods for detection of factor V Leiden and the prothrombin G20210A mutations
Authors: COOPER P. C. , REZENDE S. M.
Published: April 2007

Venous thromboembolism, represented by deep venous thrombosis and pulmonary embolism, is a common disease with high mortality and morbidity. Within the last 25 years, risk factors for venous thromboembolism have been linked to mutations in the genes of the coagulation/anticoagulation system. Factor V Leiden and the prothrombin G20210A mutations are the most prevalent inherited risk factors predisposing to venous thromboembolism in the Western world. Tests to detect these mutations are carried out when investigating a personal or family history of venous thromboembolism. At the present, there are several different methods available for the detection of these mutations in the laboratory. The choice of the method will depend on many variables. This article is aimed at reviewing the available methods for the detection of factor V Leiden and prothrombin G20210A mutations, their principle, applicability, advantages and disadvantages of use.
THE HLD INDEX BY RACE AND INGESTION OF FLUORIDATED WATER
Authors: Szwejda Louis F.
Published: April 2007

What does the ingestion of fluoride do for occlusion in North Carolina?
POLICIES OF STATE DIVISIONS OF DENTAL PUBLIC HEALTH AND STATE DENTAL SOCIETIES REGARDING PUBLIC HEALTH ACTIVITIES OF COMMERCIAL COMPANIES*
Authors: Arra Michael C.
Published: April 2007

From Wisconsin comes an opinion that it is time to review the activities of commercial companies engaging in dental‐health education.
DENTAL PREPAYMENT FOR UNIVERSITY STUDENTS
Authors: Pelton Walter J.
Published: April 2007

The writer points out unhesitantly that dental deans have failed miserably in providing dental services for their own students.
THE LOSS OF FIRST PERMANENT MOLARS IN A FLUORIDATED AND A FLUORIDE‐DEFICIENT COMMUNITY
Authors: Douglas Bruce L. , Lerner Monroe , Wallace Donald A.
Published: April 2007

This paper is presented as a “spring‐board” to introduce a series of reports about the impact of fluoridation of drinking water on the practice of dentistry—an investigation begun at the University of Illinois.
EVALUATION OF DENTAL HEALTH EDUCATION IN THE GREATER LEECH LAKE DENTAL PROJECT OF CASS COUNTY, MINNESOTA
Authors: Jordan William A. , Pugnier Vincent A.
Published: April 2007

How effective is education for dental health by schools? Here is another effort to find out.
EXPANDING THE FUNCTIONS OF DENTAL ASSISTANTS; AN EVALUATION OF SUGGESTIONS*
Authors: Lathrop Robert L.
Published: April 2007

The Lathrop has presented a tremendous review and appraisal of the information available on expanded services for dental assistants.
Approaches to the Design and Evaluation of Pilot Programs of Dental Care*
Authors: Donnelly Charles J.
Published: April 2007

The Chief of the Research Grants Unit of the Division of Dental Health has worked out an approach for the design and evaluation of pilot‐programs designed to learn more about the administration of dental programs for children.
DENTAL MANPOWER; It's Development and Use in a National Program of Care for Children*
Authors: Trithart Albert H.
Published: April 2007

Here is a point of view, carefully expressed, on two phases of the problem in supplying additional dental personnel. A Committee of the Association worked out this report.
An Assessment of the Knowledge and the Practice of Oral Health by Selected School Children in Kalamazoo, Michigan*
Authors: Love William C.
Published: April 2007

Dr. Love reports in some detail, another attempt to obtain the essential information for evaluating the effectiveness of the teaching‐practices to gain oral health.
Dental Health Education for All West Virginians I. Its Organization
Authors: Salerno Fred R. , Bennett Carroll G.
Published: April 2007

The writers present the program of dental health education now instituted in West Virginia.
OPERATION AND COSTS IN ALABAMA'S PUBLIC DENTAL CLINICS 1965
Authors: Shory Naseeb L.
Published: April 2007

While a number of people have theorized about a system of relative values, Alabama designed a system and used it as an evaluatory instrument.
GAINING EXPERIENCE IN TEACHING COMMUNITY DENTISTRY*
Authors: Douglass Chester W. , Petterson Elof O.
Published: April 2007

From their personal participation, these two dentists recommend development of sites in which students of dental public health can gain practical experience for teaching community dentistry in a university.
A DEFINITION OF PREVENTIVE DENTISTRY
Authors: Gerrie Norman F.
Published: April 2007

Dr. Gerrie, having found no satisfactory definition of Preventive Dentstry invites criticism of his definition from everyone who reads it.
IDENTIFYING SOCIALLY SENSITIVE APPLICANTS FOR DENTAL SCHOOLS*
Authors: Lucas Robert J. , Shrock John G.
Published: April 2007

These two investigators have provided an interesting beginning for the selection of dental students in the future.
THE VANISHING NEGRO DENTIST
Authors: Applewhite Harold L.
Published: April 2007

Dr. Applewhite writes with considerable convictioii about the void in Negro dentists, and presents some practical recommendations for a solution.
THE CARIOSTATIC EFFECTIVENESS OF A PHOSPHATE‐FLUORIDE GEL ADMINISTERED ANNUALLY TO SCHOOL CHILDREN; FINAL RESULTS
Authors: Bryan Eugene T. , Williams J. Earl
Published: April 2007

Drs. Bryan and Williams have submitted the follow‐up study of their experience, after two years, with phosphate‐fluoride gel.
PUBLIC HEALTH DENTISTS AND DENTAL HYGIENISTS EXPRESS AN INTEREST IN CONTINUING EDUCATION
Authors: Keevil Joan M.
Published: April 2007

The writer of this report has gathered information that should be useful to those engaged in planning continuing education for personnel practicing dental public health.
BECOMING A SOCIALLY SENSITIVE DENTIST; A REVIEW OF SOME TRENDS*
Authors: Waldman H. Barry
Published: April 2007

This paper has been prepared as a portion of a study to investigate the status of students' sensitivity towards community life and to make recommendations for improving their sensitivity.
REVENTIVE DENTAL SERVICES IN THE VETERANS' ADMINISTRATION HOSPITAL
Authors: Shannon Ira L.
Published: April 2007

Dr. Shannon reports his long period of experience with the use of stannous fluoride in a solution free of water.
A QUANTITATIVE ASSESSMENT OF THE ORAL HYGIENE OF MENTALLY RETARDED RESIDENTS IN A STATE INSTITUTION*
Authors: Powell Elbert A.
Published: April 2007

Dr. Powell reports a survey and statistical examination of data on institutionalized, retarded residents in New Jersey, which determines that oral hygiene may be expected to vary with the degree of retardation, not with the age of individuals.
EVALUATING THE EFFECTIVENESS OF INSTRUCTION IN ORAL HYGIENE FOR MENTALLY RETARDED BOYS
Authors: Reynolds William E. , Block Robert M.
Published: April 2007

Dr. Reynolds and his group demonstrate that effective toothbrushing can be taught to a group of retarded boys.
INSTRUCTION IN ORAL HYGIENE FOR A GROUP OF DENTAL STUDENTS; ITS EFFECT ON THEIR PEERS
Authors: Newcomb Guy M.
Published: April 2007

From South Australia comes an interesting investigation of the use of modeling and its reinforcement to teach habits of oral hygiene effectively. Indentification with one's peers also served as a part of this experiment.
Dental Health of Male Inmates in a State Prison System
Authors: Salive Marcel E. , Carolla Jeffrey M. , Brewer T. Fordham
Published: April 2007

This study investigated the prevalence of decayed, missing, and filled teeth (DMFT) in a state prison system, using the opening of a new institution as an opportunity to examine a cross‐section of the state male inmate population routinely. A representative sample of 178 male inmates was examined by a single dentist, and the results were linked to demographic information.

This study found a mean DMFT of 10.5 for inmates aged 18‐29, 17.1 for inmates aged 30‐44, and 22.4 for inmates over age 44. In the 18–29 age group, white inmates had more filled teeth than blacks (P < .005) and more missing teeth (P = .06). Missing teeth increased by 0.54 teeth/year of age (P < .001) and DMFT increased by 0.66 teeth/year of age (P < .001). The number of decayed teeth was explained using negative reciprocal time incarcerated (−1/T), and declined by 1.30 teeth between the sixth and 12th month of incarceration (P < .01). This may have been due to a treatment effect, or by selective loss of the population with poorer teeth. Comparison with US employed adults standardized to the study population showed that inmates had more missing teeth at every age, and a greater percent of unmet dental needs.
Book Review
Authors: Walsh Margaret M.
Published: April 2007

Book reviewed in this article:

Allen DL, McFall WT, Jenzano JW. PERIODONTICS FOR THE DENTAL HYGIENIST.
Effect of Residence in a Fluoridated Community on the Incidence of Coronal and Root Caries in an Older Adult Population
Authors: Hunt Ronald J. , Eldredge Janis B. , Beck James D.
Published: April 2007

Eighteen‐month caries incidence among older adult residents of fluoridated and nonfluoridated communities was compared. Rates for both coronal and root caries were consistently lower among long‐term residents of the fluoridated communities than among lifelong residents of nonfluoridated communities. Coronal caries incidence was significantly lower for people who had resided in fluoridated communities for more than 30 years (1.95 vs 1.33 surfaces). Root caries incidence was significantly less among residents for more than 40 years (0.56 vs1.11 surfaces). Fluoridation appeared to be beneficial for the older adults examined, even though the exposure to fluoridated water began in adulthood.
AIDS and Infection Control: Amsterdam Dentists Surveyed
Authors: ter Horst Guusje , Hammann‐Konings Gabrlelle M. J. , van Hegten Mlrjam J. , Maritz Bertie M. , Meijer Karin L. , Meyland Yolanda M. , van der Waag Chris
Published: April 2007

In March 1988 all Amsterdam dentists (N=470) were sent a questionnaire to assess the extent of compliance with guidelines from the Health Council to prevent HIV transmission in dental practice. Response rate was 62 percent. Gloves, masks, and other protective garments were widely used. Other infection control procedures, like sterilizing instruments, were often not followed in ways recommended by the Health Council. To date, 60 percent of the respondents did not spend more than US$2,500 for protective garments or special equipment. Planned expenditure is substantially higher. One‐quarter of the respondents were certain to have one or more HIV‐seropositive patients, and 35 percent believed they did. When taking the medical history, almost one‐third of the dentists ask questions to assess whether a patient is possibly HIV seropositive. Forty percent of the dentists hold the opinion that it is necessary for a dentist to know whether a patient is HIV seropositive. This is against Health Council views. Thirty percent of the respondents are definitely fearful of AIDS infection and want additional information or training on this topic.
Issues in Cost Effectiveness in Health Care
Authors: Warner Kenneth E.
Published: April 2007

Cost‐effectiveness analysis (CEA) is becoming increasingly popular as society moves toward rationalizing health costs. This review describes the applications and limitations of the technique. Conceptually simple though frequently complicated in application, CEA compares the cost of a procedure with its effectiveness, thus helping an administrator to judge whether the procedure is worth its cost. CEA also permits comparison of various interventions that result in a similar health outcome. A major benefit of CEA is that it forces decision makers to confront the tradeoffs implicit in all decisions regarding alternative approaches. Limitations of the CEA philosophy and technique also have to be understood if it is to be employed effectively; it is not an assessment of cost savings, nor is it a decision‐making technique because it does not incorporate value judgments. A number of potential applications to dentistry are described.
Effectiveness of Mouthrinsing with Fluoride Solutions in Preventing Coronal and Root Caries
Authors: Leverett Dennis H.
Published: April 2007

Fluoride mouthrinses have been used extensively for the past 15 years to prevent dental caries in children. Their use has been especially widespread in organized school‐based programs in the US. Nearly three dozen clinical studies of fluoride mouthrinses, both with and without placebo controls, have been reported in the literature since the early 1960s. The overwhelming majority of those studies report statistically significant caries inhibition from the use of the products. Most of the studies were published prior to the knowledge of a decline in caries prevalence during the past 30 years. Consequently, the results of those studies lacking a placebo control group have been challenged. Even randomized clinical trials with appropriate control groups appear to be reporting declining differences between test and control groups. Using a model based on annual caries increments from published studies, the conclusion is reached that future use of fluoride mouthrinses is unlikely to result in annual savings in DMF increment greater than 0.4 surfaces, regardless of age of rinsers.