bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biogeochemistry of microbial mats under Precambrian environmental conditions: a modelling study
Authors: HERMAN E. K. , KUMP L. R. 
Published: November 2005

ABSTRACTMicrobial mats have arguably been the most important ecosystem on Earth over its 3.5 Gyr inhabitation. Mats have persisted as consortia for billions of years and occupy some of Earth's most hostile environments. With rare exceptions (e.g. microbial mats developed on geothermal springs at Yellowstone National Park, USA), today's mats do not exist under conditions analogous to Precambrian habitats with substantially lower oxygen and sulphate concentrations. This study uses a numerical model of a microbial mat to investigate how mat composition in the past might have differed from modern mats.We present a numerical model of mat biogeochemistry that simulates the growth of cyanobacteria (CYA), colourless sulphur bacteria (CSB), and purple sulphur bacteria (PSB), with sulphate‐reducing bacteria (SRB) and heterotrophic bacteria represented by parameterized sulphate reduction rates and heterotrophic consumption rates, respectively. Variations in the availability of light, oxygen, sulphide, and sulphate at the upper boundary of the mat are the driving forces in the model. Mats with remarkably similar biomass and chemical profiles develop in models under oxygen boundary conditions ranging from 2.5 × 10−13 to 0.25 mm and sulphate boundary concentrations ranging from 0.29 to 29 mm, designed to simulate various environments from Archean to modern. The modelled mats show little sensitivity to oxygen boundary conditions because, independent of the overlying oxygen concentrations, cyanobacterial photosynthesis creates similar O2 concentrations of 0.45–0.65 mm in the upper reaches of the mat during the photoperiod. Varying sulphate boundary conditions have more effect on the biological composition of the mat. Sulphide generated from sulphate reduction controls the magnitude and distribution of the PSB population, and plays a part in the distribution of CSB. CSB are the most sensitive species to environmental change, varying with oxygen and sulphide.
Fan‐shaped staurolite in the Bolton syncline, eastern Connecticut: evidence for porphyroblast rotation during growth
Authors: BUSA M. D. , GRAY N. H. 
Published: November 2005

AbstractFan‐shaped polycrystalline staurolite porphyroblasts, 3–4 cm in length and 0.5 cm in width, occur together with centimetre‐sized euhedral prismatic staurolite porphyroblasts in pelitic schists of the Littleton Formation on the western overturned limb of the Bolton syncline in eastern Connecticut. The fans consist of intergrown planar splays of [001] elongated prisms, which are crudely radial from a single apex. The apical angles of the radial groupings range up to 70°. The orientations of the individual staurolite prisms are related by a rigid rotation about an axis perpendicular to the fan plane. The zone axes [001] always lie in the plane of the fan. Although the angle between the [100] zone axes of the individual prisms is uniform in each fan, it ranges from +30° to −30° in different fans. Internally, the fans display: (i) remnants of a passively captured Si foliation defined by disc‐shaped quartz blebs (type 1 inclusions) and layers of very fine carbonaceous material and tabular ilmenite platelets; (ii) bent staurolite blades and undulose extinction along low‐angle (010) subgrain boundaries near the apex of the fans; (iii) wedge‐shaped dilatational zones containing equigranular inclusion‐free quartz, mica and staurolite, and (iv) growth‐related quartz inclusion trails roughly perpendicular to a crystal face (type 2 inclusions). The Si inclusion trails are typically perpendicular to the fan surface, radiate parallel to the blades, and show little to no curvature except at the very edge of the fans where they abruptly curve through nearly 90° into parallelism with an external Se foliation. Careful examination of the three‐dimensional geometry of fans based on U‐stage measurements, serial sections and two‐circle optical goniometric measurements permits a detailed reconstruction of their sequential development. The origin of a fan involves limited intracrystalline deformation and brittle crack dilation, spalling, rotation, and growth of small marginal fragments and of new staurolite along wedge‐shaped zones along the Si inclusion surfaces. Fans preferentially develop in porphyroblasts in which Si is subparallel to the 010 cleavage. These internal features reflect the rotation and deformation of a brittle porphyroblast relative to syn‐growth shear stresses.
Hippocampal Formation Involvement in a Language‐activation Task in Patients with Mesial Temporal Lobe Epilepsy
Authors: Bartha Lisa , Mariën Peter , Brenneis Christian , Trieb Thomas , Kremser Christian , Ortler Martin , Walser Gerald , Dobesberger Judith , Embacher Norbert , Gotwald Thaddäus , Karner Elfriede , Köylü Buelent , Bauer Gerhard , Trinka Eugen , Benke Thomas 
Published: November 2005

Summary:  Purpose: The study aims to explore the contribution of the hippocampal formation to the retained language‐comprehension network in patients with unilateral mesial temporal lobe epilepsy (TLE). Methods: We performed a functional magnetic resonance (MRI) study based on a language comprehension paradigm in 45 right‐handed patients with unilateral mesial TLE and 35 healthy control subjects. Activations in the hippocampal formations in both hemispheres were analyzed for each subject as well as for groups of left TLE, right TLE, and controls. Results: In sum, 82% of TLE patients displayed hippocampal activations. A significant difference in hippocampal activation between left and right TLE was found: Right TLE patients showed increased activity in the left hippocampal formation compared with left TLE patients. In contrast, patients with left TLE did not show increased activity in the right hippocampal formation compared with right TLE patients. In comparison with a healthy control group, right TLE patients activated the left hippocampal formation to a greater extent, whereas patients with left TLE did not activate the right hippocampal formation to a greater degree. These findings point to an increased involvement of the left hippocampal formation during a language‐comprehension task in right TLE patients. In contrast, left TLE in right‐handed patients seems not associated with an enhanced involvement of the right hippocampal formation in retained language comprehension. Conclusions: These findings suggest that effective language comprehension in right‐handed subjects with TLE depends on the involvement of the left hippocampal formation and underline the risks of postoperative language decline in patients with left TLE.
Utility of the Boston Naming Test in Predicting Ultimate Side of Surgery in Patients with Medically Intractable Temporal Lobe Epilepsy
Authors: Busch Robyn M. , Frazier Thomas W. , Haggerty Kathryn A. , Kubu Cynthia S. 
Published: November 2005

Summary:  Purpose: Confrontation naming tasks have long been presumed to be sensitive to left temporal dysfunction and, consequently, are frequently used in the evaluation of surgical epilepsy patients. Despite wide and frequent use, few studies have examined the utility of confrontation naming tasks in individuals with temporal lobe epilepsy (TLE). Methods: The current study examined the presurgical Boston Naming Test (BNT) performance of 217 right‐handed adult patients with intractable TLE (left, 108; right, 109) to determine the utility of this measure in predicting ultimate side of surgery. Results: The results support the clinical utility of the BNT in determining ultimate side of surgery and suggest that the BNT has incremental validity over and above presurgical delayed memory and intelligence scores. This relation was found to be moderated by Full Scale IQ (FSIQ), age at seizure onset, and duration of epilepsy. The use of a logistic regression equation to predict side of surgery revealed that prediction of left temporal surgery was best among patients with low BNT scores, high FSIQs, and late age at seizure onset. In contrast, right temporal surgery was best predicted among patients with high BNT scores, low FSIQs, and short duration of epilepsy. Conclusions: This study supports the clinical utility of the BNT in the preoperative evaluation of candidates for TLE surgery and highlights the importance of examining potential moderating variables when making predictions about side of surgery. This study further provides clinicians with a regression equation that can be used to predict side of surgery in patients with temporal lobe epilepsy.
Clinical and microbiological characterization of periodontal abscesses
Authors: Jaramillo Adriana , Arce Roger Mauricio , Herrera David , Betancourth Marisol , Botero Javier Enrique , Contreras Adolfo 
Published: November 2005

AbstractBackground/Aim: The knowledge of clinical features, microbial composition and susceptibility to antimicrobials of periodontal abscesses has recently improved. This descriptive clinical and microbiological study provides more information on the characteristics of periodontal abscesses.Materials and Methods: Clinical parameters and subgingival samples were examined from 54 subjects presenting 60 periodontal abscesses. Samples were cultured for anaerobic and facultative bacteria, and data were expressed as frequency detection and mean proportion of isolation for microorganisms. Selected isolates of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia/nigrescens were used to test susceptibility to amoxicillin, azithromycin, tetracycline and metronidazole. Statistical descriptive analysis was conducted.Results: Most periodontal abscesses were present in patients with ongoing Chronic Periodontitis. Bleeding on probing, tumefaction and suppuration were present in almost all abscesses. Affected teeth were lower anterior teeth, upper anterior teeth and lower molars. The subgingival microbiota was composed of periodontal pathogens such as Fusobacterium spp. (75%), P. intermedia/nigrescens (60%), P. gingivalis (51%) and A. actinomycetemcomitans (30%). Some periodontopathogens showed antimicrobial resistance to tetracycline, metronidazole and amoxicillin, but not to azithromycin.Conclusions: Periodontal abscesses showed typical clinical features associated with untreated periodontitis, and the organisms identified were important periodontopathic bacteria. Rationale use of antibiotic adjunctive therapy in abscess treatment should be taken into account.
Controlled clinical and psychometric studies on the relation between periodontitis and depressive mood
Authors: Saletu Alexander , Pirker‐Frühauf Helene , Saletu Franziska , Linzmayer Leopold , Anderer Peter , Matejka Michael 
Published: November 2005

AbstractBackground: Depressive mood is considered a risk factor for the development of periodontitis.Objectives: Investigation of the relationship between periodontitis and psychopathology utilizing psychometry (both observer‐ and self‐rating scales).Methods: Forty periodontitis patients were compared with 41 age‐ and sex‐matched controls. The percentage of smokers was similar in both groups (30%versus 24.4%). Dental variables included probing depth, clinical attachment loss (CAL), radiographic loss of attachment, papillary bleeding index (PBI) and approximal plaque index (API). Psychometry comprised the Hamilton Depression Scale, the Zung Self‐Rating Depression and Anxiety Scales, the von Zerssen Well‐being and Complaint Scales, the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the Quality‐of‐Life Index, crystallized intelligence and the Freiburg Personality Inventory (FPI).Results: Multifactorial analysis of variance demonstrated increased depression and anxiety scores, reduced well‐being, increased somatic complaints, deteriorated quality of life and introversion in periodontitis. Partial correlation analyses between psychometric measures and dental variables revealed positive correlations of periodontal disease severity/CAL with the depression/anxiety, subjective well‐being and complaints scores, and a negative correlation with quality of life. The API was negatively correlated with social orientation, and the CAL was positively correlated with somatic complaints and introversion in the FPI.Conclusion: Our clinical‐psychometric studies confirm depressive mood as a relevant pathogenetic factor for periodontitis.
Surface Microflora of Four Smear-Ripened Cheeses
Authors: Mounier Jérôme , Gelsomino Roberto , Goerges Stefanie , Vancanneyt Marc , Vandemeulebroecke Katrien , Hoste Bart , Scherer Siegfried , Swings Jean , Fitzgerald Gerald F. , Cogan Timothy M. 
Published: November 2005

ABSTRACT

The microbial composition of smear-ripened cheeses is not very clear. A total of 194 bacterial isolates and 187 yeast isolates from the surfaces of four Irish farmhouse smear-ripened cheeses were identified at the midpoint of ripening using pulsed-field gel electrophoresis (PFGE), repetitive sequence-based PCR, and 16S rRNA gene sequencing for identifying and typing the bacteria and Fourier transform infrared spectroscopy and mitochondrial DNA restriction fragment length polymorphism (mtDNA RFLP) analysis for identifying and typing the yeast. The yeast microflora was very uniform, and
Debaryomyces hansenii
was the dominant species in the four cheeses.
Yarrowia lipolytica
was also isolated in low numbers from one cheese. The bacteria were highly diverse, and 14 different species,
Corynebacterium casei
,
Corynebacterium variabile
,
Arthrobacter arilaitensis
,
Arthrobacter
sp.,
Microbacterium gubbeenense
,
Agrococcus
sp. nov.,
Brevibacterium linens
,
Staphylococcus epidermidis
,
Staphylococcus equorum
,
Staphylococcus saprophyticus
,
Micrococcus luteus
,
Halomonas venusta
,
Vibrio
sp., and
Bacillus
sp., were identified on the four cheeses. Each cheese had a more or less unique microflora with four to nine species on its surface. However, two bacteria,
C. casei
and
A. arilaitensis
, were found on each cheese. Diversity at the strain level was also observed, based on the different PFGE patterns and mtDNA RFLP profiles of the dominant bacterial and yeast species. None of the ripening cultures deliberately inoculated onto the surface were reisolated from the cheeses. This study confirms the importance of the adventitious, resident microflora in the ripening of smear cheeses.
Characterization of Enzymatic Antioxidants in the Lichen
Ramalina lacera
and Their Response to Rehydration
Authors: Weissman Lior , Garty Jacob , Hochman Ayala 
Published: November 2005

ABSTRACT

Lichens are slow-growing associations of fungi and green algae or cyanobacteria. This symbiotic association forms a common thallus that does not possess roots or a waxy cuticle and depends mainly on atmospheric input of mineral nutrients. The lifestyle of most lichens is composed of alternating periods of desiccation with low metabolic activity and hydration that induces increase in their metabolism. We have previously shown that rehydration of the naturally desiccated lichen
Ramalina lacera
resulted in a rapid increase in photosynthesis and was accompanied by a burst of intracellular production of reactive oxygen species and nitric oxide, as well as a transient decrease in water-soluble antioxidant capacity. We report here on enzymatic antioxidants of
R. lacera
and their response to rehydration. Native gel electrophoresis of crude extracts of
R. lacera
stained for superoxide dismutase (SOD) activity revealed four Fe-SOD and four Mn-SOD electromorphs that are synthesized by the alga, a Cu/Zn-SOD and a Mn-SOD that are the product of the fungus, and two catalases synthesized one by the fungus and the other by the algae. In addition, we detected glutathione reductase and glucose-6-phosphate dehydrogenase activities in crude extracts of
R. lacera
. Rehydration of the thalli resulted in a decrease in SOD activity of all forms, and a transient decrease in total catalase activity, as well as a decrease in the antioxidant auxiliary enzymes glutathione reductase and glucose-6-phosphate dehydrogenase.
Differentiation of Spores of
Bacillus subtilis
Grown in Different Media by Elemental Characterization Using Time-of-Flight Secondary Ion Mass Spectrometry
Authors: Cliff John B. , Jarman Kristin H. , Valentine Nancy B. , Golledge Steven L. , Gaspar Daniel J. , Wunschel David S. , Wahl Karen L. 
Published: November 2005

ABSTRACT

We demonstrate the use of time-of-flight secondary ion mass spectrometry (TOF-SIMS) in a forensics application to distinguish
Bacillus subtilis
spores grown in various media based on the elemental signatures of the spores. Triplicate cultures grown in each of four different media were analyzed to obtain TOF-SIMS signatures comprised of 16 elemental intensities. Analysis of variance was unable to distinguish growth medium types based on
40
Ca-normalized signatures of any single normalized element. Principal component analysis proved successful in separating the spores into groups consistent with the media in which they were prepared. Confusion matrices constructed using nearest-neighbor classification of the PCA scores confirmed the predictive utility of TOF-SIMS elemental signatures in identifying sporulation medium. Theoretical calculations based on the number and density of spores in an analysis area indicate an analytical sample size of about 1 ng, making this technique an attractive method for bioforensics applications.
Importance of Organosulfur Utilization for Survival ofPseudomonas putidain Soil and Rhizosphere
Authors: Mirleau Pascal , Wogelius Roy , Smith Andrew , Kertesz Michael A. 
Published: November 2005

ABSTRACTThe sulfur present in both agricultural and uncultivated soils is largely in the form of sulfonates and sulfate esters and not as free, bioavailable inorganic sulfate. Desulfurization of the former compounds in vitro has previously been studied inPseudomonas putida, a common rhizosphere inhabitant. Survival ofP. putidastrains was now investigated in three sulfur-deficient Danish soils which were found to contain 60 to 70% of their sulfur in sulfonate or sulfate ester form, as determined by X-ray near-edge spectroscopy. The soil fitness ofP. putidaS-313 was compared with that of isogenic strains with mutations in thesftRandasfAgenes (required for in vitro desulfurization of sulfate esters and arylsulfonates, respectively) and in thessulocus (required in vitro for the desulfurization of both sulfonates and sulfate esters).asfAorsftRmutants showed significantly reduced survival compared to the parent strain in bulk soil that had been enriched with carbon and nitrogen to mimic rhizosphere conditions, but this reduced survival was not observed in the absence of these additives. In a tomato rhizosphere grown in compost, survival ofsftRandssumutants was reduced relative to the parent strain. The results demonstrate that the ability to desulfurize sulfonates and sulfate esters is critical for survival of bacteria in the rhizosphere but less so in bulk soils outside the influence of plant roots, where carbon is the limiting nutrient for growth.
Impact of Different In Vitro Electron Donor/Acceptor Conditions on Potential Chemolithoautotrophic Communities from Marine Pelagic Redoxclines
Authors: Labrenz Matthias , Jost Günter , Pohl Christa , Beckmann Sabrina , Martens-Habbena Willm , Jürgens Klaus 
Published: November 2005

ABSTRACT

Anaerobic or microaerophilic chemolithoautotrophic bacteria have been considered to be responsible for CO
2
dark fixation in different pelagic redoxclines worldwide, but their involvement in redox processes is still not fully resolved. We investigated the impact of 17 different electron donor/acceptor combinations in water of pelagic redoxclines from the central Baltic Sea on the stimulation of bacterial CO
2
dark fixation as well as on the development of chemolithoautotrophic populations. In situ, the highest CO
2
dark fixation rates, ranging from 0.7 to 1.4 μmol liter
−1
day
−1
, were measured directly below the redoxcline. In enrichment experiments, chemolithoautotrophic CO
2
dark fixation was maximally stimulated by the addition of thiosulfate, reaching values of up to 9.7 μmol liter
−1
CO
2
day
−1
. Chemolithoautotrophic nitrate reduction proved to be an important process, with rates of up to 33.5 μmol liter
−1
NO
3
−
day
−1
. Reduction of Fe(III) or Mn(IV) was not detected; nevertheless, the presence of these potential electron acceptors influenced the development of stimulated microbial assemblages. Potential chemolithoautotrophic bacteria in the enrichment experiments were displayed on 16S ribosomal complementary DNA single-strand-conformation polymorphism fingerprints and identified by sequencing of excised bands. Sequences were closely related to chemolithoautotrophic
Thiomicrospira psychrophila
and
Maorithyas hadalis
gill symbiont (both
Gammaproteobacteria
) and to an uncultured nitrate-reducing
Helicobacteraceae
bacterium (
Epsilonproteobacteria
). Our data indicate that this
Helicobacteraceae
bacterium could be of general importance or even a key organism for autotrophic nitrate reduction in pelagic redoxclines.
Bacteria Associated with Spores of the Arbuscular Mycorrhizal Fungi
Glomus geosporum
and
Glomus constrictum
Authors: Roesti David , Ineichen Kurt , Braissant Olivier , Redecker Dirk , Wiemken Andres , Aragno Michel 
Published: November 2005

ABSTRACT

Spores of the arbuscular mycorrhizal fungi (AMF)
Glomus geosporum
and
Glomus constrictum
were harvested from single-spore-derived pot cultures with either
Plantago lanceolata
or
Hieracium pilosella
as host plants. PCR-denaturing gradient gel electrophoresis analysis revealed that the bacterial communities associated with the spores depended more on AMF than host plant identity. The composition of the bacterial populations linked to the spores could be predominantly influenced by a specific spore wall composition or AMF exudate rather than by specific root exudates. The majority of the bacterial sequences that were common to both
G. geosporum
and
G. constrictum
spores were affiliated with taxonomic groups known to degrade biopolymers (
Cellvibrio
,
Chondromyces
,
Flexibacter
,
Lysobacter
, and
Pseudomonas
). Scanning electron microscopy of
G. geosporum
spores revealed that these bacteria are possibly feeding on the outer hyaline spore layer. The process of maturation and eventual germination of AMF spores might then benefit from the activity of the surface microorganisms degrading the outer hyaline wall layer.