bluuebunny/crossref_metadata_2025_split huggingface dataset:
The distribution of the logarithm in an orthogonal and
a symplectic family of L-functions
Authors: Hough Bob 
Published: March 2012

Abstract
We consider the logarithm of the central value

log
L
(
1
/
2
)

$\log L(1/2)$

in the orthogonal
family

{
L

(
s
,
f
)

}

f
∈

H
k

$\lbrace L(s,f)\rbrace _{f \in H_k}$

where Hk
is the set of weight k Hecke-eigen
cusp forms for

SL
2

(
ℤ
)

$\text{SL}_2(\mathbb {Z})$

, and in the symplectic family

{
L

(
s
,

χ

8
d

)

}

d
≍
D

$\lbrace L(s,\chi _{8d})\rbrace _{d
\asymp D}$

where

χ

8
d

$\chi _{8d}$

is the real character associated to fundamental
discriminant

8
d

$8d$

. Unconditionally, we prove that the two distributions are
asymptotically bounded above by Gaussian distributions, in the first case of
mean

-
1
/
2
log
log
k

$-1/2 \log \log k$

and variance

log
log
k

$\log \log k$

, and in the second case of
mean

1
/
2
log
log
D

$1/2\log \log D$

and variance

log
log
D

$\log \log D$

. Assuming both the Riemann and
Zero Density Hypotheses in these families we obtain the full normal law in both
families, confirming a conjecture of Keating and Snaith.
Efficiency Enhancement in Hybrid P3HT/Silicon Nanocrystal Solar Cells
Authors: Niesar Sabrina , Fabian Wolfgang , Petermann Nils , Herrmann Daniel , Riedle Eberhard , Wiggers Hartmut , Brandt Martin S. , Stutzmann Martin 
Published: March 2012

AbstractHybrid organic-inorganic solar cells from poly(3-hexylthiophene) (P3HT) and freestanding silicon nanocrystals (Si-ncs) combine the advantages of silicon-based photovoltaics with the cost-efficient solution processing technique. At present, the microwave-plasma synthesis of Si-ncs that allows for a future upscaling to industrial demands is at the expense of the Si-nc surface quality and the number of charge-trapping defects. Here, we present an enhancement of the solar cell performance by identifying the major factors which are limiting the device efficiency. With the help of low-cost post-growth treatments of the Si-ncs and the optimization of various device parameters, P3HT:Si-ncs bulk heterojunction solar cells with an efficiency up to 1.1% are achieved. In particular, etching of the Si-ncs with hydrofluoric acid to remove the surface oxide shells and surface defects has a strong impact on the solar cell performance. An intermediate Si weight ratio of around 60% is found to lead to the highest current densities. For Si-ncs with very small diameters, an additional enhancement of the open circuit voltage was observed. Moreover, we show that the structural order of P3HT has a strong influence on the efficiency, which can be explained by an improved charge carrier separation at the P3HT/Si-ncs interface in combination with an enhanced charge transport in the P3HT phase.
Synthesis, regiochemistry and molecular structure of spiro[2,2′]indane-1′,3′-dione-pyrrolizidine compounds
Authors: Chen Gang , Gu Xuefan , Ma Chao 
Published: March 2012

Abstract
Spiro[2,2′]indane-1′,3′-dione-3-methoxycarbonyl-3-methylpyrrolizidine (compound A) and spiro[2,2′]indane-1′,3′-dione-3-(o-chlorophenyl)-4-nitropyrrolizidine (compound B) were synthesized by 1,3-dipolar cycloaddition with different regioselectivity. The two compounds were characterized by NMR, MS and single-crystal X-ray diffraction data. Compound A crystallizes in the monoclinic space group, P2(1)/n, with unit cell dimensions a=10.204(6) Å, b=14.888(9) Å, and c=10.750(6) Å, α=90.00° β=95.081(6)°, γ=90.00° and Z=4. Compound B crystallizes in the triclinic space group, P-1, with unit cell dimensions a=7.6074(4) Å, b=9.7454(5) Å, and c=12.6538(7) Å, α=85.313(2)°, β=84.217(2)°, γ=86.571(2)° and Z=2.
Fast and efficient method for the synthesis of 2-arylbenzimidazoles using MCM-41-SO3H
Authors: Mahdavinia Gholam Hossein , Rostamizadeh Shahnaz , Amani Ali Mohammad , Sepehrian Hamid 
Published: March 2012

Abstract
Nanosized MCM-41-SO3H material based on ordered mesoporous silica gel with covalently attached sulfonic acid groups was synthesized and used as acid catalyst for green synthesis of 2-substituted benzimidazole derivatives. Echo-friendly protocol, short reaction times, easy and quick isolation of the products, and excellent yields are the main advantages of this procedure.
On Product Difference Fibonacci Identities
Authors: Melham R. S. 
Published: March 2012

AbstractSimson's identity is a well-known Fibonacci identity in which the difference of certain order 2 products has a particularly pleasing form. Other old and beautiful identities of a similar nature are attributed to Catalan, Gelin and Cesàro, and Tagiuri. Catalan's identity can be described as a family of
Centralizers of subgroups in simple locally finite groups
Authors: Ersoy Kıvanç , Kuzucuoğlu Mahmut 
Published: March 2012

AbstractHartley asked the following question: Is the centralizer of every finite subgroup in a simple non-linear locally finite group infinite? We answer a stronger version of this question for finite 𝒦-semisimple subgroups. Namely letMoreover we prove that if
Correlation of Cyr61 and CTGF in placentas from the late pre-eclamptic pregnancy
Authors: Chen Xi , Liu Yanyan , Xu Xiaoyan , Chen Hanping 
Published: March 2012

Abstract
It is thought that a shallow invasion of the maternal decidua by extravillous trophoblasts (EVT) is associated with the development of pre-eclampsia. Here, we focus on the expression of the proangiogenic proteins Cyr61 and CTGF in the human placenta during normal pregnancy compared with that in the late pre-eclamptic placenta. Cyr61 and CTGF are expressed in the extravillous trophoblast and in endothelial cells. We found the expression of Cyr61 was significantly decreased in pre-eclamptic placentas compared with matched controls. In contrast, the CTGF expression level was upregulated in pre-eclamptic placentas. There was a negative correlation between Cyr61 and CTGF. These results suggest that decreased Cyr61 and overexpressed CTGF may play a part in the development of pre-eclampsia.
Multifunctionalized carbon nanotubes as advanced multimodal nanomaterials for biomedical applications
Authors: Lamanna Giuseppe , Battigelli Alessia , Ménard-Moyon Cécilia , Bianco Alberto 
Published: March 2012

AbstractThe increasing importance of nanotechnology in the field of biomedical applications has encouraged the development of new nanomaterials endowed with multiple functions. Novel nanoscale drug delivery systems with diagnostic, imaging and therapeutic properties hold many promises for the treatment of different types of diseases, including cancer, infection and neurodegenerative syndromes. Functionalized carbon nanotubes (CNTs) are one of the most recent type of nanomaterial developed in biomedicine as they can be designed and imparted with multimodal capabilities. Indeed, the possibility of inserting different functionalities on CNTs is opening the possibility to exploit them on new strategies that combine diagnosis with improved therapeutic efficacies. In this review, we describe the different approaches that have been recently developed to generate multifunctionalized CNTs for biomedical applications. In particular, covalent and non-covalent double and triple functionalization methods are discussed, putting in evidence their use in vitro and in vivo and highlighting the advantages and the drawbacks of these new systems. Preclinical studies have demonstrated that multifunctional CNTs are highly promising when combining diagnostic, imaging and therapeutic modalities.
Nobel Prize awards in Radiochemistry
Authors: Adloff J.-P. 
Published: March 2012

AbstractIn 1996 the Editors of Radiochimica Acta brought out a special volume of the journal to celebrate the hundredth anniversary of the discovery of radioactivity [1]. On the occasion of the 50thanniversary of Radiochimica Acta, which follows closely upon the centenary of Marie Curie’s second Nobel Prize in 1911, the author has the privilege to informally review “Radiochemistry and Nobel Prize Awards”, including discoveries of radioelements and new fields in chemistry based on radiochemical methods.
Dark‐Field Microscopic Monitoring of Subgingival Bacteria During Periodontal Therapy
Authors: Singletary Macon M. , Crawford James J. , Simpson David M. 
Published: March 2012

The purpose of this study was to explore the application of microscopic evaluation of the sulcular flora to aid diagnosis and to evaluate progress of treatment during initial (presurgical) periodontal therapy. Fifteen adult patients with clinical diagnosis of moderate to severe periodontitis were used. Two contralateral healthy sulci and two contralateral periodontal pockets were chosen for examination in each patient. Clinical and microbiological assessments of these sites were made at four separate appointments, as follows: (1) at the inception of therapy, prior to plaque control instructions; (2) 2 weeks following plaque control instruction; (3) 2 weeks following supragingival scaling; and (4)4 weeks following root planing of diseased sites. Initial therapy was completed in 10 to 12 weeks.Clinical features monitored during the study were the Gingival Index, Plaque Index and gingival fluid flow. The bacterial examination consisted of dark‐field microscopic counting of morphologic forms and culturing of samples using a medium selective for Bacteroides species. Subgingival bacterial samples were obtained with a sterile curette from each site at each of the four appointments. The samples were placed immediately after procurement into anaerobic transport medium from which agar plate cultures were established. Microscopic counting was performed within 1 hour. One hundred microorganisms were evaluated in random microscopic fields and categorized on the basis of cell morphology and motility.Based on paired t tests, significant differences in subgingival flora were found when healthy sites were compared with diseased sites at the inception and completion of the experimental period. Significant changes were also found in intragroup samples, both healthy and diseased, between the beginning and end of initial therapy. Coccoid cells dominated the healthy sites at the initial appointment (62.3% vs. 18.3%), while total motile organisms dominated the diseased sites (43.7% vs. 4.8%). In the diseased sites between appointments No. 1 and No. 4 there was a reduction in the number of motile organisms, 43.7% to 14.0%, and an increase in coccoid cells from 18.3% to 41.5%. Counts of colonies grown on medium largely selective for Bacteroides species dropped markedly in both the healthy and diseased sites, especially at the end of initial therapy. High proportions of coccoid cells correlated with health and motile forms with disease. Discriminant analysis using coccoid cells and total motile organisms suggested that these bacterial categories were reliable for classifying healthy and diseased sites, respectively.Microscopic evaluation of subgingival flora was found to be an accurate and convenient means to evaluate the presumptive activity of periodontal lesions and to monitor progress of therapy.
Comparison of Hypertonic Saline and Chlorhexidine Mouthrinses After the Inverse Bevel Flap Procedure
Authors: Newman P. S. , Addy M. 
Published: March 2012

The value of periodontal dressings after periodontal surgery has been questioned. This study further evaluated chlorhexidine as a possible alternative. A group of nine patients requiring comparable bilateral inverse bevel flap procedures underwent preoperative oral hygiene instruction and scaling. Immediately before surgery and up to 3 months postoperatively, clinical records of plaque index, pocket depths and sulcus bleeding index were made. Records were taken of patients' postoperative discomfort and preferences. During the 1st postoperative week either a 0.2% chlorhexidine gluconate or a 1% saline mouthrinse was prescribed.Plaque accumulation and sulcus bleeding were significantly reduced on the sides treated with chlorhexidine. Significant reductions in pocket depths were recorded for both groups but there were no differences between treatments.Less postoperative discomfort was experienced with chlorhexidine, although the difference was not significant. Five patients preferred chlorhexidine, one saline, and three had no preferences. These and previous results suggest that a periodontal dressing is unnecessary or even undesirable after the inverse bevel flap procedure, and may be usefully replaced by a suitable antiplaque agent.
Ultrastructural Study of New Connective Tissue Attachment Following Phosphoric Acid Application on Human Root Dentin
Authors: Heritier M. 
Published: March 2012

The present study was undertaken to verify whether acid conditioning of the root surface can promote new connective tissue attachment in man.A flap was raised over two maxillary central incisors, with 6‐mm pockets, which had to be extracted in a 72‐year‐old woman. Following root planing, a rectangular area was delineated by a groove on the buccal surface of the teeth. Inside these limits, cementum was removed and the denuded dentin was etched with a 50% gelified phosphoric acid solution (pH, 1.3) for 1 minute and the flap was repositioned. Forty‐two days later, the experimental teeth were extracted, and undecalcified specimens were prepared routinely for transmission electron microscopy.Results showed that new connective tissue attachment had occurred between healing connective tissues and acid‐treated dentin surface, with functionally oriented Sharpey's fibers. The mechanism of new connective tissue attachment could be observed as a typical cementum crystallites deposition on a denuded dentin matrix coupled with an active collagen fibrils synthesis. This process resulted in the incorporation of fibers into the new superficial layer of cementoïd tissue.
Caries Levels in Patients With Juvenile Periodontitis
Authors: Fine D. H. , Goldberg D. , Karol R. 
Published: March 2012

The degree and distribution of tooth decay in a group of juvenile periodontitis (JP) patients were compared with tooth decay in an age‐ and sex‐matched periodontally normal control group. The experimental group was comprised of 13 patients of no more than 20 years of age who were designated as localized juvenile periodontitis patients (LJP) according to the definition of Baer, and 10 patients of no more than 25 years of age who were designated as generalized juvenile periodontitis patients (GJP), as described by Manson and Lehner. Twenty‐three age‐ and sex‐matched patients with no periodontal disease served as the control group. Caries was evaluated by standard clinical and radiographic criteria and quantitated by decayed, missing, filled teeth and surfaces (DMFS). Decay was further categorized as active proximal decay and as total proximal decay, which included both active proximal caries and restored proximal surfaces.A Student's t test revealed no statistical differences between the LJP and GJP groups. Moreover, there was no difference in the number of missing or filled teeth in the JP group as compared to the control group. However, 17 of the 23 JP patients had no proximal decay, whereas all but two of the 23 control patients had some proximal decay. Moreover, in the JP group (LJP and GJP) the mean values for active proximal decay and total proximal decay were both significantly lower than those in the control group (P < 0.001). Thus, a low number of proximal carious lesions were found in the presence of juvenile periodontitis. Furthermore, this unusual pattern of proximal dental disease was significantly different from that of the matched control group. The bacteriologic and immunologic significance of these findings deserves further attention.
Transmission and Colonization of Actinobacillus actinomycetemcomitans in Localized Juvenile Periodontitis Patients
Authors: Christersson Lars A. , Slots Jørgen , Zambon Joseph J. , Genco Robert J. 
Published: March 2012

Actinobacillus Actinomycetemcomitans is a Gram‐negative oral microorganism, which has been implicated in the etiology of localized juvenile periodontitis and in severe medical infections such as bacterial endocarditis. This study evaluated the ability of periodontal probes to transmit A actinomycetemcomitans from juvenile periodontitis lesions to healthy gingival sulci in the same patient.Localized juvenile periodontitis patients exhibiting first molar and incisor alveolar bone loss and with large numbers of A actinomycetemcomitans in deep periodontal pockets were included in this study. A periodontal probe was inserted into periodontal pockets of 6 mm or greater depth. The probe was then placed into a healthy gingival sulcus of 3 mm or less, in the same subject. Fifty‐five transfers by probing were made and A actinomycetemcomitans in both the donor and recipient sites was assessed by a selective culture technique.The results indicate that periodontal probes can become contaminated with A actinomycetemcomitans from juvenile periodontitis lesions during routine dental examinations and can transfer this microorganism from infected to previously uninfected sites. However, A actinomycetemcomitans inoculated into the healthy gingival sulci did not permanently colonize these sites since the organisms were eliminated within 3 weeks.
Effects of Scaling and Root Planing on Subgingival Microbial Proportions Standardized in Terms of Their Naturally Occurring Distribution
Authors: Hinrichs James E. , Wolff Larry F. , Pihlstrom Bruce L. , Schaffer Erwin M. , Liljemark William F. , Bandt Carl L. 
Published: March 2012

This investigation included A cross‐sectional component (284, 20–40‐year‐old subjects/568 sites) and a longitudinal component (19 subjects with moderate to advanced periodontitis/76 sites). Subgingival plaque samples and clinical data were obtained from all upper second bicuspids and first molars in the longitudinal subjects and from both upper first molars in the cross‐sectional subjects. The purpose was to: (1) determine/confirm changes in proportions of selected subgingival microorganisms following root planing combined with conventional oral hygiene procedures in the longitudinal subjects, (2) evaluate those changes in terms of an estimate of the naturally occurring distribution of subgingival microorganisms based on data obtained from the cross‐sectional subjects and (3) relate shifts in the subgingival microorganisms to changes in clinical measurements.Changes following treatment at sites with pre‐instrumentation probing depths ≥4.5 mm included cocci, 18.3 to 46.9%; spirochetes, 20.9 to 3.1%; total motile organisms, 28.5 to 5.9%; Fusobacterium spp., 10.2 to 2.2%; and dark‐pigmented Bacteroides spp., 14.0 to 9.7%. Translating proportions of microorganisms in samples from subjects in the longitudinal treatment study to equivalent percentile ranks within the large cross‐sectional data base demonstrated that at probing depths ≥4.5 mm cocci moved from below the 50th percentile in our estimate of the naturally occurring distribution of subgingival microorganisms to above, and spirochetes, total motile organisms and Fusobacterium spp. moved from above the 50th percentile to below. The microbiological findings were consistent with statistically significant improvements in clinical measurements. Statistically significant changes also occurred in microorganisms at sites with initial probing depths <4.5 mm.
Relationship of Maxillary Molar Root Angulation and Palatal Vault Height
Authors: Howell Monroe M. , Cassingham R. Jack , Yukna Raymond A. 
Published: March 2012

If the vertical angulation of maxillary molar roots could be reliably predicted, this might affect the choice of root(s) to retain in root resection procedures. In an attempt to develop this prediction, angulation of palatal roots was compared to palatal vault height. Human cadaveric maxillae with molars were sectioned faciopalatally through each tooth root to the palatal midline and photographed. Root angles and palatal height were measured on the photographs in relation to a reference line connecting buccal and palatal cementoenamel junctions (CEJ). Palatal vault heights were classified as low, medium, or high according to the perpendicular distance from the midpalatal suture to the reference line. Root angles were subtended by a line following the length of pulp canals and perpendicular to the CEJ reference.Analysis by Spearman's Rank Correlation Coefficient demonstrated a weak and nonsignificant relationship between palatal vault height and the angulation of the various maxillary molar roots. Thus, palatal vault height would not be a reliable predictor of root angulation if this were to be used as a basis for root retention.
Bioceramic Implants in Surgical Periodontal Defects: A Comparison Study
Authors: Barney Vermon C. , Levin Marvin P. , Adams Donald F. 
Published: March 2012

The healing response of two commercially available bioceramics, beta tricalcium phosphate (TCP) and hydroxylapatite (HA), was compared after implantation in surgically created defects in dogs.Three 18 to 24 month old female Labrador dogs were used. Under general anesthesia 3wall defects were created on the canines and premolars. The roots were planed, and reference notches were placed to identify the alveolar crest and the apical extent of the defects. TCP or HA was placed in alternating canine defects. The premolars received no implants and served as controls. Plaque management was accomplished by biweekly brushing with 0.2% Chlorhexidine. Following healing periods of 5, 12 and 16 weeks, the dogs were sacrificed and perfused with 10% formalin. Six‐μ step serial sections were evaluated by light microscopy.Healing against the root planed surface varied from a long junctional epithelium to a connective tissue reattachment in new cementum. TCP particles were actively resorbed by giant cells and macrophages and were incorporated into new bone matrix. The HA particles were encapsulated by fibrous connective tissue and rarely seen in contact with repairing bone. Bone formation was slower around HA particles at all time periods. Some evidence of HA particle resorption was seen at each time period.
Effect of Metronidazole on Development of Subgingival Plaque and Experimental Periodontitis
Authors: Polson Alan M. , Zappa Urs E. , Espeland Mark A. , Eisenberg Arthur D. 
Published: March 2012

Active tissue destruction in experimental periodontitis has been positively correlated with subgingival spirochetes and total number of organisms. The present study was designed to inhibit spirochete populations and evaluate the effect upon periodontal destruction. Metronidazole was administered orally to four squirrel monkeys (100 mg/kg/bwt) for 17 days, After 3 days, marginal periodontitis was induced around bicuspids and molars by tying silk ligatures at the gingival margins. Subgingival plaque samples were taken baseline and 14 days after ligature placement. Dark‐field microscopy quantitated motile forms, spirochetes, straight and curved rods, filaments, cocci and fusiforms. Periodontal destruction was evaluated at 2 weeks by histometric analysis of connective tissue attachment, crestal alveolar bone and infiltrated connective tissue. Bacterial and histometric comparisons were made with experimental periodontitis data from four animals (control) which had not received metronidazole.Subgingival plaque prior to periodontitis induction was dominated by cocci, but fusiforms and straight rods were also present. Straight rods formed a greater proportion of the plaque which developed in metronidazole‐receiving animals. The absence of spirochetes and motile rods contrasted with the control group where spirochetes were the predominant type. The total number of bacteria was also larger in the control animals. Histometric analysis showed that areas of infiltrated supracrestal connective tissue were similar in both groups. Loss of connective tissue attachment and alveolar bone was significantly less in experimental animals, and the latter values did not differ significantly from baseline dimensions. The results indicated that the subgingival bacterial populations which developed during metronidazole administration did not result in an experimental periodontitis.