bluuebunny/crossref_metadata_2025_split huggingface dataset:
Treatment of Circumferential Defects with Osseoconductive Xenografts of Different Porosities: A Histological, Histometric, Resonance Frequency Analysis, and Micro‐CT Study in Dogs
Authors: Antunes Antonio Azoubel , Grossi‐Oliveira Gustavo Augusto , Martins‐Neto Evandro Carneiro , De Almeida Adriana Luisa Gonçalves , Salata Luiz Antonio 
Published: November 2013

AbstractBackgroundFinding the most effective method of minimizing the gap effect in alveolar crest remodeling constitutes a clinical challenge for immediate implant technique.PurposeTo evaluate the effectiveness of osseoconductive xenografts with different porosities in the crestal bone region, with and without guided bone regeneration, over immediate implant installation.Materials and MethodsFive bone defects (6 mm in diameter/4 mm depth) were prepared on one side of the mandibles of twelve dogs. Implants of 3.3 × 10 mm were installed on the mesial side of each defect, providing a 2.7‐mm distal gap. Defects were randomly filled with autogenous bone, coagulum, a deproteinized bovine bone mineral (DBBM) block, a DBBM sponge, or DBBM granules. The same procedures were performed on the opposite side after 8 weeks. Collagen membranes were used to cover the defects on half of the sides. The animals were sacrificed after 8 weeks. The outcomes were evaluated by histology, histomorphometric analysis, resonance frequency analysis, and micro‐CT analysis.ResultsThe histomorphometry showed the DBBM sponge to provide similar bone formation to autogenous bone at 8 weeks without a membrane. The coagulum rendered better bone formation at 16 weeks (membrane) (p < .05). The DBBM block exhibited the poorest results between treatments (8 and 16 weeks, with or without membrane). Micro‐CT analysis revealed increasing bone surface values in sites with DBBM granules, followed by the DBBM sponge (8 weeks without membrane) and autogenous bone at 8 weeks with membrane (p < .05). Porosity analysis of the biomaterials showed the highest number, volume, and surface area of closed pores in DBBM granules. The DBBM block presented the highest volume of open pores, open porosity, and total porosity.ConclusionsThe high‐porosity block (DBBM block) failed to provide greater bone repair within the defect. Biomaterials with lower porosity (DBBM sponge and granules) showed similar or higher bone formation when compared with autogenous bone.
A systematic review to assess cost effectiveness of enhanced recovery after surgery programmes in colorectal surgery
Authors: Lemanu D. P. , Singh P. P. , Stowers M. D. J. , Hill A. G. 
Published: November 2013

AbstractAimEnhanced recovery after surgery (ERAS) programmes have been shown to reduce length of stay and peri‐operative morbidity. However, there are comparatively few data on their cost effectiveness. The object of this systematic review was to appraise the current literature to determine the cost effectiveness of ERAS and to characterize how cost is reported and evaluated.MethodAn electronic database search identified studies comparing ERAS with standard peri‐operative care in colorectal surgery where an evaluation of cost effectiveness was a primary or secondary outcome. Cost data were converted to euros to enable a more standardized comparison of the studies. There were no limits on study design.ResultsSeven articles were included in the analysis. The reporting and evaluation of cost data were inconsistent. Reported cost for ERAS ranged from €1989 to €12 805 per patient. Although not all statistically significant, all studies demonstrated cost reductions with ERAS compared with non‐ERAS although they were highly variable, ranging from €153 to €6537 per patient.ConclusionAlthough the review has shown ERAS to be cost effective, there are some important inconsistencies and deficiencies regarding the reporting of data. Authors should therefore be encouraged to report cost data to supplement the literature detailing clinical efficacy.
Fiddling in biodiversity hotspots while deserts burn? Collapse of the Sahara's megafauna
Authors: Durant S. M. , Wacher T. , Bashir S. , Woodroffe R. , De Ornellas P. , Ransom C. , Newby J. , Abáigar T. , Abdelgadir M. , El Alqamy H. , Baillie J. , Beddiaf M. , Belbachir F. , Belbachir‐Bazi A. , Berbash A. A. , Bemadjim N. E. , Beudels‐Jamar R. , Boitani L. , Breitenmoser C. , Cano M. , Chardonnet P. , Collen B. , Cornforth W. A. , Cuzin F. , Gerngross P. , Haddane B. , Hadjeloum M. , Jacobson A. , Jebali A. , Lamarque F. , Mallon D. , Minkowski K. , Monfort S. , Ndoassal B. , Niagate B. , Purchase G. , Samaïla S. , Samna A. K. , Sillero‐Zubiri C. , Soultan A. E. , Stanley Price M. R. , Pettorelli N. 
Published: November 2013

AbstractBiodiversity hotspots understandably attract considerable conservation attention. However, deserts are rarely viewed as conservation priority areas, due to their relatively low productivity, yet these systems are home to unique species, adapted to harsh and highly variable environments. While global attention has been focused on hotspots, the world's largest tropical desert, the Sahara, has suffered a catastrophic decline in megafauna. Of 14 large vertebrates that have historically occurred in the region, four are now extinct in the wild, including the iconic scimitar‐horned oryx (Oryx dammah). The majority has disappeared from more than 90% of their Saharan range, including addax (Addax nasomaculatus), dama gazelle (Nanger dama) and Saharan cheetah (Acinonyx jubatus hecki) – all now on the brink of extinction. Greater conservation support and scientific attention for the region might have helped to avert these catastrophic declines. The Sahara serves as an example of a wider historical neglect of deserts and the human communities who depend on them. The scientific community can make an important contribution to conservation in deserts by establishing baseline information on biodiversity and developing new approaches to sustainable management of desert species and ecosystems. Such approaches must accommodate mobility of both people and wildlife so that they can use resources most efficiently in the face of low and unpredictable rainfall. This is needed to enable governments to deliver on their commitments to halt further degradation of deserts and to improve their status for both biodiversity conservation and human well‐being. Only by so‐doing will deserts be able to support resilient ecosystems and communities that are best able to adapt to climate change.
Attitudes towards e‐learning amongst dental students at the universities in Croatia
Authors: Brumini G. , Špalj S. , Mavrinac M. , Biočina‐Lukenda D. , Strujić M. , Brumini M. 
Published: November 2013

AbstractAimTo develop and test the psychometric characteristics of a questionnaire that measures attitudes towards e‐learning, as well as to study attitudes about e‐learning and to identify variables related to those attitudes amongst dental students.Subject and MethodsThe study was conducted from November 2010 to December 2011 at all three Croatian dental schools. A questionnaire entitled ‘Attitude Towards e‐Learning’ consisting of 12 questions about socio‐demographic data and 22 statements about attitude towards e‐learning was self‐administered by 386 students. Factorial analysis and Cronbach's alpha were used to test the psychometric characteristics of the questionnaire. Multiple regression analysis was used to identify variables related to attitudes towards e‐learning.ResultsFactorial analysis confirmed two factors: positive attitude and negative attitude, which interpret 58% of the total variance and had good internal consistency of α = 0.852 and 0.668, respectively. The average score of positive attitude was 42 ± 6, indicating a highly positive attitude towards e‐learning. The average score of negative attitude was 27 ± 6, indicating minor negative attitude. Higher age and study year, usage of the Internet in education, more frequent usage of Facebook and more attendance of e‐courses demonstrated a significant influence on positive attitude towards e‐learning (R2 = 0.304; P < 0.001). Lower year of study and less frequent attendance of e‐courses had a significant influence on negative attitude (R2 = 0.268; P < 0.001).ConclusionsDental students have generally positive attitudes towards e‐learning. Teachers should adopt strategies to change negative attitudes by introducing more e‐learning courses in lower study years and should encourage students to use the Internet in their education and communication with teachers and colleagues.
History of the invasive African olive tree in Australia and Hawaii: evidence for sequential bottlenecks and hybridization with the Mediterranean olive
Authors: Besnard Guillaume , Dupuy Jérémy , Larter Maximilien , Cuneo Peter , Cooke David , Chikhi Lounes 
Published: November 2013

AbstractHumans have introduced plants and animals into new continents and islands with negative effects on local species. This has been the case of the olive that was introduced in Australia, New Zealand and Pacific islands where it became invasive. Two subspecies were introduced in Australia, and each successfully invaded a specific area: the African olive in New South Wales (NSW) and the Mediterranean olive in South Australia. Here, we examine their origins and spread and analyse a large sample of native and invasive accessions with chloroplast and nuclear microsatellites. African olive populations from the invaded range exhibit two South African chlorotypes hence supporting an introduction from South Africa, while populations from South Australia exhibit chlorotypes of Mediterranean cultivars. Congruently, nuclear markers support the occurrence of two lineages in Australia but demonstrate that admixture took place, attesting that they hybridized early after introduction. Furthermore, using an approximate Bayesian computation framework, we found strong support for the serial introduction of the African olive from South Africa to NSW and then from NSW to Hawaii. The taxon experienced successive bottlenecks that did not preclude invasion, meaning that rapid decisions need to be taken to avoid naturalization where it has not established a large population yet.
Freeze tolerance and physiological changes during cold acclimation of giant reed [Arundo donax (L.)]
Authors: Pompeiano A. , Vita F. , Miele S. , Guglielminetti L. 
Published: November 2013

AbstractArundo donax L. (Poaceae), giant reed, is a rhizomatous shrubby grass that is cultivated in subtropical and warm temperate regions for a multitude of uses. Recently, it has been identified as a leading sustainable, non‐food crop for lignocellulosic biofuels due to its low ecological and agronomic demands. Lack of cold hardiness may limit its diffusion into colder areas of the transition zone. The objectives of this study were to (i) quantify freeze tolerance (LT50) of cold‐acclimated and non‐acclimated Arundo donax L. plants using reproducible, controlled environment conditions, (ii) determine the effect of prolonged exposure to freeze stress on tolerance by keeping plants at a constant, sublethal temperature and (iii) study the relationship of non‐structural carbohydrates (total soluble sugars, glucose, fructose and sucrose) and proline accumulation with cold hardiness. In vitro‐propagated plants of the Honduran and Hungarian ecotypes of Arundo donax L. were chosen for this study. Cold acclimation treatment was imposed for 1 week using a controlled environment chamber set at 10°C and with a 12‐h photoperiod of 200 μmol m−2 s−1 photosynthetically active radiation. Freeze tolerance ranged from −12·8°C (Honduran) to −16·4°C (Hungarian ecotype). In all the organs analysed, total soluble sugars significantly increased during cold acclimation, with concentrations between 1·8‐ and 4·7‐fold higher than in non‐acclimated plants. The higher concentrations of sugars and proline in cold‐acclimated plants were positively associated with enhanced giant reed freeze tolerance (2·9°C lower). Our results confirm that during cold acclimation, metabolic changes related to increased freezing tolerance occur in giant reed.
Effect of feed space allowance and period of access to food on dairy cow performance
Authors: Ferris C. P. , Patterson D. C. , Mayne C. S. , O'Connell N. E. 
Published: November 2013

AbstractTwo experiments were conducted to examine the ‘long‐term’ effect of feed space allowance and period of access to feed on dairy cow performance. In Experiment 1, three horizontal feed space allowances (20, 40 and 60 cm cow−1) were examined over a 127‐d period (14 cows per treatment). In Experiment 2, 48 dairy cows were used in a continuous design (10‐week duration) 2 × 2 factorial design experiment comprising two horizontal feed space allowances (15 and 40 cm cow−1), and two periods of access to feed (unrestricted and restricted). With the former, uneaten feed was removed at 08·00 h, while feeding took place at 09·00 h. With the latter, uneaten feed was removed at 06·00 h, while feeding was delayed until 12·00 h. Mean total dry‐matter (DM) intakes were 19·0, 18·7 and 19·3 kg cow−1 d−1 with the 20, 40 and 60 cm cow−1 treatments in Experiment 1, and 18·1 and 18·2 kg cow−1 d−1 with the ‘restricted feeding time’ treatments, and 17·8 and 18·1 kg d−1 with the ‘unrestricted feeding time’ treatments (15 and 40 cm respectively) in Experiment 2. None of milk yield, milk composition, or end‐of‐study live weight or condition score were significantly affected by treatment in either experiment (P > 0·05), while fat + protein yield was reduced with the 15‐cm treatment in Experiment 2 (P < 0·05). When access to feed was restricted by space or time constraints, cows modified their time budgets and increased their rates of intake.
Musculoskeletal disorders amongst Greek endodontists: a national questionnaire survey
Authors: Zarra T. , Lambrianidis T. 
Published: November 2013

AbstractAimTo investigate amongst Greek endodontists the prevalence and characteristics of musculoskeletal disorders (MSDs) in the past 12 months, the treatment followed, their postures during practice and the adoption of ergonomic standards.MethodologyOne hundred and forty‐seven endodontists met the inclusion criteria and were invited to participate in the survey. Participants were asked for personal/professional data, prevalence, characteristics and treatment for MDSs in the past 12 months. Endodontists' postures during practice as well as ergonomic factors were also recorded. Data were analysed using chi‐square test, independent samples t‐test and logistic regression. The level of significance was set at P = 0.05.ResultsThe response rate was 84%. MSDs were reported by 61% of the participants. Of them, 69% reported pain to more than one body part. The prevalence of disorders was highest in the lower back (30%) and neck (30%). Medical care was applied in 53% of the disorders. A sitting position was always used by 83% of endodontists. Awkward postures during practice (OR:4.561, 95% CI:1.341–15.512), regular stretching exercises (OR:0.032, 95% CI:0.010–0.110) and number of patients day−1 (OR:3.524, 95% CI:1.686–18.100) were significant predictors for MSDs. Properly adjusted stools, sufficient lighting and space in the operating room were reported by 71%, 96% and 93% of participants, respectively.ConclusionsA high percentage of endodontists reported MSDs. Adoption of correct/neutral postures, regular performance of stretching exercises and reduced number of patients/day were associated with a low prevalence of disorders. The majority of endodontists had adopted ergonomic innovations/standards to control disorders.
Keratocystic odontogenic tumour arising as a periapical lesion
Authors: Santos J. N. , Carneiro Júnior B. , Alves Malaquias P. D. T. I. , Henriques Á. C. G. , Cury P. R. , Rebello I. M. C. R. 
Published: November 2013

AbstractAimTo document a case of a keratocystic odontogenic tumour (KOT) involving the apical region in the maxilla mimicking a periapical lesion of endodontic origin.SummaryBenign and malignant tumours, including odontogenic lesions, can be erroneously diagnosed as periapical radiolucencies. KOTs mimicking periapical lesions of endodontic origin are uncommon, especially when the lesions involve the maxilla. This article describes a 55‐year‐old man with a well‐delimited, oval‐shaped, radiolucent lesion, occupying the middle and apical third of teeth 22 and 23. After 30 days, the clinical and radiographic findings remained unchanged and the patient was referred for surgical removal of the lesion. Clinical, radiographic and histopathological features are also discussed and compared with current literature.
Human acellular dermal wound matrix: evidence and experience
Authors: Kirsner Robert S , Bohn Greg , Driver Vickie R , Mills Joseph L , Nanney Lillian B , Williams Marie L , Wu Stephanie C 
Published: November 2013

AbstractA chronic wound fails to complete an orderly and timely reparative process and places patients at increased risk for wound complications that negatively impact quality of life and require greater health care expenditure. The role of extracellular matrix (ECM) is critical in normal and chronic wound repair. Not only is ECM the largest component of the dermal skin layer, but also ECM proteins provide structure and cell signalling that are necessary for successful tissue repair. Chronic wounds are characterised by their inflammatory and proteolytic environment, which degrades the ECM. Human acellular dermal matrices, which provide an ECM scaffold, therefore, are being used to treat chronic wounds. The ideal human acellular dermal wound matrix (HADWM) would support regenerative healing, providing a structure that could be repopulated by the body's cells. Experienced wound care investigators and clinicians discussed the function of ECM, the evidence related to a specific HADWM (Graftjacket® regenerative tissue matrix, Wright Medical Technology, Inc., licensed by KCI USA, Inc., San Antonio, TX), and their clinical experience with this scaffold. This article distills these discussions into an evidence‐based and practical overview for treating chronic lower extremity wounds with this HADWM.
Field and Frequency Dependence of the Dynamic Hysteresis in Lead Zirconate Titanate Solid Solutions
Authors: Chen Xuefeng , Dong Xianlin , Cao Fei , Wang Junxia , Wang Genshui 
Published: November 2013

Dynamic hysteresis of Nb‐doped Pb(Zr1−xTix)O3 (PZT, 0.20 ≤ x ≤ 0.60) ceramics were studied systemically at different field (E) and frequency (f). The hysteresis loops were strongly dependent on E and f. The measured coercive fields (Ec0) were far lower than the calculated values based on the Landau–Ginzburg theory, and increased dramatically from the rhombohedral phase to the tetragonal phase while had less variation with composition in the same phase. With increasing E or f for each composition, three types of loops were observed: linear, minor, and saturated loops. The cross fields (E0), cross polarizations (P0), and hysteresis areas (<A>) showed different variation regularities with f. Similar varying curves were observed for all PZT ceramic samples by normalizing E0, P0, and <A> with E/Ec0, which indicated the same polarization switching for different domain structures. Further analyses revealed that the switching processes can be divided into three stages: space charge polarization, domain switching, and steady state. The first and second stage occurred at ~0.5 and ~1.5 E/Ec0, respectively. These results would be very helpful to further understand the polarization switching of ferroelectric ceramics.
Solid Solutions of Lead Metaniobate—Stabilization of the Ferroelectric Polymorph and the Effect on the Lattice Parameters, Dielectric, Ferroelectric, and Piezoelectric Properties
Authors: Sahini Mtabazi G. , Grande Tor , Fraygola Barbara , Biancoli Alberto , Damjanovic Dragan , Setter Nava 
Published: November 2013

Ferroelectric orthorhombic lead metaniobate (PbNb2O6) is known to be metastable with respect to the thermodynamically stable nonferroelectric rhombohedral polymorph. The high‐temperature tetragonal to low temperature rhombohedral phase transition is reconstructive and thereby sluggish; ferroelectric PbNb2O6 is obtained by quenching from the stable phase field of the tetragonal polymorph. We report on the stabilization of the ferroelectric tungsten bronze polymorphs of PbNb2O6 by minor chemical substitution in the series [(1 − x) PbNb2O6–xBiTiNbO6], [(1 − x)PbNb2O6–xNa0.5Bi0.5Nb2O6], [(1 − x)PbNb2O6–xK0.5Bi0.5Nb2O6], and [(1 − x)PbNb2O6–xCaTiO3]. The high‐temperature tungsten bronze polymorph is entropy stabilized with respect to the stable rhombohedral polymorph, and we propose that the tungsten bronze is further entropy stabilized by chemical substitution, reducing the transition temperature of the rhombohedral polymorph and further disfavoring the kinetics of the undesired phase transition. Optimized solid‐state synthesis and processing to obtain dense ceramics were developed for the solid solutions, and the dielectric, ferroelectric, and piezoelectric properties of the PbNb2O6 solid solutions are reported. Curie temperature is suppressed with chemical substitution in all the systems. Lattice cell parameters display systematic variation with composition, reducing the molar volume, and the lattice parameter ratio 2b/a with increasing degree of substitution, reflecting a suppression of the polarization along the (010) direction due to chemical substitution. The piezoelectric properties improved with increasing substitution level probably due to the ease of poling of the materials with lower Tc. However, some improvements seen with 2% CaTiO3 were not accompanied by Tc decrease.
Determining the Kinetic Parameters for Isothermal Crystallization in a Lithium Disilicate (Ls2) Glass by OM and DSC
Authors: Everton Leyliane S. , Cabral Aluisio A. 
Published: November 2013

It is well known that the variation in the crystallized fraction, x(t), can be determined directly by optical microscopy (OM) or indirectly by differential scanning calorimetry (DSC) under isothermal conditions. In this work, the kinetic crystallization parameters E (activation energy) and n (Avrami index) of a quasi‐stoichiometric lithium disilicate glass (Li2O·2SiO2–LS2) were studied. First, bulk samples were heat treated in a vertical tube furnace between 500°C and 530°C for different periods of time, and were carefully prepared. Furthermore, the same samples were then heated in a calorimeter from room temperature to 850°C at 10°C/min. The following E and n values were obtained: (i) OM: 462.2 ± 1.23 kJ/mol and 4; and (ii) DSC: 187.5 ± 0.45 kJ/mol and 2.4. The results indicated that the activation energy was reduced due to the formation of new crystals and growing of the “preexisting crystals” during the DSC experiments, and that the predominant crystallization mechanism in the samples changed according to the chosen thermal history.
Photocatalytic Activity of Novel Ag4V2O7 Photocatalyst Under Visible Light Irradiation
Authors: Wang Jinxiu , Yang Xue , Chen Jing , Xian Jiangjun , Meng Sugang , Zheng Yi , Shao Yu , Li Danzhen 
Published: November 2013

In this study, pure Ag4V2O7 was synthesized via hydrothermal method without surfactant at different temperatures (100°C, 120°C, and 140°C) and pH values (4 and 5) for the first time. Moreover, Ag4V2O7 nanoparticles with homogeneous size distribution about 200–300 nm can be obtained by adding polyvinylpyrrolidone to the synthesis system. Effects of hydrothermal synthesis conditions on photophysical properties and photocatalytic activity of Ag4V2O7 were investigated systematically. Ag4V2O7 sample prepared at 120°C and pH = 4 had the optimal photocatalytic activity among these samples, which almost completely degraded 10 ppm Rhodamine B within 3 h under visible light irradiation (420 nm < λ < 800 nm). The degradation products were measured by liquid chromatography–mass spectroscopy. The active species involved in the degradation process were analyzed by means of adding active species scavengers, electron spin resonance techniques, and photoelectrochemical experiments. A possible mechanism for photocatalytic degradation of organic pollutants on Ag4V2O7 photocatalyst was proposed and discussed preliminarily.