bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photoperiodic and endocrine control of seasonal breeding in Grey partridge (Perdix perdix)
Authors: Sharp P. J. , Massa R. , Bottoni L. , Lucini V. , Lea R. W. , Dunn I. C. , Trocchi V. 
Published: March 2011

Seasonal changes in gonad weights, concentrations of plasma luteinizing hormone (LH), prolactin, thyroxine (T4) and triiodothyronine (T3), and 5β reductase activity in the neuroendocrine tissues were measured in the Grey partridge (Perdix perdix) in northern Italy. Seasonal changes in the birds' photoperiodic responses were investigated by transferring groups from natural to continuous lighting during most months of the year, and measuring the effect on gonadal weight and plasma LH. The role of increasing short daylengths in stimulating reproductive function in late winter was assessed by measuring testes weight and plasma LH in birds maintained on a fixed short daylength (9 h light: 15 h darkness) during January and February.Egg laying occurred between mid‐April and the end of June, coinciding with seasonally high concentrations of plasma LH and prolactin in both sexes and low plasma T3 in the females. In July, the gonads began to regress and plasma LH levels decreased but plasma prolactin levels remained elevated, falling during August and September. No changes in plasma T3 and T4 were seen in July. In the hyperstriatum (part of the forebrain) and anterior pituitary gland, 5β reductase activity was higher in July than in November, February or May.Plasma LH levels increased after transfer to continuous light between October and April but did not increase after transfer to continuous light between June and September. The increase in plasma LH seen after transfer to continuous light in January, February, March and April was associated with an increase in gonadal size. In contrast, gonadal size did not increase, or did not increase greatly, after transfer to continuous light in October, November and December. Plasma LH levels increased and the testes grew in January and February, irrespective of whether the birds were exposed to natural lighting or to a fixed short daylength.The major conclusions were that in the Grey partridge: 1, seasonal breeding is terminated by the development of long‐day refractoriness; 2, the development of long‐day refractoriness is associated with an increase in plasma prolactin and no change in plasma thyroid hormones; 3, increased 5β reductive activity in the hyperstriatum of long‐day refractory birds may be related to the disappearance of sexual behaviour; and 4, the growth of the testes in late winter is independent of increasing daylength.
Scanning electron microscopy of the accessory respiratory organs of the Snake‐headed fish, Channa striata (Bloch) (Channidae, Channiformes)
Authors: Hughes G. M. , Munshi J. S. D. 
Published: March 2011

The accessory organs of this swamp‐living fish have been studied using SEM and light microscopy.Accessory organs are found in the suprabranchial chambers, labyrinthine plates on the first epibranchial, and roof of the buccopharynx. In these regions, there are nodules of respiratory islets each consisting of many vascular papillae. Non‐respiratory ‘lanes’ separate the islets and are covered with microridged epithelial cells. The dome‐shaped papillae have a smooth surface with band‐like structures running over them. Microvilli are present only at the base of the papillae. The vascular papillae of the buccopharynx are lodged in cup‐like receptacles into which they can retract.The intraepithelial capillaries contain unicellular valves which project into the lumen of the papillae.Capillaries supplying the papillae have an undulatory path which represents a second stage in the evolution of this type of structure.
The Arctic Warbler Phylloscopus borealis– three anciently separated cryptic species revealed
Authors: ALSTRÖM PER , SAITOH TAKEMA , WILLIAMS DAWN , NISHIUMI ISAO , SHIGETA YOSHIMITSU , UEDA KEISUKE , IRESTEDT MARTIN , BJÖRKLUND MATS , OLSSON URBAN 
Published: March 2011

The Arctic Warbler Phylloscopus borealis breeds across the northern Palaearctic and northwestern‐most Nearctic, from northern Scandinavia to Alaska, extending south to southern Japan, and winters in Southeast Asia, the Philippines and Indonesia. Several subspecies have been described based on subtle morphological characteristics, although the taxonomy varies considerably among different authors. A recent study (T. Saitoh et al. (2010) BMC Evol. Biol. 10: 35) identified three main mitochondrial DNA clades, corresponding to: (1) continental Eurasia and Alaska, (2) south Kamchatka, Sakhalin and northeast Hokkaido, and (3) most of Japan (Honshu, Shikoku, Kyushu). These three clades were estimated to have diverged during the late Pliocene to early Pleistocene (border at c. 2.6 million years ago). Differences in morphometrics have also been reported among members of the three clades (T. Saitoh et al. (2008) Ornithol. Sci.7: 135–142). Here we analyse songs and calls from throughout the range of the Arctic Warbler, and conclude that these differ markedly and consistently among the populations representing the three mitochondrial clades. Kurile populations, for which no sequence data are available, are shown to belong to the second clade. To determine the correct application of available scientific names, mitochondrial DNA was sequenced from three name‐bearing type specimens collected on migration or in the winter quarters. Based on the congruent variation in mitochondrial DNA, morphology and vocalizations, we propose that three species be recognized: Arctic Warbler Phylloscopus borealis (sensu stricto) (continental Eurasia and Alaska), Kamchatka Leaf Warbler Phylloscopus examinandus (Kamchatka (at least the southern part), Sakhalin, Hokkaido and Kurile Islands), and Japanese Leaf Warbler Phylloscopus xanthodryas (Japan except Hokkaido).
Influence of background on image recognition in normal vision and age‐related macular degeneration
Authors: Bordier Cécile , Petra Julie , Dauxerre Catherine , Vital‐Durand François , Knoblauch Kenneth 
Published: March 2011

Citation information: Bordier C, Petra J, Dauxerre C, Vital‐Durand F & Knoblauch K. Influence of background on image recognition in normal vision and age‐related macular degeneration. Ophthalmic Physiol Opt 2011, 31, 203–215. doi: 10.1111/j.1475‐1313.2011.00820.xAbstractPurpose:  The influence of background attenuation on the spatial frequency bandwidth requirements for image recognition was assessed in normal young and older groups and in a group with age‐related macular degeneration (AMD). Bandwidth requirements were also assessed in the visual periphery of young normal observers.Methods:  In Experiment 1, each observer was presented with 20 series of images. Each series consisted of a sequence of progressively low‐pass filtered images, presented in an order of increasing bandwidth, i.e., according to an ascending method of limits. For half of the series, the background of the base image was selectively darkened by 80% of its original luminance. Three measures were analyzed: (1) the critical bandwidth defined as the bandwidth in cycles/image (cpi) at which 50% of the images were recognized, (2) the minimal bandwidth, defined as the minimal bandwidth at which images were recognized and (3) the proportion of images recognized at full bandwidth. In Experiment 2, young normal observers were similarly tested in central vision and at 5.5° eccentricity (superior or inferior visual field). A third background attenuation condition was included, as well, in which the background was low‐pass filtered.Results:  The critical bandwidth for image recognition was significantly reduced by darkening the image background for normal young and old and the AMD groups. This improvement was found to be contrast dependent for the darkened background. In addition, AMD observers tended to recognize more images at full bandwidth if the background was darkened. For normal young observers, making the background low‐pass was ineffective in lowering the critical bandwidth in the fovea. Fewer images were recognized at full bandwidth at 5.5° eccentricity for a low‐pass background and marginally fewer for a darkened background.Conclusions:  Selective attenuation of the image background can lead to reductions in the bandwidth requirements for image recognition in AMD. However, performance of young normal observers for images presented in the periphery was unlike AMD performance under the conditions investigated. These results have interesting implications for the design of image enhancement algorithms to aid low vision observers.
The effects of visual degradation on face discrimination
Authors: McCulloch Daphne L , Loffler Gunter , Colquhoun Kirsty , Bruce Natalie , Dutton Gordon N , Bach Michael 
Published: March 2011

Citation information: McCulloch DL, Loffler G, Colquhoun K, Bruce N, Dutton GN & Bach M. The effects of visual degradation on face discrimination. Ophthalmic Physiol Opt 2011, 31, 240–248. doi: 10.1111/j.1475‐1313.2011.00828.xAbstractPurpose:  People with reduced visual acuity (VA) and/or contrast sensitivity have difficulty recognizing faces and facial expressions. We have quantified these difficulties, using a synthetic face discrimination task employing both normal and artificially degraded vision.Methods:  VA and contrast thresholds were measured using an optimised staircase procedure [Freiburg acuity Test (FrACT)] in 25 young adults (aged 18–24 years) with corrected visual acuity of 0.0 logMAR or better and with four levels of vision degraded with Bangerter occlusion foils. For face discrimination, male face images were synthesised from 37 cardinal points (position of eyes, width of nose, head shape etc) derived from frontal face photographs and manipulated by altering the points as a fraction of the mean head radius. Face discrimination thresholds (% difference) were measured from a simultaneous four‐alternative forced choice of ‘odd one out’ from three identical faces and one that differed. Psychometric functions were measured for four participants with normal and degraded vision. Subsequently, the difference between faces was fixed at twice the discrimination thresholds and the size of the faces manipulated using the FrACT threshold procedure in 25 participants. Data were converted to equivalent face discrimination distances for realistic face dimensions.Results:  With normal vision, face discrimination thresholds ranged from 2.7% to 5.6%; these increased systematically and were more variable with visual degradation. When manipulating face size, face discrimination distance was highly correlated with both acuity and contrast sensitivity (r2 = 0.77 and 0.80 respectively, p < 0.01). The mean distance with normal vision was 15.3 m (14.5–16.2 ± S.E.M.). With vision degraded to 0.6 logMAR (6/24 Snellen, contrast threshold 15%) the mean face discrimination distance was reduced to 3.9 m (3.7–4.1, ±S.E.M.).Conclusions:  Poor face discrimination has a profound impact on real‐life social communication. Here we report that artificial visual degradation also adversely impacts a synthetic face recognition task. As a rule of thumb, reduction in VA of 0.3 logMAR (halving the decimal VA) reduces the face recognition distance by a factor of 0.6 times. The FrACT‐based face discrimination task provides an efficient new tool to quantify and monitor face discrimination ability.
Incremental segmentation of lidar point clouds with an octree‐structured voxel space
Authors: Wang Miao , Tseng Yi‐Hsing 
Published: March 2011

AbstractLidar (light detection and ranging) data implicitly contains abundant three‐dimensional spatial information. The segmentation of lidar point clouds is the key procedure for transforming implicit spatial information into explicit spatial information. Common criteria used for point cloud segmentation are proximity and coherence of point distribution. An effective segmentation algorithm may apply various steps or combinations of criteria depending on the application. This paper proposes a four‐step segmentation method for lidar point clouds to deliver incremental segmentation results. Segmentation results of each step can provide the fundamental data for the next step. In the first step, the input point cloud is organised into an octree‐structured voxel space, in which the point neighbourhood is established. In the second step, connected voxels which are not empty are grouped to obtain grouped points based on proximity. The third step is a coplanar point segmentation based on both coherence and proximity, which was performed on each point group obtained in the second step. Finally, neighbouring coplanar point groups are merged into “co‐surface” point groups based on the criteria of plane connection and intersection. This scheme enables an incremental retrieval and analysis of a large lidar data‐set. Experimental results demonstrate the effectiveness of the segmentation algorithm in handling both airborne and terrestrial lidar data. It is anticipated that the incremental segmentation results will be useful for object modelling using lidar data.
Land and Water Institutions in the Blue Nile Basin: Setups and Gaps for Improved Land and Water Management
Authors: Hagos Fitsum , Haileslassie Amare , Awulachew Seleshi Bekele , Mapedza Everisto , Taffesse Tesfaye 
Published: March 2011

AbstractThis study undertook an assessment and gap analysis of the institutional arrangements for improved land and water management in the Tana and Beles Sub‐basins highlands of the Blue Nile Basin. We explored the mandates and design features of the major land‐ and water‐related institutional arrangements. Focus group discussions, key informant interviews, and a literature review were used in the analysis.The results of our work reveal that a lot of progress has been made in creating an institutional framework for improved land and water management and the policies and laws hitherto developed reflect global policy changes consistent with the widespread adoption of the integrated water resources management (IWRM) principles. There are also cases where informal institutions replace formal institutions. Judged by their enforcement, the water resources management, pollution control standards, and regulations and land use rights are not enacted effectively because of poor enforcement capacity. Overall there is a tendency to focus on command‐and‐control type policies. There is a need to strengthen traditional institutions by drawing lessons from their strengths and establish the legitimacy of these institutions. There is also a need to improve formal policy design, developing policies with specific objectives, goals, targets, and overall institutional changes and resources through active adaptive management to maximize the level and effectiveness of institutional learning. Finally, more focus needs to be given to incentive‐based policies through increased use of positive incentives and more emphasis needs to be given to self‐enforcement rather than third‐party enforcement.
Socio‐economic Considerations in Biosafety and Biotechnology Decision Making: The Cartagena Protocol and National Biosafety Frameworks
Authors: Falck‐Zepeda Jose Benjamin , Zambrano Patricia 
Published: March 2011

AbstractArticle 26.1 of the Cartagena Protocol on Biosafety left open the possibility for member countries to include in their biosafety regulatory processes the assessment of socio‐economic considerations. Countries may also decide to include such assessments as part of their national legislation or regulations for the approval and deliberate release into the environment of genetically engineered technologies. Countries are debating if and how to implement assessment of socio‐economic considerations. This paper contributes to the ongoing policy dialogue by discussing issues related to socio‐economic assessment including scope, timing, inclusion modalities, methods, decision‐making rules and standards, and the integration of socio‐economic assessments in biosafety and/or biotechnology approval processes. This paper also discusses the implications of such inclusion for technology flows and public and private sector R&D. If inclusion is not done properly, it may negatively impact technology flows especially from the public sector and render an unworkable biosafety system.
The expansion of social care and reform: Implications for care workers in the Republic of Korea
Authors: PENG Ito 
Published: March 2011

Abstract.A falling fertility rate, increasing longevity, government “social investment” strategies to achieve the transformation from industrial to post‐industrial economy, and increased state support to help women balance family and work responsibilities – all these influences have produced mixed results for the poorly paid female care workers in low‐status jobs in the Republic of Korea. The author summarizes policy changes and reports on interviews with childcare and elder‐care workers, policy experts and researchers, showing that though increased regulation and expansion of public childcare have led to some improvements, the deregulation and marketization of elder‐care have resulted in worsening conditions for elder‐care workers.
Care arrangements and bargains: Anganwadi and paid domestic workers in India
Authors: PALRIWALA Rajni , NEETHA N. 
Published: March 2011

Abstract.This article explores state and social understandings of care work in India by examining two categories of non‐family care workers – hired domestic workers and Anganwadi Workers/Helpers under the Integrated Child Development Scheme. Classified as “volunteers” in a government programme, the Anganwadi Workers/Helpers enjoy some social standing and relatively extensive unionization compared with domestic workers. Also, domestic workers have to make much harder trade‐offs between their family's livelihood and daily care needs. The economic undervaluation of the care work they perform, however, is common to both categories of workers.
Online discussion boards in dental education: potential and challenges
Authors: Linjawi A. I. , Walmsley A. D. , Hill K. B. 
Published: March 2011

AbstractBackground:  Online discussion boards may enhance critical analysis and reflection, and promote the acquisition of knowledge.Aims:  To assess the effectiveness of online discussion board as a pedagogical tool in augmenting face‐to‐face teaching in dental education.Method:  Data were collected from a discussion archive offered through the E‐course website of the School of Dentistry, University of Birmingham, UK in 2008. A multi‐component metric included; participation, social learning, cognitive processing, role of instructors, and quality of discussion. Messages were coded for 14 variables to evaluate these dimensions. Data were analyzed using content analysis methodology and a complete message was uses as the unit of analysis.Results:  There were no significant difference in participation between students and instructors (P < 0.05). Social interaction with peers appeared only through students posting messages with open questions (27/135 messages). The discussion board was mainly used by students to understand concepts (27/102 messages) and apply procedural knowledge (17/102 messages). Instructors were mainly replying to students’ messages with (49/120 messages) or without (54/120 messages) proposing another action.Conclusions:  Online discussion boards were found to be successful pedagogical tools in dental education. Further development of instructor‐led discussion approach is needed to promote higher level learning and collaborative thinking.
A Double‐Blind Randomized Controlled Trial (RCT) of Titanium‐13Zirconium versus Titanium Grade IV Small‐Diameter Bone Level Implants in Edentulous Mandibles – Results from a 1‐Year Observation Period
Authors: Al‐Nawas Bilal , Brägger Urs , Meijer Henny J.A. , Naert Ignace , Persson Rigmor , Perucchi Alessandro , Quirynen Marc , Raghoebar Gerry M. , Reichert Torsten E. , Romeo Eugenio , Santing Hendrik J. , Schimmel Martin , Storelli Stefano , Bruggenkate Christiaan ten , Vandekerckhove Betty , Wagner Wilfried , Wismeijer Daniel , Müller Frauke 
Published: March 2011

ABSTRACTBackground: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two‐implant overdenture has been recommended as the standard of care. The use of small‐diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable.Purpose: This randomized, controlled, double‐blind, multicenter study investigated in a split‐mouth model whether small‐diameter implants made from Titanium‐13Zirconium alloy (TiZr, Roxolid™) perform at least as well as Titanium Grade IV implants.Methods and Materials: Patients with an edentulous mandible received one TiZr and one Ti Grade IV small‐diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double‐blinded. Outcome measures included change in radiological peri‐implant bone level from surgery to 12 months post‐insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary).Results: Of 91 treated patients, 87 were available for the 12‐month follow‐up. Peri‐implant bone level change (−0.3 ± 0.5 mm vs −0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices.Conclusion: This study confirms that TiZr small‐diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations.