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Search Results: 1 - 10 of 8616 matches for " primary cavity excavators "
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Influence of potential cavity resources on secondary cavity-nesters and breeding bird community composition
潜在洞巢资源差异对次级洞巢鸟及繁殖鸟类群落的影响

Daqing Zhou,Chunfa Zhou,Wenhong Deng,
周大庆
,周春发,邓文洪

生物多样性 , 2009,
Abstract: To explore how density of potential cavity resources (including cavities and artificial nest boxes) affects the composition and distribution of secondary cavity-nesting guilds, as well as the community structure of breeding birds, we studied plots with different densities of nest cavities in Dagang Forestry Farm, Jilin Province, China from November 2007 to July 2008. Based on the density of cavity resources, the nine sample sites were divided into three treatments, i.e., NBP (nest-box plots with less cavities and high-density nest boxes), LDP (low-density cavities plots without nest boxes) and HDP (high-density cavities plots without nest boxes). We then surveyed avian communities and noted the use of cavities and artificial nest boxes. All the treatments contained four primary cavity excavators, and three species were the same. Four secondary cavity nesters were widespread in the three treatments, including the great tit {Parus major), marsh tit (P. palustris), yellow-rumped flycatcher (Ficedula zanthopygia) and eurasian nuthatch (Sitta europaea). Total densities of secondary cavity nesters in NBP and HDP were higher than that of LDP. Densities of great tits and yellow-rumped flycatchers were higher in NBP and HDP than in LDP, because they were major users of nest boxes. There were no significant differences in the densities of marsh tits and eurasian nuthatches among treatments. A significant positive correlation was detected between the density of primary cavity excavators and cavity density, and also between the density of secondary cavity nesters and potential cavity resources. Bird species diversity indices were lower in LDP than in NBP and HDP. Nest-box addition could potentially regulate the composition of avian communities by increasing bird species diversity indices. We observed no differences in evenness, species richness indices or probability of interspecific encounter (PIE) among treatments, and Serensen similarity indices differed little among treatments. There were no obvious differences in structure of breeding bird guilds between HDP and LDP. Nine species were found in all the three treatments, and their densities were not affected by the temporary increase in secondary cavity nesters. We hypothesize that density of primary cavity excavators determines the density of cavities in forests, which may change distributional patterns of secondary cavity-nester guilds, and therefore affect the structure of breeding avian communities.
Validation and Comparison of Calibration Techniques for Measurements of Carbon Dioxide in Atmospheric Air Standards  [PDF]
Andreia de Lima Fioravante, Cristiane Rodrigues Augusto, Valnei Smar?aro da Cunha, Luiz Antonio d’Avila
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.91004
Abstract: The increase in the concentration of carbon dioxide (CO2) in the atmosphere has led the scientific community to investigate the adverse effects on humanity and nature, including the greenhouse effect, which contributes to global warming and can lead to climate change, besides the risks associated with human health. Due to the importance of metrological issues in the current scenario, the Laboratory of Gas Analysis (Lanag) of the National Institute of Metrology, Quality and Technology (Inmetro) is developing the methodology of preparation of such primary standard gas mixtures through gravimetry. For the preparation of these standards, an analysis verification step is necessary, carried out by means of an analytical technique of comparison, at low levels of concentration, by cavity ringdown (CRDS) and by gas chromatography using a flame ionization detector coupled to a methaniser catalyst (GC-FIDmeth). This work presents the method validation of both methodologies developed to analyze a range of concentration of atmospheric standards of CO2 at a matrix of synthetic clean dry air (SCDA) by CRDS and GC-FIDmeth, of which the analysis results can compromise the measurements on atmospheric air quality. The objective is to compare results of method validation of both analytical methods for low CO2 concentration through the use of primary reference mixtures developed and also by certified reference material. The validation measurement results were analyzed according to the requirements of ISO 5725: 1994 parts 1 and 2, and the calculation of measurement uncertainty followed the methodology described in ISO 6143:2001, with results showing satisfactory consistent between both selected techniques. According to the work presented here, the obtained validation results for CRDS are better than the GC results, such as the relative uncertainty of samples evaluated for CRDS was 0.4% and 2.7% for GC_FID meth.
2D Part-Based Visual Tracking of Hydraulic Excavators  [PDF]
Bo Xiao, Ruiqi Chen, Zhenhua Zhu
World Journal of Engineering and Technology (WJET) , 2016, DOI: 10.4236/wjet.2016.43C013
Abstract:
Visual tracking has been widely applied in construction industry and attracted signifi-cant interests recently. Lots of research studies have adopted visual tracking techniques on the surveillance of construction workforce, project productivity and construction safety. Until now, visual tracking algorithms have gained promising performance when tracking un-articulated equipment in construction sites. However, state-of-art tracking algorithms have unguaranteed performance in tracking articulated equipment, such as backhoes and excavators. The stretching buckets and booms are the main obstacles of successfully tracking articulated equipment. In order to fill this knowledge gap, the part-based tracking algorithms are introduced in this paper for tracking articulated equipment in construction sites. The part-based tracking is able to track different parts of target equipment while using multiple tracking algorithms at the same sequence. Some existing tracking methods have been chosen according to their outstanding performance in the computer vision community. Then, the part-based algorithms were created on the basis of selected visual tracking methods and tested by real construction sequences. In this way, the tracking performance was evaluated from effectiveness and robustness aspects. Throughout the quantification analysis, the tracking performance of articulated equipment was much more improved by using the part-based tracking algorithms.
Carcinoma escamocelular bucal diagnosticado precozmente
Napier de Souza,Leandro; Albuquerque de Brito,Ant?nio; Rodrigues Antunes de Souza,Ana Cristina; Santiago Gomez,Ricardo; da Costa Reis,Patrícia Maria; López Alvarenga,Rodrigo;
Revista Cubana de Estomatolog?-a , 2010,
Abstract: the squamocellular carcinoma is a malignant neoplasm commonest in the buccal cavity. the more frequently involved anatomical sites are the lower lip, the tongue's lateral edges and the mouth floor. its etiology is multifactor although it is closely related to smoking and alcoholism. clinical picture is generally characterized by the presence of different types of white, erythematous, between erythematous and white plaques, ulcers with raised edges and exophytic masses. treatment includes surgical removal, radiotherapy, chemotherapy or both. in present paper the case of a man aged 70 presenting with buccal squamous carcinoma describing the clinical, and the histopathologic findings and its corresponding treatment. the early and appropriate diagnosis allowed the cure of this case.
Tumor neuroectodérmico primitivo de maxilar: Presentación de un caso
Pe?a Sevilla,Lourdes; Pi?ate,Lilibeth; Granados,María; López,Alfonso; Sánchez,Claudia; Morao,Elien; Arteaga,Reina; Rojas,Nilda; Gómez,Ruth;
Revista Venezolana de Oncología , 2006,
Abstract: periferical neroectodermic primary tumor is a part of the sarcoma ewing family and represents 5 % of them. the superior maxillary location is not frequent, we report these clinical case of a male teenage of 15 years old sent to our hospital with loss weigh, tumor in the oral cavity in the left superior quadrant of the oral cavity, with a diameter of 6 cm, that it occupies 50 % of the same one with sobreinfection, with necrosis. the biopsy reported: tumor of undifferentiated round cells. we observed a growth of the tumor that triples its size in 8 days, it occupies it in totality, with tendency to obstruction of the air way, needed emergency traqueostomy and gastrostomy. the inmunohistoquimical studies reveal primary neuroectodermic tumor (inmunoreactive to cd99 enolasa neurospecific and cromagine), received two cycles of ciclofosfamide, vincristine, actinomicyn d, ifosfamida and etoposid, with disease progression and depletory of his physical status; receive radiation therapy 6 000 cgy with platinum, obtaining favorable condition to surgery: a bilateral maxilectomy with preservation of the floor of the orbit. the anatomopathological study report fibromixoide weave a lot of vascularization without evidence of malignity, free margins. actually, 7 months without evidence of disease waiting for platinum prosthesis to restituted the functional deglution. in the inusual localizations, the treatment has to be multidisciplinary, individualized, and include the three treatment modalities (quemotherapy, radiation therapy and surgery).
Microleakage study of simplified adhesive systems in class V cavities of primary teeth
Shiva Mortazavi,Anahita Haratian,Mehrdad Kazemian,Pouran Samimi
Journal of Isfahan Dental School , 2011,
Abstract: Introduction: There is a high demand for tooth-colored restorations in pediatric dentistry. Since etch-and-rinse adhesive systems are time-consuming, there is a tendency to replace them with simplified adhesive systems. This study compared microleakage of class V composite resin restorations in primary teeth restored using simplified adhesive systems.Materials and Methods: In this in vitro study standard class V cavities were prepared in 60 primary canines with incisal margins in enamel and gingival margins in dentin. The samples were randomly divided into 4 groups and restored as follows: Group 1: Opti Bond Solo Plus (OBP); Group 2: Clearfil SE Bond (SEB); Group 3: Clearfil S3 Bond (S3B); Group 4: Xeno IV (XeIV). The cavities were filled with Filtek Z250 composite resin and observed under a stereomicroscope at × 32 for microleakage scoring. The results were analyzed with Kruskal-Wallis test followed by Mann-Whitney and Wilcoxon Signed Rank tests using SPSS software.Results: The results showed significant differences between groups 1 and 4 and group 3 in enamel leakage (p value = 0.005). There was also a significant difference between group 1 and groups 2 and 4 in dentinal leakage (p value = 0.001). The test showed that enamel leakage in groups 1 and 4 was significantly lower than dentinal leakage in these groups.Conclusion: The strong acidic adhesives in groups 1 and 4 were more effective in enamel leakage prevention. The mild self-etching adhesive in group 3 was effective in enamel and was the best in dentin leakage prevention. Key words: Microleakage, Simplified adhesives, Self-etching adhesive, Cervical cavity, Primary teeth.
Numerical modelling of excavator capacity
G. Y. Bulatov,A. A. Terekhov
Magazine of Civil Engineering , 2011,
Abstract: Caused by the general development of technical progress the necessity of forecasting of technological processes demands estimation of communications between parameters of these processes. However the process can proceed in various modes, and search of area of the defining parameters answering to an optimum mode of course of technological process is represented rather important. These problems were to some extent covered in all list of references. Optimization of technological processes carries essential economic benefit at least because it doesn't demand any additional capital investments for realization. So, for example, only at the expense of change of bottom width developed by excavator on some meters, it is possible to increase productivity of digging cars essentially. Considering enormous volumes of digging works (according to academician A. L. Janshin these volumes in the world make nearby 60 km3/year (volumes of volcanic activity – 16)), cumulative effect of optimization will be considerable. And it is easily reached, not including expenses for statement of a problem and the corresponding calculations. The calculation example for excavator "front shovel" is given in the article.
Cavernous Hemangioma of the Nasal Cavity  [PDF]
Peter Kalina, Jeffrey Rykken
Open Journal of Medical Imaging (OJMI) , 2011, DOI: 10.4236/ojmi.2011.12007
Abstract: A 22 year old six month pregnant female presented with right eye tearing, proptosis and nasal congestion. CT revealed a large right nasal cavity mass with involvement of the ethmoids, right maxillary sinus, lamina papyracea, cribriform plate and nasal septum. There was significant remodeling of the right cribriform plate with mild extra-axial intracranial and mild intraorbital extension. Transnasal endoscopic excision confirming the diagnosis of cavernous hemangioma of the nasal cavity. Hemangiomas are benign slow-growing vascular neoplasms classified as capillary, cavernous or mixed. Hemangiomas of the nasal cavity and paranasal sinuses are very rare with only a few reported cases. The occurrence and growth of these lesions during pregnancy may be related to increased blood volume or hormonal factors. The most common therapeutic option is complete surgical resection via transnasal endoscopic approach. Pre-operative embolization may be utilized in some cases to decrease the risk of intraoperative bleeding.
Melanoma of the Oral Cavity: About Two Cases and Review of Literature  [PDF]
F. Elomrani, H. Mouzount, I. Ouziane, R. Khmamouch, S. lkhoyali, A. Boukir, M. ElKabous, S. Boutayeb, H. Mrabti, B. Elkhannoussi, H. Errihani
International Journal of Clinical Medicine (IJCM) , 2013, DOI: 10.4236/ijcm.2013.44033
Abstract:

Mucosal malignant melanoma of the oral cavity is an extremely rare condition. It has a poor prognosis. Here we report two typical cases of malignant melanoma. In the first case, 64 years old man developed an exophytic tumor in the hard palate. Head and neck and chest computerized tomography scan showed a large aggressive tumor of the hard palate. The patient also had multiple lung metastases and a cervical lymph node. The second case is a 73 years old woman presenting a burgeoning mass on the right palate. Facial CT reveals a malignant tumor lateralized in the right palate with ipsilateral metastatic lymph nodes. Histological with immunohistochemical studies assigned both cases to a malignant melanoma. Due to the rarity of oral malignant melanomas, case reports are a necessary source of information.

Carcinoma escamocelular bucal diagnosticado precozmente Oral squamocellular carcinoma with early diagnosis
Leandro Napier de Souza,Ant?nio Albuquerque de Brito,Ana Cristina Rodrigues Antunes de Souza,Ricardo Santiago Gomez
Revista Cubana de Estomatolog?-a , 2010,
Abstract: El carcinoma escamocelular es la neoplasia maligna más común en la cavidad bucal. Los sitios anatómicos más frecuentemente afectados son el labio inferior, los bordes laterales de lengua y el suelo de la boca. Su etiología es multifactorial, aunque está íntimamente relacionada con factores ambientales como el tabaquismo y el alcoholismo. El cuadro clínico se caracteriza generalmente por la presencia de placas blancas, placas eritematosas, placas entre eritematosas y blancas, úlceras de bordes levantados y masas exofíticas. El tratamiento consiste en la extirpación quirúrgica, la radioterapia, quimioterapia o ambos tratamientos. Este artículo presenta un caso de carcinoma escamocelular bucal en un paciente del sexo masculino, de 70 a os de edad. En el mismo se describen los hallazgos clínicos, histopatológicos y el tratamiento correspondiente del caso. El diagnóstico precoz y correcto posibilitó la cura en este caso. The squamocellular carcinoma is a malignant neoplasm commonest in the buccal cavity. The more frequently involved anatomical sites are the lower lip, the tongue's lateral edges and the mouth floor. Its etiology is multifactor although it is closely related to smoking and alcoholism. Clinical picture is generally characterized by the presence of different types of white, erythematous, between erythematous and white plaques, ulcers with raised edges and exophytic masses. Treatment includes surgical removal, radiotherapy, chemotherapy or both. In present paper the case of a man aged 70 presenting with buccal squamous carcinoma describing the clinical, and the histopathologic findings and its corresponding treatment. The early and appropriate diagnosis allowed the cure of this case.
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