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1.
Interdisciplinaria ; 37(2): 61-78, dic. 2020. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1149364

ABSTRACT

Resumen A partir de una aproximación orientada a la persona (Conner y Pope, 2013; Schmidt, Rosenberg y Beymer, 2017), este estudio examina perfiles momentáneos de compromiso cognitivo, afectivo y comportamental en estudiantes de secundaria a lo largo de tres sesiones de clases de ciencias. Participaron 53 estudiantes de secundaria colombianos (63 % mujeres, de 9.º a 11.º grado). El método de muestreo de experiencias (Csikszentmihalyi y Larson, 1987; Zuzanek, 1999) se usó para tomar medidas repetidas del compromiso cognitivo (importancia), afectivo (disfrute e interés) y comportamental (concentración y esfuerzo). Se realizó un análisis de agrupamiento o clustering para la identificación de los perfiles. El análisis de agrupamiento permitió identificar cinco perfiles momentáneos de compromiso que se distribuyen en tres tipos por cada sesión: moderado, universalmente bajo, renuente, racional y recreacional. En la primera sesión los estudiantes se distribuyen de la siguiente manera: moderado (43 %), recreacional (32 %) y universalmente bajo (25 %); en la segunda sesión, renuente (44 %), moderado (38 %), y racional (18 %); y, en la tercera sesión, moderado (47 %), racional (32 %) y universalmente bajo (21 %). Los perfiles mostraron permanencia y variación. El perfil más frecuente y permanente fue el compromiso moderado, mientras que el más variable fue el universalmente bajo. Se concluye que los perfiles momentáneos de compromiso plantean preguntas y retos diferenciados para los educadores, quienes deben desarrollar prácticas educativas que promuevan perfiles de compromiso relacionados con mejores procesos de aprendizaje y desempeño en ciencias. Los resultados se discuten en términos de las implicaciones educativas en las interacciones profesor-estudiante.


Abstract Based on a person-oriented approach (Conner y Pope, 2013; Schmidt, Rosenberg y Beymer, 2017), this study examines momentary profiles of cognitive, affective, and behavioral engagement in high school students through three sessions of science classes (e.g. environmental education, biology, chemistry, and physics). A total of 53 Colombian high school students participated in this study (63 % women, 9th to 11th grade). The experience sampling method (ESM; Csikszentmihalyi y Larson, 1987; Zuzanek, 1999) was used to take repeated measures of cognitive engagement (importance), affective engagement (enjoyment and interest) and behavioral engagement (concentration and effort). Through a cellphone alarm, the students were called to answer the Experience Sampling Form (ESF) once in each class throughout the thematic unit studied. In the ESF students reported their thoughts, emotions and efforts at the moment of the signal. A total of 159 students' responses were collected. A clustering analysis was performed to identify the profiles. The cluster analysis allowed the identification of five momentary engagement profiles that were classified into three types for each session: moderate, universally low, reluctant, rational, and recreational. In the first session, the students were distributed as follows: Moderate (43 %), Recreational (32 %) and Universally Low (25 %); in the second session, Reluctant (44 %), Moderate (38 %), and Rational (18 %); and in the third session, Moderate (47 %), Rational (32 %) and Universally Low (21 %). That profiles showed permanence and variation. The most frequent and permanent engagement profile was the moderate, while the most variable was the universally low. When reviewing the profiles by session, we found that the groups that make up these profiles were not the same students. This not only marks a variability in the profiles between sessions, but also allows the description of the oscillations and intraindividual trajectories of engagement. This implies that the same student does not necessarily present the same pattern of engagement throughout the three classes sessions and, although some students tend to have stable profiles over time, others show greater variability. It is concluded that momentary profiles of academic engagement pose different questions and challenges for educators, in terms of educational practices that may promote engagement profiles linked to deep learning processes and performance in sciences. Results are discussed in terms of the educational implications in teacher-student interactions. Future research should combine three elements in the study of engagement: to include multidimensionality of engagement (e.g., cognitive, affective and behavioral), to describe momentary profiles, and to establish relationship among these profiles with the characteristics of educational environments (e.g., educational practices and relationships between teachers and students).

2.
Acta Pharmaceutica Sinica ; (12): 138-143, 2019.
Article in Chinese | WPRIM | ID: wpr-778673

ABSTRACT

Near-infrared spectroscopy (NIRS) combined with chemometrics can achieve rapid detection in process analysis. After variable selection, the redundant information is effectively removed and the characteristic variables related to the response values are selected. Compared with global model, the complexity is significantly reduced and the prediction accuracy is also improved. In this study, near-infrared spectroscopy analysis combined with different variable selection methods was applied to achieve the rapid detection of baicalin in the extraction process of Scutellaria baicalensis. Data sets were divided based on sample set portioning based on joint x-y distance (SPXY) method. Competitive adaptive weighted resampling method (CARS), random frog (RF) and successive projections algorithm (SPA) were applied to variable selection. Partial least squares (PLS) models were constructed based on above three methods, and the prediction results were compared. After CARS, RF and SPA method, 92, 10 and 17 variables were screened out respectively. According to the performance of the models, CARS method is found to be more effective and suitable than RF and SPA. Furthermore, the characteristic variables selected by CARS method have a better correspondence with the chemical structure of baicalin. The root mean square error (RMSEC) of the calibration set and the root mean square error (RMSEP) of the prediction set are 0.528 2 and 0.720 2 respectively. Compared with the global PLS model, the correlation coefficient of the calibration set (Rc) is increased to 0.979 9 from 0.917 0, and the relative standard errors of prediction (RSEP) is reduced to 5.59% from 10.58%.

3.
Chinese Journal of Oncology ; (12): 561-564, 2019.
Article in Chinese | WPRIM | ID: wpr-805780

ABSTRACT

Esophagus, as the pipe connecting oral cavity and stomach, has unique anatomical structure and physiological functions. The related diseases including esophageal cancer and precancerous lesions are the ones of major public health problems in China. The pathogenesis of esophageal diseases is still not clear. The exploration of correlation between the changes of esophageal microbiota and esophageal diseases becomes a new breakthrough in the study of etiology. Previous studies have found enrichment of gram-positive bacteria in the normal esophagus, while a decrease in diversity of bacteria and a dominant gram-negative anaerobe in diseased esophagus. Although much progress has been made in the study of esophageal microbiota, the standard method of how to accurately and noninvasively collect esophageal microbiota is still lack, which is an important part of the esophageal microbial research.

4.
Chinese Journal of Practical Nursing ; (36): 2295-2299, 2019.
Article in Chinese | WPRIM | ID: wpr-803496

ABSTRACT

Objective@#To assess and analyze clinical nursing workload of tertiary general hospitals in Tianjin.@*Methods@#4 tertiary general hospitals in Tianjin were recruited by convenience sampling. 13 representative departments of the medical system and the surgical system were selected as the investigation departments. All the clinical duty nurses of every day work in selected departments were taken as the observation objects. Unified training investigators used work sampling method to observe and record the "operation" , "movement", "waiting" and "others" four types of activities of nurses, taking an observation point in a minute; SPSS17.0 was used for analysis.@*Results@#Totally 172 800 sampling points were selected. Besides 2.62% (4 534/172 800) of other affairs, the total nursing workload in one day was 97.38% (168 264/272800), with 85.03% (146 923/172 800) operating time including direct nursing accounting for 33.64% (58 144/172 800), indirect nursing accounting for 8.92% (15 422/172 800), and 42.46% (73 363/172 800) of related nursing. Movement accounted for 11.71% (20 228/172 800), while waiting accounted for 0.65% (1 113/172 800).@*Conclusion@#Generally, nurses in tertiary general hospitals have long working time and heavy workload, but direct nursing which can reflects the value and connotation of nursing work is low. In nursing work, the "waiting" caused by the lack of personnel, material, equipment, environment problems made a waste of time and human resources to certain extent. Therefore, results of the present study can provide reference for tertiary hospitals to optimize the allocation of nursing human resources, improve the quality of nursing service, reduce the workload of nurses and construct lean management system.

5.
China Journal of Chinese Materia Medica ; (24): 306-308, 2018.
Article in Chinese | WPRIM | ID: wpr-776387

ABSTRACT

The study was aimed to determine the efficacy of two pesticides in the control of aphids in Lonicera japonica, and study the applicability of pesticides in L. japonica. The number of insects was counted before and 2, 3, 7 and 10 days after the application of pesticide in the test area within different dosage groups. The method was 5-point sampling method. Five aphids on the L. japonica branches were selected, then the number of insects was recorded. The effect of the two pesticides on the control rate of aphid was more than 80% at 1 d after application. The results showed that the two pesticides had good efficacy. After 7 days and 10 days, the control effect was 100%. After 1 day of spraying, the effect of the two pesticides on the control of L. japonica aphids was more than 80%, which was higher than that of the control agent. The results showed that the two pesticides had good and fast effect. After 7 days and 10 days of spraying, the control effect was 100%. The control effect of two kinds pesticides for aphid sprayed in recommended dose on the L. japonica is good and showed no hytotoxicity.


Subject(s)
Animals , Aphids , Lonicera , Niacinamide , Pesticides , Pyridines , Sulfur Compounds
6.
Chinese Journal of Comparative Medicine ; (6): 84-90, 2018.
Article in Chinese | WPRIM | ID: wpr-703302

ABSTRACT

Objective To establish a micro volume blood sampling method via the saphenous vein for pharmacokinetic studies(PK studies)in mice, aiming at reducing animal use and alleviate animal pain in in vivo procedures. Methods CD-1 mice were intravenously or orally administered with model compounds A,B,C and D.Blood samples were collected by both the micro-sampling method and regular method at the same time points,and used for the measurement of plasma drug concentration. Pharmacokinetic parameters obtained from each method were compared. Results For each of the four compounds,plasma PK profiles generated by micro-sampling via saphenous vein were in good accordance with those by the regular sampling method via retro-orbital venous plexus. Conclusions Our newly developed micro-sampling blood collecting method can replace the regular blood collecting method used in pharmacokinetic studies in mice. It can significantly improve animal welfare by alleviating animal pain. The volume of blood withdrawn can be reduced by 80%,and the number of mice used for the pharmacokinetic studies can be reduced by 65%.

7.
China Occupational Medicine ; (6): 51-54, 2018.
Article in Chinese | WPRIM | ID: wpr-881662

ABSTRACT

OBJECTIVE: To compare the effects of different anesthetics and blood sampling methods on blood routine test results in experimental animals. METHODS: A total of 42 specific pathogen free( SPF) male Sprague Dawley( SD) rats and 59 SPF male Kunming( KM) mice were randomly divided into 4 groups( control group,ether group,chloral hydrate group and pentobarbital sodium group). Ether group animals were treated with ether inhalation anesthesia; animals in chloral hydrate group and pentobarbital sodium group were injected intraperitoneally with chloral hydrate or pentobarbital sodium. The control group received no anesthesia treatment. Blood samples were collected by different ways: orbital venous plexus,abdominal aorta or eyeball enucleation. White blood cell( WBC) count,red blood cell( RBC) count,platelet(PLT) count,hemoglobin(Hb) level and hematocrit(HCT) in blood samples were analyzed. RESULTS: The RBC count,Hb level and HCT of SD rats in pentobarbital sodium group were significantly lower than those in control group( P <0. 05). The HCT of SD rats in ether group was lower than that in control group( P < 0. 05). The WBC count of orbital venous plexus of KM mice was lower than that taken by eyeball enucleation in control group( P < 0. 05),but the WBC count of orbital venous plexus was higher than that taken by eyeball enucleation in chloral hydrate group( P < 0. 05). The RBC count,Hb level,HCT of KM mice in pentobarbital sodium group were significantly lower than those in control group(P < 0. 05). CONCLUSION: The anesthetic can affect the blood routine test results of experimental animals. Different blood sampling methods have effects on blood routine test results of KM mice.

8.
Pesqui. vet. bras ; 37(1): 31-35, jan. 2017. ilus., tab.
Article in English | LILACS, VETINDEX | ID: biblio-837447

ABSTRACT

We developed and evaluated a fast and simple method to obtain suitable bone samples for densitometry and chemical analysis through biopsies of the 12th rib of cattle. The postoperative recovery, dry matter intake (DMI) and average daily weight gain (ADG) was evaluated in 36 Nellore steers, nine of which were randomly selected for the control group and 27 others were rib biopsied. Every 30 days, rib biopsy was performed in nine steers, using a corded-electric pistol-grip drill coupled with a hole saw of a 3mm diameter pilot drill bit. This rib biopsy technique provided a suitable sample obtained in a fast way and allowed the surgeon to work alone with the animal slightly sedated and restrained in the crush. Dry matter intake (DMI) was not affected in biopsied animals. At the end of the experimental period (116 days) the average daily weight gain (ADG) was similar in the steers biopsied or not. The described method provided rib samples from cattle suitable for densitometry and chemical analysis of bone tissue without effects on health and performance. This information could greatly increase the accuracy for the diagnosis of phosphorus deficiency in cattle raised on pasture and allow the evaluation of bone metabolism in experimental animals.(AU)


No presente estudo foi desenvolvida uma técnica para se obter, de forma rápida e simples, amostras da 12a costela bovina por meio de biópsias. Avaliou-se a recuperação pós-operatória (durante 15 dias), o consumo de matéria seca (CMS) e o ganho de peso diário (GMD) de 36 novilhos Nelores, sendo nove animais controles e 27 submetidos à biópsia. A cada 30 dias biópsias de costelas foram realizadas em nove animais, usando uma furadeira elétrica acoplada a uma serra-copo com uma broca-guia de 3mm de diâmetro. Esta técnica de biópsia permitiu obter amostras ósseas de forma rápida, com o cirurgião operando sozinho e com os animais levemente sedados e em estação. Ao término do experimento (116 dias) o CMS e o GMD não foram afetados pelo procedimento cirúrgico. As amostras obtidas foram adequadas para exames radiográficos e subsequentes análises químicas. O conjunto de informações adquiridas com a técnica de biópsia de costelas permite aumentar a exatidão no diagnóstico da deficiência de fósforo em bovinos criados em pastagens e também realizar estudos sobre metabolismo ósseo em animais experimentais.(AU)


Subject(s)
Animals , Cattle , Chemical Phenomena/methods , Densitometry/methods , Densitometry/veterinary , Phosphorus/deficiency , Ribs , Biopsy/veterinary
9.
Chinese Traditional and Herbal Drugs ; (24): 3317-3321, 2017.
Article in Chinese | WPRIM | ID: wpr-852584

ABSTRACT

Objective: To determine the content of chlorogenic acid in Lonicerae Japonicae Flos by the combined near-infrared and variable selection methods. Methods: Synergy interval partial least squares (SIPLS), competitive adaptive reweighted sampling method (CARS), variable importance in projection (VIP), and successive projections algorithm (SPA) were used to build a chlorogenic acid quantitative model in Lonicerae Japonicae Flos and compare. High performance liquid chromatography (HPLC) was used as a reference to select the optimum variable screening method. Results: Study results showed that SIPLS was the most desirable method for chlorogenic acid in regression performance with Rpre2 at 0.990 3 and RMSEP at 2.316%. Conclusion: The quantitative model of chlorogenic acid established by NIR combined with SIPLS has good performance and meets the requirement of real-time analysis of traditional Chinese medicine production process.

10.
Organ Transplantation ; (6): 460-464, 2017.
Article in Chinese | WPRIM | ID: wpr-731709

ABSTRACT

Objective To investigate the status quo of knowledge-attitude-behavior about organ donation willingness and death attitudes of medical students majoring in nursing (nursing students). Methods A total of 409 nursing students from 3 medical colleges in Tianjin were recruited as study subjects by convenient sampling method. A crosssectional survey was carried out using organ donation scale and Chinese version of death attitude scale. Questionnaire input was performed by Epidata 3.1 software. The general situation of 409 nursing students was sumed up. The status quo of the knowledge-attitude-behavior about organ donation among nursing students and the correlation between the attitude towards death and the willingness to donate organs was analyzed. Results The nursing students lacked of comprehensive understanding of organ donation knowledge. A majority of nursing students held neutral or slightly positive attitudes towards organ donation. Only 10.5% of nursing students were willing to donate organs. Nursing students were inclined to death natural acceptance. Organ donation willingness was correlated with death attitudes. The fear of death was the primary factor affecting the organ donation willingness of nursing students (P<0.05). Conclusions At present, a small proportion of nursing students are willing to donate organs and they are affected by the fear of death. Social and medical colleges should strengthen the death education for nursing students to establish positive death attitudes and promote the development of organ donation.

11.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 456-461, 2016.
Article in Chinese | WPRIM | ID: wpr-670256

ABSTRACT

Objective To study the relationship between mental effort and personal time perspective during the process of individual changing bad habits.Methods 230 graduate students were collected to attend this longitudinal study of 21 days by experience sampling method.The data on mental effort and performance were obtained from the process of daily change of the bad behavior.Zimbardo Time Perspective Inventory (ZTPI) was applied to graduate students.The survey results were analyzed by hierarchical linear modeling (HLM).Results In 21 days,the mental effort of subjects showed very clear downward trend,the trend of the change was statistical significant (total score(5.63±2.62),t=-5.590,P<0.01).Mental effort didn't have significant difference in five kinds of behavioral objectives (keeping early hours,exercising daily,dieting,reading daily,limiting screen time) (P>0.05).The male obviously put more effort than the female during the study(t=2.743,P<0.01).Both Present Hedonism and Futurism were inversely related to mental effort,which was statistical significant (t=-2.504,P<0.05;t=2.39,P<0.05).Both Present Fatalism and Futurism had the effects on the changing trend of the mental effort regulatory,which was statistical significant (t=-3.099,P<0.01;t=-2.400,P<0.05).Conclusion The mental effort of changing the behavior will gradually decline during the process of habit establishment.The mental effort of subjects who had present fatalism or futurism show a faster decline.

12.
Chinese Journal of Schistosomiasis Control ; (6): 507-512, 2016.
Article in Chinese | WPRIM | ID: wpr-502802

ABSTRACT

Objective To optimize and simplify the survey method of Oncomelania hupensis snail in marshland endemic re?gion of schistosomiasis and increase the precision,efficiency and economy of the snail survey. Methods A quadrate experimen?tal field was selected as the subject of 50 m×50 m size in Chayegang marshland near Henghu farm in the Poyang Lake region and a whole?covered method was adopted to survey the snails. The simple random sampling,systematic sampling and stratified ran?dom sampling methods were applied to calculate the minimum sample size,relative sampling error and absolute sampling error. Results The minimum sample sizes of the simple random sampling,systematic sampling and stratified random sampling meth?ods were 300,300 and 225,respectively. The relative sampling errors of three methods were all less than 15%. The absolute sampling errors were 0.221 7,0.302 4 and 0.047 8,respectively. Conclusion The spatial stratified sampling with altitude as the stratum variable is an efficient approach of lower cost and higher precision for the snail survey.

13.
Journal of the Korean Ophthalmological Society ; : 1677-1683, 2015.
Article in Korean | WPRIM | ID: wpr-213421

ABSTRACT

PURPOSE: Although various sampling methods of tears from conjunctival sac have been reported, no previous study compared their effectiveness or efficiency based on protein extraction. By comparing the compliance, volume and protein concentration of each tear sampling method, we searched for the most efficient tear collection method. METHODS: Resting tear samples of 14 eyes of normal subjects were collected using Schirmer paper, capillary tube, cellolose acetate rod and 3 different ophthalmic sponges made of different materials and density (Merocel(R), KeraCel(R) and Weck-Cel(R)). After centrifugation of the collected tear samples, the tear volume and protein concentration were measured for each method. Additionally, the compliance of each tear sampling method was analyzed by numerically representing the amount of discomfort experienced during resting tear collection. RESULTS: The average volume retrieved by each tear sampling method was 9.0 +/- 1.1 microL with no significant differences between groups. The average concentration of protein retrieved by each tear sampling method was 5.3 +/- 1.2 microg/microL. Merocel(R) retrieved 7.6 +/- 0.61 microg/microL, which was significantly higher than other sampling methods (p < 0.05). The compliance of Merocel(R) and the capillary tube were the highest, while KeraCel(R) showed the lowest compliance. CONCLUSIONS: Merocel(R) retrieved the highest amount of protein and showed high compliance and may be the most effective and easily applicable tear sampling method in clinical settings.


Subject(s)
Capillaries , Centrifugation , Compliance , Methods , Porifera , Tears
14.
Braz. j. biol ; 72(4): 853-857, Nov. 2012. ilus
Article in English | LILACS | ID: lil-660381

ABSTRACT

Experimental studies in rivers and streams are extremely difficult to run due to the fact that the conditions of these environments are very complex and provide a high level of heterogeneity, which hinders the precise control and standardization of variables. In this study, we present a practical sampler that was designed to make it easier to conduct research projects involving benthic communities of lotic environments, as well as a new nondestructive technique for quantification of the macroalgal communities typically found in these habitats. The sampler consists of an acrylic square tube in which water flows normally inside. This structure carries a removable glass plaque with a known area and can simulate various ecological situations by changing both biotic and abiotic conditions. Thus, it can mitigate the differences between environmental characteristics where each sampler is exposed. The new technique involves capturing digital images that can monitor a unique macroalgal community in development throughout time and a more precise quantification when compared with other techniques that are widely applied. The sampler is easy to build and the images simple to quantify, allowing the detection of spatial and temporal variations in richness and abundance of investigated communities.


Os estudos experimentais em rios e riachos são extremamente difíceis de serem executados, visto que as condições desses ambientes são muito complexas e proporcionam um alto nível de heterogeneidade, o que dificulta o controle e a padronização precisa das variáveis. Nesse contexto, um prático amostrador foi desenvolvido para facilitar a execução de projetos de pesquisas envolvendo comunidades bentônicas de ambientes lóticos, além de constituir uma nova técnica não destrutiva para quantificação das macroalgas tipicamente encontradas nesses habitats. O amostrador consiste de um tubo de acrílico de seção quadrada, pelo qual a água corrente flui normalmente em seu interior. Tal estrutura porta uma placa de vidro removível com área conhecida e permite simular diversas situações ecológicas, variando tanto as condições abióticas como as bióticas, além de amenizar as diferenças entre as características ambientais a que está submetido cada um dos amostradores. Diversamente, a nova técnica consiste na captura de imagens digitais que permitem o acompanhamento temporal de uma mesma comunidade de macroalgas em desenvolvimento e uma quantificação mais precisa quando comparada com técnicas amplamente aplicadas na área. O amostrador é fácil de construir e as imagens são simples para quantificar, permitindo a detecção de variações espaço-temporais na riqueza e abundância das comunidades investigadas.


Subject(s)
Ecosystem , Environmental Monitoring/instrumentation , Seaweed , Biomass , Environmental Monitoring/methods , Rivers , Seaweed/isolation & purification
15.
Article in English | IMSEAR | ID: sea-152053

ABSTRACT

Background: Acute respiratory tract infection is a major cause of morbidity and mortality in developing and also developed countries. About 13 Million under 5 children dies every year in the world, 95% of them in developing countries, one third of total deaths are due to acute respiratory tract infection (ARI) 1. Objective: To assess the knowledge of mothers regarding acute respiratory tract infection (ARI) in urban and rural communities of Ahmadabad district. Materials and Methods: A cross sectional study was covering 500 mothers living in urban (five zone) and rural (five primary health centre (PHC) of sanand taluka) area of Ahmedabad district from September 2008 to March 2009. Results: Questionnaire regarding knowledge revealed that 35.2% of mothers preferred private set up as a place of choice for treatment (more in urban area 58.4%). 71.4% of mothers preferred allopathy as a choice of type of treatment. 40.8% of mothers rated diseases as serious (more in urban area 54.4%). 50.8% mothers were illiterate (70% in rural area) and 70.4% mothers were housewives. Conclusion: The study strongly towards the low utilization of basic health services in government set up, lack of mother’s education especially in prevention and control of ARI.Health education can change health care seeking behaviors and attitude of parents and other family members to take care of the ARI child during illness.

16.
Rev. bras. entomol ; 55(2): 253-266, June 2011. graf, mapas, tab
Article in English | LILACS | ID: lil-593253

ABSTRACT

Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil. To evaluate the reliability of data obtained by Winkler extraction in Atlantic forest sites in southern Brazil, we studied litter beetle assemblages in secondary forests (5 to 55 years after abandonment) and old-growth forests at two seasonally different points in time. For all regeneration stages, species density and abundance were lower in April compared to August; but, assemblage composition of the corresponding forest stages was similar in both months. We suggest that sampling of small litter inhabiting beetles at different points in time using the Winkler technique reveals identical ecological patterns, which are more likely to be influenced by sample incompleteness than by differences in their assemblage composition. A strong relationship between litter quantity and beetle occurrences indicates the importance of this variable for the temporal species density pattern. Additionally, the sampled beetle material was compared with beetle data obtained with pitfall traps in one old-growth forest. Over 60 percent of the focal species captured with pitfall traps were also sampled by Winkler extraction in different forest stages. Few beetles with a body size too large to be sampled by Winkler extraction were only sampled with pitfall traps. This indicates that the local litter beetle fauna is dominated by small species. Hence, being aware of the exclusion of large beetles and beetle species occurring during the wet season, the Winkler method reveals a reliable picture of the local leaf litter beetle community.


Avaliação dos besouros da liteira amostrados por extração Winkler na Floresta Atlântica do Sul do Brasil. Para avaliar a confiabilidade dos dados obtidos pela extração Winkler em coletas na Floresta Atlântica do Sul do Brasil, nós estudamos as assembléias de besouros da liteira em florestas secundárias (5 a 55 anos após abandono) e no estágio avançado em dois pontos no tempo sazonalmente diferentes. Para todos os estágios de renegeração, a densidade e abundância das espécies foram menores em abril comparado a agosto; porém, a composição das assembléias dos estágios florestais correspondentes foi similar em ambos os meses. Nós sugerimos que amostragens de pequenos besouros habitantes de liteira em diferentes pontos no tempo usando o método Winkler revelam padrões ecológicos idênticos. Um forte relacionamento entre a quantidade da liteira e a ocorrência de besouros indica a importância dessa variável no padrão temporal de densidade das espécies. Adicionalmente, o material amostrado foi comparado com dados de besouros obtidos utilizando armadilhas do tipo pitfall em um estágio avançado de regeneração. Cerca de 60 por cento das espécies de interesse capturadas em pitfall foram também amostradas pela extração Winkler. Poucos besouros com tamanho corporal grande para ser amostrado pela extração Winkler foram capturados com a armadilha pitfall. Isso indica que a fauna local de besouros da liteira é dominada por espécies pequenas. Portanto, sabendo da exclusão das espécies grandes e das espécies que ocorrem durante a estação chuvosa, o método Winkler revela um cenário confiável da comunidade local de besouros da literia.

17.
Neotrop. entomol ; 39(6): 912-917, nov.-dic. 2010. ilus, tab
Article in English | LILACS | ID: lil-572470

ABSTRACT

Pitfall trapping is probably the most frequently used method for sampling grounddwelling arthropods. While the capture of specimens in pitfall traps largely depends on the number of individuals in the sampled area, trap design and trapping effort for a given environment, can also affect sampling success. The aim of this study was to determine the best pitfall trapping design for collecting ground-dwelling arthropods in the wind-blown and cold arid steppe areas of Patagonia. We tested four designs of traps, six types of preservative and different times of activation as well as the quantity of traps. Both preservation attributes and sampling efficiency differed between different trap designs and fluids compared. We conclude that in order to obtain reliable data on the structure of a community of ground-dwelling arthropods in Patagonia, at least three pitfall traps per experimental unit are required. In addition, traps should be opened for a minimum of 10 days filled with 300 ml of 30 percent ethylene glycol. We also suggested the use of a simple trap design (i. e. without funnel or roof). We believe these findings will contribute to more appropriate sampling of the ground dwelling fauna of Patagonia as well as other arid areas, leading to more reliable diversity studies.


Subject(s)
Animals , Arthropods , Argentina , Entomology/methods , Soil
18.
Rev. para. med ; 24(2): 57-64, abr.-jun. 2010. ilus
Article in Portuguese | LILACS | ID: lil-593646

ABSTRACT

Objetivo: mostrar as diretrizes para a escolha do método de amostragem e para o cálculo do tamanho amostral,utilizados em projetos de pesquisa científica nas áreas das Ciências Biológicas e da Saúde. Método: realizado umcriterioso levantamento bibliográfico na literatura científica, a partir da compilação de trabalhos publicados em revistascientíficas e livros especializados e em bases de dados da rede BIREME. Conclusão: o entendimento dos diferentestipos de amostragem, assim como o cálculo correto para o tamanho da amostra, são pontos fundamentais para o sucessona realização de uma pesquisa científica.


Objective: to show the methodological aspects and guidelines for the choice of sampling method and sample sizecalculation used in scientific research projects of Life Sciences and Health areas. Method: for the organizationof this present review study, a detailed bibliographic research of the scientific literature has been made, from thecompilation of papers published in scientific magazines and specialized books, as well as from databases of Bireme?s64 Revista Paraense de Medicina V.24 (2) abril-junho 2010server. Conclusion: Understanding about the different types of sampling methods, as well as the correct sample sizecalculation, are important steps to success in conducting a scientific research.


Subject(s)
Research Design/statistics & numerical data , Biostatistics , Sampling Studies , Methodology as a Subject
19.
Neotrop. entomol ; 36(5): 685-692, Sept.-Oct. 2007. ilus, tab, graf
Article in English | LILACS | ID: lil-468100

ABSTRACT

Sudies of species survey are important to know the available natural resources and to get useful information about the ecological characteristics of a specific area. There are not studies, on this issue, related to social wasps, in the Triângulo Mineiro region. The present study describes the diversity of species found in fragments of the cerrado region in Uberlândia, MG, and their temporal distribution. The field study was conducted from October 2003 to September 2004, and 43 samplings were carried out using active searching (24) and point sampling (19) methodologies. Twenty-nine species were found in 10 genera, Polybia and Polistes corresponding to 51.5 percent of the total listing. Mischocyttarus cerberus styx Richards represented 26.5 percent of the total individuals recorded by active searching and Agelaia pallipes (Olivier) corresponded to 57.6 percent by point sampling. Two species had their first record for the state of Minas Gerais: Polybia striata (Fabricius) and M. cerberus styx. The studied fragments presented a high level of diversity (H’ = 0.66 to 1.16), a large number of rare species and a few common species. To collect the more common species the point sampling method was satisfactory while active searching was better to collect the rarer species. The active searching methodology was more efficient than point sampling, however some species could only be collected by point sampling. These factors showed that in order to carry out a wasp survey, a combination of different collection methodologies seems to be more appropriate.


Estudos de levantamento de espécies são importantes para o conhecimento dos recursos naturais além de contribuírem com informações de características ecológicas de uma determinada região. Não há estudos dessa natureza abordando vespas sociais no Triângulo Mineiro. O presente estudo investiga a diversidade das espécies encontradas em fragmentos de cerrado em Uberlândia, MG, e sua distribuição temporal. O trabalho de campo foi conduzido de outubro de 2003 a setembro de 2004, realizando-se 43 amostragens utilizando as metodologias de busca ativa e amostragem pontual. Foram encontradas 29 espécies em 10 gêneros, destacando-se Polybia e Polistes com 51,7 por cento dos espécimes coletados. Mischocyttarus cerberus styx Richards representou 26,5 por cento do total de indivíduos registrados para busca ativa e Agelaia pallipes (Olivier) correspondeu a 57,6 por cento para amostragem pontual. Duas espécies apresentaram primeiro registro para Minas Gerais: Polybia striata (Fabricius) e M. cerberus styx. Os fragmentos estudados apresentaram elevado índice de diversidade (H’ = 0,66 a 1,16), grande quantidade de espécies raras e poucas espécies comuns. O método de amostragem pontual foi satisfatório para coletar as espécies mais comuns enquanto a busca ativa foi importante para a coleta de espécies raras. A metodologia de busca ativa foi mais eficiente, em termos de abundância, que a amostragem pontual, embora algumas espécies só tenham sido coletadas pelo método de amostragem pontual. Esses fatores revelaram que para efetuar um levantamento de vespas uma combinação de diferentes metodologias de coleta parece ser o mais indicado.


Subject(s)
Animals , Wasps/classification , Brazil , Demography
20.
Space Medicine & Medical Engineering ; (6)2006.
Article in Chinese | WPRIM | ID: wpr-579732

ABSTRACT

Objective To study the application of the linear sampling method(LSM) in 2D electromagnetic inverse scattering imaging and to mainly discuss the imaging quality of LSM with partial-view data.Methods Get the norm of solution vector to the equivalent integral equation using numerical calculation in every sampling point at imaging region,and represent the norm with gray to reconstruct the scattering shape.Results Under all incident angles [0,360?] and all observation angles [0,360?],the imaging quality of the far-field pattern of scattering wave was obtained very well.But when reducing the range of the incident angles and observation angles,the imaging quality declined.Particularly,the imaging quality in the case of both incident angles and observation angles being at the same side of the observed object,were much better than both in opposite sides.Furthermore,the profile of the object was imaged more clearly as its position corresponding to the orientation of the incident/observation angle.Conclusion Although the imaging quality will decline with partial-view data in electromagnetic inverse scattering,the effectiveness of imaging with LSM still deserves attention.

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