Determinación de viabilidad, vigor y banco de semillas de retamo espinoso (Ulex europaeus L.) en un Andisol de un ecosistema de Páramo

El retamo espinoso (Ulex europaeus L.) es una planta introducida invasora de rápido crecimiento y diseminación, con producción de semillas, que permanecen latentes en los primeros 5 cm de profundidad del suelo; esta planta altera espacios ecológicos nativos, áreas de producción agropecuaria y su control y erradicación no es exitosa. Conocer ciertas características de las semillas del retamo facilitará su control. Así, el objetivo de este trabajo, fue determinar el vigor, la viabilidad y el banco de semillas de retamo espinoso, en zonas del páramo de Sumapaz. Para las pruebas, se colectaron semillas en tres sitios: Delicias, Usabá y Laguna. La prueba de vigor, se llevó a cabo mediante conductividad eléctrica y la de viabilidad, por ensayo topográfico de tetrazolio; en cada prueba, se realizó cuatro repeticiones, cada una con 100 semillas; el diseño estadístico fue completamente al azar. Para el banco de semillas, se tomaron muestras de suelo, a profundidades 0-5, 5-10 y 10-20 cm y se dispusieron en bandejas de aluminio. La prueba de vigor mostró que, después de 6 horas de hidratación, la cantidad de iones lixiviados se estabilizó, con un valor de 38,51 µs.cm -1 g-1, a las diez horas, afirmando alto vigor de semillas. La prueba de viabilidad presentó un 98 % y el banco de semillas registró mayor cantidad en el horizonte de 10-20 cm, con 950 semillas.m2, en la Laguna. Este estudio demuestra que las semillas de retamo tienen altos valores de vigor, viabilidad y un abundante banco de semillas distribuidas a diferentes profundidades.

The gorse (Ulex europaeus L.) is an invasive introduced plant of rapid growth and spread, with seeds production that remain dormant in the first 5 cm of soil depth, this plant alters native ecological spaces, areas of agricultural production, and its control and eradication is not successful. Know certain characteristics of gorse seeds will facilitate its control. Thus, the purpose of this work was to determine the vigor, viability and seed bank of gorse in areas of the Sumapaz paramo. For the tests, seeds were collected in three sites: Delicias, Usabá and Laguna. The vigor test was carried out by means of electrical conductivity and the viability test by tetrazolium topographic assay, in each test four repetitions were carried out, each with 100 seeds, the statistical design was completely random. For the seed bank, soil samples were taken at depths of 0-5, 5-10 and 10-20 cm, and placed in aluminium trays. The vigor test showed that after 6 hours of hydration, the amount of leached ions stabilized with a value of 38.51 µs.cm -1 g-1 at ten hours, confirming high seed vigor. The viability test presented 98 % and the seed bank registered a greater quantity in the 10-20 cm horizon with 950 seeds.m2 in the Laguna. This study shows that gorse seeds have high values of vigor, viability, and an abundant seed bank distributed at different depths.

Productive characteristics of sunflower genotypes irrigated with different levels of saline water

Sunflower is suitable for family farmers from Northeast Brazil who are benefited by the production of grain and oil and is adequate for crop rotation and for honey production. The need for irrigation in this region leads to the realization of this study for evaluating the production components of four sunflower genotypes irrigated with different levels of water salinity. The study was carried out in the municipality of Remigio, Paraíba, Brazil, using a randomized block with split plots experimental design in a 5 x 4 factorial arrangement. Treatments consisted of five electrical conductivity levels of the irrigation water at 25 °C (L1 - 0.14 (reservoir water), L2 - 1.50, L3 - 2.50, L4 - 3.50, and L5 - 4.50 dS m- 1), and four sunflower genotypes (C1 - Embrapa 122-V2000, C2 - Olisun 03, C3 - AG 963, and C4 - Multissol) with three replicates. The irrigation water salinity levels tested did not influence the variables studied. Different values of the variables among sunflower genotypes were due to characteristics inherent to each genotype. Sunflower genotype Olisun 03 presented the highest oil content, while the lowest content was observed in Multissol.

Research Progress on the Determination of Electrical Conductivity in Forensic Science / 法医学杂志

Electrical conductivity （EC） is an important physical and chemical index in electrochemical analysis. In recent years, with the penetration and reference of transformation medicine and interdisciplinary theory and technology in the forensic field, new applications of EC in the field of forensic science have been developed. This paper reviews three aspects of the application of EC, the determination of biological tissue freshness, postmortem interval estimation and the application in forensic taphonomy, in order to provide reference for relevant scientific research and related practices.

Vigor tests in seeds creole of Phaseolus lunatus L / Testes de vigor em sementes crioulas de Phaseolus lunatus L

Seeds with a good physiological quality are essential to high productivity. However, for some seeds, Phaseolus lunatus L., the viability and vigor analyze show deficiency in quality. This work aimed to evaluate the physiological quality of Phaseolus lunatus L. seeds using several vigor tests. The study was realized at the Laboratory of Seed Analysis of the Agricultural Sciences Center of the Federal University of Paraíba, in Areia ­ PB, Brazil. We used seeds from five cultivars of P. lunatus (Branca, Orelha de Vó, Cearense, Rosinha, and Roxinha). To determine the physiological quality, we measured the water content, the viability and vigor test (germination, emergence, electrical conductivity, tetrazolium, first germination count and emergence, seedling length and dry mass). We used a completely randomized design for seeds evaluation, and the field test was performed in randomized blocks. The water content of P. lunatus did not differ among the cultivars, indicating a uniformity in the percentage of moisture. Also, the percentage and speed of emergency and the dry mass of seedlings did not differ among the varieties. The tetrazolium and electrical conductivity tests indicated that Rosinha cultivar had the worst viability concerning the other cultivars, showing a low percentage of living tissue and lower electrical conductivity. The seeds of Roxinha cultivar had the better physiological quality, and the Cearense cultivar had the worst quality evaluation. We recommend the tetrazolium test but not the electrical conductivity test to evaluate the vigor of P. lunatus.

Em qualquer cultura, para se ter uma elevada produtividade é indispensável à aquisição de sementes com alta qualidade fisiológica, mas para sementes de Phaseolus lunatus L., ainda ocorre deficiência em análises de viabilidade e vigor. Dessa forma, o objetivo neste trabalho foi avaliar a qualidade fisiológica das sementes de cultivares de Phaseolus lunatus por diferentes testes de vigor. A pesquisa foi realizada no Laboratório de Análise de Sementes do Centro de Ciências Agrárias da Universidade Federal da Paraíba, em Areia - PB, com sementes de cinco cultivares de Phaseolus lunatus (Branca, Orelha de Vó, Cearense, Rosinha e Roxinha). Para avaliação da qualidade fisiológica das sementes determinou-se o teor de água e realizou-se testes de viabilidade e vigor (germinação, emergência, condutividade elétrica, tetrazólio, primeira contagem de germinação e emergência, comprimento e massa seca de plântulas). O delineamento utilizado foi o inteiramente casualizado, com exceção dos testes realizados em campo, que foi em blocos ao acaso. O teor de água das sementes dos cultivares de feijão-fava não diferiu estatisticamente entre si, indicando que houve uniformidade na porcentagem de umidade. Não houve diferença significativa entre as sementes dos cultivares de feijão-fava quando avaliou-se a porcentagem e velocidade de emergência, bem como a massa seca de plântulas. Os resultados dos testes de tetrazólio e condutividade elétrica constatou-se maior viabilidade para as sementes do cultivar Roxinha, Branca, Cearense e Orelha de Vó quando comparadas com as da Rosinha, uma vez que houve um maior percentual de tecidos vivos e uma menor condutividade elétrica, respectivamente. As sementes do cultivar Roxinha são de melhor qualidade fisiológica e, o cultivar Cearense de pior qualidade; o teste de tetrazólio é recomendado para avaliação do vigor de sementes de cultivares de Phaseolus lunatus, enquanto, o teste de condutividade elétrica não é recomendado para avaliar o vigor das sementes dos cultivares de P. lunatus.

Bacterias halófilas con potencial para la recuperación de suelos salinizados en Sáchica-Boyacá, Colombia

Es posible usar bacterias halófilas aisladas de ambientes salinos como una posible alternativa de rehabilitación de suelos salinizados para la producción agrícola y agropecuaria. En este estudio se evaluaron seis bacterias halófilas para determinar su potencial en la disminución de la conductividad eléctrica (Ce) de suelo moderadamente salino del municipio de Sáchica- Boyacá (Colombia). Las bacterias se aislaron en agar nutritivo con diferentes concentraciones de NaCl, luego fueron inoculadas en el suelo (3 kg puesto en materas) para realizar un bioensayo en invernadero durante 2 meses. Se realizaron dos fases, la primera hasta conseguir un valor de 2 ds/m (Ce) con el fin de sembrar plantas de tomate en la segunda fase. Se realizaron mediciones semanales de la (Ce) durante todo el bioensayo y solo en la fase 2 se determinaron semanalmente variables cualitativas de crecimiento de tomate (altura, número de hojas, área foliar, marchitez y clorosis). Los resultados mostraron un efecto directo de las bacterias halófilas en la disminución de la (Ce) del suelo, pasando de 5.2 a 0.8 ds/m (T1), 0.7 ds/m (T2), 0.8 ds/m (T3), 0.6 ds/m (T4), 0.7 ds/m (T5), 0.7 ds/m (T6), 3.0 ds/m (testigo), valores que corresponden a salinidad muy ligera (< 2 ds/m). En relación con las variables agronómicas, se evidenciaron mejoras en las características evaluadas en comparación con el testigo absoluto, sobre todo en altura y número de hojas de las plantas. Para el testigo absoluto se perdieron 80 % de las unidades experimentales, mientras que en el suelo con los diferentes tratamientos solo en algunos casos se perdió el 20 %. De acuerdo con esto, se evidencia que las bacterias halófilas utilizadas en esta investigación tienen potencial para la rehabilitación de suelos salinizados.

It is possible to use halophilic bacteria isolated from saline environments as a possible alternative for the rehabilitation of salinated soils for agricultural and agricultural production. Six halophilic bacteria were evaluated to determine their potential in the reduction of the electrical conductivity (Ce) of moderately saline soil in the municipality of Sáchica-Boyacá (Colombia). The bacteria were isolated on nutritive agar with different concentrations of NaCl, then inoculated in the soil (3 kg placed in pots) to perform a bioassay in the greenhouse for 2 months. Two phases were carried out, the first until obtaining a value of 2 ds / m (Ce) in order to plant tomato plants in the second phase. Weekly measurements of the ( Ce ) were made throughout the bioassay and only in phase 2 were determined weekly qualitative variables of tomato growth (height, number of leaves, foliar area, wilting and chlorosis). The results showed a direct effect of the halophilic bacteria in the decrease of the (Ce) of the soil, going from 5.2 to 0.8 ds / m (T1), 0.7 ds / m (T2), 0.8 ds / m (T3), 0.6 ds / m (T4), 0.7 ds / m (T5), 0.7 ds / m (T6), 3.0 ds / m (Control), values that correspond to very light salinity (< 2 ds / m). Regarding the agronomic variables, improvements were observed in the characteristics evaluated in comparison with the absolute control, especially in height and number of leaves of the plants. For the absolute control 80 % of the experimental units were lost, while in the soil with the different treatments only in some cases 20 % was lost. Accordingly, it is evident that the halophilic bacteria used in this research have potential for the rehabilitation of salinated soils.

Physiological changes in seeds and seedlings of pumpkins submitted to salt stress / Alterações fisiológicas em sementes e mudas de abóboras submetidas a estresse salino

Salinity is one of the most limiting environmental factors for plant growth in semi-arid regions.Excessofsalts reduces water potential, causes physiological drought and can influence germination and initial growth of plants. The objective of this work was to study physiological and metabolic changes in seeds and seedlings of pumpkin (Cucurbita pepo cultivars Caserta and Redonda and C. maxima cv. Coroa)in a saline condition of salt stress. Thus, we it was quantified germination parameters; seedlings growth; seeds and seedlings respiration; degradation of total soluble sugars, reducing sugars and total proteins in cotyledons and the activity ascorbate peroxidase (APX), glutathione-S-transferase (GST) and catalase (CAT) during germination and initial growth of the pumpkin species studied in saline conditions. The experimental design was totally randomized in a factorial scheme 6x3, with six electrical conductivities (0; 2; 4; 6; 8 e 10 dS.m-1) and three cultivars (Redonda, Caserta and Coroa). Salinity did not influence the rate of seed respiration during the germination, although seedlings respiration decreased, as well as its vigour. Total sugars were degraded, while there was accumulation of reducing sugars and proteins in cotyledons of germinating seeds in salt solutions. Increased electrical conductivity reduced APX activity in the embryo and CAT in cotyledons, but did not influence GST. Pumpkin seedlings showed low tolerance to salt stress.

A salinidade é um dos fatores limitantes para o crescimento das culturas nas regiões áridas e semiáridas. O excesso de sais provoca uma redução no potencial hídrico e causa seca fisiológica e influencia na germinação e crescimento inicial de plântulas Objetivou-se estudar possíveis alterações fisiológicas e metabólicas em sementes e plântulas de abóboras (Cucurbita pepo cultivars Caserta and Redonda and C. maxima cv. Coroa), Sendo assim, avaliou-se em sementes e plântulas os parâmetros da germinação (porcentagem e velocidade); crescimento de plântulas; respiração de sementes e plântulas; degradação de açúcar solúveis totais, açúcar redutores e proteínas totais nos cotilédones e atividade das enzimas ascorbato peroxidase (APX), glutationa-S-transferase (GST) e catalase (CAT) durante a germinação e crescimento inicial das cultivares de abóbora em soluções salinas. O delineamento experimental foi inteiramente casualizado em esquema fatorial 6x3, com seis condutividades elétricas (0; 2; 4; 6; 8 e 10 dS.m-1) e três cultivares (Redonda, Caserta e Coroa). A salinidade não influenciou a taxa de respiração das sementes durante a germinação, no entanto, a respiração das plântulas diminuiu, assim como o vigor das plântulas. Houve degradação dos açúcares totais e acúmulo de açúcares redutores e proteínas em cotilédones de sementes submetidas a soluções salinas. O aumento da condutividade elétrica induziu redução da atividade de APX no embrião e de CAT nos cotilédones, mas não influenciou GST. Cultivares de aboboras apresentaram baixa tolerância ao estresse salino.

Foliar application of plant growth regulators changes the physiological quality of crambe seeds

The application of plant growth regulators can manipulate the development of cultivated plants, and their physiological effects may be reflected in the physiological quality of the seeds. This study evaluated the effects of plant growth regulators (PGR) on the physiological quality of crambe seeds produced in the 2014 and 2015 harvests. During crop development, we applied two foliar sprayings of the following treatments: 1) control treatment with distilled water; 2) indole-3-acetic acid 100 mg L-1 (IAA); 3) 3-gibberellic acid P.A. 100 mg L-1 (GA3); 4) commercial PGR Stimulate® 6 mL L-1. The seeds were harvested and evaluated for water content, germination percentage and germination speed index (GSI), electrical conductivity and concentrations of leached Ca, Mg and K ions. Means were compared by Tukey ́s and Dunnett tests (p<0.05). Applying Stimulate® increased the germination percentage and the germination speed index, while IAA application showed an opposite effect, increasing the electrical conductivity of crambe seeds. Calcium leaching decreased with IAA application, and all regulators reduced K leaching. We therefore infer that the application of plant growth regulators influences the physiological quality of crambe seeds.

Relationship between Electrical Conductivity and Chemical Content of Rat Skeletal Muscle Impregnating Solution and Postmortem Interval / 法医学杂志

Objective To study the mechanism of change of the electrical conductivity （EC） of rat skeletal muscle impregnating solution that occurs with the change of postmortem interval （PMI）. Methods Healthy Sprague-Dawley rats were killed and kept at about 25 ℃. Skeletal muscles were extracted at different PMI--immediate （0 d）, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, and 7 d, then mixed with deionized water to make impregnating solution with a mass concentration of 0.1 g/mL. The solution's EC and nine common chemicals in it, such as potassium ion, calcium ion, and chloride ion, were determined. Results EC increased gradually with the extending of PMI （P=0.024） during the 7 days after the rats' death. The content of uric acid （P=0.032）, urea nitrogen （P=0.013） and phosphorus （P=0.022） also increased during the extension. However, the content of magnesium ions decreased with extending of PMI （P=0.047）. The correlation between potassium ion, sodium ion, chlorine ion, calcium ion, creatinine and PMI were weak （P>0.05）. Conclusion The molecular basis of skeletal muscle EC change in rats after their death is the changes of uric acid, urea nitrogen, inorganic phosphorus and other chemical components. Furthermore, combine use of various indicators can improve the accuracy of the EC method to infer PMI.

Relationship between Electrical Conductivity and Related Biochemical Indicators of Rat Cerebrum Tissues and Postmortem Interval / 法医学杂志

Objective To explore the relationship between the electrical conductivity （EC） and biochemical indicators of rat cerebrum tissues and postmortem intervals （PMIs） and discuss the mechanism of applying EC to infer PMI. Methods Forty healthy Sprague-Dawley rats were sacrificed and stored in an environment of about 25 ℃. The whole cerebrum tissues of rats were removed respectively at different PMIs of 0, 1, 2, 3, 4, 5, 6, and 7 d, and then made into homogenized impregnation solution. The EC and related biochemical indicators （potassium, sodium, chloride, calcium, inorganic phosphorus, magnesium, uric acid, urea nitrogen and creatinine） in cerebrum tissue impregnation solution were determined, and the relationships among EC in impregnation solution, related biochemical indicators and PMI were analyzed. Results The EC in cerebrum tissues increased gradually with the extension of PMI, and the content of uric acid, urea nitrogen and inorganic phosphorus in its impregnation solution also increased gradually with the extension of PMI. The correlation of EC, uric acid, urea nitrogen, and inorganic phosphorus with PMI was relatively good （R2 was 0.95-0.99）, and there was a linear correlation between the content change of uric acid, urea nitrogen, inorganic phosphorus and EC （R2 was 0.97-0.99）. The changes of the other 6 kinds of biochemical indicators with the extension of PMI within 7 d after the rats' death were non-significant （P>0.05）. Conclusion The correlation between EC in cerebrum tissues, uric acid, urea nitrogen, inorganic phosphorus and PMI were relatively good, and combining various indicators can also improve the accuracy of PMI estimation.

Caracterização físico-química do colostro de búfalas na primeira ordenha pós-parto por meio de absorção infravermelha / Physico-chemical characterization of buffalo colostrum at the first postpartum milking by infrared absorption

Objetivou-se caracterizar o colostro da primeira ordenha de búfalas da raça Murrah utilizando a metodologia não oficial de absorção infravermelha. Para isso, foram colhidas amostras individuais de 42 fêmeas multíparas, por meio de ordenha manual. As amostras foram coletadas em até 12 h após o parto e encaminhadas para determinação de gordura, proteína, lactose, sólidos totais e sólidos não gordurosos por meio de absorção infravermelha. Realizamos também a contagem de células somáticas (CCS) e leitura de condutividade elétrica (CE) do colostro. Os dados foram submetidos à análise estatística descritiva através do procedimento proc means. Os valores de condutividade elétrica foram divididos em quatro classes e as médias das características físico-químicas das diferentes classes foram comparadas pelo teste T com 5% de significância. Também foi realizada análise de correlação entre as características químicas, CCS e CE do colostro. Foram obtidas médias de 4,34 ± 3,24% para gordura, 11,88 ± 3,93% para proteína, 2,54 ± 0,9% para lactose, 10,01 ± 3,33% para caseína, 26,56 ± 4,18% para sólidos totais, 16,20 ± 3,70% para sólidos não gordurosos, 316,86 ± 341,56 mil células somáticas, e 4,44 ± 0,81 mS cm-1 para condutividade elétrica do colostro. O colostro de búfalas ordenhadas em até 12h pós-parto apresenta elevado teor de proteína. Além disso, observamos que quanto maior a leitura da condutividade elétrica, menores são os percentuais de proteína, caseína e sólidos não gordurosos no colostro.

The objective of this study was to characterize the colostrum of the first milking of buffaloes of the Murrah breed using the infrared absorption. For this, individual samples of 42 multiparous females were collected by manual milking. Samples were collected up to 12h after delivery and sent for determination of fat, protein, lactose, total solids and non-greasy solids by the infrared absorption method. We also performed somatic cell counts (SCC) and electric conductivity (EC) reading of colostrum. The data were submitted to descriptive statistical analysis through the procedure proc means. The values of electrical conductivity were divided into four classes and the means of physical-chemical characteristics of the different classes were compared by the T test with 5% significance. A correlation analysis was also performed between the chemical characteristics, SCC and EC of colostrum. Averages of 4.34 ± 3.24% for fat, 11.88 ± 3.93% for protein, 10.01 ± 3.33% for casein, 2.54 ± 0.9% for lactose, 26, 56 ± 4.18% for total solids, 16.20 ± 3.70% for non-greasy solids, 316.86 ± 341.56 mil somatic cells and 4.44 ± 0.81 mS cm -1 for electrical conductivity of colostrum. The colostrum of milked buffaloes up to 12 hours postpartum presents high protein content. In addition, we observed that the higher the electrical conductivity reading, the lower the percentages of protein, casein and non-greasy solids in colostrum.

Relationship between Early Postmortem Interval and Electrical Conductivity of Rat Liver, Spleen and Kidney after Death in Rats / 法医学杂志

OBJECTIVES@#To determine the electrical conductivity （EC） of the liver, spleen and kidney of rats at different postmortem intervals （PMIs） within 24 hours for investigating the relationship between EC of different organs and early PMI.@*METHODS@#Totally 45 SD rats were sacrificed by cervical dislocation and kept at a constant temperature of 25 ℃. Tissues were taken from the liver, spleen, and kidney of rats at 0, 3, 6, 9, 12, 15, 18, 21 and 24 h. Impregnating solution with a mass concentration 0.1 g/mL was prepared using deionized water. The EC value of impregnating solution with different organs was separately determined. The regression equations of EC and PMI for different organs were established, respectively. The relationship between EC of different organs and early PMI was analysed in deceased rats.@*RESULTS@#The relationship between PMI and EC of the liver and spleen was well fitted with the linear equation. The liver showed the best fitting degree followed by the spleen, while the EC of the kidney showed no significant changes within 24 h. There was a good linear relationship between early PMI and the EC of the liver and spleen.@*CONCLUSIONS@#A good linear relationship between early PMI and the EC of the liver and spleen can be found in rats after death, which can be used for the early PMI estimation.

Método para medir densidad ósea a partir de conductividad eléctrica calculada por Tomografía de Impedancia Eléctrica / Method for measuring bone density through the electrical conductivity calculated by Electrical Impedance Tomography

RESUMEN: En este trabajo se presenta un método para medir densidad ósea. El método consiste en la medición de conductividad eléctrica de material óseo por medio de Tomografía de Impedancia Eléctrica (TIE). Se hace uso de una celda de prueba con valores simulados de hueso aplicando corrientes y registrando voltajes, para después usar una reconstrucción por retroproyección y generar mapas de conductividad por medio de gráficas. Los datos obtenidos son analizados y a partir de ellos se obtiene una distribución de la medida de conductividad eléctrica del material óseo, que varía dependiendo del grado de porosidad que presenta en cada región. La ventaja de utilizar el método de tomografía de impedancia es que permite medir la conductividad efectiva del hueso porque se mide en todas las direcciones. Por lo tanto es posible determinar porosidad en material óseo usando mediciones de conductividad eléctrica por medio del método TIE propuesto, lo cual permite calcular un valor numérico de densidad ósea.

ABSTRACT: In this paper a method to measure bone density was developed. The method consists in the measurement of electrical conductivity of bone by Electrical Impedance Tomography (EIT). A phantom with simulated data of bone is used, applying currents and recording voltages; then a backprojection reconstruction is used to generate maps with graphic conductivity values. The data obtained were analyzed and was obtained a distribution of electrical conduc tivity of bone, wich varies according to the bone porosity level in each region. A significant advantage of using this method is that is possible to measure electrical conductivity in several directions of the bone, obtaining an effective conductivity. Therefore it is possible to determine the porosity in the bone with measurements of electrical conductivity using the proposed EIT method, this allows to calculate a numerical value for bone density.

Study on the relationship between postmortem interval and electrical conductivity of different tissues / 中国法医学杂志

Objective To determine the electrical conductivity of cerebrum, liver, lung and muscle of rats at different postmortem intervals for investigating the relationship between EC and PMI. Methods Healthy Sprague-Dawley rats were sacrificed and kept at constant temperature of 25°C. Cerebrum, lung, liver and muscle were extracted at different PMIs of immediate (0d), 1d, 2d, 3d, 4d, 5d, 6d and 7d, and their extraction liquids were prepared with ultrapure water at the ratio of 1g:10mL. EC were separately determined for different tissues and organs. The relationships between EC of different tissues and organs and PMI were analyzed and their regression functions were established. The characteristics of EC values for four tissues and organs were compared and their decomposition processes were discussed. Results EC of brain and muscle showed no significant changes within 1d, and increased rapidly during 2~7d; but EC of liver and lung started to increase within 1d and increased rapidly during 2~7d.The relationship between EC of different tissues and organs and PMI were well fitted with cubic equations and liver gained the highest coefficient (R2=0.96). Additional, the EC of four organs presented various increasing laws in different periods of PMI. Conclusion The EC of cerebrum, lung, liver and muscle of rats were well fitted with PMI and the determination of EC of cadaver tissues can be expected to become an effective method for PMI estimation in forensic practice.

Relationship between Electrical Conductivity and Decomposition Rate of Rat Post-mortem Skeletal Muscle / 法医学杂志

Objective T o analyze the relationship am ong electrical conductivity (E C ), total volatile basic nitrogen (T V B-N ), w hich is an index of decom position rate for m eat production, and postm ortem inter-val (PM I). T o explore the feasibility of E C as an index of cadaveric skeletal m uscle decom position rate and lay the foundation for PM I estim ation. Methods H ealthy Sprague-D aw ley rats w ere sacrificed by cervical vertebrae dislocation and kept at 28℃. M uscle of rear lim bs w as rem oved at different PM I, ho-m ogenized in deionized w ater and then skeletal extraction liquid of m ass concentration 0.1 g/m L w as prepared. E C and T V B-N of extraction liquid w ere separately determ ined. T he correlation betw een E C (x1) and T V B-N (x2) w as analyzed, and their regression function w as established. T he relationship be-tw een PM I (y) and these tw o param eters w ere studied, and their regression functions w ere separately established. Results T he change trends of E C and T V B-N of skeletal extraction liquid at different PM I w ere alm ost the sam e, and there w as a linear positive correlation betw een them . T he regression equation w as x2=0.14 x1-164.91 (R2=0.982). E C and T V B-N of skeletal m uscle changed significantly w ith PM I, and the regression functions w ere y=19.38 x13-370.68 x12+2526.03 x1-717.06 (R2=0.994), and y=2.56 x23-48.39 x22+330.60 x2-255.04 (R2=0.997), respectively. Conclusion E C and T V B-N of rat postm ortem skeletal m uscle show sim ilar change trends, w hich can be used as an index for decom position rate of cadaveric skeletal m uscle and provide a m ethod for further study of late PM I estim ation.

Relationship between Electrical Conductivity and Decomposition Rate of Rat Postmortem Skeletal Muscle / 法医学杂志

OBJECTIVES@#To analyze the relationship among electrical conductivity （EC）, total volatile basic nitrogen （TVB-N）, which is an index of decomposition rate for meat production, and postmortem interval （PMI）. To explore the feasibility of EC as an index of cadaveric skeletal muscle decomposition rate and lay the foundation for PMI estimation.@*METHODS@#Healthy Sprague-Dawley rats were sacrificed by cervical vertebrae dislocation and kept at 28 ℃. Muscle of rear limbs was removed at different PMI, homogenized in deionized water and then skeletal extraction liquid of mass concentration 0.1 g/mL was prepared. EC and TVB-N of extraction liquid were separately determined. The correlation between EC (x₁) and TVB-N (x₂) was analyzed, and their regression function was established. The relationship between PMI (y) and these two parameters were studied, and their regression functions were separately established.@*RESULTS@#The change trends of EC and TVB-N of skeletal extraction liquid at different PMI were almost the same, and there was a linear positive correlation between them. The regression equation was x₂=0.14x₁-164.91(R²=0.982). EC and TVB-N of skeletal muscle changed significantly with PMI, and the regression functions were y=19.38x₁³-370.68x₁²+2 526.03 x₁-717.06(R²=0.994), and y=2.56x₂³-48.39x₂²+330.60x₂-255.04(R²=0.997), respectively.@*CONCLUSIONS@#EC and TVB-N of rat postmortem skeletal muscle show similar change trends, which can be used as an index for decomposition rate of cadaveric skeletal muscle and provide a method for further study of late PMI estimation.

Physical and physiological quality of the Lippia rotundifolia seeds according to the osmotic conditioning and electrical conductivity / Qualidade física e fisiológica das sementes de Lippia rotundifolia em função do condicionamento osmótico e condutividade elétrica

ABSTRACT: Lippia rotundifolia is a native species of the Cerrado, endemic to the chain backbone and highly aromatic, whose essential oil has medicinal properties of high pharmacological value, but because it is a non-domesticated species, little is known about its spread. Due to its importance, the objective was to evaluate the effect of the osmotic conditioning on the physical and physiological quality of seeds. The experimental design was completely randomized with four replications of 100 seeds, being treatments consisted of two kinds of seeds (with and without tegument) subjected to ten days of immersion in water (0, 2, 4, 6, 12, 24, 48, 72, 96 and 120 hours). After each period, the seeds were submitted to the electrical conductivity test and germination. Electrical conductivity and germination there is a directly proportional relationship, while the best osmotic conditioning time is achieved with the seed husk and immersed in water for 48 hours.

RESUMO: Lippia rotundifolia é uma espécie nativa do Cerrado, endêmica da cadeia do espinhaço e altamente aromática, cujo óleo essencial possui propriedades medicinais de alto valor farmacológico, mas, por tratar-se de uma espécie não domesticada, pouco se sabe quanto a sua propagação. Devido a sua importância, objetivou-se avaliar o efeito do condicionamento osmótico sobre a qualidade física e fisiológica de suas sementes. O delineamento experimental foi o inteiramente casualizado com quatro repetições de 100 sementes, sendo que os tratamentos consistiram em dois tipos de sementes (com e sem tegumento) submetidas a dez tempos de embebição em água (0, 2, 4, 6, 12, 24, 48, 72, 96 e 120 horas). Após cada período, as sementes foram submetidas ao teste de condutividade elétrica e de germinação. Entre a condutividade elétrica e a porcentagem de germinação há relação diretamente proporcional, enquanto o melhor tempo de condicionamento osmótico é alcançado nas sementes com tegumento e imersas em água, durante 48 horas.

Biochemical behavior of bean seeds and grains during storage / Comportamento bioquímico de sementes e grãos de feijão durante o armazenamento

The development of researches about vigor provides greater insight about the physiological behavior of seeds over storage periods. The aim of this study was to evaluate the biochemical changes which occurred in beans stored for 360 days. Analyses were performed at 0, 30, 90, 180, 270, and 360 days after receiving the seeds (S1 and S2) and grains (G1 and G2) of BRS Splendor. The following tests were conducted: water content, electrical conductivity, and chemical composition of the soaking solution, where sugars and ions Fe2+, Zn, Ca2+, Mg2+ and K+ were quantified. The experimental design was completely randomized split-plot and means were compared through Tukey test (p>0.05). Water content decreased after 90 days, and after 180 days reached an average of 16%. The electrical conductivity showed the greatest loss of solute after 90 days. Larger amounts of soluble sugars were found in S1 and G1. The quantities of potassium and calcium decreased after 360 days, while magnesium increased after 90 days of storage. The electrical conductivity test showed no direct relation to the quantification of the investigated ions. The amount and behavior of amino acids and studied ions did not showed relation to the decrease in vigor of beans.

O desenvolvimento de pesquisas sobre vigor proporciona maior conhecimento sobre o comportamento fisiológico das sementes ao longo do armazenamento. O objetivo desse estudo foi avaliar as mudanças bioquímicas ocorridas em feijões armazenados por 360 dias. As análises foram realizadas aos 0, 30, 90, 180, 270 e 360 dias, após o recebimento das sementes e grãos da cultivar BRS Esplendor. Foram realizados os testes de teor de água, condutividade elétrica, e a composição química da solução de embebição, onde os teores de açúcares e íons Fe2+, Zn, Ca2+, Mg2+ e K+ foram quantificados. O delineamento foi inteiramente casualizado em esquema de parcelas subdivididas e as médias comparadas pelo teste de Tukey (p>0,05). A condutividade elétrica apresentou maior perda de solutos aos 90 dias. As quantidades de potássio e cálcio diminuíram até os 360 dias, enquanto o magnésio teve aumento após 90 dias de armazenamento. O teste de condutividade elétrica não apresentou relação direta com a quantificação dos íons investigados. A quantidade e o comportamento dos aminoácidos e dos íons estudados não demonstraram relação com a queda do vigor dos feijões.

Ion association of glycine, α-alanine and β-alanine in water and water+ D-glucose mixtures at different temperatures.

The conductance of glycine, α-alanine and β-alanine has been measured in the concentration range of 1×10-2 to 8×10-2 mol dm-3 in aqueous and aqueous binary mixtures containing D-glucose (5,10,15,20% (w/w)) at different temperatures (298.15-313.15 K). The conductance data in all cases have been computed by Shedlovsky equation to obtain Λ0 m and KA . Based upon the composition dependence of Walden product, the influence of the Dglucose mixtures on the solvation of ions has been discussed. The values of the association constants, KA, are used to obtain various thermodynamic parameters for the association process in the solution.

Accuracy of Root ZX in teeth with simulated root perforation in the presence of gel or liquid type endodontic irrigant

OBJECTIVES: To evaluate the accuracy of the Root ZX in teeth with simulated root perforation in the presence of gel or liquid type endodontic irrigants, such as saline, 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine liquid, 2% chlorhexidine gel, and RC-Prep, and also to determine the electrical conductivities of these endodontic irrigants. MATERIALS AND METHODS: A root perforation was simulated on twenty freshly extracted teeth by means of a small perforation made on the proximal surface of the root at 4 mm from the anatomic apex. Root ZX was used to locate root perforation and measure the electronic working lengths. The results obtained were compared with the actual working length (AWL) and the actual location of perforations (AP), allowing tolerances of 0.5 or 1.0 mm. Measurements within these limits were considered as acceptable. Chi-square test or the Fisher's exact test was used to evaluate significance. Electrical conductivities of each irrigant were also measured with an electrical conductivity tester. RESULTS: The accuracies of the Root ZX in perforated teeth were significantly different between liquid types (saline, NaOCl) and gel types (chlorhexidine gel, RC-Prep). The accuracies of electronic working lengths in perforated teeth were higher in gel types than in liquid types. The accuracy in locating root perforation was higher in liquid types than gel types. 5.25% NaOCl had the highest electrical conductivity, whereas 2% chlorhexidine gel and RC-Prep gel had the lowest electrical conductivities among the five irrigants. CONCLUSIONS: Different canal irrigants with different electrical conductivities may affect the accuracy of the Root ZX in perforated teeth.

Comparação entre métodos para a avaliação do vigor de lotes de sementes de triticale / Comparison of methods for assessing the vigor of seed lots of triticale

Dentro de um programa de controle de qualidade, a avaliação do vigor de sementes é fundamental e necessária para o sucesso da produção. Este trabalho teve como objetivo avaliar a eficiência de diferentes testes de vigor na avaliação da qualidade fisiológica de sementes de triticale (X. triticosecale Wittmack), buscando a diferenciação de lotes. Cinco lotes da cultivar 'IPR 111' foram submetidos ao teste de germinação, primeira contagem, teste de frio, condutividade elétrica (50 sementes 50mL-1 de água; 25°C 24h-1), lixiviação de potássio (50 sementes 75mL-1 de água; 25°C 3h-1), envelhecimento acelerado (43°C 48h-1) e teor de água. O teste de condutividade elétrica e lixiviação de potássio são eficientes na diferenciação do vigor de lotes de sementes de triticale.

In a program of seed quality assurance, the evaluation of seed vigor is fundamental and necessary to the global production process outcome. The objective of this experiment was to verify the efficiency of different vigor tests for evaluation of triticale seeds (X. triticosecale Wittmack) seeking the lots differentiation. Five lots of triticale seeds (cv. IPR 111) were submitted to the following evaluations: germination, first counting of germination test, cold test, electrical conductivity test (50 seeds into 50ml of water, at 25°C for 24 hours), accelerated aging test (43°C 48h-1) in distilled water (100 percent RH), and also seed water content. The test of electrical conductivity and potassium leaching was efficient to distinguish vigor of triticale.