Occurrence of Belonolaimus in Sinaloa, Northwestern Mexico: A New Report on Distribution and Host Range.

The present study reports the occurrence of the genus Belonolaimus in the state of Sinaloa, Mexico, associated with native plants (i.e., Ziziphus amole and Stenocereus alamosensis) in a natural coastal ecosystem. Both morphological and molecular approaches were employed to characterize the Sinaloa population. Notwithstanding of some morphological and morphometric variation between Belonolaimus from Sinaloa and other valid species, the characterization indicates that this population might belong to the Belonolaimus longicaudatus species complex. Molecular analyses based on the 28S gene and ITS1-5.8S-ITS2 regions of the ribosomal RNA (rRNA) identified four major clades within Belonolaimus; however, none of the species including B. longicaudatus, B. gracilis, and B. euthychilus were supported as monophyletic; yet monophyly is argued to be a basic requirement of species status. Sequence divergence among different Belonolaimus populations and species varied according to the rRNA dataset (i.e., ITS1-5.8S-ITS2 > 28S > 18S) used, thus showing the importance of using genes with different rates of evolution to estimate species relationships. The fact that Belonolaimus has not been found in other cultivated (including on suitable hosts) areas in Sinaloa and that this population is relatively distant from the common B. longicaudatus groups (i.e., clades A and B) suggests that its appearance was not due to a recent introduction associated with the local agriculture.

First Direct-Detection Constraints on eV-Scale Hidden-Photon Dark Matter with DAMIC at SNOLAB.

We present direct detection constraints on the absorption of hidden-photon dark matter with particle masses in the range 1.2-30 eV c^{-2} with the DAMIC experiment at SNOLAB. Under the assumption that the local dark matter is entirely constituted of hidden photons, the sensitivity to the kinetic mixing parameter κ is competitive with constraints from solar emission, reaching a minimum value of 2.2×10^{-14} at 17 eV c^{-2}. These results are the most stringent direct detection constraints on hidden-photon dark matter in the galactic halo with masses 3-12 eV c^{-2} and the first demonstration of direct experimental sensitivity to ionization signals <12 eV from dark matter interactions.

Equation of state and critical point behavior of hard-core double-Yukawa fluids.

A theoretical study on the equation of state and the critical point behavior of hard-core double-Yukawa fluids is presented. Thermodynamic perturbation theory, restricted to first order in the inverse temperature and having the hard-sphere fluid as the reference system, is used to derive a relatively simple analytical equation of state of hard-core multi-Yukawa fluids. Using such an equation of state, the compressibility factor and phase behavior of six representative hard-core double-Yukawa fluids are examined and compared with available simulation results. The effect of varying the parameters of the hard-core double-Yukawa intermolecular potential on the location of the critical point is also analyzed using different perspectives. The relevance of this analysis for fluids whose molecules interact with realistic potentials is also pointed out.

Diversidade de predadores em coentro, endro e funcho sob manejo orgânico / Diversity of predators in coriander, dill and fennel under organic manegement

Espécies vegetais da família Apiaceae podem proporcionar recursos vitais para insetos predadores de pragas agrícolas, promovendo sua eficiência como agentes de controle biológico devido à oferta de recursos como sítios de refúgio, proteção e alimentação. Assim, o objetivo deste trabalho foi avaliar a atração de insetos predadores pelas apiáceas coentro (Coriandrum sativum L.), endro (Anethum graveolens L.) e funcho (Foeniculum vulgare Mill.). O experimento foi conduzido no campus da Universidade Federal de Lavras (UFLA), Lavras, MG, em blocos completos ao acaso, com três tratamentos e quatro repetições. Coletas semanais foram realizadas por meio de batida das plantas em bandejas, sendo os predadores aspirados e acondicionados em frascos com álcool 70%. Determinaram-se a curva do coletor, a riqueza de espécies, o índice de diversidade de Shannon-Wienner e o índice de similaridade (análise de Cluster). O funcho apresentou maior índice de Shannon-Wienner (H’ = 1,104) e riqueza, enquanto o coentro mostrou maior abundância, sobretudo para a espécie Orius insidiosus (Hemiptera: Anthocoridae), um importante predador de tripes em hortaliças. Outras espécies predadoras de pragas de hortaliças foram encontradas, de maneira geral, em todas as apiáceas, destacando-se os adultos e larvas de coccinelídeos, importantes predadores de pulgões. A análise de Cluster indicou maior similaridade entre funcho e endro (55,03%). O período de floração promoveu considerável aumento na abundância de predadores, sobretudo no coentro.

Species of plants of the Apiaceae family can provide vital resources for predators of agricultural pests, boosting their efficiency as biological control agents, because they allow their maintenance in the environment by offering features such as sites of refuge, protection and food. The present study was aimed to evaluate the attraction of predator insects by 3 Apiaceae species, namely coriander (Coriandrum sativum L.), dill (Anethum graveolens L.) and fennel (Foeniculum vulgare Mill.). The bioassay was conducted on the campus of UFLA (MG) in a randomized block design with 3 treatments and 4 replications. Weekly collections were carried out by beating the plants on white plastic trays, aspirating the predators and packing them into bottles with 70% alcohol. Determinations were made of the collector curve, the species richness, the Shannon-Wienner diversity index and the index of similarity (cluster analysis). The fennel had a higher richness and Shannon-Wienner index (H’ = 1.104), while the coriander was more abundant, especially for the species Orius insidiosus (Hemiptera: Anthocoridae), a major predator of thrips in vegetables. Other predatory species of vegetable pests were found, generally, on all Apiaceae, especially adults and larvae of coccinellids, which are important predators of aphids. Cluster analysis indicated a greater similarity between fennel and dill (55.03%), and a lower value for the other pairs. The flowering period increased the abundance of predators, especially the coriander.

Diversidade de predadores em coentro, endro e funcho sob manejo orgânico / Diversity of predators in coriander, dill and fennel under organic manegement

Espécies vegetais da família Apiaceae podem proporcionar recursos vitais para insetos predadores de pragas agrícolas, promovendo sua eficiência como agentes de controle biológico devido à oferta de recursos como sítios de refúgio, proteção e alimentação. Assim, o objetivo deste trabalho foi avaliar a atração de insetos predadores pelas apiáceas coentro (Coriandrum sativum L.), endro (Anethum graveolens L.) e funcho (Foeniculum vulgare Mill.). O experimento foi conduzido no campus da Universidade Federal de Lavras (UFLA), Lavras, MG, em blocos completos ao acaso, com três tratamentos e quatro repetições. Coletas semanais foram realizadas por meio de batida das plantas em bandejas, sendo os predadores aspirados e acondicionados em frascos com álcool 70%. Determinaram-se a curva do coletor, a riqueza de espécies, o índice de diversidade de Shannon-Wienner e o índice de similaridade (análise de Cluster). O funcho apresentou maior índice de Shannon-Wienner (H = 1,104) e riqueza, enquanto o coentro mostrou maior abundância, sobretudo para a espécie Orius insidiosus (Hemiptera: Anthocoridae), um importante predador de tripes em hortaliças. Outras espécies predadoras de pragas de hortaliças foram encontradas, de maneira geral, em todas as apiáceas, destacando-se os adultos e larvas de coccinelídeos, importantes predadores de pulgões. A análise de Cluster indicou maior similaridade entre funcho e endro (55,03%). O período de floração promoveu considerável aumento na abundância de predadores, sobretudo no coentro.(AU)

Species of plants of the Apiaceae family can provide vital resources for predators of agricultural pests, boosting their efficiency as biological control agents, because they allow their maintenance in the environment by offering features such as sites of refuge, protection and food. The present study was aimed to evaluate the attraction of predator insects by 3 Apiaceae species, namely coriander (Coriandrum sativum L.), dill (Anethum graveolens L.) and fennel (Foeniculum vulgare Mill.). The bioassay was conducted on the campus of UFLA (MG) in a randomized block design with 3 treatments and 4 replications. Weekly collections were carried out by beating the plants on white plastic trays, aspirating the predators and packing them into bottles with 70% alcohol. Determinations were made of the collector curve, the species richness, the Shannon-Wienner diversity index and the index of similarity (cluster analysis). The fennel had a higher richness and Shannon-Wienner index (H = 1.104), while the coriander was more abundant, especially for the species Orius insidiosus (Hemiptera: Anthocoridae), a major predator of thrips in vegetables. Other predatory species of vegetable pests were found, generally, on all Apiaceae, especially adults and larvae of coccinellids, which are important predators of aphids. Cluster analysis indicated a greater similarity between fennel and dill (55.03%), and a lower value for the other pairs. The flowering period increased the abundance of predators, especially the coriander.(AU)

Diversidade de predadores em coentro, endro e funcho sob manejo orgânico

Species of plants of the Apiaceae family can provide vital resources for predators of agricultural pests, boosting their efficiency as biological control agents, because they allow their maintenance in the environment by offering features such as sites of refuge, protection and food. The present study was aimed to evaluate the attraction of predator insects by 3 Apiaceae species, namely coriander (Coriandrum sativum L.), dill (Anethum graveolens L.) and fennel (Foeniculum vulgare Mill.). The bioassay was conducted on the campus of UFLA (MG) in a randomized block design with 3 treatments and 4 replications. Weekly collections were carried out by beating the plants on white plastic trays, aspirating the predators and packing them into bottles with 70% alcohol. Determinations were made of the collector curve, the species richness, the Shannon-Wienner diversity index and the index of similarity (cluster analysis). The fennel had a higher richness and Shannon-Wienner index (H' = 1.104), while the coriander was more abundant, especially for the species Orius insidiosus (Hemiptera: Anthocoridae), a major predator of thrips in vegetables. Other predatory species of vegetable pests were found, generally, on all Apiaceae, especially adults and larvae of coccinellids, which are important predators of aphids. Cluster analysis indicated a greater similarity between fennel and dill (55.03%), and a lower value for the other pairs. The flowering period increased the abundance of predators, especially the coriander.

Espécies vegetais da família Apiaceae podem proporcionar recursos vitais para insetos predadores de pragas agrícolas, promovendo sua eficiência como agentes de controle biológico devido à oferta de recursos como sítios de refúgio, proteção e alimentação. Assim, o objetivo deste trabalho foi avaliar a atração de insetos predadores pelas apiáceas coentro (Coriandrum sativum L.), endro (Anethum graveolens L.) e funcho (Foeniculum vulgare Mill.). O experimento foi conduzido no campus da Universidade Federal de Lavras (UFLA), Lavras, MG, em blocos completos ao acaso, com três tratamentos e quatro repetições. Coletas semanais foram realizadas por meio de batida das plantas em bandejas, sendo os predadores aspirados e acondicionados em frascos com álcool 70%. Determinaram-se a curva do coletor, a riqueza de espécies, o índice de diversidade de Shannon-Wienner e o índice de similaridade (análise de Cluster). O funcho apresentou maior índice de Shannon-Wienner (H' = 1,104) e riqueza, enquanto o coentro mostrou maior abundância, sobretudo para a espécie Orius insidiosus (Hemiptera: Anthocoridae), um importante predador de tripes em hortaliças. Outras espécies predadoras de pragas de hortaliças foram encontradas, de maneira geral, em todas as apiáceas, destacando-se os adultos e larvas de coccinelídeos, importantes predadores de pulgões. A análise de Cluster indicou maior similaridade entre funcho e endro (55,03%). O período de floração promoveu considerável aumento na abundância de predadores, sobretudo no coentro.

A plausible explanation for heart rates in mammals.

We consider a simple model to give a plausible mechanical explanation of what are the actual resting heart rates of mammals optimized for. We study what is the optimal frequency for a viscoelastic fluid circulating in a pulsatile way through a network of tubes and conclude that the heart rate is not optimized to transport blood through the whole net. Rather, actual resting heart rates of mammals happen at frequencies that optimize flow in vessels of radii that correspond to large arteries, which bring oxygenated blood rapidly far away from the heart, towards head and limbs. Our results for the optimal frequencies, obtained using observed radii of femoral arteries in mammals, agree best with the heart rates observed. We find a theoretical allometric relation between optimal flow frequency and radius: nu approximately R(-1). This one, agrees with the exponent obtained when plotting observed heart rates versus radii of both, femoral arteries and carotids in mammals of different sizes, from mice to horses.

Equation of state of additive hard-disk fluid mixtures: a critical analysis of two recent proposals.

A detailed analysis of two different theoretical equations of state for a binary mixture of additive hard disks [C. Barrio and J. R. Solana, Phys. Rev. E 63, 011201 (2001); A. Santos, S. B. Yuste, and M. López de Haro, Mol. Phys. 96, 1 (1999)], including their comparison with Monte Carlo results, is carried out. It is found that both proposals, which require the equation of state of the single-component system as input, lead to comparable accuracy when the same input is used in both, but that advocated by Santos et al. is simpler and complies with the exact limit in which the small disks are point particles.

[Chromium content in foods and dietary intake estimation in the Northwest of Mexico]. / Contenido de cromo en alimentos y estimación de su ingestión dietaria en el noroeste de México.

Chromium is an indispensable nutrient for the carbohydrates and lipids metabolism. In this study the chromium content in the twenty main foods of the diet from Northwestern Mexico was determined, as well as the daily mean intake which was estimated based on the food intake basket of this region. Chromium content was analyzed by atomic absorption spectrophotometry using the graphite furnace technique and previous digestion of foods in microwave oven. The chromium mean intake was estimated considering the chromium daily mean intake for person per day and the chromium content of the foods analyzed in this study. The range chromium content in the foods analyzed was between 0.0004 and 0.1641 microgram/g dry weight. White cheese showed the highest chromium content followed by pasta soup, wheat tortilla, bread and meat. The main foods chromium contributors in the diet were: wheat tortilla (20%), white cheese (11%), corn tortilla (11%), pasta soup (10%), milk (10%), meat (9%) and white bread (8%). The daily chromium intake was 30.43 +/- 1.6 micrograms/d. Chromium values obtained in the food analyzed are considered low. Moreover, chromium intake obtained from the diet is not enough to meet the safety and adequate daily chromium intake. Therefore, the population from the Northwestern Mexico has a suboptimal dietary chromium intake.

[Fluoride intake and excretion in children of Hermosillo, Sonora, Mexico]. / Ingestión y excreción de fluoruros en niños de Hermosillo, Sonora, México.

OBJECTIVE: To estimate the fluoride intake and urinary excretion among 8-9 year-old school children. MATERIALS AND METHODS: A cross-sectional study was conducted from February to November 1997. Study subjects were 31 male children from Hermosillo, Mexico, living in three neighborhoods with different drinking water fluoride levels. Fluoride intake was measured through water intake and collection of food samples ingested in 24 hr. Fluoride excretion was measured in 24-hour urine samples. The fluoride concentration was measured by the potentiometer method using a fluoride-specific ion electrode. RESULTS: Statistically significant differences of fluoride levels in drinking water were found in the 3 different neighborhoods: 2.77, 0.78 and 0.54 mg/L, respectively (p < 0.01). The daily mean intake of fluoride for the neighborhood with the highest fluoride level was 5.41 mg/d, while mean intakes for the other two neighborhoods were 2.31 and 1.51 mg/d, respectively. Thirty-two percent of the children had fluoride intake above the recommendation values for this age group; sixty per cent of these children lived in the neighborhood with the highest fluoride level. Drinking water accounted for 63% of total fluoride intake, and the mean water intake was 1.8 liters. The mean excretion of fluoride was 1.61 mg/24 hours (range 0.18 to 8.1 mg/24 hr). Stepwise multiple regression showed an association between drinking water fluoride and fluoride urinary excretion (R2 = 0.56 p < 0.001). CONCLUSIONS: Fluoride intake in the neighborhood with the highest fluoride level was twice the daily recommended value for 8-9 year-old children. Drinking water was the main source of fluoride intake. The English version of this paper is available at: http://www.insp.mx/salud/index.html.

Relaxation in kinetic models on alternating linear chains.

A restricted dynamics, previously introduced in a kinetic model for relaxation phenomena in linear polymer chains, is used to study the dynamic critical exponent of one-dimensional Ising models. Both an alternating isotopic chain and an alternating-bond chain are considered. In contrast with what occurs for Glauber dynamics, in these two models the dynamic critical exponent turns out to be the same. The alternating isotopic chain with the restricted dynamics is shown to lead to Nagel scaling for temperatures above some critical value. Further support is given relating the Nagel scaling to the existence of multiple (simultaneous) relaxation processes, the dynamics apparently not playing the most important role in determining such scaling.

Nagel scaling, relaxation, and universality in the kinetic ising model on an alternating isotopic chain

The dynamic critical exponent and the frequency and wave-vector dependent susceptibility of the kinetic Ising model on an alternating isotopic chain with Glauber dynamics are examined. The analysis provides a connection between a microscopic model and the Nagel scaling curve originally proposed to describe dielectric susceptibility measurements of several glass-forming liquids. While support is given to the hypothesis relating the Nagel scaling to multiple relaxation processes, it is also found that the scaling function may exhibit plateau regions and does not hold for all temperatures.

[Chemical composition of a typical bread and its energy and protein supply in the population from the northeast of Mexico]. / Composición química del pan tradicional e industrial y su aporte de energía y proteína en la población del Noroeste de México.

Bread from wheat flour is one of the most widely consumed products by the Mexican population. In this study, proximate composition, and mineral content were determined, and cost per/gram of protein and energy of traditional and industrial bread were compared. Seven types of bread were analyzed: bolillo, virginia, white bread and pastries conchita, croissant, breadroll and donuts. Products were analyzed for proximate composition by official methods, and content of Na, K, Ca, Mg, Fe, y Zn by atomic absorption spectrometry. Based on 24 hour recall interviews, the consumption of each type of bread as well as the percent of protein and energy allowances were calculated. Significant differences (p < 0.05) were found with respect to nutrient content between traditional and industrial breads. White bread and pastries from industrial origin showed higher costs (p < 0.05) per gram of protein and energy than traditional products in most cases. Both industrial and traditional breads showed higher fat content than that established by Official Mexican regulations. A high content of Ca was found in bread from the industrial origin and K, Mg, Fe y Zn were higher (p < 0.05) than those from the traditional bakery.

[Intake of dietary fiber, sodium, potassium, and calcium and its relation with arterial blood pressure in normotensive adult men]. / Consumo de fibra dietética, sodio, potasio y calcio y su relación con la presión arterial en hombres adultos normotensos.

OBJECTIVE: To evaluate the effect of dietary fiber, energy, sodium, calcium and potassium intake on the blood pressure of a group of normotensive adults. MATERIAL AND METHODS: Subjects were 38 healthy normotensive adult males aged 30-45 years, resident of Hermosillo, Sonora, Mexico. Blood pressure, diet, anthropometric data and physical activity were recorded. RESULTS: Their diet was high in fiber and fat. Sodium intake was 56% above the recommended values in 87% of the subjects, and the variable with the highest correlation to diastolic blood pressure. Of the subjects, 36.9% were overweight and obese, and a significant statistic association was found between BMI and diastolic and systolic blood pressure. CONCLUSIONS: A significant relationship was found between hypertension and high consumption of sodium, overweight and obesity in healthy adult normotensive males.

[Chemical composition, dietary fiber and mineral content of frequently consumed foods in northwest Mexico]. / Composición química, fibra dietética y contenido de minerales en alimentos de consumo frecuente en el noroeste de México.

Nutrient composition in foods is very important specially in evaluation of nutritional status in populations. In this study the proximate composition, dietary fiber (DF) and mineral content of 15 frequently consumed foods in Northwest Mexico were determined. The procedures used were AOAC (1984) official methods, chemical-enzymatic method for DF and atomic absorption spectrophometry for minerals. Foods were grouped into cereals, legumes, meat and dairy products, fat was the most variable component in all foods (0,41 to 21,1 g/100 g). Fired beans (Phaseolus vulgaris: variedad pinto) had the highest DF content (9,21 g/100g); as is basis). Sodium among the minerales was also highly variable mainly due to the addition of salt during preparation of foods, except in corn tortillas were salt is not added. In contrast wheat flour tortillas had the highest sodium content of the foods analysed. Fresh white cheese had the highest calcium content (563 mg/100g). The meat group had the highest content of Fe and Zn (2,4-5,4 and 4,2-5,4 mg/100 g respectively). This study has provided information with current analytical techniques of important foods in northwest Mexico that will contribute to food composition tables in Latin America.

[Sodium, potassium and calcium content in regional dishes consumed in Sonora, Mexico]. / Contenido de sodio, potasio y calcio en platillos tipicos consumidos en Sonora, México.

The content of sodium, potassium and calcium was determined in 15 regional dishes, by atomic absorption spectrophotometry. The Na:K ratio was high in most of the dishes due to the high sodium content and low content of potassium found. The higher sources of the studied minerals were "tortilla de harina" with 1,372.8 mg/100 g of sodium; "chorizo con papas" with 466 mg/100 g of potassium, and "calabacitas con queso" with 244.1 mg/100 g of calcium. Two of the dishes considered as desserts, "capirotada" and "arroz con leche" showed the lowest Na:K ratio (0.66 and 0.81, respectively).