bluuebunny/crossref_metadata_2025_split huggingface dataset:
Meta‐Analyses of Biosolids Effect in Dryland Wheat Agroecosystems
Authors: Barbarick Kenneth , Ippolito James , McDaniel Jacob 
Published: March 2017

Land application to cropping systems is USEPA's preferred method of recycling biosolids. Determination of biosolids effect size through meta‐analyses from two decades of field‐location research at three sites should answer the question: Does 20 yr of biosolids application affect dryland wheat (Triticum aestivum L.) grain production, grain nutrient concentrations, and soil elemental extractability compared with equivalent rates of commercial N fertilizer? At two sites, biennial biosolids application rates to a wheat–fallow (WF) rotation were up to 11.2 dry Mg ha−1 and up to 112 kg commercial N fertilizer ha−1, whereas rates at the third location varied to match soil‐test information. Crop rotations included WF and wheat–corn (Zea mays L.)–fallow. We completed meta‐analyses of biosolids effects compared with N fertilizer on wheat yield, grain protein, grain total, and soil ammonium bicarbonate‐diethylenetriaminepentaacetic acid (ABDTPA)‐extractable P, Zn, Cu, Fe, and Ni concentrations at the aforementioned sites from 1993 through 2013. Results showed that biosolids produced greater grain P and Zn at one site. Biosolids rates at two sites resulted in greater grain Zn and ABDTPA P, Zn, Cu, and Fe. Meta‐analyses tests for heterogeneity indicated that the variance for all sites and rates could be explained as consistent across treatments, whereas the test for the 20 yr showed that heterogeneity was large and other factors affected the variance (e.g., climatic variability between years). Meta‐analysis showed the practical effect of biosolids over a 20‐yr study and demonstrated that the primary biosolids effect was an improvement in Zn availability to wheat.Core Ideas
Meta‐analyses provided effect size for wheat yield and grain and ABDTPA concentrations.
Grain and ABDTPA levels were increased by biosolids application compared to N rates.
Inconsistent results over years were probably due to climatic vagaries.
Characteristics of Soil Evaporation and Temperature under Aggregate Mulches Created by Burrowing Ants (Camponotus japonicus)
Authors: Li Tongchuan , Shao Ming'an , Jia Yuhua 
Published: March 2017

Core Ideas
We studied a new material of mulch made by soil‐dwelling ants.
Ants burrowed aggregates significantly affected soil evaporation and temperature.
Hydrolyzed aggregates could not restrain soil evaporation after rain.
Mulch on the soil surface is an effective practice for conserving soil moisture. In this study, we assessed the effects of aggregate mulches created by burrowing ants (Camponotus japonicus) on soil evaporation and temperature. A series of simulation experiments were conducted using buckets (20 cm diameter × 20 cm height) filled with loess soil (7.3 kg). Seven ant populations (0, 10, 30, 50, 100, 150, and 200) and four mulch thicknesses (0 [bare soil], 3, 6, and 9 mm) were used to evaluate the effects of ant abundance and mulch thickness on soil evaporation rates and temperature. The evaporation rate and temperature were measured with an electronic scale (with 1 g precision) and electronic thermometers (with 0.1°C precision). The number of aggregates was linearly correlated with the number of introduced ants (R2 = 0.8927). A negative relationship existed between the soil evaporation rate and a mulch thickness of 0 to 9 mm when the soil moisture was higher than 8.4%. Furthermore, the function of aggregate mulches on restraining evaporation was highest between 1130 and 1330 h on sunny days. When the solar radiation and the soil moisture were at a low level, minimal difference was observed in the evaporation rates among the treatments. For the soil temperature, aggregate mulches were more sensitive to the intercepted heat, resulting in higher temperatures on the mulch surface than on the bare soil. Moreover, the effects of the aggregate mulches on soil evaporation and temperature were weakened when the aggregates disintegrated. The findings in this research are helpful for understanding the evaporation process in loess soils with burrowing ants. Maintaining a large number of burrowing ants or a relative constant cover of ant‐derived aggregates on the soil surface could restrict soil evaporation.
Apparent Stability and Subtle Change in Surface and Subsurface Soil Carbon and Nitrogen under a Long‐Term Fertilizer Gradient
Authors: Collier Sarah M. , Ruark Matthew D. , Naber Mack R. , Andraski Todd W. , Casler Michael D. 
Published: March 2017

Core Ideas
Long‐term fertilizer rate affected soil properties to 1 m under continuous corn.
Inorganic N fertilization was a benefit rather than a detriment to soil C and N.
The most productive treatments maintained but did not build soil C and N.
All fertilizer rate treatments had less topsoil than the field edge.
Uncertainty exists regarding the depth and extent to which agricultural practices affect soil properties, in particular soil organic C (SOC). In this study we examined the impact of 53 yr of continuous corn (Zea mays L.) receiving varying rates of inorganic N fertilizer with complete stover return on soil properties including SOC, total N, and bulk density (BD) to a depth of 1 m. In the treatment receiving virtually no applied N there was a significant reduction in soil N content at 0 to 30 cm over the study period, while the treatment receiving N in excess of recommended application levels was similar to the treatment receiving recommended rates of N fertilizer. Trends in SOC content were similar to those for total N, but a significant treatment effect was detectable throughout the entire 1‐m soil profile sampled. Over the course of the study, all experimental fields appeared to have lost approximately 6 cm of topsoil through erosion, with the lowest N rate plots subsiding a further 2 cm due to compaction. Despite using disruptive management practices (moldboard plowing and application of anhydrous ammonia), declines in soil C and N content were not apparent for this soil type under conditions of low slope and the linear gains in productivity realized under the two higher N rate treatments. Thus N fertilizer was a benefit to this cropping system, rather than a detriment, and was sufficient to allow maintenance—but not building—of SOC.
Consumo voluntario de alimento fresco por parte de monos aulladores (Alouatta palliata y A. pigra) en cautiverio
Authors: Anaya Lira Maribel , Gutiérrez Olvera Carlos , Ducoing Watty Adriana Margarita , Cifuentes Calderón Perla , Sánchez Trocino Mariano 
Published: March 2017

Se tomaron como sujetos de estudio a los monos saraguatos (Alouatta pigra y A. palliata) que se encuentran en el Zoológico de Chapultepec en la Ciudad de México. El muestreo se realizó durante siete días consecutivos. Se obtuvo diariamente el peso en gramos del alimento ofrecido y rechazado por jaula, con el objetivo de determinar la cantidad de alimento fresco (AF) consumido y rechazado en promedio por animal por día. Los resultados obtenidos se muestran en promedio por día por animal por jaula debido a que no se encontraron diferencias estadísticamente significativas en el consumo promedio por ingrediente y total por animal por jaula (p>0,05) en los días estudiados. Los resultados mostraron un consumo de alimento promedio por animal por día de 844,06±35,90g de AF, el cual corresponde al 12,23±1,52% respecto de su peso vivo (PV), lo que muestra un menor consumo de acuerdo a lo reportado por Milton en 1979 que es del 15% PV. El desperdicio por animal por día fue de 551,04±35,94g de AF al día que corresponde a un 39,49±2,38% de AF. El alto porcentaje de rechazo del alimento puede deberse al comportamiento alimenticio propio de la especie. PALABRAS CLAVEAlouatta, volunteer consume, captive, howler monkey, fresh food
A case study in Costa Rica about personal happiness: Does health and family communication have more influence than quantity of money and material goods?
Authors: Pentz Carliann J. , Rojas Daniel , McCoy Michael B. , Vaughan Christopher S. 
Published: March 2017

From extensive research on the phenomenom of “simpatía”, known as a relationship or an affinity between people or things in which whatever affects one correspondingly affects the other, in Latin American countries, many characteristics, such as friendliness and a positive attitude, have been identified. However, despite such positive attitudes, very few studies measured levels of happiness and satisfaction in these communities, specifically Costa Rica. This study measured happiness levels during March-April 2012 in San Ramón, Costa Rica. Created questionnaires measuring happiness levels were distributed to 197 participants (104 M, 92 F, 1 Unknown). A validated questionnaire showed homogeneity to our created questionnaire (P<0,0001). Mean responses relating happiness to “good health” (=4,73) and “family communication” (= 4,58) were greater than responses of “quantity of money made each month” (= 3,49) or “owning material goods” (= 3,49) (P<0,05). Mean responses of “having a national army” (= 1,73) were smaller than responses to “living in nature” (= 4,62). On terms of gender and sexuality rights, most participants did not support the idea of homosexuality, and while equal gender rights was supported, more women than men felt happier by this concept (P=0,0004). The major limitation for this study was limited time, area, and the number of participants.KEY WORDSCosta Rica, family communication, good health, happiness levels, income levels, material possessions, simpatía
Análisis bacteriológico del arroz con leche expendido en el área metropolitana de Costa Rica
Authors: Carranza Freddy , Rivera Pablo , Chaves Carolina , Arias María Laura 
Published: March 2017

El arroz con leche es un alimento de consumo frecuente en la población costarricense que se prepara artesanal e industrialmente. Con el fin de conocer su calidad bacteriológica, se analizaron 50 muestras de arroz con leche de origen industrial así como 30 muestras del mismo producto pero de origen artesanal. Se realizó la determinación de indicadores de manipulación, contaminación, vida útil y patógenos incluyendo Staphylococcus aureus, Listeria monocytogenes y Bacillus cereus. Además, se determinó la presencia de los genes nhe A,B y C en las cepas de Bacillus cereus aislados, esto, utilizando la técnica de reacción en cadena de la Polimerasa (PCR). Un 38% de las muestras de origen industrial y 70% de las de origen artesanal mostró un recuento total aerobio mesófilo superior a 104 UFC/g, de la misma manera un 6% de las muestras de origen industrial y un 40% de las artesanales mostraron un recuento de bacterias lácticas superior a 104 UFC/g. Con respecto a coliformes totales, 14% de las muestras industriales y 70% de las artesanales superaron los 100 NMP/g. Un 8% de las muestras de origen industrial y 60% de las de origen artesanal presentó un NMP de coliformes fecales superior a 100. Se confirmó la presencia de Escherichia coli en 6% de las muestras industriales y 3,3% de las artesanales). Se pudo recuperar e identificar Bacillus cereus en un 8% de las muestras de origen industrial y en 13% de las de origen artesanal. En tres de las cepas de origen industrial y todas las de origen artesanal se determinó la presencia de genes nheA, nheB y nheC No se detectó la presencia de Staphylococcus aureus ni de Listeria monocytogenes.PALABRAS CLAVEArroz con leche, calidad bacteriológica, Bacillus cereus, Liseria monocytogenes, nheA, B and C.
Patrones diarios de actividad de la hormiga Azteca constructor (Hymenoptera: Formicidae) y su relación con la presencia de alimento
Authors: Gutiérrez-Martínez Pablo R. , Acuña-Sánchez Diana 
Published: March 2017

La actividad de las hormigas, al igual que en el resto de los seres vivos, presenta variaciones rítmicas que sugieren un sistema cronobiológico integrado o ciclo diario sincronizado con las variaciones geofísicas de la Tierra. Estudios previos en hormigas han demostrado que la actividad de las colonias puede variar entre estaciones, a lo largo del día y a la oferta de alimento de la planta a la que la colonia se encuentra vinculada. El presente trabajo tiene como objetivos registrar los patrones de actividad diaria de Azteca constructor en condiciones de cautiverio y en el campo, y si su actividad varía ante la presencia de corpúsculos de Müller en los trichilia. Encontramos que la presencia de corpúsculos de Müller no afecta la actividad de las colonias y por tanto, esta tiene mayor relación al ritmo diario de la especie que a la presencia de alimento. En cuanto a los resultados a nivel general en las colonias en cautiverio la actividad mostró una tendencia mayor en las horas cercanas al mediodía, lo que sugiere una relación con el ciclo diario. La planta aumenta la producción de cuerpos Müller según aumenta la actividad de la hormiga. Además la relación de la hormiga con Pseudococidae pone en duda los beneficios que recibe la planta en su relación con Azteca. Finalmente, la actividad en las colonias en el campo varió mucho, lo que sugiere que durante estas observaciones no solo influyó el ritmo diario, sino que además hay un efecto de factores ambientales sobre la actividad de la hormiga.PALABRAS CLAVEPseudococcidae, cuerpos de Müller, trichilium, ciclo diario, fotoperiodo
Manejo exitoso de una inundación en el Herbario USJ de Costa Rica
Authors: Morales Carlos O. 
Published: March 2017

En noviembre de 2007 se rompió una cañería de agua potable en la Escuela de Biología, Universidad de Costa Rica, que provocó una inundación que afectó seriamente el Herbario USJ. Aquí comento las lecciones aprendidas y las claves del rescate exitoso de todos los especímenes montados, que estuvieron húmedos incluso más de una semana. PALABRAS CLAVEProtección de colecciones científicas, seguridad en herbarios, inundación, Herbario USJ, reparación de especímenes, Costa Rica
Population growth and cyst production of the rotifer Brachionus plicatilis (Monogonta: Brachionidae) fed with three different diets
Authors: Ortega-Salas A.A. , Reyes C.I. , Reyes-Bustamante H. 
Published: March 2017

This study compares the effect of different diets on population growth, fecundity rate, production, and cyst hatching efficiency of the rotifer Brachionus plicatilis. Microalgae were cultured using filtered and sterilized seawater at 25 and 26ºC. The volume of the containers for algae, bread yeast, and rotifer was duplicated daily from 31mL to 16L in nine days. Rotifers were cultured at 25°C and 35o/oo salinity. The mean values of daily population growth rate for the rotifers fed on C. muelleri, I. galbana and bread yeast were 0,91, 0,89 and 0,87 daily counts, respectively. After 10 cultured days, fecundity was 72%, 63% and 36% using C. muelleri, I. galbana and bread yeast, respectively. The highest mean value for cysts production was 4 064 000 cysts found from 63 243 (1,55%) rotifers fed on C. muelleri. Hatching efficiency after 36 hours of cysts from rotifers fed C. muelleri was 51 500 (94,3%) new borns, followed by 45 000 (93,3%) with I. galbana, and 31 000 (92,6%) with bread yeast. C. muelleri is a good food source for B. plicatilis.KEY WORDSFecundity, feeding, hatching, salinity, temperature
Sensorial descriptors for vegetarian pigeon pea hamburger patties according to a focus group
Authors: Mora Eliana , Andrés Carmen 
Published: March 2017

the Pigeon Pea is a legume that has become an alternative food security crop, associated with improvement of the soil, fodder, green manure and the protection of hidric basins. It is rich in vitaminsand proteins and considered nutritious for animals and humans. Four pilot plant tests with Costa Rican beans were done to produce an acceptableformulation of the hamburger patty. We preliminarily found that 15% of texturized soy, less than 1% of salt and 2% of Binder 2.0 were enough to create an acceptable patty for the consumer. Afterwards, afocus group of 12 people found that: a) the product belongs in four trends: good taste, ecology friendly, convenient and multipurpose;b) the target market can be children as well as adults or people withspecial needs (cholesterol, high blood pressure, diabetes); c) the sensorial descriptors were: healthy, non artificial flavors, with non transgenicsoy, with spices (like garlic, onion, basil and rosemary), biodegradable packaging material, transparent lid, and red and yellow or green andorange packaging material; d) can be sold in macrobiotics shops, supermarkets, restaurants and school cafeterias; e) presentation can be 4to 12 units with flavors like asparagus, mixed vegetables, palmetto and spinach. All participants reported good flavor, intermediate texture (rejectedby most), and good color and appearance (cooked and frozen). With additional study, the product can be sold commercially.
Impact of coastal shrimp fishing on women and youth livelihoods and food security in Tárcoles, Costa Rica
Authors: Judson Lucas , Solís Vivianne 
Published: March 2017

Fishing communities often face similar challenges that include overfishing, lack of food security, and unenforced sustainability policies. Tárcoles, mid-Pacific coast of Costa Rica, generates the majority of its income through fishing. A local cooperative aids families with direct marketing, lowering middleman power and generally benefitting the community. To understand the role of the shrimp Litopenaeus vannamei, we interviewed 47 women and youth (aged 13-72) and 41 young students (17-24) at the University of Costa Rica. We found that shrimp is a vital resource used both for food security and to improve economic situations of fishermen and women. People who have been fishing for more years perceive more positively the success of conservation efforts (P=0,05). Fishermen who have fished in more recent years also perceived greater success in shrimp recuperation in the town (P=0,03). At the University of Costa Rica, many students had at least a basic awareness of social and economic realities in rural fishing communities. Knowledge about artisanal fishing from UCR students was found to be very limited, with many respondents believing that artisanal fishing communities have no impact on large cities in Costa Rica. They should receive more education on this subject.
Isolation of two diatom species with aquaculture potential (Bacillariophyceae) from the Pacific of Costa Rica
Authors: Rodríguez-Núñez Karen , Toledo Pedro , Arias Sidey 
Published: March 2017

Due to the importance of primary production in the trophic network, most aquatic ecosystems rely on microalgae. However, there are fewer studies on phytoplankton in the Central American region, specifically on marine diatoms, in part because it is difficult to isolate and cultivate local species in tropical climates. The objective of this study is the isolation of two local diatoms of Chaetoceros and Nitzschia, potential food for aquatic organisms. Water samples was taken from the Nicoya Gulf, located in the Central Pacific coast of Costa Rica. The samples were successively filtered first through a 35µm pore size filter and then through one of 20µm. They were repeatedly isolated using modified Pasteur pipettes, and serial dilutions were done until a monoalgal culture was obtained. Two Bacillariophyceae were isolated: NGN1, genus Nitzschia; and CGN2, genus Chaetoceros. This study is a step toward reducing the importation of phytoplankton on feeding aquatic organisms by providing technical and scientific information to develop a microalgal culture from this region.
Body size of the gecko, Hemidactylus frenatus (Squamata: Gekkonidae) in the Coco’s Island National Park, Costa Rica
Authors: Villegas-Retana Sergio A , Durán-Apuy Alejandro , Picado-Rossi Adriana 
Published: March 2017

The gecko Hemidactylus frenatus reached Coco’s Island on boats. We captured 21 individuals and found that their snout-cloaca length ranged from 22,30mm to 47,85mm (0,1 g to 3,6 g).
Turismo sexual masculino en Costa Rica: espíritu de equipo, diálogo entre pares y papeles de género en una muestra grande de mensajes en un foro de Internet
Authors: Monge-Nájera Julián 
Published: March 2017

Hay pocos estudios científicos sobre el turismo sexual en Costa Rica. El estudio más importante sobre los turistas masculinos lo hizo Megan Rivers-Moore, quien implícitamente propuso varias hipótesis. Aquí analizo la totalidad de los mensajes del foro InternationalSexGuide.info entre el 2002 y el 2015, comparándolos con las hipótesis de Rivers-Moore, las categorías del “Prisma de Intimidad” de Milrod y Weitzer y datos de la literatura sobre mujeres que visitan Costa Rica para hacer turismo sexual. El análisis de los 4 409 mensajes muestra que los hombres dialogan, aconsejándose acerca de cómo obtener una visita satisfactoria a Costa Rica, visita que incluye sexo pagado pero no se limita a este objetivo únicamente. Las trabajadoras sexuales tienen poca interacción entre sí, pero los hombres se sienten parte de un grupo que intercambia información útil. El deseo de “Ser Tratado como Novio”, aunque no es predominante, es frecuente y se ajusta a la adaptación biológica propia del Homo sapiens en lo que respecta a interacciones de pareja. La mayoría de turistas masculinos hacen visitas cortas en las que tratan de interactuar inicialmente con varias mujeres para luego centrarse en aquellas con las que se sintieron mejor. Unos pocos casos evolucionan hacia una relación compleja que incluye el compromiso emocional. A pesar de la diferencia de poder financiero entre clientes y proveedores de servicios sexuales, los papeles tradicionales de género subyacen las relaciones, sean los turistas hombres o mujeres, lo que probablemente refleja una compleja combinación de factores biológicos y culturales.
Efecto de Geophila macropoda (Rubiaceae) como arvense de cobertura en la erosión hídrica en bananales de Guápiles, Limón, Costa Rica
Authors: Murillo Jimmy , Méndez-Estrada + Víctor Hugo , Brenes Prendas Steven 
Published: March 2017

: El establecimiento de compañías bananeras en Costa Rica trajo fuentes de empleo y mejoras infraestructura, pero también problemas sociales, destrucción de bosques, erosión del suelo y contaminación de ríos y quebradas. La erosión en bananales puede verse disminuida con prácticas de cobertura vegetal. Aquí analizamos el efecto de la planta arvense Geophila macropoda (oreja de ratón) en la erosión en Guápiles, Costa Rica. Elegimos tres clases de suelos I, II y III cubiertos con oreja de ratón y sin ella. Entre junio y agosto de 2012 se realizaron mediciones periódicas una vez por semana, abarcando periodos de baja, media y alta precipitación. Encontramos que la erosión aumenta con la precipitación y que en todos los suelos la cobertura de G. macropoda redujo la erosión.