bluuebunny/crossref_metadata_2025 huggingface dataset:
Situated mapping: visualizing urban inequality between the god trick and strategic positivism
Authors: Shelton Taylor
Published: February 2021

This paper asks, and seeks to answer, the question: what makes mapping critical? I argue that most examples of ‘doing’ critical mapping tend to fall into one of two camps with very different manifestations, goals and assumptions, whether from Donna Haraway’s invocation of – and desire to counteract – what she calls the “god trick”, or from the spirit of “strategic positivism” advocated by the geographer Elvin Wyly. The rest of the paper argues, however, that these two positions are not mutually exclusive, and that practitioners of critical mapping need not choose between the twin imperatives of destabilizing our understanding of the objectivity of cartographic knowledge and taking advantage of such a pervasive understanding in order to produce a more socially and spatially just world. Instead, I argue that it is possible to simultaneously use maps to prove that inequality exists, while also demonstrating that the ways we conventionally think about such inequalities through maps are insufficient to understand the complex realities of the processes that we are mapping. Using examples from my own research on mapping the relational geographies of vacant and abandoned properties in Louisville, Kentucky, I demonstrate one possible example of what such an approach to situated mapping might look like.
Two worlds of online labour markets: Exploring segmentation using finite mixture models and a network of skill co-occurrence
Authors: Lukac Martin
Published: February 2021

Technological innovations have enabled the emergence of online labour market platforms, empowering individuals to penetrate the world of traditional offshoring and challenging localised labour market dynamics. A great number of workers thrive at online platforms and embrace these tools to find customers for their businesses, to counterbalance market fluctuations, and earn wages above the local average. However, online labour market workers are also known to suffer numerous drawbacks, such as precarious working conditions, unpaid work, and severe fragmentation of jobs into tasks that limit skill use and development. Yet, our understanding of what causes this divergence in experiences is limited. Adopting propositions from the labour market segmentation literature, I show that, similarly to offline markets, online labour markets are composed of structurally delimited segments with different social processes governing the allocation of work. Using unsupervised clustering techniques from network science, I show that the clustered skill topology constrains mobility between segments in online platforms. I also show that this segmentation explains large differences in the earnings potential of individual workers. Together, these results provide a new explanation for the persistence of diversified experiences in online labour markets and inform strategies for future research of online platforms as highly segmented labour markets.
A Mechanistic Approach to Anti-nociceptive Potential of Nymphaea lotus Linn (Nymphaeaceae) in Rodents
Authors: Agbaje EO , Iwe A , Oguntokun OJ
Published: February 2021

Background: Nymphaea lotus Linn. (Nymphaeaceae), commonly known as white water-lily, white lotus or Egyptian lotus, is an important and well-known medicinal plant, widely used in the Ayurveda and Siddha systems of medicine for the treatment of diabetes, inflammation, liver disorders, urinary disorders, fever, skin diseases, cancer, gonorrhoea, pain and bronchitis. Objective: The study was designed to explore anti-nociceptive potential of aqueous extract of Nymphaea lotus leaf, its possible mechanism of action, and antioxidant properties. Methods: The anti-nociceptive activity of Nymphaea lotus (50, 100 and 250 mg/kg) was explored using writhing, formalin, tail clip and hot plate tests, while formalin test was used to investigate the involvement of opioid, dopamine, serotonin, K+ channel blocker, α1-adrenergic and α2- adrenergic systems. The antioxidant effect was carried out using DPPH, nitric oxide free radical scavenging activity and the reducing power effect. Total phenolic and flavonoids contents were also explored. Results: Oral administration of N. lotus in doses of 50, 100 and 250 mg/kg recorded a significant (p<0.05) dose dependent obstruction of nociception. A remarkable effect was recorded with the writhing and formalin tests and a significant effect was also observed in the tail clip and hot plate test, which suggests peripheral and central anti-nociceptive activity of the extract. The anti-nociceptive effect produced by N. lotus was significantly reversed by naloxone and yohimbine, suggesting the possible involvement of opioid and α2–adrenergic systems in its anti-nociceptive activity. N. lotus also displayed a potent antioxidant activity. Conclusion: These findings justify the folkloric use of N. lotus in pain management.
Evaluation of antioxidant and antidepressant activity of hydro-alcoholic extract of Ximenia americana stem bark
Authors: Togbossi Lucie A , Lawson-Evi Povi , Diallo Abdoulatif , Eklu-Gadegbeku Kwashie , Aklikokou Kodjo
Published: February 2021

The present study was undertaken to evaluate the antioxidant and antidepressant activity of hydroalcoholic extract of Ximenia americana in case of Sodium fluoride induced toxicity on ICR mices. Antioxidant activity of the plant was evaluated in vitro through 2,2’-Azobis (2-Amidino-propane) Dihydrochloride test, metal chelating assay and total antioxidant capacity and in vivo through evaluation of malondialdehyde content in brain and liver. Antidepressant activity was evaluated through tail suspension test. In vitro evaluation of antioxidant activity showed that hydro-alcoholic extract of stem bark of Ximenia americana possesses a total antioxidant capacity of 303.081 ± 4.946 mg equivalent ascorbic acid per gram. From 2, 2’-Azobis (2-Amidino-propane) Dihydrochloride and metal chelating tests, it emerged that the extract inhibits hemolysis and chelates metals concentration-dependent manner. Animals were randomly divided into four groups with five animals in each group. The control group received distilled water, group II received sodium fluoride at dose of 13.6 mg/kg body weight, group III and group VI: received respectively hydro-alcoholic extract of Ximenia americana at 250 mg/kg and 500 mg/kg with sodium fluoride during 7 days. Results showed sodium fluoride decrease animal’s body weight even at the presence of the extract, increased significantly animal’s inactivity time and malondialdehyde levels in liver and brain. Animal’s inactivity time and malondialdehyde levels were significantly improved at the presence of the hydro-alcoholic extract of Ximenia americana. Ximenia americana have potential to mitigate sodium fluoride toxicity.
In vitro anti-inflammatory activity of aqueous extract of Albizia lebbeck leaf (l.)
Authors: B Kamala Lakshmi , Valarmathi S
Published: February 2021

Albizia lebbeck (L.) Benth is an important traditional tree found throughout India. All part of this tree is considered as folk medicine and used for treatment of various disease. Current research work was carried out to identify the bioactive compound by phytochemical screening and to evaluate anti-inflammatory potential of aqueous leaf extract of A. lebbeck. The phytochemical screening of the leaf of A. lebbeck shows the presence of alkaloid, flavonoid, tannin, phenol, saponin, glycoside and free amino acid. The maximum inhibition of protein denaturation was found to be 78.06±0.5% at 500 µg/mL concentration and its IC₅₀ was 330 µg/mL concentration. The maximum inhibition in membrane stabilization was found to be 74.09±0.33% at 500 µg/mL concentration and its IC₅₀ was 440 µg/mL concentration. The maximum protection in hypotonicity induced haemolysis shows about 69.34±0.38% at 500 µg/mL concentration and its IC₅₀ was 400 µg/mL concentration. In vitro assay shows the moderate activity of anti-inflammatory in aqueous extract of A. lebbeck, when compared with the standard.
Botany, phytochemistry, pharmacology and Unani traditional uses of Jadwar (Delphinium denudatum Wall.): A Review
Authors: Aleem Mohd , Ahmad Ejaz , Anis Mohd
Published: February 2021

Delphinium denudatum Wall (DD), commonly known as Jadwar in India, is an essential plant of the Unani system of medicine. In Unani medicine, Jadwar is considered an antidote to poisons, refrigerant, nerve tonic, cardiotonic, demulcent, lithotriptic, diuretic, and antipyretic. It is beneficial in the treatment of fungal infections, paralysis, facial palsy, epilepsy, infantile convulsions, migraine, mania, hysteria, numbness, tremors, cholera, jaundice, cardiac diseases, arthritis, rheumatism, toothache, aconite poisoning, snake bite, scorpion sting and all kinds of pain. Many bioactive constituents are isolated from DD, including flavonoids, triterpenoids, alkaloids, including delphocurarine, staphisagrine, delphine, condelphine, denudatin, delnudine, delnuline, vilmorri anonymouse, vilmorrianone, a diterpenoid alkaloid. The scientific analysis of Jadwar demonstrates many of the activities mentioned in Unani literature. Nevertheless, further research is needed to identify the mechanism, active constituent, and usefulness of Jadwar in clinical practice. Given the encouraging results against neurological disorders in the prefaces, this aspect should be thoroughly investigated to make it a standard medicine.
Induced Spawning of Sahar, Tor putitora (Hamilton-Buchanan) in Terai Region of Nepal
Authors: Bista Jay D , Ranjan Rahul , Pandit Narayan P , Shrestha Madhav K , Diana James S
Published: February 2021

Sahar, Tor putitora (Hamilton-Buchanan) is a high valued indigenous riverine species of Nepal. This is declining in its natural habitat. Tor putitora and Tor tor (Hamilton-Buchanan) have been recommended as vulnerable and endangered species. Limited seed production using natural propagation has restricted its expansion in culture as well as rehabilitation in natural waters. The artificial propagation of sahar using synthetic hormone was conducted in Pokhara, AFU, Chitwan and CARP), Kathar during February to April 2017. Sixty five male (0.5-1.8 kg) and forty five female (1.1-2.1 kg) brood fish were reared in 200 m2 earthen ponds at 1000 kg/ha. Fish were fed with 32% crude protein feed at 3% body weight per day. Maturity was observed regularly for softness of the abdomen. Female brood fish with a soft and extended abdomen were injected with synthetic hormone (Ovaprim) at 0.5 ml/kg body weight. Males were not injected hormone. The fertilized eggs were incubated in Atkin hatching trays. A total of 16 females were induced to spawn, and they produced 1630.80±184.30 (mean±SE) eggs per kg body weight. Mean hatching and larval survival rates were 78.4±1.9 and 74.7±1.1%, respectively.
Survey on Carp Seed Production in Private Fish Hatcheries of Nepal
Authors: Jha Dilip K , Bhujel Ram C , Anal Anil K
Published: February 2021

Aquaculture is rapidly expanding in Nepal as a result demand for fish seed is increasing. Access to adequate high quality seed is the basis for sustainable aquaculture development. Due to quick and high profitability, and encouraging government policy, a number of private hatcheries are increasing especially in southern parts of the country. A survey of 40 private fish hatcheries was conducted from different regions (Eastern-9; Central-19, Western-6, Midwestern-3 and Farwestern-3) representing 15 districts (Morang, Sunsari, Saptari, Siraha, Dhanusha, Mahottari, Bara, Chitwan, Nawalparasi, Rupandehi, Kapilvastu, Banke, Bardiya, Kailali and Kanchanpur) of Terai and inner Terai to assess the status of different stages of seed production within five year from March 2009 to April 2014. The survey revealed that total production of hatchlings, fry and advanced fry within five years were 15852.6, 879.5 and 259.5 million respectively. All these development regions showed increasing trend of their own contribution within a total of five years. The percentage of eggs fertility and hatchability was more (78.3 and 71.7) in mid western development region followed by eastern (68.9 and 61.7), central (68.3 and 61.7), far western (68.3 and 61.7) and western (68.3 and 60.0). Though private hatcheries played important role in seed production, improving their efficiency are imperative, further studies are recommended to overcome constraints on carp seed production.
Temporal Changes of Water Quality Parameters in Rupa Lake and their Impact on Productivity
Authors: Husen Md. Akbal , Dhakal Ram P , Nepal Agni P
Published: February 2021

Knowledge on nutrient dynamics of the lake provide basis for modality and extent of exploitation of fishery resources. Therefore, a long-term data of physico-chemical parameters was analyzed for the assessment of changing aquatic environment and its impact on aquatic biodiversity. The physical and chemical properties of water have been changed over 14 years (1994 to 2007). Increase in mean annual concentrations of dissolved oxygen in recent years (2002 to 2007) were recorded in the lake, which indicate improvement in water quality due to lake restoration. Annual mean pH levels were not consistent to produce specific trends. The pH of the water increased from 1994 to 2002, and then decreased continuously in later period. Water transparency increased with the decreased chlorophyll 'a' concentration during 1999 to 2002 due to degraded condition. The higher concentrations (0.010- 0.017 mgl-1) of soluble reactive phosphorous (SRP- PO4) were recorded during 1994 to 2000, later SRP concentration (0.003-0.012 mgl-1) tend to reduce. Effect of fluctuation in the physico-chemical properties on the lake productivity in terms of fish yield was assessed.
Prevalence of Intestinal Parasites in Children of Bheerkot, Syangja, Nepal
Authors: Basaula Rajendra , Gurung Santosh
Published: February 2021

This study was carried out to determine the prevalence of intestinal parasitic infections among the children of age group 4-12 years in Bheerkot Municipality of Syangja District, Nepal, at an altitude of 1088 m above sea level. The research was conducted among 50 children i.e., 24.27% of total children population of that age group. Among 50, 21 (42%) and 29 (58%) were male and female respectively, on which parasitic infection was observed in 42.85% of male population and 31.03% of female population, but there was no association of gender for the infections of intestinal parasites. This indicates that the association of gender with intestinal parasitic infection differs from one community to other and might be attributed to socio-behavioral activities. The samples were examined under optical microscope (low power-10X and high power 40X). The major intestinal parasites detected were Giardia lamblia (Lambl), Entamoeaba histolytica (Schaudinn), Entamoeba coli (Grassi) and Trichuris trichiura (Linnaeus). In conclusion, among above mentioned parasites, Giardia lamblia was found with higher prevalence infecting 16 of total children, we recommend for improvement in the drinking water habit and proper sanitation in the people of Bheerkot-3 and need of effective social awareness programs
Induced Breeding of Grass Carp, Ctenopharyngodon idella (Valenciennes) in Rupandehi, Nepal
Authors: Jha Bidhya S , Neupane Sirsiya
Published: February 2021

Induced breeding is a scientific approach to the modern fish breeding procedure whereby ripen brood fishes are stimulated to release the eggs by pituitary hormone or any other synthetic hormone to breed in captive condition. Fish pituitary is mainly used for induced breeding but due to difficulties in the preparation of injections and preservation, nowdays synthetic hormones like LHRH-a, Ovaprim, WOVA-FH, Ovatide etc. are found to be used for induced breeding. A total of 4 sets of female grass carp were used for induced breeding with application of LHRH-a and pituitary extract in April at Mandal Fish Hatchery, Rupandehi. In total 23,67,500 eggs were collected and incubated. Fecundity, fertility and hatching rates were 1,25,000, 40-70% and 60-70% respectively. The rate of breeding especially, fertilization and hatching rate with LHRH-a was found better than with pituitary extracts.
Cinnamon Bittern, Ixobrychus cinnamomeus (Gmelin) from Annapurna Conservation Area, Nepal
Authors: Baral Rishi , Dahal Tulasi P , Thapa Suresh , Gurung Dhan K , Acharya Raju
Published: February 2021

No abstract available.
Validación de índices de cosecha para manzanas de bajos requerimientos de frío
Authors: Bouzo Carlos Alberto , Gariglio Norberto Francisco
Published: February 2021

El objetivo de este trabajo fue evaluar índices de cosecha en manzanos con bajos requerimientos de horas de frío. Se utilizaron frutos provenientes de tres variedades de manzanos procedentes de cruzamientos realizados por IAPAR (Instituto Agronómico do Paraná Brasil): ‘Eva’ (Anna x Gala); ‘Caricia’ (Anna x Prima) y ‘Princesa’ (Anna X NJ56). El experimento se realizó durante los años 2009 y 2010, y los frutos fueron cosechados en diferentes momentos iniciándose con tamaño final y color verde dominante. Se midieron las siguientes variables: (i) Índice de Almidón IA (adim.); (ii) Firmeza externa, F (N); y (iii) concentración de Sólidos Solubles Totales, SST (%). Se elaboró una carta de IA de tipo radial con el objeto de adaptar su uso para estas variedades de manzanos. Aunque el IA fue diferente para cada variedad con respecto al tiempo desde inicio de cosecha, resultó el método con menor variabilidad (R2 = 0,77) y mejor capacidad de predicción de la madurez de la fruta. Aunque las correlaciones efectuadas entre los índices de cosecha fueron bajas, resultaron mayores cuando se compararon IA y SST para las tres variedades. Se discuten la relación entre los tres índices y las posibles causas de la dispersión de los datos medidos.
Influencia del raleo sobre el módulo de elasticidad y ruptura en Eucalyptus grandis
Authors: Cueto Guillermo , O´Neill Hugo , Rachid Cecilia , Ohta Sadaaki , Resquin Fernando
Published: February 2021

El presente trabajo está enfocado en Eucalyptus grandis, principal especie del género plantada en Uruguay para obtener madera sólida. El objetivo del mismo es evaluar la incidencia de la intensidad del raleo sobre el módulo de elasticidad (MOE) y el módulo de rotura (MOR). El monte seleccionado se ubica en el departamento de Tacuarembó y fue plantado sobre suelo arenoso en el año 1989, con semilla proveniente de Bañando de Medina (Uruguay). El ensayo fue diseñado con parcelas al azar, con dos repeticiones y tres tratamientos: A) raleo fuerte con 272 árboles /ha remanentes, B) raleo medio con 352 árboles/ha remanentes y C) sin raleo, con 1280 árboles /ha. El raleo fue realizado en el año 1994, cuando el monte tenía cinco años y las evaluaciones se efectuaron cuanto el monte alcanzó los 19 años de edad. De cada tratamiento se seleccionaron los 10 individuos promedio de diámetro a la altura del pecho (DAP) para obtener las tablas y probetas libres de defecto a ensayar. Las variables analizadas fueron el MOE y el MOR de tablas con dimensiones comerciales y probetas libres de defectos. No se observaron diferencias significativas en las variables analizadas.
Control de Nosema ceranae en colonias de abejas (Apis mellifera) en forestaciones de Eucalyptus grandis
Authors: Mendoza Yamandú , Harriet Jorge , Campa Juan , Katz Helena , Ramallo Gustavo , Díaz-Cetti Sebastián , Invernizzi Ciro
Published: February 2021

La nosemosis es una enfermedad causada por los microsporidios Nosema Apis y Nosema ceranae que afecta las funciones digestivas de las abejas melíferas (Apis mellifera). N. ceranae fue descrito en A. mellifera en el año 2005 y ha sido asociado a una elevada mortandad de colonias en algunos países del hemisferio norte. En Uruguay N. ceranae está presente en todo el territorio, mientras que es muy difícil encontrar a N. apis. La nosemosis se presenta indefectiblemente en las colonias que se trasladan a las forestaciones de Eucalyptus grandis y puede ser la causa de las elevadas pérdidas registradas allí durante el invierno. En un apiario emplazado en una forestación de E. grandis se evaluó el efecto de dos dosis de fumagilina (400 y 200 mg/colonia) y del propóleos (3 g/colonia) sobre la infectación por N. ceranae y el desarrollo poblacional en primavera. Se encontró que las colonias que recibieron 400 mg de fumagilina resultaron menos infectadas por N. ceranae que las del grupo control (P<0,01), mientras que en las colonias que recibieron 200 mg de fumagilina la diferencia se dio con un nivel de significancia marginal (P=0,09). Las colonias que recibieron extracto de propóleos no se diferenciaron de las del grupo control en el nivel de nosemosis (P>0,10). En primavera las colonias que recibieron 400 mg de fumagilina presentaron una mayor población que las de los demás grupos (P<0,01). Este estudio muestra que la infectación por N. ceranae incide en la mortandad y tamaño de las colonias durante el invierno.
Desarrollo de un multiplex de microsatélites para diagnóstico de paternidad en ovinos Corriedale del Uruguay
Authors: Peraza Pablo , Rincón Gonzalo , Ravagnolo Olga , Dalla Rizza Marco , Kelly Lucy
Published: February 2021

En el Uruguay la raza Corriedale representa el 70% del stock ovino, por lo cual es importante garantizar la exactitud al realizar un diagnóstico de paternidades mediante tipificación de ADN, con el fin de asistir a los registros genealógicos y a los programas de selección para las características de importancia económica realizados en dicha raza. En el presente trabajo se desarrolló un multiplex de 10 microsatélites (Short Tandem Repeats, STR) recomendados del panel de la ISAG (International Society of Animal Genetics). Con este multiplex se analizó una población de 156 ovinos de la raza Corriedale del Uruguay. El objetivo del presente trabajo fue evaluar dicho multiplex de acuerdo a variabilidad genética de las frecuencias alélicas para la asignación de progenitores mediante los valores de su Probabilidad de Exclusión (PE). Los STR presentaron una variabilidad relativamente alta de acuerdo al Índice de Heterocigosidad promedio (HObs=0,661), al número de alelos observados (N=8,6) y al Contenido de Información Polimórfica (PIC=0,614). Se observó en cuatro de los 10 STR utilizados (FCB20, TGLA53, MCM527 y MCM130) una pérdida de equilibrio Hardy-Weinberg debido a la disminución significativa de heterocigotos, con la consiguiente reducción de variabilidad genética. Como consecuencia la Probabilidad de Exclusión combinada en dicha población presentó un valor de 0,960. Concluimos que para mejorar la certeza en el diagnóstico de paternidad se podría incluir un mayor número de STR en el multiplex, dada la baja variabilidad genética presente en los padres.
Exploración de alternativas para el desarrollo sostenible de sistemas de producción hortícola-ganaderos familiares en el sur de Uruguay
Authors: Aguerre Verónica , Chilibroste Pablo , Casagrande Marion , Dogliotti Santiago
Published: February 2021

La sostenibilidad de la mayoría de los predios hortícolas familiares en el sur de Uruguay está amenazada por ingresosinsuficientes y por el deterioro de los recursos naturales. En este estudio se cuantificó el efecto de la inclusión de diferentesactividades de producción ganadera en la estructura y en los resultados económico-productivos y ambientales de diferentestipos de sistemas de producción (predios) hortícolas. Se realizó un estudio exploratorio a escala predial con modelos desimulación utilizando dos predios como estudio de caso. Los resultados sugieren que la inclusión de actividades de producciónganadera en los sistemas de producción hortícolas es un factor determinante para reducir la erosión promedio del áreacultivada. Para reducir la erosión el modelo diseñó predios que reducen el área de hortalizas al tiempo que expanden larotación forrajera. Como consecuencia de esto, también se redujo el ingreso familiar (IF) entre 12 % y 31 % según el casoestudiado. Sin embargo, pudimos diseñar sistemas de producción con erosión menor a la tolerable para el tipo de suelo e IFmayor al objetivo, en los dos predios. De las actividades ganaderas evaluadas las más apropiadas para incluir en predios hortícolasson el engorde de novillos o vaquillonas en ciclos de 14 a 18 meses, debido al menor costo para reposición de animales y al menoruso de concentrados, lo que disminuye las necesidades de capital y la dependencia de insumos externos.
Propiedades físicas y mecánicas de la madera de una población de Eucalyptus bosistoana F. Muell. cultivada en Uruguay
Authors: Mantero Carlos , O’Neill Hugo , Cardoso Andrea , Castagna Andrés
Published: February 2021

Este trabajo tiene por objetivo la caracterización de la madera de Eucalyptus bosistoana, a través del estudio de las propiedades físicas (densidad y contracción) y mecánicas (flexión estática, dureza Janka y compresión paralela al grano).Se trabajó con 11 árboles de 42 años pertenecientes a una cortina forestal ubicada en la Estación Experimental Bernardo Rosengurtt (Bañado de Medina, Cerro Largo). Para la realización de los ensayos de densidad aparente, contracción, flexión estática y dureza Janka se siguió lo prescrito en las normas uruguayas, UNIT. Para el ensayo de compresión paralela se utilizó la norma norteamericana, ASTM. Se encontró que la densidad aparente básica de la especie es de 0,82 g cm-3 y la densidad aparente corriente es de 0,94 g cm-3. Se clasifica la madera como de alta contracción con un valor volumétrico de17,83 %. Respecto a las propiedades mecánicas con un contenido de humedad promedio de 15 %, la madera es de gran resistencia con valores de 66,19 MPa para la compresión paralela al grano y de 18738 MPa y de 146,2 MPa, MOE y MOR respectivamente, en flexión estática. Para estas propiedades se realizaron las correcciones al 12 % de contenido de humedad, utilizando factores de ajuste apropiados.
Diversidad vegetal del campo natural de Butia odorata (Barb. Rodr.) Noblick en Uruguay
Authors: Rivas Mercedes , Jaurena Martín , Gutiérrez Lucía , Barbieri Rosa Lía
Published: February 2021

Este trabajo fue realizado con el objetivo de caracterizar la diversidad vegetal del campo natural del palmar de Castillos (Rocha, Uruguay), identificar diferencias en la composición botánica dentro y fuera del palmar, determinar las especies que discriminan los dos ambientes y reconocer las potencialidades de los recursos genéticos y servicios ambientales. Mediante el uso del método de muestreo punto cuadrado, aplicado de dos formas (ocho transectas largas y 40 transectas cortas) se determinó la presencia de 70 taxones. Los representantes de la familia Poaceae son el 57,1 % de los taxones, mayoritariamente perennes, con una relación C4/C3 de 1,6. Los análisis de agrupamientos y de componentes principales mostraron diferencias consistentes en la composición florística del estrato herbáceo del campo con palmas y sin palmas. Estas diferencias se atribuyen a la adaptación de las especies a condiciones de sombreado y mayor humedad del suelo, entre las principales: Stenotaphrum secundatum, Pratia hederacea, Juncus spp., Hydrocotyle bonariensis, Paspalum urvillei, Paspalum proliferum y Plantago sp. El palmar provee de bienes de uso directo como forraje, sombra y abrigo para el ganado, producción de miel y recreación activa. Se reporta la utilización de un grupo destacado de recursos fitogenéticos de uso forrajero, medicinal y ornamental.
Nuevas curvas intensidad-duración-frecuencia de precipitación para el departamento de Montevideo, Uruguay
Authors: Silveira Luis , Usera Gabriel , Alonso Jimena , Scavone Martín , Chreties Christian , Perera Gonzalo , González Meliza
Published: February 2021

Las curvas intensidad-duración-frecuencia utilizadas en Uruguay se basan, según el autor, en información pluviográfica registrada entre 1906 y 1990. La disponibilidad de datos de las últimas décadas y la percepción generalizada que indica una tendencia creciente en la frecuencia de las precipitaciones intensas registradas en este último período, motivan la necesidad de actualizar las curvas intensidad-duración-frecuencia del Uruguay. La actualización hasta 2005 de la curva del Departamento de Montevideo no generó diferencias significativas. Los cuantiles de precipitación extrema para todas las duraciones no variaron en más de 5 % respecto de sus correspondientes de la serie histórica. No obstante, si se considera solamente el período 1981-2005, las curvas mostraron una disminución en los valores de intensidades máximas de precipitación de entre 10 y 20 % para períodos de retorno medio, excepto para eventos de corta duración, entre 1 hora hasta 20 minutos, en que se constató un aumento de igual magnitud al observado para las intensidades máximas correspondientes a períodos de retorno medios.
Evaluación social de tecnologías: algunas evidencias de impacto en la lechería uruguaya
Authors: Bianco Mariela
Published: February 2021

El impacto social de la tecnología se concibe como la influencia que los logros en ciencia y tecnología tienen en términos de beneficios económicos, sociales y/o culturales para una población. La evaluación de impacto social de tecnología agropecua-ria pretende identificar cambios en la satisfacción de necesidades básicas y/o en la calidad de vida. Su propósito es analizar cómo el uso de ciertas innovaciones contribuye al bienestar social de un establecimiento y las personas a él vinculadas. Un componente esencial para la evaluación social de tecnología es la opinión de los adoptantes en relación a los efectos de esta sobre distintos aspectos sociales. Este estudio exploró el impacto social de la tecnología utilizada en la lechería uruguaya en la última década a partir de una encuesta nacional a productores lecheros. Se buscó conocer la opinión de los productores acerca del efecto derivado de la adopción de tecnologías en un conjunto de variables de la dimensión social involucrando aspectos de capacitación y empleo, salud, ingreso gestión y administración. Se calcularon índices de impacto agregado que sintetizan la información de trece indicadores para cada tecnología evaluada. Todos los índices resultaron positivos sugiriendo que los impactos detectados por los productores en relación a los cambios tecnológicos efectuados se orientan, en general, a mejorar el conjunto de las variables sociales consideradas. No obstante, la intensidad de todos ellos es extremadamente baja y próxima al valor cero que representa la opinión neutra en relación a los efectos de la tecnología.
Cuantificación del riesgo de daños ocasionados por heladas tardías en Rafaela (Santa Fe, Argentina)
Authors: García Maria Soledad , Leva Perla , Maio Silvina , Tóffoli Guillermo , Gariglio Norberto
Published: February 2021

En la región centro de la provincia de Santa Fe, Argentina, se cultivan frutales de bajos requerimientos de frío. Una de las principales limitantes que afectan la producción de duraznero y otros frutales caducifolios es la ocurrencia de temperaturas mínimas críticas durante la floración y cuajado de frutos. La probabilidad de ocurrencia de daños por esta causa se evaluó mediante el índice de peligrosidad de heladas (IPH) el cual tiene en cuenta la fenología del cultivo y la probabilidad de ocurrencia de temperaturas críticas durante los distintos subperíodos del ciclo. En la localidad de Rafaela para el período 1970-2006, el valor de IPH obtenido fue de 71 %. Considerando la fenología de los durazneros cv. Flordaking, el riesgo de daño medio fue de un año en 1,4 (riesgo moderado). Estos resultados indican la conveniencia de usar medidas de protección contra heladas tardías.
Productividad y costos del raleo de algarrobo blanco (Prosopis alba) en Santiago del Estero, Argentina: Una primera aproximación
Authors: Coronel de Renolfi Marta , Cardona Gabriela , Moglia Juana G. , Gómez Adriana T.
Published: February 2021

Se analizó la operación de raleo forestal en dos plantaciones experimentales de algarrobo blanco (Prosopis alba) en la zona de riego de la provincia de Santiago del Estero, Argentina, mediante un estudio de tiempos y movimientos para conocer la productividad operacional y los costos asociados al proceso de apeo con motosierra. Se midieron tiempos efectivos y operativos y se calculó volumen con corteza, eficiencia, productividad y costo directo del raleo. La muestra de 83 árboles completó un volumen abatido de 5,66 m3 . El tiempo operativo promedio fue de 2,66 min/árbol, mientras que el tiempo efectivo medio fue de 1,36 min/árbol. Se halló gran variabilidad dimensional en los árboles de la muestra y un elevado grado de variabilidad en los tiempos de trabajo. Se verificó una fuerte correlación entre el tiempo efectivo de trabajo de la máquina y las variables diámetro y volumen de los árboles. La eficiencia operacional fue del 51 %. La productividad en el derribo fue de 1,54 m3 /h (22,56 árboles/h). El costo unitario del raleo fue de 12,18 US$/m3 , equivalente a 64,56 $/m3 (1 US$ = 5,30 $ en mayo 2013). Los resultados para eficiencia, productividad y costo del raleo son preliminares y constituyen el primer antecedente en la zona.
Estrategias empresariales en el complejo lácteo del Litoral Norte
Authors: Piedrabuena Laura , Arbeletche Pedro
Published: February 2021

Uruguay cuenta con una importante y larga experiencia en la producción y procesamiento de leche con destino al mercado local y la exportación. Esta cadena agroalimentaria ha permitido un gran desarrollo de las capacidades de producción, tanto en la fase primaria como en la industrial, así como en la comercialización de sus productos. La fase agraria de la lechería se desarrolla principalmente en dos cuencas, la Cuenca Sur y el Litoral Norte. Esta investigación tiene por objetivo contribuir al análisis de las estrategias empresariales de las industrias lácteas del Litoral Norte, y su impacto sobre el complejo agroindustrial, fundamentalmente la etapa primaria, a partir de la identificación de relaciones técnicas, económicas, y financieras. Mediante la triangulación de técnicas cuanti y cualitativas fue posible comprender con mayor profundidad las relaciones de dominación a la interna del complejo. Si bien las tres industrias presentan similitudes en cuanto a tamaño y número de productores, con plantas muy próximas entre sí, muestran importantes diferencias en su base agraria, y en sus estrategias verticales bajo los tres tipos de fuentes, lo cual justifica su estudio comparativo. Las estructuras de propiedad del capital no necesariamente van de la mano con las formas de ejercer el poder dentro del complejo, existen otros factores que inciden sobre su accionar y determinan su dinámica.
DISTRIBUTION OF MERCURY IN COAL SEAMS (ON THE EXAMPLE OF THE KRASNOARMEISKIY GEOLOGICAL AND INDUSTRIAL REGION OF DONBASS)
Authors:   Donetsk National Technical University, Pashchenko Pavlo , Antipovych Yana , Karamushka Olga
Published: February 2021

Purpose. Analysis of the distribution of mercury concentrations in the whole district; identification of links between mercury content and other toxic and potentially toxic elements, petrographic composition of coal and its main technological parameters. Methodology. The methods of mathematical statistics with the construction of histograms of distribution and dendrograms of clustering of coal seams of the region by Hg concentrations are also used in the work. Results. Peculiarities of distribution and the nature of mercury distribution in 56 coal seams, which belong to the suites С14, С21, С22, С23, С25, С26, and С27 of the lower and middle divisions of the coal period of the Krasnoarmeysk geologicalindustrial area, have been determined. Simple and cumulative histograms are constructed and analyzed. The calculations of the weighted average concentrations in the coal of the main layers and suites were performed, the composition of the typomorphic geochemical association of mercury with other toxic and potentially toxic elements in the coal of the region is clarified. The main factors influencing the mercury content in the nearest stratigraphic section of coal seams in the process of coal accumulation and epigenetic transformations of the coal seam were significantly varied. The average value of mercury content in coal of the main working seams of the area is significantly below the maximum allowable concentration in coal. In the district as a whole, there is no significant connection between mercury concentrations and ash content and sulfur content of total coal, at the same time there is an increase in mercury content with increasing degree of coal carbonization. Scientific novelty. The nature of the distribution and the main statistical indicators of mercury concentrations in the main coal seams and suites of the Krasnoarmeysky geological-industrial region of Donbass were established. A typomorphic geochemical association of mercury with other toxic and potentially toxic elements in the coal seams of the district has been established. Practical significance. The practical significance of the obtained results is to identify the absence of a significant relationship between mercury concentrations and ash content and sulfur content of total coal, as well as to calculate the regression equations between the elements included in the geochemical association with mercury. Key words: mercury, mine, coal height, coal ash content, depth, sulfur content, regression equation, correlation coefficient.
DISTRIBUTION OF MERCURY IN COAL SEAM C7н OF PAVLOHRADSKA MINE FIELD
Authors:   Donetsk National Technical University, Ishkov Valerii , Kozii Yevhen
Published: February 2021

Purpose. Investigation of regularities of mercury distribution in coal of formation c7n of the Pavlogradska mine field. Methodology. Method of atomic absorption analysis of furrow samples of wells. Processing of geochemical and structural-geological data by methods of mathematical statistics using Excel 2016 and Statistica 6.0. The computer program Surfer was used to build maps/ Results. In article considered the distribution of mercury in the coal seam c7н of the Pavlohradska mine field of the Pavlohrad-Petropavlivka geological and industrial district of Donbas. As a result of the study, a map of isoconcentrates and a map of the regional component of mercury content in the coal of the seam were constructed and analyzed. Correlation coefficients between mercury concentration and formation morphological parameters and coal sulfur were calculated. The regression equations between this element and the ash content of coal are also established, which will allow predicting their concentration in the main working coal seams of the geological-industrial area relative to the values of coal ash content. The nature of sulfur distribution is established and the weighted average concentrations and the main descriptive statistics of this element are calculated. Scientific novelty. Peculiarities and regularities of mercury accumulation in coal of formation c7n are revealed. Practical significance. The constructed maps and established correlations are the factual basis for long-term forecasting of mercury concentrations in extracted raw materials and adjustment of technological schemes of coal beneficiation. Keywords: mercury, mine, coal height, ash content, stratum depth, sulfur content, regression equation, correlation coefficient.
INFLUENCE OF PLASTIC DEFORMATION ON THE PHYSICAL PROPERTIES OF GRANULAR QUARTZ
Authors:   Donetsk National Technical University, Polyashov Alexander , Zaporozhets Andrey , Nazarov Ivan
Published: February 2021

Purpose. To study traces of plastic deformation in quartz of crystalline rocks of the Sea of Azov. Methodology. Work was done in the field to observe the crystallinity of the crystalline rocks of the Sea of ​​Azov. In laboratory conditions, samples were made from samples taken of rocks and quartz, in which traces of plastic deformation were observed qualitatively by visual and optical methods by transmission and reflection. In natural and ultraviolet light, the physical properties of quartz were quantified, and the effects of luminescence in quartz samples and quartz sandstone material were studied and analyzed. Results. The forms of manifestation of quartzity in crystalline rocks of the Azov Sea were studied, geological bodies composed of quartz were tested, samples were taken from samples taken to observe traces of plastic deformation. The fact of luminescence of granular quartz was established, in which traces of plastic deformation act as luminescence centers. The luminescence of Donbass Carboniferous sandstones is shown, in which quartz grains, which bear traces of plastic deformations, serve as luminescence centers. Scientific novelty. A scientific fact has been established that traces of plastic deformation serve as centers of luminescence of quartz. Practical significance. The established effect of the relationship between quartz luminescence and traces of plastic deformation can be used in the field as a diagnostic sign of plastic deformation of quartz and in mine ones for qualitative control of the impact hazard of Donbass sandstones. Keywords: quartz content, granular quartz, luminescence, luminescence center, traces of plastic deformation, impact hazard of sandstones.
UNIVERSAL METRIC BASE (RUMB), UNITS OF ANGLE MEASUREMENT IN GEODESY AND CARTOGRAPHY
Authors:   Donetsk National Technical University, Ryazantsev Nikola , Nosach Alexander
Published: February 2021

Objective. Study of ancient cartographic documents in order to clarify the principle of working with a portolan map based on the RUMB metric base. Methodology. Analytical, graphic, mathematical, geodesic. Scientific novelty. For the first time, a table of interrelation of units of measurement of time, angles and distances in the metric base of RUMB is shown. It was found that the so-called portolan maps were built on the basis of RUMB, and their projection is similar to the oblique Mercator projection with a cylindrical axis oriented along the earth’s magnetic axis, with an additional network of rhomb rectangular coordinates, which allows the map to be used at any position of the poles. The Mercator projection is a simplified version of it with one coordinate system. Practical implications. It is shown that dividing the clock face, equator and meridians of the Earth into the same number of parts allows determining the coordinates of points on the Earth’s surface using any of the known parameters, which greatly simplifies the solution of geodetic and navigation problems. Key words: units of measurement, metric base, degree, bearing, portolan map, rose card, projection, coordinate.
Editorial
Authors: Magonet Jonathan
Published: February 2021

The major part of this issue is taken up by four articles organised by Cornelia Wilhelm on the theme of ‘The Synagogue and the Legacies of the Holocaust: The German Refugee Rabbis and Cantors’. It is a continuation of Professor Wilhelm’s research on the fate of refugee rabbis who escaped from Nazi Germany. The topic was previously considered in our issue (Volume 45, No. 2, September 2012) which published the proceedings of a conference organised by Professor Wilhelm and Tobias Grill in Tutzing on 1 October 2009 on ‘German Rabbis Abroad’. Here, Professor Wilhelm introduces the four articles and provides an overview of the topics covered.
Starting Anew
Authors: Zajdband Astrid
Published: February 2021

In the aftermath of the November pogrom of 1938, thirty thousand Jewish men were arrested and sent to concentration camps. After being released, around one hundred rabbis were able to leave Germany for Great Britain. But escaping Germany was not the end of their personal hardship. Once respected community leaders, rabbis arrived destitute and depended on charitable organisations for their livelihoods. Some would be classified as enemy aliens and faced with internment once again. The refugee rabbis would not to be discouraged, however, and they began, at first just a small circle, to reclaim their place in Jewish life once again. In a new country, a new context, and in the midst of around eighty thousand refugees, the rabbis were able to reignite their work and embarked on a great number of initiatives and projects. They were able to place the German Jewish heritage into Anglo-Jewry, where it continues to live on today.
Влияние направления прозвучивания и собственной частоты преобразователей при испытании динасовых кирпичей ультразвуковым импульсным методом
Authors: Брожовский Иржи , Боднарова Ленка
Published: February 2021

Evaluating the quality of refractory materials is one of the important stages of production before these materials are handed over to the customer. One of the required parameters is to evaluate ultrasonic pulse velocity, as determined by measurements performed via the ultrasonic pulse method. Are presents findings on the influence of the direction of transmission and the natural frequency of transducers on ultrasonic pulse method measurements of silica refractory bricks. The findings reveal that the measurement requirements specified in standards for other building materials cannot be fully applied in the case of silica refractory bricks, and the assumption that ultrasonic pulse velocity increases with shorter measuring bases is not confirmed. The highest ultrasonic pulse velocities were measured during transmission across the width of the product, while the lowest velocities were measured over the thickness of the sample. In order to evaluate the quality of silica refractory bricks, it is necessary to unambiguously determine a uniform measuring base for transmission so as to ensure the reproducibility of the measurements performed by different laboratories.
Диагностика ударных повреждений монолитных и сотовых углепластиков с помощью ультразвуковых волн Лэмба
Authors: Бурков М.В. , Еремин А.В. , Бяков А.В. , Любутин П.С. , Панин С.В.
Published: February 2021

The paper presents the results on Lamb waves based technique for impact damage detection and severity identification. The PZT network operates in the round-robin mode changing the actuator and sensor roles of the transducers in order to detect the response of the system in the presence of damage. The monitoring is performed via the analysis of three parameters: change of the amplitude (dA), change of the energy (dP) and cross-correlation (NCC) of the signals in baseline and damaged state. Testing of laminate CFRPs shows that the damage location is estimated within the 5–15 mm error, while the computed Damage index linearly is dependent on the applied impact energy. For honeycomb CFRPs the NCC parameter do not provide accurate results, however, the other parameters allow identification within the 5–20 mm error and reflect accurate data on the severity of the damage.