Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya

Cleal, C.J., Bhat, G.M., Singh, K.J., Dar, A.M., Saxena, A. & Chandra, S., February 2016. Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

The Sepukhovian fossil floras of the northern margins of Gondwana, on the shores of the Palaeotethys, are dominated by remains of an eligulate, mainly monopodial lycopsid with persistent leaves. The stems show considerable morphological and preservational variation that has historically resulted in the fossils having been assigned to many fossil-species and -genera. However, there is now clear evidence that this simply reflects variation within a single fossil-species, reflecting biological variation and the effects of variable taphonomy, for which the correct taxonomic name is Spondylodendron pranabii (Pal) comb. nov. Part of this morphological variation might have been due to variations in growth rate during the life of the individual plants, which in turn might reflect stressed growing conditions in a wetland habitat. The systematic position of Spondylodendron remains uncertain, owing to the lack of unequivocal evidence of reproductive structures, but it might have affinities with the Sublepidodendraceae.

Christopher J. Cleal [chris.cleal@museumwales.ac.uk], Department of Natural Sciences, National Museum Wales, Cathays Park, Cardiff CF10 3NP, UK; G.M. Bhat [bhatgm@jugaa.com] and A.M. Dar, Department of Geology, University of Jammu, Jammu, India; Kamal Jeet Singh, [kamaljeet31@hotmail.com] and Anju Saxena [anju_saxena2002@yahoo.co.in], Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, (U.P.) India; Shaila Chandra, Flat Number 105, Beverly Park Apartment 422, New Hyderabad, Lucknow-226007, (U.P.) India.     

Gender earnings and poverty reduction: post-Communist Uzbekistan

Women get less of the material resources, social status, power and opportunities for self-actualization than men do who share their social location – be it a location based on class, race, occupation, ethnicity, religion, education, nationality, or any intersection of these factors. The process of feminization of poverty in Central Asia and Uzbekistan is intimately connected to the cultural and institutional limitations that put a ceiling on women’s involvement in economic activity. This article attempts to study and explore gender in the context of poverty reduction in Uzbekistan, the most populated state of Central Asia, to understand the ways and manner in which poverty and other forms of deprivation demand women’s participation in variety of contexts. The study is primarily an empirical one and is based on an extensive sociological investigation in the field.     

Incorporating Spatial Dynamics and Temporal Dependency in Land Use Change Models

This article formulates an empirical discrete land use model within a spatially explicit economic structural framework for land use change decisions. The underlying framework goes beyond mechanistically fitting models for the spatial process of land use change to more closely link landowner decision behavior to land use patterns. At the same time, the article explicitly considers spatial spillover effects in the decisions of landowners of proximately located parcels. These spillover or peer influences may be due to strategic or collaborative partnerships between landowners, and can be associated with variables observable to the analyst (such as accessibility to city centers and market places) and variables unobservable to the analyst (such as perhaps soil quality and neighborhood attitudes/politics). In addition to spatial spillover effects, heterogeneity is also likely to exist in the decision‐making process of different landowners because of differential responsiveness to various signals relevant to decision making. This leads to correlation in land uses across time that is stationary for the same spatial unit. The article accommodates these technical considerations by formulating a random coefficients spatial lag discrete choice model using a fine resolution for the spatial unit of analysis. Time‐varying random effects are also considered to capture the effects of time‐varying unobserved factors (for instance, unobserved landowner attitudes regarding specific land uses may shift over time). The model is estimated using Bhat's maximum approximate composite marginal likelihood inference approach. The analysis is undertaken using the City of Austin parcel‐level land use database for multiple years (1995, 2000, 2003, and 2006). The estimation results indicate that proximity to highways and other roadways, distance from floodplains, parcel location in the context of existing development, and distance from schools are important determinants of land use. As importantly, the results provide very strong evidence of temporal dependency and spatial dynamics in land use decisions. There is also a suggestion that major highways may not only physically partition regions, but may also act as social barriers for didactic interactions among individuals. Este artículo presenta un modelo empírico discreto de uso de tierra dentro de un marco económico estructural espacialmente explícito para la toma de decisiones de cambio de uso de suelo. El marco utilizado por los autores va más allá del ajuste mecánico de modelos al proceso espacial de cambio de uso de suelo pues vincula más estrechamente el comportamiento y decisión del terrateniente a los patrones de uso observados. Al mismo tiempo, el estudio considera explícitamente los efectos espaciales de difusión en las decisiones de los propietarios de las parcelas cercanas. Esta difusión (spillover) o influencia de los pares puede deberse a alianzas estratégicas o de colaboración entre los terratenientes. También pueden estar asociadodos a variables observables (como la accesibilidad a los centros de las ciudades y plazas de mercado), así como a las variables no observables (por ejemplo, la calidad del suelo y las actitudes o tendencias políticas de los residentes). Además de los efectos de spillover, también es probable que exista heterogeneidad en el proceso de toma de decisiones de los diversos terratenientes, debido a su diferente capacidad de respuesta a las distintas señales que influencian la toma de decisiones. Esto conduce a que exista correlación en los usos del suelo a través del tiempo que es estacionaria para la misma unidad espacial. En el estudio todas las consideraciones técnicas mencionadas son tomadas en cuenta mediante la formulación de un modelo de elección discreta con rezago espacial con coeficientes aleatorios (random coefficients spatial lag discrete choice model) usando unidades espaciales de alta resolución. Para capturar los efectos de los factores no observados que varían temporalmente los autores utilizan efectos aleatorios (random effects) (por ejemplo, las actitudes de los terratenientes con respecto a usos específicos de tierras pueden cambiar con el tiempo). El modelo propuesto es estimado utilizando el enfoque inferencial de similitudes marginales de aproximaciones máximas compuestas de Bhat (2011) (maximum approximate composite marginal likelihood ‐MACML). El análisis se lleva a cabo usando una base de datos de a nivel de parcela base de uso de la tierra de la ciudad de Austin, Texas para varios años (1995, 2000, 2003 y 2006). Los resultados de la estimación indican que la proximidad a las autopistas y otras carreteras, la distancia de las llanuras de inundación, la ubicación de parcela en el contexto del desarrollo urbano existente, y la distancia a las escuelas, son factores importantes para el uso de suelo. Adicionalmente, los resultados proporcionan evidencia muy clara de la dependencia temporal y la dinámica espacial en las decisiones de uso de suelo. El estudio también sugiere que las carreteras principales dividen las regiones no sólo físicamente, sino que también pueden actuar como barreras sociales para las interacciones entre los individuos. 本文提出了土地利用变化决策下空间经济结构框架的一种经验离散土地利用模型。土地利用变化的空间过程与土地所有者决策行为更为紧密连接的土地利用模式,使得潜在的框架超出已有拟合模型。同时,本文明确认为毗邻地块区位在地主决策中具有空间溢出效应。这种溢出或对等效应可能源于与地主有战略上或合作伙伴的关系,并且这种效应分为分析中可测的变量关联（如城市中心和市场区的可达性）和不可测的变量关联（如可能为土地质量和邻居态度/政策）两种。除空间溢出效应,异质性也可能存在于不同地主决策制定的过程中,因为多种信号的不同响应与决策制定相关。这种异质性导致了土地利用在相同空间单元时间演化过程中的相关性是平稳的。本文在理解这些含义的基础上对此采纳的技术考虑是,通过利用随机高分辨率的空间滞后离散选择模型来分析空间单元。随时间变化的随机效应也被考虑用来捕获不可测的时变因子效应（如不可测的关于特殊土地利用的地主态度可能随时间改变）。本文的模型通过Bhat’s（2011）提出的近似最大联合边缘似然推断方法（MACML）进行估计。分析数据来源于奥斯汀市土地利用关于地块尺度多年的数据库（1995,2000,2003,2006）。估计结果表明,与高速公路和其它道路的近邻性,与洪泛平原的距离,现状开发条件下的地块区位,以及跟学校的距离对于土地利用模式的确定是非常重要的决定因素。同样重要的是,该结果为空间动力学与时间依赖性的土地利用决策提供了非常强的证据。本结果也显示主要高速公路不仅是区域分割的物质表征,而且在个体之间的交流中扮演着社会障碍的角色。     

ESR response in tooth enamel to high-resolution CT scanning

High-resolution CT scanning of teeth with a resolution on the 20 to 30 μm scale introduces doses in the range of 250 to 420 Gy in the tooth enamel. If the induced doses cannot be precisely estimated, subsequent ESR dating analysis becomes impossible. Considering the increased availability of portable, high-resolution CT scanners, curators of valuable human dental fossils have to make an informed decision whether they want to preclude ESR analysis, one of the few dating methods that can be applied to older fossils.