Mammal endemism In Italy: A review

Although there are various checklists of Italian mammals, there is not yet a synthesis of those mammals that are endemic to Italy. Therefore, we provide for the first time a detailed review on Italian mammal endemic species including endemic taxa deserving additional studies. This review is based on the most recent taxonomic revisions obtained using Scopus and Google Scholar databases. We also considered the age of endemic species. Some aspects of mammalian conservation are also provided and discussed

Parametric study of thermal behavior of thrust chamber cooling channels

A numerical investigation is adopted for two dimensional thermal analysis of rocket thrust chamber wall (RL10), employing finite difference model with iterative scheme (implemented under relaxation factor of 0.9 for convergence) to compute temperature distribution within thrust chamber wall (which is composed of Nickel and Copper layers). The analysis is conducted for different boundary conditions: only convection boundary conditions then combined radiation, convection boundary conditions also for different aspect ratio (AR) of cooling channel. The results show that Utilizing cooling channels of high aspect ratio leads to decrease in temperature variation across thrust chamber wall, while no effects on heat transferred to the coolant is indicated. The radiation has a considerable effect on the computed wall temperature values

Quantifying whether different demographic models produce incongruent results on population dynamics of two long-term studied rodent species

1. Population density (ind/ha) of long-term (>15 years) series of CMR populations, using distinct demographic models designed for both open and closed populations, were analysed for two sympatric species of rodents (Myodes glareolus and Apodemus flavicollis) from a mountain area in central Italy, in order to test the relative performance of various employed demographic models. In particular, the hypothesis that enumeration models systematically underestimate the population size of a given population was tested.2. Overall, we compared the performance of 7 distinct demographic models, including both closed and open models, for each study species. Although the two species revealed remarkable intrinsic differences in demography traits (for instance, a lower propensity for being recaptured in Apodemus flavicollis), the Robust Design appeared to be the best fitting model, showing that it is the most suitable model for long-term studies.3. Among the various analysed demographic models, Jolly-Seber returned the lower estimates of population density for both species. Thus, this demographic model could not be suggested for being applied for long-term studies of small mammal populations because it tends to remarkably underestimate the effective population size. Nonetheless, yearly estimates of population density by Jolly-Seber correlated positively with yearly estimates of population density by closed population models, thus showing that interannual trends in population dynamics  were uncovered by both types of demographic models, although with different values in terms of true population size

Upper body balance control strategy during continuous 3D postural perturbation in young adults

We explored how changes in vision and perturbation frequency impacted upright postural control in healthy adults exposed to continuous multiaxial support-surface perturbation. Ten subjects were asked to maintain equilibrium in standing stance with eyes open (EO) and eyes closed (EC) during sinusoidal 3D rotations at 0.25 (L) and 0.50 Hz (H). We measured upper-body kinematics – head, trunk, and pelvis – and analyzed differences in horizontal displacements and roll, pitch, and yaw sways. The presence of vision significantly decreased upper-body displacements in the horizontal plane, especially at the head level, while in EC the head was the most unstable segment. H trials produced a greater segment stabilization compared to L ones in EO and EC. Analysis of sways showed that in EO participants stabilized their posture by reducing the variability of trunk angles; in H trials a sway decrease for the examined segments was observed in the yaw plane and, for the pelvis only, in the pitch plane. Our results suggest that, during continuous multiaxial perturbations, visual information induced: (i) in L condition, a continuous reconfiguration of multi-body-segments orientation to follow the perturbation; (ii) in H condition, a compensation for the ongoing perturbation. These findings were not confirmed in EC where the same strategy – that is, the use of the pelvis as a reference frame for the body balance was adopted both in L and H

A higher-taxon approach to rodent conservation priorities for the 21st century

Although rodents are not considered among the most threatened mammals, there is ample historical evidence concerning the vulnerability to extinction of several rodent phylogenetic lineages. Owing to the high number of species, poor taxonomy and the lack of detailed information on population status, the assessment of threat status according to IUCN criteria has still to be considered arbitrary in some cases. Public appreciation is scarce and tends to overlook the ecological role and conservation problems of an order representing about 41 percent of mammalian species. We provide an overview of the most relevant information concerning the conservation status of rodents at the genus, subfamily, and family level. For species¿poor taxa, the importance of distinct populations is highlighted and a splitter approach in taxonomy is adopted. Considering present constraints, strategies for the conservation of rodent diversity must rely mainly on higher taxon and hot-spot approaches. A clear understanding of phyletic relationships among difficult groups -such as Rattus, for instance- is an urgent goal. Even if rodent taxonomy is still unstable, high taxon approach is amply justified from a conservation standpoint as it offers a more subtle overview of the world terrestrial biodiversity than that offered by large mammals. Of the circa 451 living rodent genera, 126 (27,9 %), representing 168 living species, deserve conservation attention according to the present study. About 76 % of genera at risk are monotypic, confirming the danger of losing a considerable amount of phylogenetic distinctiveness

Aproximación a nivel de suprataxón de las prioridades de conservación de roedores en el siglo XXI

Although rodents are not considered among the most threatened mammals, there is ample historical evidence concerning the vulnerability to extinction of several rodent phylogenetic lineages. Owing to the high number of species, poor taxonomy and the lack of detailed information on population status, the assessment of threat status according to IUCN criteria has still to be considered arbitrary in some cases. Public appreciation is scarce and tends to overlook the ecological role and conservation problems of an order representing about 41 percent of mammalian species. We provide an overview of the most relevant information concerning the conservation status of rodents at the genus, subfamily, and family level. For species–poor taxa, the importance of distinct populations is highlighted and a splitter approach in taxonomy is adopted. Considering present constraints, strategies for the conservation of rodent diversity must rely mainly on higher taxon and hot–spot approaches. A clear understanding of phyletic relationships among difficult groups —such as Rattus, for instance— is an urgent goal. Even if rodent taxonomy is still unstable, high taxon approach is amply justified from a conservation standpoint as it offers a more subtle overview of the world terrestrial biodiversity than that offered by large mammals. Of the circa 451 living rodent genera, 126 (27,9 %), representing 168 living species, deserve conservation attention according to the present study. About 76 % of genera at risk are monotypic, confirming the danger of losing a considerable amount of phylogenetic distinctiveness.Aunque los roedores no figuren entre los mamíferos con mayor amenaza de extinción, existen pruebas históricas que demuestran la vulnerabilidad de diversos linajes filogenéticos de roedores. Debido al gran número de especies existentes, la taxonomía deficiente y la falta de información detallada sobre el estado de las poblaciones, en determinados casos es arbitrario determinar hasta qué punto algunas especies se encuentran en peligro de extinción de acuerdo con los criterios de la UICN. Además, si a ello se une el escaso aprecio que el público en general siente por los roedores, la situación explica que se pase por alto tanto el papel ecológico como los problemas de conservación de un orden al que pertenecen aproximadamente el 40% de todas las especies de mamíferos. Se proporciona información exhaustiva y relevante sobre el estado de conservación de los roedores, a nivel de género, familia y subfamilia. Para aquellas especies cuya taxonomía sigue estando incompleta, se destaca la importancia de las distintas poblaciones y su taxonomía se analiza por separado. A causa de las limitaciones actuales, las diferentes estrategias para la conservación de la diversidad de roedores deben basarse fundamentalmente en un mayor análisis del taxón y de los lugares de mayor concentración de poblaciones. Asimismo, una clara comprensión de las relaciones filéticas entre grupos difíciles (como por ejemplo Rattus) constituye un objetivo apremiante. Pese a que la taxonomía de los roedores no sea aún definitiva, desde un punto de vista conservacionista sigue siendo absolutamente justificable analizar el taxón con mayor detenimiento, ya que ofrece una visión general más precisa de la biodiversidad en zonas continentales que la que ofrecen los grandes mamíferos. De los aproximadamente 451 géneros de roedores existentes, 126 (el 27,9 %), que engloban a 168 especies, merecen una especial atención conservacionista según los datos de este estudio. Entre los géneros que se encuentran en peligro de extinción, un 76 % son monotípicos, lo que confirma el peligro de perder una cantidad considerable de singularidades filogenéticas

Assessment of Public Perspectives on Quality Control Measures in Public Water Supply in Oyo state, Nigeria

The study determined whether there were differences in public evaluation and perception of quality control measures adopted by a public water agency in Oyo State, Nigeria on the basis of some socio-demographic factors such as age, gender, marital status and socio-economic background. It used a sample of 350 respondents (187 males and 163 females) spread across four local government areas in Oyo State. The  major instrument used was a questionnaire while data analysis employed frequency counts and t-test statistics. Result showed that there were no significant differences in public perception of quality control measures adopted by the public water agency on the basis of the aforementioned factors. The result raises some fundamental issues that are connected with the quality of water supplied for public uses. It underscored the need to enhance a high quality in public water supply. The paper further went to proffer solutions on how to sustain safe water supplyin Nigerian cities: @ JASE

An investigation of shell-helical coiled tube heat exchanger used for solar water heating system

An experimental and theoretical study has been performed of thermal and hydrodynamic characteristics of a new type shell-helical coiled tube heat exchanger used as a storage tank in a closed loop solar water heater system for no water withdrawn from storage tank. The parameters studied are collectors heat gain, heat rejected from coils to shell side of the storage tank, average temperature of storage tank, friction factor, pressure drop, heat exchanger effectiveness, and collector efficiency for circulating mass flow rates of (1.8, 3, 6, 9 l/min), with no water consumption during a clear days in Baghdad. A FORTRAN 95 computer program was developed to evaluate theoretically the pressure drop across the helical coil and to process the experimental data. The results show that heat transfer inside helical coiled tubes is increased with increasing the circulation flow rates and coil diameter ratio. A transition from laminar to turbulent flow has been noticed at (6 and 9 l/min) circulation flow rates. For circulation flow rate of (6 l/min) the transition from laminar to turbulent flow is faster indicated for the outer coil than that for central coil, while the flow is laminar for inner coil. For (9 l/min) circulation flow rate the transition from laminar to turbulent has been noticed for all coils. Collector efficiency is increased with increasing circulation flow rates. The pressure drop decreases with the increase of solar radiation. Friction factor decreases with increasing circulation flow rate. The shell-triple concentric helical coil heat exchanger is found more effective than shell-single coil heat exchanger when the experimental results are compared with previous related work. Keywords: Solar hot water, Storage tank, Heat exchanger, Helical coil tube, Pressure drop, Effectivenes

The evolutionary history of a mammal species with a highly fragmented range: the phylogeography of the European snow vole.

The European snow vole Chionomys nivalis has a patchy distribution restricted to rocky habitats across southern Europe and the Near and Middle East. We carried out a phylogeographic study to provide a biogeographic scenario, based on molecular data, outlining the major processes that determined the current distribution of the species. The samples include 26 snow voles from 14 different populations across the entire species range from Spain to Anatolia and Israel. Nearly complete sequences (1037 bp) of the mitochondrial gene for cytochrome b were sequenced. Relationships among haplotypes were inferred with neighbourjoining, maximum likelihood, maximum parsimony analyses and minimum spanning network. An analysis of mismatch distribution was used to cast light on past demographic expansion. We found 22 different haplotypes that fall into six distinct lineages, all but one is supported by high bootstrap values with all methods. Four lineages are allopatric (Tatra Mts., Iberia, Balkans and Middle East) while divergent haplotypes from two lineages show sympatry in the Alps and the Apennines. The basal relationships of these lineages could not be established by any tree. The mean pairwise genetic distance between lineages ranges from 2.4 to 4.2%. The shape of the mismatch distribution indicated a past expansion event dating back to between 158 000 and 84 000 years ago. These data can be interpreted with the existence of southern glacial refugia (Iberia, Balkans, Middle East and Italy) and one additional northern glacial refugium. The lack of phylogenetic resolution among lineages and the shape of mismatch distribution are indicative of a simultaneous and rapid splitting due to a relatively fast initial expansion of populations. Moreover, the analysis supports the hypothesis of the European origin of C. nivalis and its subsequent eastward dispersion during the Middle Pleistocene