bluuebunny/crossref_metadata_2025_split huggingface dataset:
Propuesta de elaboración de un plan de vigilancia para la Norma Secundaria de Calidad Ambiental para la cuenca del rio Itata, Región del Biobío.
Authors: Pozo Katerine 
Published: June 2020

En el presente trabajo se elaboró una propuesta de plan de vigilancia, para la Norma Secundaria de Calidad Ambiental para la cuenca del río Itata, la cual incorpora a la normativa nacional de recursos hídricos el ámbito ecológico. Utilizando la información disponible en la base de datos de CONAMA Biobío y DGA se realizó un análisis espacial de la red de monitoreo DGA emplazada en la cuenca mediante el software ArcGis 9.2, y el respectivo análisis estadístico mediante ACP. Además de la integración de índices biológicos en la evaluación de calidad de agua, los cuales son; índices bióticos ChIBF y ChSIGNAL dado que han sido aplicados en trabajos realizados a ríos de la cuenca y ríos de las mismas características biogeográficas. Los índices de calidad de bosque de ribera (QBR) y hábitat fluvial (IHF), dado que un buen estado del entorno natural incide de manera decisiva en la calidad ecológica del cauce en términos de calidad de agua y biota asociada. Buscando introducir la bioindicación en la evaluación de calidad de agua, con el fin de proteger y conservar el componente ambiental del recurso hídrico, el cual es el objetivo de la Norma Secundaria de Calidad Ambiental.Palabras claves: Norma secundaria, plan de vigilancia, bioindicacion, calidad de agua.
Evaluation of Aluminium Phosphide Induced Testicular Toxicity in Wistar Rat: The Role of Allium sativum
Authors: Eric E. U. , Eseimo N. M. , Josiah V. F. 
Published: June 2020

Objectives: To investigate the ameliorative effect of garlic extract on Aluminum Phosphide induced toxicity on the testes of adult Wistar rats.
Materials: Thirty (30) male adult Wistar rats weighing 150±20 g – 200±20 g were purchased from Dantom Farms, Swali, Bayelsa State and moved to the animal house of the department of Medical Laboratory Science, Niger Delta University. The animals were assigned into six (6) major groups with five (5) animals in each group after the period of acclimatization: Animals in Group A (Control): received pelleted growers mash (feed) and water. Group B (Positive Control received 0.014 mg of Aluminum Phosphide only. Group C: received 0.014 mg of Aluminum Phosphide and 250g of garlic extract. Group D: received 0.014 mg of Aluminum Phosphide and 500 mg of garlic extract. Group E: received 500 mg of garlic extract, Group F: received 0.6 ml of oil at the end of the treatment, testes of each sacrificed rat was processed for paraffin sectioning and stained with Harris hematoxylin and eosin.
Results: Photomicrograph of testesfor animals in Groups B, C and D shows scanty spermatid which is as a result of spermatogenic arrest, thin basement membrane, abnormal structure of the spermatids and hypertrophy of the seminiferous tubules with diameter of 6.1 cm and 4.5 cm respectively, while animals in Group A,E,F shows a normal histology of the testis with the following features; circular and oval profile, closely packed and uniformly spaced with lumen containing numerous spermatids, with the diameter of seminiferous tubules measuring 2.4 cm – 3 cm.
Conclusion: The present study proves that the oral ingestion of Aluminum Phosphide induces hypertrophyin the testes of rats. However it also shows that the use of garlic (Allium sativum) at various concentrations (250 mg/l and 500 mg/l) has a mild ameliorative role on aluminum phosphide-induced testicular toxicity.
Evaluation of Serum Copper and Zinc Concentrations in Relation to Clinical Status among Adult People Living with HIV/AIDS in North-West Ethiopia
Authors: Birhanu Abera Admasu , Semahagn Bezuayehu Kerisew , Simegn Endalkachew Nibret , Eshetie Melaku Adal , Abitew Abayneh Munshea 
Published: June 2020

Aims: To evaluate serum copper (Cu) and zinc (Zn) concentration in relation to clinical status among people living with HIV/AIDS for possible interventions.
Study Design: A cross-sectional study design was used.
Place and Duration of Study: The study was conducted between January and February 2013 in Felege Hiwot Referral Hospital, Bahir Dar, Ethiopia.
Methods: Serum concentrations of Cu and Zn from 150 people living with HIV/AIDS were measured using a fully automated flame atomic absorption spectrophotometer. Besides, world health organization (WHO) clinical staging, CD4+ T-cell count, CD8+ T-cell count, hemoglobin determination, and Body Mass Index (BMI) were performed to evaluate the clinical status of study participants.
Results: Multivariate logistic regression analysis showed that being serum Zn and Cu deficient was higher where there is no antiretroviral therapy (ART) than on ART (adjusted odds ratio (AOR)=3.56, 95% confidence interval (CI)=1.52-8.33, P=0.003 and 5.85, 95% CI=1.22-28.058, P= 0.027respectively).Similarly, the odds of being serum Zn deficient were significantly associated to lower BMI than normal (AOR=2.61, 95% CI=1.02 - 6.67, P= 0.046) and abnormal hemoglobin was found to be a factor to having high serum Cu/Zn ratio than normal hemoglobin (AOR=3.26, 95% CI=1.07 - 9.94, P= 0.038).
Conclusions: A relatively high percentage of subjects had serum Cu and Zn deficiency and high serum Cu/Zn ratio. Early evaluation of serum Cu and Zn deficiency should be carried out and mineral supplementation along with antiretroviral treatment should be provided for pre-ART, malnourished and anemic people living with HIV/AIDS.
Le Corbusier and the creative use of mathematics
Authors: LOACH JUDI 
Published: July 2002

For the artist, mathematics does not consist of the various
branches of mathematics. It is not
necessarily a matter of calculation but rather of the presence of a sovereign
power; a law of
infinite resonance, consonance, organisation. Rigour is nothing other
than that which truly results
in a work of art, whether it be a Leonardo drawing, or the fearsome exactness
of the Parthenon
(comparable in the cutting of its marble even with that of
machine-tools), or the implacable and
impeccable play of construction in the cathedral, or the unity in a
Cézanne, or the law which
determines a tree, the unitary splendour of roots, trunk, branches, leaves,
flowers, and fruit.
Chance has no place in nature. Once one has understood what mathematics
is – in the
philosophical sense – thereafter one can discern it in all
its works. Rigour, and exactness, are the
means behind achieving solutions, the cause behind character, the rationale
behind harmony.Le Corbusier, 1948Probably everyone reading this article has heard of Le Corbusier, no
doubt the most
famous architect this century, but the images he will arouse in their minds
may vary
greatly. Some will blame him for those theories promoting standardized
high rise
construction, which have dominated town planning policy in post-war Europe.
Others will
admire his highly individual, sculptural buildings such as the church at
Ronchamp
(1950–55) (see Figure 1), the revolutionary public housing scheme
of the
Unité d'Habitation
at Marseilles (1946–52) (Figure 2), its ground-level pillars
(pilotis) and roof-level service
stacks alike transformed into enigmatic statues, or his pre-war Purist
villas in the Paris
suburbs (1920s). His work displayed a wide variety of forms and spaces
at any one time,
and his career spanned almost sixty years, during which he was constantly
questioning, and
reformulating theories, and in consequence changing his formal language.
THE CROSSED PRODUCT BY A POINTWISE UNITARY ACTION ON A C*-ALGEBRA WITH CONTINUOUS TRACE
Authors: Deicke Klaus 
Published: July 2002

AbstractLet $G$ be a locally compact group, $A$ a continuous trace $C^*$-algebra, and $\alpha$ a pointwise unitary action of $G$ on $A$. It is a result of Olesen and Raeburn that if $A$ is separable and $G$ is second countable, then the crossed product $A\times_\alpha G$ has continuous trace. We present a new and much more elementary proof of this fact. Moreover, we do not even need the separability assumptions made on $A$ and $G$.AMS 2000 Mathematics subject classification: Primary 46L55
PUNT AND AKSUM: EGYPT AND THE HORN OF AFRICA
Authors: PHILLIPS JACKE 
Published: July 2002

The ancient Egyptians tended to consider both their immediate and
more

remote neighbours either as excellent sources of luxury trade items and

slaves, at times of political power and strength, or as uncivilized forces

threatening to destroy and overwhelm the Egyptian Nile Valley. This was

true not only of cultures within Africa; those in the Aegean, the Levant,

Cyprus and Mesopotamia also were viewed from one or the other perspective,

occasionally both at the same time. All these, together with Nubia and
Libya,

have received much scholarly attention and, whilst we probably will never

fully understand their ancient relationship to Egypt, we have a fairly
good

idea, ‘hearing’ the story from both sides when surviving evidence
allows,

what their attitudes towards each other were at various times in their
history.This article deals with what is surely the least investigated aspect
of

ancient Egyptian relations with its neighbours, simply because we know

comparatively little about the two major successive cultures concerned
–

Punt and Aksum – in the ancient world.
Phosphorus leaching from liquid digested sewage sludge applied to sandy soils
Authors: SHEPHERD M. A. , WITHERS P. J. 
Published: July 2002

The aim of the experiment was to determine the importance of liquid digested sewage sludge (‘sewage sludge’) as a source of phosphorus leaching from sandy soils in the UK. The sewage sludge was applied to uncropped loamy sand and sandy loam monolith lysimeters (1·2 m deep) annually for 3 years. The application rate was sufficient to supply approximately 60 kg P/ha annually. An application equivalent to four times this amount was also applied to two other loamy sand lysimeters to test the effects of excessive amounts. Total P (TP), total dissolved P (TDP) and molybdate-reactive P (MRP) concentrations were measured in the drainage water and were compared with leaching from untreated control soils.After two sewage sludge applications, Olsen's extractable P content of the topsoil had increased: a P surplus of c. 100 kg/ha was required to raise the topsoil concentration by 5 mg/kg. Sewage sludge applications at the lower rate did not increase P concentrations in the drainage. Phosphorus concentrations were generally small and were, as an average of both soil types and nil and lower rate sludge applications, 12, 20 and 34 μg/l for MRP, TDP and TP respectively. Phosphorus leaching losses from the higher rate (excessively large sewage sludge applications) were more variable but not significantly (P > 0·05) different from the other treatments. Average concentrations were 9, 23 and 50 μg/l for MRP, TDP and TP respectively. Leaching from sludge biosolid applications at operational rates to sandy soils moderately well supplied with P is not a major P loss pathway.
Phosphorus homoeostasis in grazing breeder cattle
Authors: TERNOUTH J. H. , COATES D. B. 
Published: July 2002

The phosphorus (P) balances and
32P kinetics of 15 Droughtmaster heifers were studied in mid and
late pregnancy and early and late lactation to compare their P absorption
coefficients and their P
endogenous faecal losses with those of growing cattle. The heifers continuously
grazed three
paddocks of tropical pasture for a year to provide a range of P intakes.The daily dry matter (DM) and P intakes of the heifers were generally much
higher during lactation
(17–26 g DM/kg LW and 11–40 mg P/kg LW) than during
pregnancy (10–16 g DM/kg LW and
6–22 mg P/kg LW), due in part to the heifers calving at the beginning
of the wet (pasture growing)
season. Plasma inorganic P levels decreased as the experiment progressed and
were very low
(<30 mg/l) in all treatments in late lactation. Milk and milk P secretion
were high in early lactation
(4·0–5·5 l/day and 12–16 mg P/kg LW per day)
so the heifers were in more negative balance during
lactation than during pregnancy.The coefficient of P absorption was similar to that previously observed in
growing cattle consuming
forage diets and it was concluded that 0·75 was the appropriate value to use
in the estimation of
requirements. Endogenous faecal losses ranged from 7 to 17 mg/kg LW and were
related to P intake
or DM intake plus plasma inorganic P. Comparison of the regressions with those
from the larger data
set for growing cattle showed that the endogenous faecal losses were similar
and there were no special faecal endogenous losses in breeding cattle.
Effects of phosphorus fertilizer sources on cowpea
and subsequent cereal crop productivity in semi-arid
West Africa
Authors: MULEBA N. , COULIBALY M. 
Published: July 2002

A natural rock phosphate, ‘Kodjari” (RP), sparingly
soluble, indigenous to Burkina Faso, and a
commercial single superphosphate (SSP) fertilizer were studied at Farako-Bâ in
the Northern Guinea
Savannah (NGS) and at Oipasse in the Sudan Savannah (SS) regions of Burkina
Faso. A 3-year crop
sequence either of cowpea, maize and sorghum or of cowpea, sorghum and
sorghum was used,
respectively, in the NGS and SS regions. The sorghum crop in the third
year was not fertilized with
any phosphorus (P) source. The objectives of the research were to study
the direct and residual effects
of the P fertilizers on soil fertility improvement in order to boost agricultural
productivity in both
regions.Cowpea daylength-insensitive cultivars, in both regions, and maize and
sorghum in the NGS and
SS regions, respectively, responded more strongly to SSP than to RP fertilizer
treatments. The
optimum rate of SSP and RP source was 21·8 kg P/ha and 43·6
kg P/ha, respectively, for cowpea in
both regions. The optimum rates of phosphorus fertilizer applied in the
second year to maize in the
NGS and to sorghum in the SS region, in addition to the optimum rate of
P applied to cowpea the
previous year, was 10·9 kg P/ha of SSP or 43·6 kg P/ha
of RP, and 21·8 kg P/ha of SSP or
43·6 kg P/ha of RP, respectively. Both P sources had significant
residual effects for up to 2 years. The
agronomic effectiveness of RP relative to SSP, in the year of application
of both fertilizers, was
greater for cowpea than for maize in the NGS region and similar for cowpea
and sorghum in the SS
region; it increased markedly for the two subsequent cereal crops in both
regions. Cowpea
fertilization with both P sources proved, therefore, to be effective in
improving the soil fertility and
boosting the productivity of cereal crops in the 3-year crop sequence.
C and N mineralization of composted and
anaerobically stored ruminant manure in differently
textured soils
Authors: THOMSEN INGRID K. , OLESEN JØRGEN E. 
Published: July 2002

Three animal manures cross-labelled with 15N in either the urine, faeces or straw fractions were
prepared. After a storage period of 86 days when the manures were exposed to either composting or
to anaerobic storage, portions of the manures were incubated in six differently textured soils with clay
contents ranging from 11 to 45%. Evolved CO2-C was determined during a 266 day incubation and
inorganic N and 15N in soil were measured at the termination of the incubation. The mineralization
of C was analysed using first-order kinetics, and two C pools with fast (P1) and slow (P2) turnover
rates were estimated. The total conversion of added C (Ps) was estimated as Ps=P1+P2.The cumulated CO2 production was considerably higher from soils incubated with anaerobically
stored manure compared with soils amended with composted manure. CO2 production levelled off
after c. 60 days in the three sandier soils whereas CO2 continued to be produced throughout the
incubation from the three soils with the highest clay content. More C was assigned to the easily
decomposable P1 pool in the sandiest soils whereas the more recalcitrant P2 pool was larger in the soils
with higher clay content. Because of the different relationships between soil texture and C pools, Ps
ended up being similar for five of the six soils. When taking C losses during the preceding storage into
account, the accumulated C losses during storage and after incubation in soil accounted for 60 and
54% of C initially present in the composted and anaerobically stored manure, respectively.Net N mineralization which averaged 16% of applied organic N took place in all soils amended
with composted manure. Soils with anaerobically stored manure showed net immobilization after the
266 days of incubation. The amount of N immobilized accounted for up to 30% of the inorganic N
applied with the manure. As anaerobically stored manure generally loses less inorganic N during
storage, it may contain more inorganic N than composted manure at the time of field application.
Because of the immobilization that takes place after application of anaerobically stored manure to
soil, the immediate levels of plant available N in soil may not be as different from soil supplied with
composted manure as could be expected from the inorganic N content in the two types of manure.
However, when considering the manure as a N resource, anaerobic storage is superior to composting.
Dr M. Elisabeth Sharpe
Authors: Bramley A. J. 
Published: July 2002

Dr M. Elisabeth Sharpe, who died last year, was Editor of the Journal of Dairy
Research from 1975 to 1989. During this period she devoted her considerable energies
and talent to putting the Journal on a sound financial footing and expanding its
contributions from authors in the developing world. Becky, as she was known to her
friends and colleagues, was highly successful in both these goals and the Journal
continues to build upon her success to this day.Her editorship was the culmination of a notable scientific career, full of
achievement and friendships. Born in 1916 in Barnsley, Yorkshire, Becky Sharpe
completed her BSc degree at University College London in 1937 and went on to a
year of postgraduate study in microbiology at the University of Manchester. She
then joined the staff of the National Institute for Research in Dairying, Shinfield, an
Agricultural Research Council Institute and a part of the University of Reading. She
left in 1942 for a 4 year stint with The Boots Company in Nottingham and returned
to Shinfield for a 30 year period of exemplary research in dairy microbiology in the
Department of Bacteriology.The Department had a tremendous group of researchers and was a really exciting
place for many of us to start our careers working with people like Becky Sharpe,
Bruno Reiter, Frank Neave and Christina Cousins. Becky interacted with many of
us over her career, and her research resulted in hundreds of publications and
contributions to the scientific literature on the microbiology and microflora of milk
and dairy products. She is probably best remembered for her work on staphylococci,
micrococci and the lactobacilli. Often she pioneered the development of new
techniques for the growth, isolation and identification of these Gram-positive
organisms. She was especially pleased with her work as a contributor and editor for
Bergey's Manual of Systematic Bacteriology, which continued after retirement. She
received her PhD from the University of Reading in 1951 and a DSc degree from the
University of London in 1973.On a more personal note, the author remembers Becky as a generous and
stimulating scientific colleague. She was always willing to listen to the ideas of a
young and inexperienced scientist and offer help and advice. She was highly
respected and well known in the world of dairy microbiology, and many outstanding
microbiologists either worked with her or trained under her. Her laboratory was a
favoured stop for researchers from across the globe.After retiring from active research in 1976 she remained very active in scientific
circles. Her Editorship of the Journal was a major commitment, but she was also an
active participant in scientific society activities, particularly as a fellow of the
Institute of Biology. Her numerous scientific contributions, and the health and
international flavour of the Journal speak to her professional accomplishments. Her
friendship and help will be fondly remembered and missed by all of those fortunate
enough to have worked with her.
Görtler vortices in compressible mixing layers
Authors: SARKIES J. M. , OTTO S. R. 
Published: July 2002

In experiments, Plesniak, Mehta & Johnson (1994) have noted that curved two-stream
mixing layers are susceptible to centrifugal instabilities under the condition that the
slower of the streams curves towards the faster one; this condition is analogous to
the concave curvature condition for the stability of the flow over a plate. The modes
which arise manifest themselves as vortices aligned with the dominant flow direction.
Previous numerical and analytical work has elucidated the structure of these vortices
within incompressible mixing layers; Otto, Jackson & Hu (1996). In this paper we
go on to investigate the rôles of compressibility and heating in determining the
streamwise fate of Görtler vortices within these situations.The development of the disturbances is monitored downstream and curves of
neutral stability are plotted. The effect of changing the Mach number and free-stream
temperatures is studied in detail. It is found that for certain parameter régimes modes
can occur within convexly curved, or ‘stable’ mixing layers; these ‘thermal modes’
have no counterpart within incompressible mixing layers. By making use of a large
Görtler number analysis we are able to verify our numerical results, and derive a
very simple condition which yields information about the parameter ranges for which
certain modes are likely to occur. As an aside this method can be used to show
that no degree of wall cooling will allow sustained growth of Görtler vortices within
boundary layers over convex plates.
Statistical mechanical description and modelling of turbulent collision of
inertial particles
Authors: WANG LIAN-PING , WEXLER ANTHONY S. , ZHOU YONG 
Published: July 2002

The collision rate of monodisperse solid particles in a turbulent gas is governed by
a wide range of scales of motion in the flow. Recent studies have shown that large-scale energetic eddies are the dominant factor contributing to the relative velocity
between two colliding particles (the turbulent transport effect), whereas small-scale
dissipative eddies can enhance the collision rate significantly by inducing local non-uniform particle distribution (the accumulation effect). The turbulent transport effect
is most noticeable when the particle inertial response time τp is of the order of the
flow integral timescale and the accumulation effect is most pronounced when τp is
comparable to the flow Kolmogorov time.We study these two contributions separately through direct numerical simulations.
The two effects are quantified carefully with a numerical procedure that is independent
of the computation of average collision rate. This facilitates the study of not only the
statistical description of the collision kernel, but also the relative contributions and
modelling of the two physical effects. Simulations at several flow Reynolds numbers
were performed to suggest a model for the accumulation effect. The data show that
the accumulation effect scales linearly with flow Taylor microscale Reynolds number
Rλ, while the theory for fully developed turbulence indicates that the maximum level
of the turbulent transport effect scales with R1/2λ. Finally, an integrated model has
been developed to predict the collision rate at arbitrary flow Reynolds numbers and
particle inertia.