4,172 research outputs found
Root Zone Sensors for Irrigation Management in Intensive Agriculture
Crop irrigation uses more than 70% of the worldâs water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the growerâs experience or on the determination of soil water balance (weather-based method). An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS), such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZSâ (for both soil moisture and salinity) marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy) on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy
Predicting the effect of improved socioeconomic health determinants on the tuberculosis epidemic
Two important public health documents have recently established programmatic goals for tuberculosis control. The first is WHO's End TB Strategy, which represents the evolution of previous DOTS (directly observed treatment, short-course) and Stop TB strategies.1 End TB is built around three pillars: pillar 1 focuses on diagnosis, treatment, and prevention; pillar 2 on ways to tackle socioeconomic factors (eg, poverty reduction, social protection, and universal access); and pillar 3 on scientific research
Restricted three-body problem in effective-field-theory models of gravity
One of the outstanding problems of classical celestial mechanics was the
restricted 3-body prob- lem, in which a planetoid of small mass is subject to
the Newtonian attraction of two celestial bodies of large mass, as it occurs,
for example, in the sun-earth-moon system. On the other hand, over the last
decades, a systematic investigation of quantum corrections to the Newtonian
potential has been carried out in the literature on quantum gravity. The
present paper studies the effect of these tiny quantum corrections on the
evaluation of equilibrium points. It is shown that, despite the extreme
smallness of the corrections, there exists no choice of sign of these
corrections for which all qualitative features of the restricted 3-body problem
in Newtonian theory remain unaffected. Moreover, first-order stability of
equilibrium points is characterized by solving a pair of algebraic equations of
fifth degree, where some coefficients depend on the Planck length. The
coordinates of stable equilibrium points are slightly changed with respect to
Newtonian theory, because the planetoid is no longer at equal distance from the
two bodies of large mass. The effect is conceptually interesting but too small
to be observed, at least for the restricted 3-body problems available in the
solar system.Comment: 20 pages, latex, 8 figure
Influences on Foster Care Reentry Rate
Influences on Foster Care Reentry Rate looked at demographic and socioeconomic characteristics in each state within the United States. Those characteristics were then studied to see how they related to foster care reentry rates. Then, a case study analysis was conducted on three states, Minnesota, North Carolina, and Tennessee, because of their similarity in demographic and socioeconomic characteristics and divergence in foster care reentry rates. The case analysis was an in depth pursuit of differences in each of the state\u27s policies that may be a driving force of higher reentry rates
Frequency Shifts in Natural Vibrations in Pantographic Metamaterials under Biaxial Tests
In this paper a 2D continuum model, thought as the homogenized limit of a microstructured pantographic sheet, is studied. The microstructure is characterized by two families of parallel fibers, whose deformation measures account for bending, elongation and relative rotation of the fibers. The deformation energy density of the homogenized model depends on both first and second gradients of the displacement. Modal analysis is performed in order to assess the peculiarities of the dynamic behavior of higher gradient models, and in particular the difference, with respect to classical laminae, in the dependence of the eigenfrequencies on the stiffness
High prevalence of anti-hepatitis e virus antibodies among blood donors in central Italy, february to march 2014
Prevalence of anti-hepatitis E virus (HEV) antibodies is highly variable in developed countries, which seems partly due to differences in assay sensitivity. Using validated sensitive assays, we tested 313 blood donors attending a hospital transfusion unit in central Italy in January and February 2014 for anti-HEV IgG and IgM and HEV RNA. Data on HEV exposure were collected from all donors. Overall anti-HEV IgG prevalence was 49% (153/313). Eating raw dried pig-liver sausage was the only independent predictor of HEV infection (adjusted prevalence rate ratio = 2.14; 95% confidence interval: 1.23â3.74). Three donors were positive for either anti-HEV IgM (n = 2; 0.6%) or HEV RNA (n = 2; 0.6%); they were completely asymptomatic, without alanine aminotransferase (ALT) abnormalities. Of the two HEV RNA-positive donors (both harbouring genotype 3), one was anti-HEV IgG- and IgM-positive, the other was anti-HEV IgG- and IgM-negative. The third donor was positive for anti-HEV IgG and IgM but HEV RNA-negative. HEV infection is therefore hyperendemic among blood donors (80% men 18â64 years-old) from central Italy and associated with local dietary habits. Nearly 1% of donors have acute or recent infection, implying potential transmission to blood recipients. Neither ALT nor anti-HEV IgM testing seems useful to prevent transfusion-transmitted HEV infection. © 2016, European Centre for Disease Prevention and Control
Electronic cigarette: a threat or an opportunity for public health? State of the art and future perspectives
The e-cigarette, also known as e-cig, represents an emerging issue
of great concern for public health. The aim of the present report was
to explore the scientific literature about the use of electronic cigarette
(e-cig), with a particular reference to the features of âtoxicological
safetyâ, âeffectiveness in overcoming the addiction to smoking the
traditional cigaretteâ and ânecessary research agendaâ. The efficacy
of e-cig for smoking cessation is uncertain: some authors found that it
can be a valid support, but long-term cessation rate has not be assessed.
Other studies evidenced that e-cig is often used not for quitting smoking but to avoid smoking ban for traditional cigarettes and, even, some
researches evidenced that it appears to contribute to nicotine addiction.
E-cig smoking seems to be less dangerous of conventional cigarettes,
but its use is not risk-free. Besides, cases of accidental or intentional
poisoning with liquid solutions of e-cig have been reported. Also, the
smoke of e-cig decreases indoor air quality, releasing particulate matter
and other toxics that can persist on surfaces for days and generating
passive exposure. These phenomena are similar to environmental
tobacco smoke produced by conventional smoking, that is the sum of
second- and third-hand smoke. We propose to call them âenvironmental
electronic smokeâ, âelectronic-second- hand smokeâ and âelectronicthird-hand smokeâ, respectively. Uncertainties relating to e-cig features
determined the sequence, in the short term, of warnings and regulations
approved and then replaced. In conclusion, although in recent years
many researches were performed, evidences is limited and there is a
need to study in deep all these issues
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