Updated single and dual crop coefficients for tree and vine fruit crops

ReviewThe present study reviews the research on the FAO56 crop coefficients of fruit trees and vines performed over the past twenty years. The main objective was to update information and extend tabulated single (Kc) and basal (Kcb) standard crop coefficients. The selection and analysis of the literature for this review have been done to consider only studies that adhere to FAO56 method, computing the reference ET with the FAO Penman– Monteith ETo equation and field measuring crop ET with proved accuracy. The crops considered refer to vine fruit crops, berries and hops, temperate climate evergreen fruit trees, temperate climate deciduous fruit trees and, tropical and subtropical fruit crops. Papers satisfying the conditions expressed above, and that studied the crops under pristine or appropriate eustress conditions, were selected to provide for standard Kc and Kcb data. Preference was given to studies reporting on the fraction of ground cover (fc), crop height (h), planting density, crop age and adopted training systems. The Kc and Kcb values obtained from the selected literature generally show coherence relative to the crop biophysical characteristics and reflect those characteristics, mainly fc, h and training systems. The ranges of reported Kc and Kcb values were grouped according to crop density, particularly fc and h, and were compared with FAO56 (Allen et al., 1998) previously tabulated Kc and Kcb values, as well as by Allen and Pereira (2009) and Jensen and Allen (2016), which lead to define update indicative standard Kc and Kcb values. These values are aimed for use in crop water requirement computations and modeling for irrigation planning and scheduling, thus also aimed at supporting improved water use and saving in orchards and vinesinfo:eu-repo/semantics/publishedVersio

Circumcision and penile human papillomavirus prevalence in human immunodeficiency virus-infected men: heterosexual and men who have sex with men

AbstractMale circumcision is associated with a lower risk of penile human papillomavirus (HPV) infection in human immunodeficiency virus (HIV) uninfected men. Few studies have evaluated the role of male circumcision in penile HPV infection in HIV-infected men. The aim of this cross-sectional study was to examine the association between male circumcision and the prevalence of penile HPV infection among HIV-infected men—both men who have sex with men (MSM) and heterosexual men. Samples from 706 consecutive men included in the CARH-MEN cohort (overall 24% circumcised: 26% of MSM, 18% of heterosexual men) were examined by Multiplex-PCR. In the overall group (all HIV-infected men included), the prevalence of any penile HPV infection was 22% in circumcised men and 27% in uncircumcised men (OR = 1.0, 95% CI 0.6–1.6, adjusted analysis). In the circumcised group the overall prevalence of HPV infection was 22% in MSM and 24% in the heterosexual men, whereas in the uncircumcised group the prevalence was 26% and 28%, respectively. The prevalence of high-risk HPV types tended to be lower in the circumcised MSM (14% vs 21%, OR = 0.6, 95% CI 0.3–1.1, p 0.088), but it was similar in the heterosexual men (18% in circumcised vs 20% in uncircumcised). These results suggest that male circumcision may be associated with a lower prevalence of oncogenic high-risk penile HPV infection in HIV-infected MSM

Equilibrium properties of self-interacting neutrinos in the quasi-particle approach

In this work a neutrino gas in equilibrium is studied both at T=0 and at finite temperature. Neutrinos are treated as massive Dirac quasi-particles with two generations. We include self-interactions among the neutrinos via neutral currents, as well as the interaction with a background of matter. To obtain the equilibrium properties we use Wigner function techniques. To account for corrections beyond the Hartree approximation, we also introduce correlation functions. We prove that, under the quasi-particle approximation, these correlation functions can be expressed as products of Wigner functions. We analyze the main properties of the neutrino eigenmodes in the medium, such as effective masses and mixing angle. We show that the formulae describing these quantities will differ with respect to the case with no self-interactions.Comment: 17 pages, no figure

The MSW Effect in Quantum Field Theory

We show in detail the general relationship between the Schr\"{o}dinger equation approach to calculating the MSW effect and the quantum field theoretical S-matrix approach. We show the precise form a generic neutrino propagator must have to allow a physically meaningful ``oscillation probability'' to be decoupled from neutrino production fluxes and detection cross-sections, and explicitly list the conditions---not realized in cases of current experimental interest---in which the field theory approach would be useful.Comment: 20 page REVTeX file, submitted to Phys. Rev.

Solvent-free formation of cyclodextrin-based pseudopolyrotaxanes of polyethylene glycol: kinetic and structural aspects

Pseudopolyrotaxanes (PPRs) are supramolecular structures consisting of macrocycles able to thread on a linear polymer chain in a reversible, non-covalent way, often referred to in the literature as "molecular necklaces". While the synthesis and reaction mechanisms of these structures in solution have been widely described, their solvent-free production has received little attention, despite the advantages that this route may offer. We propose in this work a kinetic mechanism that describes the PPR formation in the solid phase as a process occurring in two consecutive stages. This mechanism has been used to investigate the spontaneous formation of a PPR that occurs when grinding alpha-Cyclodextrin (alpha-CD) with polyethylene glycol (PEG). In the threading stage, the inclusion of the polymer and subsequent release of the water molecules lodged in the cavity of the macrocycle cause vibrational changes that are reflected in the time-dependence of the FTIR-ATR spectra, while the further assembly of PPRs to form crystals produces characteristic reflections in the XRD patterns, due to the channel-like arrangement of CDs, that can be used to track the formation of the adduct in crystalline form. The effects that working variables have on the kinetics of the reaction, such as temperature, feed ratio, molar mass of the polymer and the introduction of an amorphous block in the polymer structure, have been investigated. The rate constants of the threading step increase with the temperature and the activation energy of the process increases at lower proportions of CD to PEG. This is attributed to the lower degree of covering of the polymer chain with CDs that reduces the hydrogen-bonding driven stabilization between adjacent macrocycles. The formation of crystalline PPR, which takes place slowly at room temperature, is markedly promoted at higher temperatures, with lower proportions of CD favoring both the formation and the growth of the crystals. The molar mass of the polymer does not modify the typical channel-like arrangement of packed PPRs but the conversion into crystalline PPR diminishes when using PEG1000 instead of PEG400. At a microscopic level, the crystals arrange into lamellar structures, in the order of hundreds of nm, embedded in an amorphous-like matrix. The introduction of a polypropylene oxide block in the structure of the polymer (Pluronic L62) renders poorer yields and a considerable loss of crystallinity of the product of the reaction. The methodology here proposed can be applied to the general case of inclusion complexes of CDs with drugs in the solid phase, or to multicomponent systems that contain polymers as excipients in pharmaceutical formulations along with CDs

The impact of antiretroviral therapy on HPV and cervical intraepithelial neoplasia: current evidence and directions for future research

Increasing numbers of human immunodeficiency virus (HIV)-infected women are now accessing life-prolonging highly active antiretroviral therapy (HAART) in developing countries. There is a need for better understanding of interactions of human papillomavirus (HPV) and HIV, especially in the context of increasing life expectancy due to HAART. The data regarding the impact of HAART on reducing the incidence and progression and facilitating the regression of HPV infection and cervical abnormalities is largely inconsistent. Published studies differ in their study designs (prospective or retrospective cohorts or record linkage studies), screening and diagnostic protocols, duration and type of HAART use, recruitment and referral strategies, and definitions of screening test and disease positivity. Due to the ethical and resource limitations in conducting randomized trials of the impact of HAART on incidence of HPV, CIN, and cervical cancer among HIV-infected women, it is important to consider innovative study designs, including quasi-experimental trials and operations research in sentinel populations to answer the critical research questions in this area

Relativistic Wigner Function Approach to Neutrino Propagation in Matter

In this work we study the propagation of massive Dirac neutrinos in matter with flavor mixing, using statistical techniques based on Relativistic Wigner Functions. First, we consider neutrinos in equilibrium within the Hartree approximation, and obtain the corresponding relativistic dispersion relations and effective masses. After this, we analyze the same system out of equilibrium. We verify that, under the appropiate physical conditions, the well known equations for the MSW effect are recovered. The techniques we used here appear as an alternative to describe neutrino properties and transport equations in a consistent way.Comment: 18 pages, no figures. Revte

Gender differences in the use of cardiovascular interventions in HIV-positive persons; the D:A:D Study

Peer reviewe