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Iron deficiency remains the most common nutritional deficiency. Oral iron supplementation is the recommended first line treatment and used as a preventive measure as well. Enhancers of iron absorption are highly sought after to improve supplementation outcomes. Evidence from animal and human studies exists that prebiotics can enhance iron absorption. The purpose of this present narrative review of the literature was to summarize the existing evidence on the effects of prebiotics on human iron absorption. Relevant articles were identified from Pubmed, Scopus and Web of Science from inception to November 2021. Only human trials investigating the effect of prebiotics on iron absorption were included. 11 articles were identified and included for review. There are promising findings supporting an enhancing effect of certain prebiotics, but inconsistencies between the studies and results exist. The most convincing evidence exists for the prebiotics galacto-oligosaccharides and fructo-oligosaccharides combined with the commonly used iron compound ferrous fumarate, from studies in adult women with low iron stores and anemic infants. Many factors seem to play a role in the enhancing effect of prebiotics on iron absorption such as type of prebiotic, dose, acute (single dose) or chronic (long term feeding) prebiotic consumption, iron compound, iron status, inflammatory status, and age of the population studied. More research investigating the optimal combination of prebiotic, iron compound and dose as well as the effect of long-term application on iron status outcomes is needed.

The Measurement Model of Derivatives (MMOD; Estabrook, 2015) provides the opportunity to evaluate and refine measurement scales used in longitudinal studies to clarify their theoretical distinctions and relationship to academic achievement. We demonstrate this using three teacher-rated scales of child self-regulatory behavior obtained from the Early Childhood Longitudinal Study Kindergarten Class of 2010-11 (ECLS-K:2011; Tourangeau et al., 2019). Data-driven factor structures were generated using a training sample (N = 2821), then compared using the MMOD to the theoretical measurement structure on a holdout sample (N = 2822). Finally, to externally validate their utility, the best-fitting data-driven measurement structure was compared to the theoretical structure in their ability to predict academic achievement on a validation sample (N = 5643). We discuss theoretical implications for self-regulation, as well as the MMODs applicability to other educational data sets.

A possibility to improve the luminosity in hadron colliders is to apply electron cooling. For the e–p and possibly in the future for e-ion a cooling scheme is proposed for the HERA collider which improves the brightness of the hadron beam in two steps. In a first step the hadron beam is cooled at an energy of 15–20 GeV in the pre-accelerator PETRA. In a second step the hadrons are cooled at top energy in HERA, mainly to maintain the beam quality. The first part of the cooler in PETRA consists of a thermionic gun which delivers electron bunches of 120 keV. These bunches are then compressed so that they fit into a 208 MHz travelling wave linac where they are accelerated to an energy of 10 MeV. Gun, compressor, and linac are surrounded by a solenoid so that emittance growth is avoided especially at the low energy end. In order to reduce the energy spread of the electron beam and to lengthen it, the electrons run through a decompressor before they are brought together with the hadron beam in a 40 m long cooling section which is again surrounded by a solenoid. In this paper a schematic layout of the system will be presented and simulation results of the first part of the cooler will be shown. The cooler in HERA consists of a small electron storage ring with two long straight sections. It is shown that all requirements of such a ring running at an energy between 180 and 450 MeV can be met to fight emittance growth in case of light hadron beams (protons) and to cool heavy ions sufficiently fast.

It is under discussion to operate HERA with heavy ions instead of protons. Because of the heavily increased intrabeam scattering of heavy ions compared to protons, the achievable luminosity is much smaller than desired by the experiments. A way to increase luminosity could be electron cooling of the heavy ion beam. Because of the high electron energy of 180 MeV necessary for cooling heavy ions in HERA the conventional approach using electrostatic DC sources is not possible. Instead an electron storage ring could be used. For this ring there are special requirements like small damping times, emittances and energy spread. The feasibility of such an electron storage ring has been studied, and the results with a possible solution are presented in this paper. Electron cooling of the HERA proton beam is also discussed briefly.

At the 3.5 GeV electron accelerator ELSA of Bonn University, polarized electrons have been accelerated up to 2.0 GeV, crossing several depolarizing resonances without significant depolarization. The polarized electrons were produced by photoemission from an AlGaAs–GaAs superlattice crystal using circularly polarized laser light. A harmonic correction scheme was successfully applied to the third imperfection resonance ( γa =3) and the polarization required for the planned experiments was conserved up to 2.0 GeV.

Angular distributions of the differential cross section for the reaction γ +p→ π 0 +p have been measured at the Bonn 2.5 GeV Synchrotron at c.m. angles between 0° and 65° in the energy range from 1.3 GeV to 2.2 GeV. The π 0 mesons were detected by their two decay photons. The data are compared with data of other laboratories and the Metcalf-Walker analysis.

Angular distributions of the target symmetry for the reaction γ + p → π0 + p have been measured at the Bonn 2.5 GeV Electron Synchrotron at pion c.m. angles between 13° and 63° and photon energies of 1.0 and 1.1 GeV. The π0 mesons were detected by their two decay photons with total absorption lead-glass Cerenkov counters. Butanol was used as target material in a continuous flow 3He cryostat operating at 0.5 K and 25 kG. The π0 counting rate from free protons in the butanol target was derived from the measurements of the differential cross section on hydrogen. The data are compared with data of other laboratories and the results of two recent partial-wave analyses.

Four angular distributions of the differential cross section of the reaction γ + p → π 0 + p have been measured at the Bonn 2.5 GeV Synchrotron at pion c.m. angles between 3° and 63° in the photon energy range from 0.9 GeV to 1.2 GeV. The π 0 mesons were detected by their two decay photons. The data are compared with data of other laboratories and predictions of two recent partial-wave analyses.

The polarization degree of accelerated longitudinally polarized electrons has been measured employing the spin dependence of the elastic electron-electron cross section. We observe strong depolarization as well as polarization flips in the neighbourhood of imperfection and intrinsic resonances. Measures to maintain the initial polarization degree up to the highest available energies are discussed.

The differential cross section of the reaction γ + p → p + πo has been measured at the Deutsches Elektronen- Synchrotron, Hamburg, at mean phonon energies of 1.36, 2.0 and 3.0 GeV and pion center of mass angles between 0o and 70o. The results are compared with some theoretical calculations based on elementary and reggeized 1- meson exchange.

The differential cross-section of the reaction γ + p → p + π0was measured at the Deutsches Elektronen-Synchrotron, Hamburg, at mean photon energies of 4.0, 5.0 and 5.8 GeV and pion center of mass angles between 0° and 60°. The results are compared wiht theoretical calculations based on Reggeized vector meson exchange.