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Molecular structure of citric acid cross-linked starch films

The effect of citric acid (CA) on starch films has been examined. A new method to detect cross-linking of starch by CA in solution-cast films by molecular weight measurements is described. Furthermore, we managed to distinguished between free, mono- and di-esterified CA and quantify di-ester content within starch films by using a modification in the method of complexometric titration with copper(I

Power Based Multi-Cell Call Admission Control Scheme for Wideband-CDMA Systems

Wideband code division multiple access (WCDMA) systems are interference-limited. When a WCDMA system operates at nearly full capacity, admitting a new user may affect the stability of the system. Therefore, the proper call admission control (CAC) is crucial and should balance between quality of service (QoS) requirements for the new user as well as for the existing users and the required high capa

Water soluble contrast enema examination of the integrity of the rectal anastomosis prior to loop ileostomy reversal may be superfluous

Defunctioning loop ileostomy in low anterior resection (LAR) is routinely used to reduce consequences of anastomotic leakage. The purpose of this study was to analyze which examination technique is optimal for evaluating the integrity of the anastomosis prior to loop ileostomy reversal. Retrospective analysis of 95 patients who had been subjected to LAR at Helsingborg Hospital and SkAyenne Univers

Probing Time-Dependent Molecular Dipoles on the Attosecond Time Scale

Photoinduced molecular processes start with the interaction of the instantaneous electric field of the incident light with the electronic degrees of freedom. This early attosecond electronic motion impacts the fate of the photoinduced reactions. We report the first observation of attosecond time scale electron dynamics in a series of small-and medium-sized neutral molecules (N-2, CO2, and C2H4), m

Three cryptic species in Asecodes (Förster) (Hymenoptera, Eulophidae) parasitizing larvae of Galerucella spp. (Coleoptera, Chrysomelidae), including a new species.

Three morphologically very similar species of Asecodes Förster (Hymenoptera: Eulophidae) are reviewed. Asecodes parviclava (Thomson) is removed from synonymy under A. lucens stat. rev., and differentiated from A. lucens (Nees) and A. lineophagum sp. n. All three species develop as gregarious endoparasitoids in larvae of Galerucella spp. (Coleoptera: Chrysomelidae), but each species has its own uni

A Modeling and Simulation Study of the Role of Suspended Microbial Populations in Nitrification in a Biofilm Reactor.

Many biological wastewater treatment processes are based on bacterial biofilms, i.e. layered aggregates of microbial populations deposited on surfaces. Detachment and (re-)attachment leads to an exchange of biomass between the biofilm and the surrounding aqueous phase. Traditionally, mathematical models of biofilm processes do not take the contribution of the suspended, non-attached bacteria into

Pressure Effect on the 2NaH+MgB2 Hydrogen Absorption Reaction

The hydrogen absorption mechanism of the 2NaH + MgB2 system has been investigated in detail. Depending on the applied hydrogen pressure, different intermediate phases are observed. In the case of absorption measurements performed under 50 bar of hydrogen pressure, NaBH4 is found not to be formed directly. Instead, first an unknown phase is formed, followed upon further heating by the formation of

Binding and elution behavior of small deoxyribonucleic acid fragments on a strong anion-exchanger multimodal chromatography resin.

The separation behavior of small single-stranded from double-stranded DNA molecules has been determined on a multimodal (mixed-mode) chromatography system. The resin used is a strong anion exchanger which also modulates hydrophobic recognition. The intrinsic differences between single- and double-stranded DNAs concerning charge, hydrophobicity and three-dimensional structure render this form of MM

Solid-to-fluid-like DNA transition in viruses facilitates infection.

Releasing the packaged viral DNA into the host cell is an essential process to initiate viral infection. In many double-stranded DNA bacterial viruses and herpesviruses, the tightly packaged genome is hexagonally ordered and stressed in the protein shell, called the capsid. DNA condensed in this state inside viral capsids has been shown to be trapped in a glassy state, with restricted molecular mo

The effect of tourniquet use on fixation quality in cemented total knee arthroplasty a prospective randomized clinical controlled RSA trial.

A concern that arises with any change in technique is whether it affects the long-term implant stability. The objective of this study was to evaluate the early migration, measured by radiostereometric analysis (RSA), and the functional outcome of the Triathlon™ cemented knee prosthesis, operated on with or without a tourniquet. During the last decades RSA has emerged as a way to assess prosthetic

Spectrally Resolved Maker Fringes in High-Order Harmonic Generation

We investigate macroscopic interference effects in high-order harmonic generation using a Ti:sapphire laser operating at a 100 kHz repetition rate. The structure and behavior of spectral and spatial interference fringes are explained and analytically described by transient phase matching of the long electron trajectory contribution. Time-frequency mapping due to the temporal chirp of the harmonic

Retinol-Binding Protein 4 in Young Men With Low Versus Normal Birth Weight: Physiological Response to Short-Term Overfeeding

Retinol-binding protein 4 (RBP4) is a plasma protein which is elevated in obesity and type 2 diabetes. We aimed to investigate whether RBP4 represents a mechanism underlying the associations between low birth weight (LBW), high-fat diet, and insulin resistance. Forty-six young, lean men with low (n = 20) or normal (n = 26) birth weight underwent a 5-day high-fat high-calorie (HFHC) dietary interve

Visualizing the World. Epistemic Strategies in the History of Scientific Illustrations

The history of scientific illustrations is a story that correspond the cultural, economic, political and scientific history of the world. A look into the history of sciences displays that pictures and illustrations had a decisive role for the sciences progressive success and rising societal status from the sixteenth century. The illustrations visualized the unknown to graspable facts. Without the

From Learning Companions to Testing Companions Experience with a Teachable Agent Motivates Students' Performance on Summative Tests

In three quasi-experimental studies, we investigated the effects of placing a Teachable Agent (TA) from a math game in a digital summative test. We hypothesized that the TA would affect test performance, even without actual "teachability", by social influence on the test situation. In Study 1 (N=47), students did a pretest, played the math game for seven weeks, and did a posttest either with or wi

Simulating forest productivity along a neotropical elevational transect: temperature variation and carbon use efficiency

A better understanding of the mechanisms controlling the magnitude and sign of carbon components in tropical forest ecosystems is important for reliable estimation of this important regional component of the global carbon cycle. We used the JULES vegetation model to simulate all components of the carbon balance at six sites along an Andes-Amazon transect across Peru and Brazil and compared the res