Hydrolysis of Brewers' Spent Grain by Carbohydrate Degrading Enzymes

In this work four commercial cellulase‐hemicellulase mixtures with different activity profiles were used for solubilization of carbohydrates from brewers' spent grain (BSG). After the enzyme treatment, both the solubilised fraction and the unhydrolysed residue were characterized. Treatment with 5,000 nkat/g xylanase for 5 h at 50°C resulted in the solubilisation of 13–14% of the BSG dry weight as monosaccharides. This corresponded to the solubilisation of 26–28% of the original carbohydrates and 30–34% of original arabinoxylans, depending on the enzyme cocktail used. The relatively low hydrolysis level indicates that the majority of the BSG biomass is rather recalcitrant towards the cellulose‐hemicellulase enzyme mixtures applied in this study. The enzyme activity profile had a crucial impact on the chemistry of the oligosaccharides produced through the solubilisation of BSG. The presence of feruloyl esterase (FAE) activity in the enzyme cocktail resulted in the production of free ferulic acid, arabinoxylo‐oligosaccharides and their corresponding monomers. However, when the enzyme mixture was devoid of FAE activity, ferulic acid was still bound to the oligosaccharides. The unhydrolysed fraction was still found to contain over 40% of carbohydrates after enzymatic treatment despite the extensive enzyme dosages used. The protein fraction remained largely unaffected (i.e. insoluble) by the carbohydrate‐disrupting enzyme treatments. In addition to the recalcitrant carbohydrates, the residue was enriched with lignin and lipid type structures.     

Cross-linking of tyrosine-containing peptides by hydrogen peroxide-activated <Emphasis Type="Italic">Coprinus Cinereus</Emphasis> peroxidase

Hydrogen peroxide-activated Coprinus Cinereus peroxidase (CIP) can initiate polymerization of tyrosine-containing peptides via initial formation of an intermediate tyrosyl radical, which for the first time has been identified by spin trap electron spin resonance spectroscopy as located on carbon 1 in the aromatic ring, and subsequent formation of either dityrosine or isodityrosine bonds through a net elimination of two hydrogen atoms between peptides. The rate and degree of polymerization were found to depend on peptide size and the amino acid adjacent to tyrosine, as longer peptides and amino acids with bulky side groups were less reactive. In the forwarded hypothesis for the reaction mechanism upon peroxidase-initiated cross-linking of tyrosine-containing peptides and proteins, it is suggested that the polymerization takes place through a radical chain reaction. The polymerization reaction shows the potential of CIP as a protein structure-engineering tool to control functionality of proteinious food matrices or in biopolymer formation.     

Maternal representations of past and current attachment relationships, and emotional experience across the transition to motherhood: A longitudinal study.

Sad and anxious feelings are known to increase in the immediate postpartum period, whereas studies on new mothers' other emotional qualities such as anger are scarce. In laboratory studies, attachment security was found to be associated with effective emotion regulation in challenging situations. This study investigated attachment representations of experiences with parents and of current experiences with the partner as predictors of sad, anxious, and angry feelings across the transition to motherhood. Seventy-seven pregnant women in their third trimester were administered the Adult Attachment Interview and the Current Relationship Interview. The Differential Emotions Scale was given in pregnancy and at the infant's ages of 2 weeks, 2, 4, and 6 months, asking both mothers and fathers about maternal emotional experience. Sadness and anxiety increased 2 weeks postpartum and returned to below baseline over the following months, while anger did not change. Contrary to mothers with an insecure representation of their couple relationship, those with a secure representation reported and displayed increased sadness and anxiety 2 weeks after giving birth, from which they quickly recovered. For mothers secure in their representation of past attachment relationships with parents, an increase of low-level anger emerged 4 months postpartum, which did not occur in insecure participants and receded quickly. It can be concluded that secure representations of current and past attachment relationships help new mothers express and recover from negative emotions. These findings further elucidate the associations between attachment status and emotion regulation while adding a couple perspective. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Highly Customizable Bone Fracture Fixation through the Marriage of Composites and Screws

Open reduction internal fixation (ORIF) metal plates provide exceptional support for unstable bone fractures; however, they often result in debilitating soft-tissue adhesions and their rigid shape cannot be easily customized by surgeons. In this work, a surgically feasible ORIF methodology, called AdhFix, is developed by combining screws with polymer/hydroxyapatite composites, which are applied and shaped in situ before being rapidly cured on demand via high-energy visible-light-induced thiol–ene coupling chemistry. The method is developed on porcine metacarpals with transverse and multifragmented fractures, resulting in strong and stable fixations with a bending rigidity of 0.28 (0.03) N m² and a maximum load before break of 220 (15) N. Evaluations on human cadaver hands with proximal phalanx fractures show that AdhFix withstands the forces from finger flexing exercises, while short- and long-term in vivo rat femur fracture models show that AdhFix successfully supports bone healing without degradation, adverse effects, or soft-tissue adhesions. This procedure represents a radical new approach to fracture fixation, which grants surgeons unparalleled customizability and does not result in soft-tissue adhesions.     

Schubtragfähigkeit von Wänden aus Kalksand‐Planelementen mit geringem Überbindemaß — Experiment und rechnerische Simulation

Der Querkraftwiderstand V_R von Mauerwerkswänden, die in ihrer Ebene durch Wind‐ oder Erdbebeneinwirkungen beansprucht werden, hängt auch vom Überbindemaß ü bzw. vom Verhältnis des Überbindemaßes zur Steinhöhe ü/h_st ab. Das nach Norm derzeit zulässige Überbindemaß von ü ≥ 0,4 h_st kann bei der Verwendung von Planelementen in der Praxis nicht immer eingehalten werden. Für diese Fälle ist in den allgemeinen bauaufsichtlichen Zulassungen (abZ) des Deutschen Instituts für Bautechnik (DIBt) für Kalksand‐Planelemente im Bereich 0,4 > ü ≥ 0,2 h_st bzw. 12,5 cm bisher ein verminderter zulässiger Rechenwert der charakteristischen Schubfestigkeit f_vk von 60 % des Wertes nach DIN 1053‐100:2007‐09 (ü ≥ 0,4 h_st ) anzuwenden. Diese, auf Ergebnissen alter Versuche mit überholten Prüfanordnungen beruhenden, hohen Tragfähigkeitseinbußen waren im Zuge der Aufnahme von Planelementen in die Bemessungsnormen für Mauerwerk mit neuem Schubbemessungskonzept zu überprüfen. Daher wurden umfangreiche experimentelle und theoretische Untersuchungen an 17,5 cm dicken, 2,50 m hohen Schubwänden aus Kalksand‐Planelementmauerwerk mit Dünnbettmörtel und unvermörtelten Stoßfugen durchgeführt. Ziel war es, den Einfluss geringer Überbindemaße ü/h_st < 0,4 auf die Schubtragfähigkeit dieser Wände, insbesondere bei statisch‐zyklischen Horizontalverformungen in Wandebene, quantitativ zu bestimmen. Als Versuchsparameter wurden die Wandauflast (σ = 0,5/1,0/1,43 N/mm²), das Überbindemaß (ü/h_st = 0,2/0,4) und die Einspannung am Wandkopf und ‐fuß variiert. Die Untersuchungen ergaben im Bereich der normativ bemessungs relevanten geringen Überbindemaße 0,2 ″ ü/h_st ″ 0,4 keine signifikanten Traglasteinbußen. Bei erweiterten theoretischen FE‐Analysen für das baupraktisch übliche Spektrum vorhandener Überbindemaße 0,2 ″ ü/h_st ″ 1,0 von Wänden mit Auflastspannungen von 0,5 N/mm² bzw. 1,0 N/mm² wurde eine Traglastminderung von maximal 12 bis 16 % berechnet. Der Abtrag der Horizontallast vom Wandkopf zum Wandfuß erfolgt über ein schräges Druckspannungsfeld. Im Überbindebereich der Elemente auftretende Spannungskonzentrationen können zu örtlich begrenzten Rissbildungen führen, ohne dass die Tragfähigkeit der Wand hierdurch beeinträchtigt wird. Diese ist erst dann erschöpft, wenn insbesondere am Wandfuß die vom gerissenen Mauerwerk übertragbaren, schrägen Druckspannungen nicht mehr aufgenommen werden können. Shear load bearing capacity of masonry walls made of calcium silicate element units with a low overlap length — Experimental and numerical simulation analysis. The shear force resistance capacity V_R of masonry walls subjected, in their plane, to loads from winds or earthquakes, amongst other things, depends on the overlap length of the units ü or on the ratio of the overlap length and the height of the unit ü/h_st . The currently permissible overlap length, according to German design standards and norms, of ü ≥ 0.4 h_st can not always be adhered to in building practice, when using element units. In such cases and according to general technical approval code (abZ) of the German Institute for Building Technology (DIBt) for calcium silicate element units within the range 0.4 > ü ≥ 0.2 h_st or 12.5 cm, a reduced permissible calculation value of the characteristic shear strength f_vk of 60 % of the value according to DIN 1053‐100:2007‐09 (ü ≥ 0.4 h_st ) has been used to date. This high loss of load bearing capacity, based on results of older experiments with ob solete test setups, was to be tested in the course of the inclusion of element units in the calculation standards for masonry walls, with a new shear calculation concept. As a result, extensive experimental and theoretical tests were carried out on 17.5 cm thick and 2.50 m high shear walls made of masonry calcium silicate element units and ungrouted butt joints. The objective was to quantatively determine the influence of low overlap length ü/h_st < 0.4 on the shear resistance of these masonry walls and in particular with static‐cyclical horizontal displacement at the wall top. The vertical load pressure (σ = 0.5/1.0/1.43 N/mm²), the overlap length (ü/h_st = 0.2/0.4) and the fixing at the top and bottom of the wall were varied and used as experimental parameters. Within the range of normative calculation with low overlap lengths 0.2 ″ ü/h_st ″ 0.4, the investigations showed no significant load bearing capacity loss. With more extensive theoretical Finite Element analyses for the normal building practice spectrum of overlap lengths 0.2 ″ ü/h_st ″ 1.0 for walls with a vertical load of 0.5 N/mm² or 1.0 N/mm², a reduction of load bearing capacity of maximum 12 % to 16 % was calculated. The transmission of the horizontal shear load from the top of the wall to the bottom of the wall takes place through a diagonal compression stress field. Cracks may occur in the overlap area of the element units as a result of stress concentration, which are limited to the overlap area and do not cause any impairment to the load bearing capacity of the wall. This capacity is only then exhausted when the trans missible, diagonal compression stress can no longer be absorbed, especially at the bottom of the wall with cracked masonry.     

An h index for Mendeley: comparison of citation-based h indices and a readership-based hmen index for 29 authors

Scientometrics - As Mendeley readership counts seems to be the most closely related to citation counts in comparison to other altmetrics, this paper proposes the hmen index as a variant of the...     

Replacing human-edible feed ingredients with by-products increases net food production efficiency in dairy cows

Global demand for food is increasing, and use of large amounts of potentially human-edible feedstuffs for dairy cows is an important concern. The present study examined whether feeding a by-product-based concentrate combined with high-quality grass silage to high-producing dairy cows affected feed intake and milk production compared with a conventional diet, as well as the effect on efficiency of human food production. In a changeover experiment with four 21-d periods, 24 dairy cows in mid-lactation were offered 9.6 kg of dry matter per day with 1 of 4 concentrates and high-quality grass silage ad libitum. The control concentrate was based on cereal grain (wheat, oat, and barley) and soybean meal, whereas the 3 by-product-based concentrates contained sugar beet pulp in combination with mainly heat-treated rapeseed meal, distillers grain, or a mixture of both. All diets were formulated to be isoenergetic and isonitrogenous. The cows had 10-fold higher starch intake when fed the control diet than when fed the by-product-based concentrates. Silage intake (13 kg of dry matter/d) and milk production (33 kg of energy-corrected milk/d) were not affected by the change in diet. Therefore, replacing cereals and soybean meal with human-inedible by-products in a high-quality forage diet to dairy cows increased net food protein production substantially without lowering milk production.     

Is dry soil planting an adaptation strategy for maize cultivation in semi-arid Tanzania?

Agriculture has the greatest potential to lift the African continent out of poverty and alleviate hunger. Among the countries in sub-Saharan Africa, Tanzania has an abundance of natural resources and major agricultural potential. However, one of the most important constraints facing Tanzania’s agricultural sector is the dependence on unreliable and irregular weather, including rainfall. A strategy to cope with climate uncertainty in semi-arid regions is to proceed with the sowing of the crop before the onset of the rainy season. The advantage is that when the rains start, seeds are already in the soil and can begin immediately the process of germination. The objective of this paper was to assess the effectiveness of dry-soil planting for maize as an adaptation strategy in the context of a changing climate in Dodoma, a semi-arid region in Tanzania. For this assessment, the DSSAT crop model was used in combination with climate scenarios based on representative concentration pathways. A probability of crop failure of more than 80% can be expected when sowing occurs during the planting window (of 21 days) starting on 1st November. The next planting window we assessed, starting on 23rd November (which was still before the onset of rain), presented significantly lower probabilities of crop failure, indicating that sowing before the onset of the rainy season is a suitable adaptation strategy. Results also indicated that, despite not reaching the highest maize grain yields, fields prepared for dry-soil planting still produced adequate yields. The cultivation of several fields using the dry planting method is a strategy farmers can use to cope with low rainfall conditions, since it increases the chances of harvesting at least some of the cultivated fields. We conclude that dry-soil planting is a feasible and valid technique, even in scenarios of climate change, in order to provide acceptable maize yields in semi-arid Tanzania.