Amyloid-intercalated graphene oxide membranes for enhanced nanofiltration

We report on fast pressure-driven nanofiltration of strong GO membranes intercalated by protein amyloid fibrils. We investigate the effect of protein amyloid fibril loading on membrane properties including the membrane stability, microstructure, reflux rate, permeance, rejection rate and fouling resistance. With increasing amyloid fibrils, the membrane becomes smooth and resilient and can be reused for many times with little disintegration. Microstructure analysis shows that amyloid fibrils enable expansion of the interlayer spacing between GO sheets, leading to around 100% increase in average water permeance of the 100 nm thick membrane (15.6 L⋅m−2⋅hr−1⋅bar−1) compared to the neat GO membrane (8.8 L⋅m−2⋅hr−1⋅bar−1). The hybrid membranes display improved moderate ion rejection (44–51%) of heavy metal salts and high molecular rejection (>97%) of organic dyes. Antifouling performance is evaluated in terms of flux recovery ratio and fouling ratios. The incorporation of amyloid fibrils enable GO membranes to change from irreversible fouling to reversible fouling and the hybrid membrane exhibits significantly enhanced flux recovery (>95%). A possible nanofiltration mechanism is proposed to explain the observations

School Surveillance, Control, and Resistance in the United Kingdom

This chapter outlines the development of the current socio-political context within which U.K. schools experience surveillance and implement their security and disciplinary procedures. Schools are suggested to have developed their approaches to social control against a background of neoliberalism and audit culture. This involves the marketisation of much of the school system through an ‘academisation’ process; linked to this is an increased surveillance of teachers and students through datafication, CCTV and other digital means. Another form of surveillance- biopolitical control in schools- shows itself through the traditionalisation of gendered school uniform and the increasing pathologisation of the behaviour of ethnic minorities

A new family for the enigmatic sea pen genus Gyrophyllum Studer, 1891 (Octocorallia, Pennatulacea), a molecular and morphological approach

The description in 1891 of the sea pen genus Gyrophyllum Studer, 1891 and also the type species G. hirondellei Studer, 1891 was based on a single colony collected in the Azores Archipelago. During the 19th and 20th centuries, the family placement of this genus became controversial as the set of morphological features present in Gyrophyllum could justify its assignation to both the families Pennatulidae Ehrenberg, 1834 and Pteroeididae Kölliker, 1880. Deliberations over this intermediate set of characters finally ended in the reunification of the genera and species of both families under Pennatulidae by principle of priority. The use of molecular sources of information based on a series of sequencing techniques presents a different but promising phylogenetic scenario in order to go further in the understanding of pennatulacean systematics. In this paper, a complementary morphological and molecular study (multiloci sequences with three mitochondrial and one nuclear markers) based mainly on newly collected material is carried out. This study re-confirms from a molecular point of view previously published results that indicate the position of Gyrophyllum as being distant from Pennatula Linnaeus, 1758 and Pteroeides Herklots, 1858 (type genera of the families Pennatulidae and Pteroeididae, respectively). This fact together with the results of a detailed morphological examination strongly supports the placement of the enigmatic genus Gyrophyllum in a separate family: Gyrophyllidae fam. nov. and resolves the nomenclatural uncertainty at family level for this genus. Moreover, the characters previously considered useful in the distinction of the two currently recognised species G. hirondellei in the Atlantic and G. sibogae Hickson, 1916 in the Indo-western Pacific are revisited

The effect of catalyst modification on the conversion of glycerol to allyl alcohol

Conversion of glycerol to allyl alcohol was carried out over an iron on alumina catalyst. With the aim of enhancing selectivity towards the desired product and to reduce acrolein formation (a detrimental impurity in the subsequent epoxidation of allyl alcohol) the supported iron catalyst was modified using alkali metals. It was found that lithium, sodium, potassium, rubidium and caesium deposition on the catalyst surface increased allyl alcohol yield and reduced the rate of catalyst deactivation. Coincidently, acrolein selectivity decreased by up to 75% following treatment with the alkali salt.Changes in the product distribution were determined to be associated with altering the acid/base properties of the catalyst, as confirmed by isopropanol dehydration/dehydrogenation, ammonia and carbon dioxide temperature programmed desorption. The treatment was also found to influence the physical properties of the catalyst surface. A correlation between acid to basic site concentration and allyl alcohol selectivity was established. A reduction in the former value results in an enhancement in the rate of allyl alcohol formation. A reaction mechanism was developed based on the effect of iron and alkali metals catalysing the conversion of glycerol into allyl alcohol. The proposed catalyst modification technique is a straightforward method, readily applicable at a larger scale due to the simplicity of the alkali inclusion and its striking influence on the reaction selectivity

Detection of charged particles and x-rays by scintillator layers coupled to amorphous silicon photodiode arrays

Hydrogenated amorphous silicon (a-Si:H) p-i-n diodes with transparent metallic contacts are shown to be suitable for detecting charged particles, electrons, and X-rays. When coupled to a suitable scintillator using CsI(Tl) as the scintillator we show a capability to detect minimum ionizing particles with S/N {approximately}20. We demonstrate such an arrangement by operating a p-i-n diode in photovoltaic mode (reverse bias). Moreover, we show that a p-i-n diode can also work as a photoconductor under forward bias and produces a gain yield of 3-8 higher light sensitivity for shaping times of 1 {mu}s. n-i-n devices have similar optical gain as the p-i-n photoconductor for short integrating times ( < 10{mu}s). However, n-i-n devices exhibit much higher gain for a long term integration (10ms) than the p-i-n ones. High sensitivity photosensors are very desirable for X-ray medical imaging because radiation exposure dose can be reduced significantly. The scintillator CsI layers we made have higher spatial resolution than the Kodak commercial scintillator screens due to their internal columnar structure which can collimate the scintillation light. Evaporated CsI layers are shown to be more resistant to radiation damage than the crystalline bulk CsI(Tl)