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A comparison of adsorption of organic micropollutants onto activated carbon following chemically enhanced primary treatment with microsieving, direct membrane filtration and tertiary treatment of municipal wastewater

The adsorption of organic micropollutants onto powdered activated carbon (PAC) was investigated in laboratory scale based on samples from four wastewater process streams (matrices); three from a pilot-scale plant with different degrees of physicochemical treatment of municipal wastewater and one from a full-scale activated sludge plant with post-precipitation. The pilot-scale treatment consisted o

Physicochemical Treatment of Municipal Wastewater : From Direct Membrane Filtration to Adsorption of Organic Micropollutants

Populärvetenskaplig sammanfattningAvloppsvatten med läkemedelsrester renas med filter och aktivt kolVA-bolagen står inför flera utmaningar vad gäller rening av avloppsvatten. Till exempel att minska energianvändningen på reningsverken, samt att rena avloppsvattnet från läkemedelsrester. I den här studien har olika typer av filtrering i kombination med aktivt kol testats med målet att rena från läkPharmaceutical residues and other organic micropollutants are transported via municipal wastewater to wastewater treatment plants (WWTPs). However, current treatment processes are not designed to remove organic micropollutants, and several such compounds have been found in recipients, where they can have negative effects on aquatic organisms. Additional processes are therefore required to reduce t

The Clinical Course of Severe Alpha-1-Antitrypsin Deficiency in Patients Identified by Screening

Background: Severe alpha-1-antitrypsin deficiency (AATD) is a genetic condition predisposing to chronic obstructive pulmonary disease (COPD) and liver disease. Its natural course is not well known. Our aim was to study the natural course of AATD by analyzing the clinical course in individuals with severe AATD identified by screening.Materials and Methods: Of the 1585 individuals included in the Sw

5 frågor till Adriana - Maria Hiller

Adriana-Maria Hiller, ST-läkare vid lung- och allergikliniken, Skånes universitetssjukhus, är en av författarna till en artikel om veteberoende ansträngningsutlöst anafylaxi.

Unraveling electronic band structure of narrow-bandgap p-n nanojunctions in heterostructured nanowires

The electronic band structure of complex nanostructured semiconductors has a considerable effect on the final electronic and optical properties of the material and, ultimately, on the functionality of the devices incorporating them. Valence electron energy-loss spectroscopy (VEELS) in the transmission electron microscope (TEM) provides the possibility of measuring this property of semiconductors w

Human-induced arsenic pollution modeling in surface waters : An integrated approach using machine learning algorithms and environmental factors

In recent years, assessment of sediment contamination by heavy metals, i.e., arsenic, has attracted the interest of scientists worldwide. The present study provides a new methodology to better understand the factors influencing surface water vulnerability to arsenic pollution by two advanced machine learning algorithms including boosted regression trees (BRT) and random forest (RF). Based on the s

Symmetry-controlled singlet-triplet transition in a double-barrier quantum ring

We engineer a system of two strongly confined quantum dots to gain reproducible electrostatic control of the even-electron spin at zero magnetic field. Coupling the dots in a tight ring-shaped potential with two tunnel barriers, we demonstrate that an electric field can switch the electron ground state between a singlet and a triplet configuration. Comparing our experimental cotunneling spectrosco

Measuring the properties of semiconductor nanowires with transmission electron microscopy

The extremely small feature size and total sample volume of semiconductor nanowire materials has meant that advanced techniques have been required for even the most routine sample characterization since the structures were first reported. Electron microscopy has been the technique of choice for fast and reliable determination of nanowire morphology, structure, and composition since the earliest re

Size-dependent melting of silica-encapsulated gold nanoparticles

We report on the size dependence of the melting temperature of silica-encapsulated gold nanoparticles. The melting point was determined using differential thermal analysis (DTA) coupled to thermal gravimetric analysis (TGA) techniques. The small gold particles, with sizes ranging from 1.5 to 20 nm, were synthesized using radiolytic and chemical reduction procedures and then coated with porous sili

Bottom-up and top-down drivers of herbivory on Arabica coffee along an environmental and management gradient

While sustainable agriculture relies on natural pest control, we lack insights into the relative importance of bottom-up and top-down factors on pest levels, especially along broad environmental and management gradients. To this aim, we focused on bottom-up and top-down control of herbivore damage in sixty sites in the centre of origin of Arabica coffee in southwestern Ethiopia, where coffee grows

Phonon transport and thermoelectricity in defect-engineered InAs nanowires

There have been reports of improvements in the thermoelectric figure of merit through the use of nanostructured materials to suppress the lattice thermal conductivity. Here, we report on a fundamental study of the combined effects of defect planes and surface scattering on phonon transport and thermoelectric properties of defect-engineered InAs nanowires. A microfabricated device is employed to me

Public preference for sustainable land use policies – Empirical results from multinomial logit model analysis

Public preferences for sustainable land use policy instruments and the motivations behind such preferences are important to make appropriate policies. Based on survey data (n = 309) from northeastern Somalia, we examined preferences for a set of land use policy instruments relative to no policy (i.e. the current status quo) and how cultural worldviews predict such preferences. We used a multinomia

Volcanic temperature changes modulated volatile release and climate fluctuations at the end-Triassic mass extinction

Emplacement of the Central Atlantic Magmatic Province (CAMP) is thought to have triggered global environmental changes and the end-Triassic mass extinction (ETE). However, the mechanisms linking volcanism and environmental change are unclear. Here we provide new insight into these linkages by measuring the abundance of both sedimentary five- to six-ring polycyclic aromatic hydrocarbons (PAHs) and

Early and late-onset syncope : insight into mechanisms

AIMS: Unexplained syncope is an important clinical challenge. The influence of age at first syncope on the final syncope diagnosis is not well studied.METHODS AND RESULTS: Consecutive head-up tilt patients (n = 1928) evaluated for unexplained syncope were stratified into age groups

Multi-scattering software part II : Experimental validation for the light intensity distribution

This article, Part II of an article series on GPU-accelerated Monte Carlo simulation of photon transport through turbid media, focuses on the validation of the online software Multi-Scattering. While Part I detailed the implementation of the computational model, simulated and experimental results are now compared for the distribution of the scattered light intensity. The scattering phantoms prepar

Chaperones mainly suppress primary nucleation during formation of functional amyloid required for bacterial biofilm formation

Unlike misfolding in neurodegenerative diseases, aggregation of functional amyloids involved in bacterial biofilm, e.g. CsgA (E. coli) and FapC (Pseudomonas), is carefully regulated. However, it is unclear whether functional aggregation is inhibited by chaperones targeting pathological misfolding and if so by what mechanism. Here we analyze how four entirely different human chaperones or protein m