Rejection Behavior Research Articles

Edible insect consumption and Turkish consumers’ attitudes towards entomophagy

Generally, in the world edible insects have gained popularity and awareness among people. Therefore, the study on Turkish consumers' attitudes and consumption towards entomophagy has important findings. The relationships edible insects with sociodemographic effects, demand to eat and personality traits of participants were determined by online questionnaire method. According to the results, most of the participants have not consumed edible insects before and furthermore both male and female consumers were not found to be positive tendency for eating edible insects. The main factors of rejection behaviors are disgusting, food neophobia and some health and religious concerns. However, a few participants have already consumed edible insects and have mainly exhibited this experience in abroad. Thereby, the study suggests that familiarity and awareness are the most significant factors changing attitudes towards to edible insect consumption for Turkish consumers. To determine consumption behavior and preferences of Turkish consumers, the most significant factors are overpassing the psychological barrier such as neophobia and facilitate entomophagy acceptance. This study could enable the development of strategies to increase desire of eating EI (edible insects) by Turkish consumers and promote insect production.

Reproductive Isolation in the Cryptic Species Complex of a Key Pest: Analysis of Mating and Rejection Behaviour of Onion Thrips (Thrips tabaci Lindeman).

Simple SummaryThe onion thrips (Thrips tabaci), which is a key pest worldwide, includes three characteristic, distinct groups (i.e., lineages) under the same species name. In the current report, we addressed the question of whether individuals from these lineages recognize and assess each other as potential mating partners. We demonstrated that at least two of these lineages do not belong to the same species, since under our laboratory conditions no mating occurred between them. Moreover, specimens from these cross pairings often exhibited an escape response upon contact with the other thrips, while most of the pairs from the same lineages readily mated at their first interaction. The behaviour of males clearly indicated that they can assess the mating status of a female and usually only try to copulate with virgins. Our findings are important not only because in agriculture it is vital to know whether morphologically similar entities belong to the same species, but also because knowledge about the communication of insects and the possible role of the cues involved can help the development of new plant protection techniques.Thrips tabaci Lindeman is a serious pest of various cultivated plants, with three, distinct lineages within a cryptic species complex. Despite the well-known significance of this pest, many attributes of these lineages are not yet fully understood, including their reproductive behaviour. We performed no-choice-design cross-mating experiments under a controlled laboratory environment with virgin adult individuals from all three lineages. The behaviour of thrips was recorded with a camera mounted on a stereomicroscope, and the recordings were analysed in detail. We found that the so-called leek-associated lineages of this cryptic species complex are reproductively isolated from the tobacco-associated lineage; therefore, they represent different species. Divergence in the behaviour of conspecific and heterospecific pairs became evident only after contact. There were no marked differences between the lineages in their precopulatory and copulatory behaviour, except in the duration of the latter. We confirmed mating between thelytokous females and arrhenotokous males; however, we assume some form of loss of function in the sexual traits of asexual females. The post-mating behaviour of males indicated the presence and role of an anti-aphrodisiac pheromone. We also demonstrated differences between lineages regarding their activity and their propensity for exhibiting an escape response upon interaction with heterospecific thrips.

If at first you don't adopt - Investigating determinants of new product leapfrogging behavior

In times of rapid technological advancements, consumers often reject new products as they intentionally postpone their adoption until significant technology improvements are available. This phenomenon is commonly called consumer leapfrogging behavior. While previous studies have found vast empirical evidence for the occurrence and detrimental effects of such behavior, only a few studies have focused on investigating the nature and determinants of consumer leapfrogging. Hence, this article systematically explores and empirically validates potential determinants of consumer leapfrogging behavior by applying a multimethod approach. First, we conducted a systematic literature review to summarize the current research. Second, we applied a qualitative study to identify potential reasons for consumer leapfrogging behavior. The results show that known theoretical rationales for innovation rejection behavior tied to active and passive innovation resistance do not comprehensively account for the complex psychological processes of this behavior. Consequently, we introduce a new construct called “leap disposition” to explain consumers’ disposition to reject a new product and instead wait for a superior subsequent product generation. Third, we empirically validate and quantify the relative importance of both established constructs (i.e., active and passive innovation resistance), as well as the newly introduced leap disposition, for leapfrogging behavior within a large-scale study.

Rejection of Conspecific Eggs Associated with the Appearance of Eggs, in the Azure-Winged Magpie Cyanopica cyanus in Korea

Avian brood parasitism is a reproductive strategy in which a parasitic species lays its eggs in the nests of a host. In response to parasitism, hosts have evolved various defence strategies. One of the host defences against intraspecific and interspecific brood parasitism is to distinguish parasitic eggs based on intraclutch variation in egg appearance. Hosts can improve their ability to discriminate parasitic eggs by lowering the degree of their intraclutch variation in egg appearance. Therefore, intraclutch variation may affect the egg rejection behaviour of hosts. In this study, we conducted experiments to study egg recognition and rejection behavior for mimetic eggs in Azure-winged Magpies Cyanopica cyanus in Korea. We also investigated the level of variation in egg appearance (egg color, spottiness and volume) in order to explore whether the degree of this variation is associated with the rejection decision. We found that there were no differences in egg coloration or spottiness between the rejecter and accepter. However, we found that intraclutch egg volume variation in rejecters was significantly lower than that in accepters, indicating that the Azure-winged Magpie is likely to recognize its own eggs by lowering its intraclutch variation in egg volume as a defensive strategy against brood parasitism. This study suggests that the Azure-winged Magpie use not the differences in egg coloration but egg volume to discriminate and reject closely mimetic conspecific eggs.

Decision-making dynamic evolution among groups regarding express packaging waste recycling under different reference dependence and information policy.

The reveal of express packaging waste recycling behavior evolution trend is crucial to waste management. Current models are mostly based on the classic expected utility theory, without considering groups are susceptible to internal and external factors. To address this drawback, we construct an evolutionary game model of express packaging waste recycling behavior by considering information policy and reference dependence factors to explore groups' decision-making with different initial adoption rates. A system dynamics simulation model based on survey data is then built, and simulation experiments are also designed to reveal the impacts of key factors on the evolution path of recycling behavior. The results show that, without information policy, groups cyclically oscillate around the initial state. The stable trend depends on the information intensity, and the information effect is marginal diminishing. Groups with a lower initial adoption rate will evolve to an ideal stable strategy only when information intensity exceeds the threshold of ten. Reference points can change behavior strategies and are characterized by significant loss aversion. The benefits and costs affect groups' adoption or rejection behaviors. These findings can provide new ideas for related research and offer a reference for the government to formulate efficient waste management policies.

Fabrication and modification of PVDF/PSF hollow-fiber membranes for ginseng extract and saline water separations via direct contact membrane distillation

Poly(vinylidene fluoride) (PVDF)/polysulfone (PSF) hollow-fiber (HF) membranes with high mechanical strength and satisfactory water permeance using a green fabrication technique were investigated by varying the compositions of coating fluid and bore fluid during membrane spinning using a triple spinneret. The results demonstrated that the HF membranes using hydrophobic coating fluid provided a skinless structure with higher water permeance than those produced from a hydrophilic coating fluid or polymer solution. These skinless PVDF/PSF membranes showed 99.96% rejection of a ginseng extract solution with different concentrations via direct contact membrane distillation (DCMD) but relatively poor stability and rejection behavior for saline water due to the poor hydrophobicity of the membrane. To improve the hydrophobic properties of PVDF/PSF membranes for saline water, two hydrophobic modification methods (i.e., chemical modification and physical modification) were employed and compared. Modified membranes showed enhanced hydrophobic properties as characterized by XPS, FTIR analysis, and stability tests. In the separation of saline water (35 g/L salts and 0.1 mM sodium dodecyl sulfate), modified membranes showed higher water flux and rejection than pristine membrane. The modified membrane showed greater than 99.99% rejection and outstanding stability even after operation for 120 h. This work provides skinless fiber-aligned PVDF/PSF hollow-fiber membranes with different surface properties for diverse systems via DCMD, such as concentration of food extract or separation of saline water. • Fiber-aligned PVDF/PSF HF membranes were comprehensively studied. • Two hydrophobic modification methods for these membranes were compared for DCMD. • These skinless PVDF/PSF HF membranes show 99.96% rejection for ginseng extracts via DCMD. • Modified membranes show excellent stability and 99.99% rejection for saline water.

Elucidation of physicochemical scaling mechanisms in membrane distillation (MD): Implication to the control of inorganic fouling

This study elucidates the physicochemical mechanisms of monovalent and multivalent inorganic scaling and suggests an optimal cleaning strategy for efficient membrane distillation (MD) operation. Three distinct stages of MD inorganic scaling were clearly identified by i) experimentally measuring transient flux, ii) rejection behavior resulted from the deposition of a scale, and iii) SEM-EDX analysis of the membrane. During stage 1, no scale was found over the membrane surface showing almost stable water flux and permeate conductivity. In stage 2, the onset of inorganic scaling resulted in the deposition of scaling on some parts of the membrane surface, partially covering the membrane pores, which lead to a sudden reduction in the water flux despite a steady solute rejection. However, as scaling expands into the pore in final stage 3, the permeate conductivity increased, indicating a reduction in rejection. Then, the pores were completely blocked, and the water flux reached almost zero. To simulate this scaling formation more fundamentally, the saturation index (SI) and supersaturation (S) concepts were introduced. The type and timing of scaling were successfully predicted by the SI value, and the amount of scaling was accurately estimated by the S value. Moreover, through the analysis of this physicochemical mechanism of inorganic scaling, an optimal cleaning strategy for sustainable MD operation was proposed.

The Effects of a Male Audience on Male and Female Mating Behaviour in the Blood-Sucking Bug Rhodnius prolixus

Social context is a key factor affecting sexual behaviour and cannot be neglected in gregarious species, such as triatomine blood-sucking bugs. Here we study the influence of the social context on the sexual reproductive behaviour of males and females of Rhodnius prolixus Stål. Specifically, we identify and compare the frequencies and sequence of sexual behaviours exhibited by a focal pair in presence or absence of a male audience. We expect that in presence of a male audience females increase their selectiveness level since the risk of losing infertile eggs decreases in presence of more candidates and females can benefit from copulating with a better quality male. Besides, in presence of potential rivals, we expect changes in the sexual behaviour of focal males, associated to a reduction in the risk of sperm competition. As expected, in presence of a male audience, females significantly increased the exhibition of rejection behaviour. Moreover, focal males exhibited shorter latencies to mount the female, longer duration of copula, and differences in their stereotyped behaviour exhibited during copula. We discuss the influence of the social context on the reproductive behaviour of females and males of R. prolixus.

Separation of single and mixed anionic dyes in saline solutions using uncharged polyacrylonitrile-tris(hydroxymethyl)aminomethane (PAN-Tris) ultrafiltration membrane: Performance and mechanism

Separation of single or mixed dyes in saline solutions can recover valuable chemicals from dye-containing wastewater. Application of ultrafiltration (UF) in this area is limited by the performance of traditional UF membranes and remains a challenge to achieve high efficacy. Herein, three uncharged polyacrylonitrile-tris(hydroxymethyl)aminomethane (PAN-Tris) UF membranes were adopted for anionic dye separation in saline solutions. These membranes were prepared via in situ modification and characterized by XPS, 1H NMR spectroscopy, contact angle, permeation, mechanical properties, etc. Congo red (CR), methyl blue (MB), and methyl orange (MO) were chosen as model dyes with different sizes and valences. The as-prepared PAN-Tris membranes possessed mean pore sizes ranging from 8.14 to 10.98 nm, but with strong negative zeta potential ranging from −12 to −43 mV at pH 7. Thus, they rejected above 98% CR (with large molecular size) and MB (with high valence), and fractionated the mixtures of CR or MB with MO (with monovalence) in water solutions. The maximum flux of a dye solution reached about 85 L⋅m−2⋅h−1 at 1 bar. Subsequently, the influences of operating pressure, dye concentration, pH value, salt type (NaCl, Na2SO4, MgCl2, or MgSO4) and salt concentration (1000, 5000, or 10000 ppm) on the dye separation property of the membranes were investigated. The results showed that dye rejection behavior depends on the molecular size and valence of dye, as well as membrane property. Thereafter, the electric double layer (EDL) model and the static permeation analysis were combined to investigate the separation mechanism through the changes of the electrostatic effects and effective pore sizes of the membranes in saline solutions. Guided by the revealed mechanism, the MB/CR mixture was successfully separated by using a NaCl solution (≥5000 ppm) for the first time. Overall, this study not only demonstrates that novel UF membranes hold promise for highly effective treatments of dye-containing wastewater, and but also provides an insightful understanding of the dye rejection mechanism that can guide the rational design of UF membranes.

Intrinsic Dependence of Groundwater Cation Hydraulic and Concentration Features on Negatively Charged Thin Composite Nanofiltration Membrane Rejection and Permeation Behavior.

Commercial nanofiltration membranes of different molecular weight cut-offs were tested on a pilot plant for the exploration of permeation nature of Ca, Mg, Mn, Fe, Na and ammonium ions. Correlation of transmembrane pressure and rejection quotient versus volumetric flux efficiency on nanofiltration membrane rejection and permeability behavior toward hydrated divalent and monovalent ions separation from the natural groundwater was observed. Membrane ion rejection affinity (MIRA) dimension was established as normalized TMP with regard to permeate solute moiety representing pressure value necessary for solute rejection change of 1%. Ion rejection coefficient (IRC) was introduced to evaluate the membrane rejection capability, and to indicate the prevailed nanofiltration partitioning mechanism near the membrane surface. Positive values of the IRC indicated satisfactory rejection efficiency of the membrane process and its negative values ensigned very low rejection affinity and high permeability of the membranes for the individual solutes. The TMP quotient and the efficiency of rejection for individual cations showed upward and downward trends along with flux utilization increase. Nanofiltration process was observed as an equilibrium. The higher the Gibbs free energy was, cation rejection was more exothermic and valuably enlarged. Low Gibbs free energy values circumferentially closer to endothermic zone indicated expressed ions permeation.

Horses\u2019 rejection behaviour towards the presence of Senecio jacobaea L. in hay

BackgroundSenecio jacobaea contains pyrrolizidine alkaloids that can induce severe hepatic intoxication in horses, either acute when ingested in high amounts or chronic when consumed over a long period. The aim of this study was to determine horses’ rejection behaviour towards the presence of Senecio jacobaea in hay when fed ad libitum. We hypothesized that adult horses can sort Senecio jacobaea out of the contaminated hay when hay is fed ad libitum. Six warmblood geldings with a mean (±SD) age of 15 ± 2 years were included. In a randomized study, Senecio jacobaea contaminated hay (5% or 10% contamination level) was provided at several timepoints over the day for 1 hour to six. Hay was provided ad libitum for the rest of the day. The horses’ rejection behaviour towards Senecio jacobaea was observed. If a horse ingested two Senecio jacobaea plants twice at different timepoints, then the horse was excluded from the experiment.ResultsTwo out of six horses had to be excluded from the study after three out of 12 observation periods due to repeated Senecio jacobaea intake. Two other horses had to be excluded after nine and 11 out of 12 observation periods. Only two horses were able to sort out the various amounts (5 and 10% contamination level) of Senecio jacobaea during the whole experiment.ConclusionsHorses’ intake of Senecio jacobaea cannot be avoided despite being fed with hay ad libitum. Due to the risk of chronic intoxication by pyrrolizidine alkaloids intake, feeding Senecio jacobaea contaminated hay must be avoided, and pastures with Senecio jacobaea growth are considered inappropriate for feed production.

Light matters: Nest illumination alters egg rejection behavior in a cavity-nesting bird

Egg discrimination by cavity-nesting birds that build nests under dim light conditions was presumed to depend on nest luminance, although this hypothesis has rarely been tested. Tests of egg discrimination ability by cavity-nesting tits under dim light conditions may reveal the selection pressure from brood parasitism that they encounter under natural interactions. We manipulated the intensity of luminance of nests of the Green-backed Tit (Parus monticolus), a potential cuckoo host that possesses a strong discrimination ability of non-mimetic foreign eggs. We performed experiments to test their egg discrimination ability under different light conditions. Our results showed that Green-backed Tits discriminate against non-mimetic foreign eggs under normal light conditions in nest boxes, and this ability persisted at nest luminance as low as 4.78 ​± ​1.31 lux that is several times lower than normal luminance (38.11 ​± ​24.02 lux). However, egg discrimination by Green-backed Tits disappeared when nest luminance was reduced to a minimum of 0.35 ​± ​0.15 lux. The latter value represents total darkness for humans. The present study shows that nest luminance plays a key role in egg discrimination by Green-backed Tits that build nests under dim light conditions. This study provides strong experimental evidence for nest illumination altering egg rejection behavior in cavity-nesting birds.

ANALYSIS OF COURTSHIP BEHAVIOR AS A PARAMETER OF TOXICITY OF ETHYL METHANESULFONATE (EMS) IN DROSOPHILA MELANOGASTER

An anti-cancerous drug and a monofunctional alkylating agent, Ethyl methanesulfonate (EMS), was tested for its toxic effects by using courtship behavioral elements as the parameter in Drosophila melanogaster. EMS concentrations ranging from 0.5 to 15mM were employed by larval feeding technique to analyze the effect. When the different combinations of crosses were performed, the results have revealed that there were no qualitative differences between the control and treated groups. However, quantitatively, it has shown that male courtship elements such as orientation, tapping, wing vibration and licking were significantly prolonged compared to controls. Similar results were observed in case of female rejection behavior elements namely: ignoring, extruding and decamping. On par with this, even the courtship latency and copulation latency were significantly increased and contrary to these, copulation duration was significantly decreased, thus suggesting that the treated males were less vigor; treated females were less receptive on one hand and on the other lower reproductive fitness. Drastic effects of EMS on mating behavior prove that this can be utilized as a parameter for assessing the toxic effects of chemicals.

An In Situ Incorporation of Acrylic Acid and ZnO Nanoparticles into Polyamide Thin Film Composite Membranes for Their Effect on Membrane pH Responsive Behavior.

This paper focuses on an in situ interfacial polymerization modification of polyamide thin film composite membranes with acrylic acid (AA) and zinc oxide (ZnO) nanoparticles. Consequent to this modification, the modified polyamide thin film composite (PA–TFC) membranes exhibited enhanced water permeability and Pb (II) heavy metal rejection. For example, the 0.50:1.50% ZnO/AA modified membranes showed water permeability of 29.85 ± 0.06 L·m−2·h−1·kPa−1 (pH 3), 4.16 ± 0.39 L·m−2·h−1·kPa−1 (pH 7), and 2.80 ± 0.21 L·m−2·h−1·kPa−1 1 (pH 11). This demonstrated enhanced pH responsive properties, and improved water permeability properties against unmodified membranes (2.29 ± 0.59 L·m−2·h−1·kPa−1, 1.79 ± 0.27 L·m−2·h−1·kPa−1, and 0.90 ± 0.21 L·m−2·h−1·kPa−1, respectively). Furthermore, the rejection of Pb (II) ions by the modified PA–TFC membranes was found to be 16.11 ± 0.12% (pH 3), 30.58 ± 0.33% (pH 7), and 96.67 ± 0.09% (pH 11). Additionally, the membranes modified with AA and ZnO/AA demonstrated a significant pH responsiveness compared to membranes modified with only ZnO nanoparticles and unmodified membranes. As such, this demonstrated the swelling behavior due to the inherent “gate effect” of the modified membranes. This was illustrated by the rejection and water permeation behavior, hydrophilic properties, and ion exchange capacity of the modified membranes. The pH responsiveness for the modified membranes was due to the –COOH and –OH functional groups introduced by the AA hydrogel and ZnO nanoparticles.

Rejection behaviour of horses for hay contaminated with meadow saffron (Colchicum autumnale L.).

Extensively used grasslands are frequently utilised for hay production for equines. Especially, extensive meadows have a great variety of plant species, which may include plants that are poisonous for equines such as meadow saffron (Colchicum autumnale L.). To authors' knowledge investigations about horses` avoidance behaviour towards dried meadow saffron in hay are missing. Reports of farmers are contrary to clinical symptoms described in case reports and associated with meadow saffron in hay. The aim of this study was to determine the rejection behaviour of horses for hay contaminated with meadow saffron (MS) when fed ad libitum. An 18-day feeding trial with six adult geldings to observe the rejection behaviour for hay contaminated with MS. The horses were fed a basal diet containing hay ad libitum and a mineral supplement during the feeding trial. At six different daytimes, hay contaminated with 1% or 2% dried MS was provided to the horses over a duration of 1h. The rejection behaviour was observed personally and by video recordings. If a horse ingested more than two plants of MS during one observation period, the observation was stopped and repeated at another day. When the observation period had to be stopped twice, the horse was excluded from the experiment. Five of six horses ingested MS during the first feeding periods. One horse rejected leaves and capsules at the beginning of the study, but it showed repeated ingestion of MS after the seventh observation period. Lack of knowledge about secondary plant metabolites affecting taste and their variability between fresh and dried plants. The intake of MS in hay by horses could not be ruled out with certainty. Therefore, feeding hay contaminated with MS should be avoided for equids.

Analysis of Egg Variation and Foreign Egg Rejection in Rüppell’s Weaver (Ploceus galbula)

Egg appearance is notable for its variation and as a source of recognition cues in bird species that are subject to egg-mimicking brood parasitism. Here I analyze the egg appearance of an East African weaverbird species that has variable eggs and is a host of brood parasitism by an egg-mimicking cuckoo, in order to (1) compare population variation to variation within a clutch as a measure of the distinctiveness of eggs; (2) assess modularity versus correlation among egg appearance traits as an indication of the complexity of egg signatures; and (3) address whether the eggs are discretely polymorphic or continuously variable in appearance. I also compare three methods of assessing egg coloration: reduction of spectral data to orthogonal components, targeted spectral shape variables, and avian visual modeling. Then I report the results of egg replacement experiments that assess the relationship between egg rejection behavior and the difference in appearance between own and foreign eggs. Rüppell’s weaver (Ploceus galbula) eggs are variable in appearance between individuals and consistent within a clutch, but vary widely in the distinctiveness of particular traits. Most aspects of color and spotting are decoupled from each other, including coloration likely to derive from different pigments. Egg ground color is bimodal, with a broad continuous class of off-white/UV eggs and another broad class of blue-green eggs. Variation in all other traits is unimodal and usually normal in distribution. Females reject foreign eggs on the basis of the difference in brightness of the ground color and spotting of foreign eggs relative to their own, and the difference in degree to which spots are aggregated at the broad end of the egg. This aggregation is among the most distinctive features of their eggs, but the brightness of the ground color and spotting brightness are not; the birds’ use of brightness rather than the more distinctive chromatic variation to recognize eggs might reflect the salience of achromatic contrast in a dim enclosed nest.

High performance graphene-oxide doped cellulose acetate based ion exchange membrane for environmental remediation applications

ABSTRACT This study illustrates the preparation of graphene oxide (GO) impregnated cellulose acetate (CA) ion exchange membrane (IEM). The compositional ratio of GO/CA/polyethylene glycol for preparing cation exchange membranes was optimised for ion exchange capacity (IEC), fixed charged density, water uptake, swelling degree and proton conductivity. Proton conductivity of 0.273 S cm−1 and IEC of 1.08 m mol/g at 30°C was obtained for the membrane with highest GO% (CAG3). The modified CAG3 membrane had better hydrophilicity with a contact angle of 53.4°. Based on the ion exchange property, the membrane was utilised to study the rejection behaviour of both cationic and anionic dyes along with its acid recovery performance in the presence of different salts. It was observed for highest GO-incorporated membrane CAG3 that the acid recovery increased to 61% (1.78 × 102 moles H+ ions/m2h). Low rejection rate for cationic dye (~20%) and high rejection for anionic dye (~92.5%) was obtained. The selective higher rejection of anionic dye along with better acid recovery confirms the formation of a better IEM with enhanced proton conductivity. Furthermore, on analysing for real-life water samples, obtained results showed that the rejection percentage and H+ ion molar flux rate decreased to 1.7% and 17.4%, respectively.

Removal of heavy metals by surface tailored copper ion enhanced ceramic-supported-polymeric composite nanofiltration membrane

Ceramic-supported-polymeric (CSP) composite membranes combine the benefits of robust ceramic support with tunable surface properties of polymeric active layer. The present work reports the fabrication of novel CSP composite nanofiltration membranes wherein surface ionization of the membrane active layers has been carried out by a facile process of chelating copper ions with the crosslinked polyethyleneimine polymer matrix of membrane top layer. Different concentrations of copper chloride solutions were used and their effect on membrane surface properties was investigated using EDX, XPS and AFM analyses. Performance of the membranes in removal of both cationic and anionic heavy metals, namely, Ni(II), Cd(II), Pb(II), Zn(II), As(V) and Cr(VI) from aqueous solution was studied. Excellent removal (> 95%) of all the heavy metals and optimum flux was achieved in case of GPCu0.5 membrane (surface modified with 0.5 wt% copper chloride solution). No significant decrease in flux and rejection rate of the membrane during 10 h high pressure (8 bar) operation suggested longevity of the membrane. The slow release of copper ions indicated the much-expected anti-biofouling nature of the membrane. Appreciable rejection behavior of the copper ion enhanced CSP composite membrane towards multiple heavy metals demonstrates its potential for practical water treatment application.

Altruistic Giving Toward Refugees: Identifying Factors That Increase Citizens' Willingness to Help.

Over the past decade, the world has faced an unprecedented refugee crisis. The large number of incoming refugees represents a challenge for host societies and its citizens triggering reactions from a supportive welcome to brusque rejection and hostile behavior toward refugees. In a pre-registered study, we investigated factors that could promote altruistic behavior in fully incentivized one-shot Dictator Game toward various receiver groups including refugees. We find that host citizens behave more altruistically toward refugees and other receiver groups if they (a) share a local identity with them (i.e., live in the same city), and (b) perceive them to be close (to the self) and warm-hearted. Moreover, citizens that are (c) generally more prosocial and hold a more left-wing political orientation are more willing to give. Unexpectedly, from a theoretical point of view, altruistic giving toward refugees was not influenced in the predicted direction by a shared student identity, competition and perceived income differences (although the latter effect was significant when considering all receiver groups). For shared student identity we even observe a reduction of altruistic behavior, while the opposite effect was predicted. We discuss implications for public policies for successful refugee helping and integration.

In-situ grown inorganic layer coated PVDF/PSF composite hollow fiber membranes with enhanced separation performance

Poly(vinylidene fluoride) (PVDF) membranes are widely employed for water treatment but mainly limited by their hydrophobic properties that increase the separation resistance. To make hydrophilic PVDF membranes, inorganic layer coated PVDF blend hollow fiber membranes are reported here. PVDF/polysulfone (PSF) blend hollow fiber membranes with pore size of ~110 nm were fabricated using PolarClean as a green solvent. Then, a facile and green method was employed to in-situ grow an inorganic layer (including TiO2 and Al2O3 layers) on these high strength membranes. Pluronic L61 was used as a dispersing agent to distribute the precursors in isopropanol, and enhanced adhesive strength between the polymer membrane and inorganic particles as characterized by XPS. The inorganic layers on the PVDF/PSF membrane surface both improved the mechanical strength from 7.7 MPa to 9.2 MPa and decreased the membrane roughness from ~50 nm to ~10 nm. The water permeance of the composite membranes can be finely tuned from 50 to 500 Lm−2h−1bar−1. In addition, the resulting membranes simultaneously enhanced the separation performance and anti-fouling performance characterized by bovine serum albumin (BSA) rejection behavior and flux recovery rate (FRR), respectively. The best BSA rejection and FRR of the PVDF/PSF-inorganic composite membranes reach 95% and 72.2%, respectively. The anti-fouling performance of composite membranes is mainly attributed to the decreased membrane roughness and enhanced hydrophilic properties compared with pristine PVDF/PSF membranes. Furthermore, the in-situ grown inorganic layers on the PVDF/PSF membrane surface effectively prevent foulants from blocking the pore channels as they are easily washed by the hydraulic washing method.