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Background Brucellosis, as a serious zoonotic infectious disease, has been recognized as a re-emerging disease in the developing countries worldwide. In china, the incidence of brucellosis is increasing each year, seriously threatening the health of humans as well as animal populations. Despite a quite number of diagnostic methods currently being used for brucellosis, innovative technologies are still needed for its rapid and accurate diagnosis, especially in area where traditional diagnostic is unavailable. Methodology/Principal findings In this study, a total of 22 B cell linear epitopes were predicted from five Brucella outer membrane proteins (OMPs) using an immunoinformatic approach. These epitopes were then chemically synthesized, and with the method of indirect ELISA (iELISA), each of them displayed a certain degree of capability in identifying human brucellosis positive sera. Subsequently, a fusion protein consisting of the 22 predicted epitopes was prokaryotically expressed and used as diagnostic antigen in a newly established brucellosis testing method, nano-ZnO modified paper-based ELISA (nano-p-ELISA). According to the verifying test using a collection of sera collected from brucellosis and non-brucellosis patients, the sensitivity and specificity of multiepitope based nano-p-ELISA were 92.38% and 98.35% respectively. The positive predictive value was 98.26% and the negative predictive value was 91.67%. The multiepitope based fusion protein also displayed significantly higher specificity than Brucella lipopolysaccharide (LPS) antigen. Conclusions B cell epitopes are important candidates for serologically testing brucellosis. Multiepitope fusion protein based nano-p-ELISA displayed significantly sensitivity and specificity compared to Brucella LPS antigen. The strategy applied in this study will be helpful to develop rapid and accurate diagnostic method for brucellosis in human as well as animal populations., Author summary Brucellosis is one of the most important zoonosis in the world and has caused tremendous economic losses in agriculture and animal husbandry in many countries. Developing rapid, sensitive and specific diagnostic methods is very important for early detection and treatment of brucellosis patients. In this study, a novel diagnostic technique, nano-ZnO modified paper ELISA, was established. The antigen used in this technique was a fusion protein containing multiple B cell epitopes, which were predicted from Brucella major outer membrane proteins such as Bp26, Omp31, Omp16, Omp2b and Omp25. Comparing to traditional LPS antigen, this multiepitope based antigen displayed considerably higher sensitivity and higher specificity in laboratory. With the strategy described in this paper, more efficient epitopes and protein antigen can be identified in the future. Currently, LPS antigen is only prepared from live Brucella, while protein antigen can be produced in large quantities in prokaryotic expression system. In addition to nano-p-ELISA, this protein antigen can also be used for development other methods such as fluorescent polarization assay (FPA) and immunochromatographic assay (ICA) to meet the varied demand for brucellosis testing.

Blood filter paper strips are cost-effective materials used to store body fluid specimens under challenging field conditions, extending the reach of zoonotic pathogen surveillance and research. We describe an optimized procedure for the extraction of parasite DNA from whole blood (WB) stored on Type I Advantec Nobuto strips from both experimentally spiked and field-collected specimens from canine and skunks, respectively. When comparing two commercial kits for extraction, Qiagen’s DNeasy Blood &amp, Tissue Kit performed best for the detection of parasite DNA by PCR from Trypanosoma cruzi-spiked canine WB samples on Nobuto strips. To further optimize recovery of β-actin from field-collected skunk WB archived on Nobuto strips, we modified the extraction procedures for the Qiagen kit with a 90 °C incubation step and extended incubation post-addition of proteinase K, a method subsequently employed to identify a T. cruzi infection in one of the skunks. Using this optimized extraction method can efficaciously increase the accuracy and precision of future molecular epidemiologic investigations targeting neglected tropical diseases in field-collected WB specimens on filter strips.

Drought is a key factor restricting plant survival, growth and development. The physiological parameters of plants are commonly used to determine the water status, in order to irrigate appropriately and save water. In this study, mulberry (Morus alba L.) and paper mulberry (Broussonetia papyrifera (L.) Vent.) seedlings were used as experimental materials, and four soil moisture treatments were set up for both plant species: 70–75% (CK: the control group, referred to as T0), 55–60% (T1: mild drought), 40–45% (T2: moderate drought), and 25–30% (T3: severe drought). The growth parameter of the plants was measured every two days from the onset of the treatment, the photosynthetic and electrophysiological parameters of the plants were measured every other week for a total of five times. The physiological responses and electrophysiological traits of leaves under different treatment levels were analyzed. The results showed that the photosynthetic and electrophysiological parameters could characterize the response of mulberry growth and development to soil water, and the growth and electrophysiological parameters could characterize the response of paper mulberry growth and development to soil water. Mild drought had no significant effects on the growth and development of mulberry and paper mulberry.

This study evaluates the efficacy of using textile waste blended with paper waste to form biodegradable seedling pots. A bio-composite blend of cotton (20% cotton, 40% newspaper, and 40% corrugated cardboard) and polycotton (20% polycotton, 40% newspaper, and 40% corrugated cardboard) with an optimum strength was formed into seedling pots. The appreciated seedling pots (untreated blends of cotton and polycotton) were compared with the commercial pots (cardboard seed starter pot and Jiffy pot) in terms of mechanical properties (tensile strength and compressive strength), biodegradability (soil burial test and anaerobic digestion), and seed germination. The untreated blends of cotton and polycotton pots demonstrated a comparable optimum strength, while the Jiffy pot and cardboard seed starter pot obtained the least tensile and compressive strengths, respectively. The anaerobic biodegradability assay suggests that the cotton blend pot, polycotton blend pot, and cardboard seed starter pot can degrade anaerobically because of high biogas and methane generation potential. A 100% seed germination was observed from the four seedling pots tested. Thus, the results demonstrate the efficacy of utilizing textile waste and paper waste to develop seedling pots with desirable strength and biodegradability compared to the commercial pots.

A newly modified paper-based enzyme-linked immunosorbent assay (P-ELISA) was established by immobilizing more proteins on the paper surface through an atom transfer radical polymerization (ATRP) reaction. In addition, introducing graphene oxide (GO) sheets, Au nanoparticles (AuNps) and two primary antibodies (Ab1s) led to signal amplification and cost reduction. Electronic supplementary material The online version of this article (10.1186/s13065-019-0622-7) contains supplementary material, which is available to authorized users.

This study investigates the efficacy of using discarded textile (cotton and polycotton) and paper waste (newspaper and corrugated cardboard) as substrates to form sheets with optimum tensile strength. The effect of alkali treatment (sodium hydroxide (NaOH) and sodium bicarbonate (NaHCO3)), compressive loads (200 N and 500 N), and the use of binding agents (blackstrap molasses, sodium alginate, and cornstarch) were studied to optimize the tensile strength of homogeneous sheets. The alkali treatment using 5% NaOH for 5 h of soaking demonstrated the highest increase in tensile strength of 21% and 19% for cotton and newspaper, respectively. Increasing compressive load from 200 N to 500 N showed the highest increase in tensile strength of 37% and 42% for cotton and newspaper, respectively. Remarkably, among the binders, cornstarch at 20% concentration obtained an increase in tensile strength of 395%, 320%, 310%, and 185% for cotton, polycotton, corrugated cardboard, and newspaper sheets, respectively. The optimum results obtained from this study will be utilized to develop biodegradable seedling pots using discarded textile and paper waste.

The present study investigated the effects of dietary paper mulberry (Broussonetia Papyrifera, BP) on growth performance, muscle quality and muscle growth-related mRNA expressions of grass carp. Fish (initial weight: 50.0 ± 0.5 g) were fed diets supplemented with 0% (control diet), 5%, 10%, 15% and 20% BP for 8 weeks. The results showed that increasing levels of paper mulberry linearly and quadratically decreased the special gain rate (SGR) and increased the feed conversion rate (FCR) of grass carp (p &lt, 0.05). Significantly positive quadratic trends were found between paper mulberry levels and muscle crude fat or crude protein of grass carp (p &lt, 0.05). In comparison to the control diet, the 10%BP and 15%BP groups had significantly decreased muscle crude fat and increased crude protein (p &lt, 0.05). The levels of paper mulberry resulted in a linear and quadratic increase in water loss of grass carp muscle (p &lt, 0.05), and all groups with paper mulberry supplementation were significantly higher than the control group (p &lt, 0.05). Significant positive linear and quadratic trends were found between the paper mulberry levels and muscle fiber diameter or density of grass carp (p &lt, 0.05). In comparison to the control diet, the significant differences were found in the 15%BP and 20%BP groups (p &lt, 0.05). The muscle adhesiveness and hardness linearly and quadratically increased with the increasing levels of paper mulberry (p &lt, 0.05), and both of which increased significantly when the level of paper mulberry reached 10% (p &lt, 0.05). In addition, the increase in paper mulberry linearly and quadratically improved the expressions of myoblast determination protein (MyoD), myogenin (MyoG), paired box protein 7 (Pax7) and myostatin 1 (MSTN1) (p &lt, 0.05). When the supplementation of paper mulberry reached 15%, the expressions of all these mRNAs were significantly higher than those of the control group (p &lt, 0.05). In summary, adding 5% paper mulberry did not affect the growth of grass carp. However, the supplementation of 10% paper mulberry could improve muscle quality through improving muscle hardness, reducing fat accumulation and muscle fiber diameter, at the cost of reducing growth performance.

Lactic acid bacteria occupy an important position in silage microorganisms, and the effects of exogenous lactic acid bacteria on silage quality have been widely studied. Microbial metabolism has been proved as an indicator of substrate utilization by microorganisms. Paper mulberry is rich in free carbohydrate, amino acids, and other components, with the potential to be decomposed and utilized. In this study, changes in the microbial metabolism characteristics of paper mulberry silage with Lactiplantibacillus plantarum (LP) and Lentilactobacillus buchneri (LB) were studied along with a control (CK) using BIOLOG ECO microplates. The results showed that average well-color development (AWCD), Shannon diversity, Shannon evenness, and Simpson diversity exhibited significant temporal trends. LB and LP responded differently in the early ensiling phase, and the AWCD of LB was higher than LP at 7 days. Principal component analysis revealed that CK, LB, and LP samples initially clustered at 3 days and then moved into another similar cluster after 15 days. Overall, the microplates methodology applied in this study offers important advantages, not least in terms of accuracy.

Precooling and sulfur dioxide fumigation were proved as effective methods for the preservation of longan (Dimocarpus longan Lour.) fruits. However, inadequate precooling and sulfur dioxide fumigation resulted in unexpected losses and short shelf life. A L9(34) orthogonal test was conducted to screen out ideal dosage of sodium metabisulfite (factor A), precooling method (factor B), and precooling duration (factor C) to improve the storability of longan fruit stored for 48 hr at room temperature (RT) (25℃). The overall qualities of all of the treated longan fruits after a 48‐hr storage (OQST) and during the 5‐day shelf at 25℃ (OQSF) were better than those of the control fruits. The treated fruits showed brighter fresh color (higher L*, b*, C*, and h° values but lower a* value), higher flavonoid, and chlorophyll contents. Moreover, the SO2 residue was concentrated in pericarp but little in aril for any of the 12 treatments. The multivariate variance analysis showed that factor A was dominant to determine both of the OQST and OQSF, while factor B affected the OQST, and factor C affected the OQSF. In total, “0.22% sodium metabisulfite + 4 hr precooling + uncovered precooling” was considered to be an ideal treatment. These results would contribute to improving longan postharvest preservation technology., The overall qualities of all of the treated longan fruits after a 48‐hr storage (OQST) and during the 5‐d shelf at 25℃ (OQSF) were better than those of the control fruits. The treated fruits showed brighter fresh color (higher L*, b*, C*, and h° values but lower a* value), higher flavonoid, and chlorophyll contents. Factor A (dosage of sodium metabisulfite) was the dominant factor, and “0.22% sodium metabisulfite + 4 hr precooling + uncovered precooling” was considered to be an ideal treatment.

The recycled paper industry produces tons of waste whose disposal is a cost for industry and the environment. This research examines the suitability of de-inked paper sludge (DPS), after pelletization, as a sustainable alternative component to a peat-based growing media, creating ideal root conditions for tree development (e.g. high water storage, low compaction). DPS, tested on Lepidium sativum L. germination, did not show toxicity effects. Three species, Quercus ilex L., Lagerstroemia indica L. and Prunus serrulata “Kanzan”, were planted in 40 cm O pots filled with a control (peat, pumice and zeolite) and the experimental substrate (compost, DPS pellets, pumice and zeolite). After two years in the nursery, the trees were planted in situ. The physical and chemical properties of substrates were analyzed. Plant morphological and physiological parameters were monitored: trunk diameter, leaf dry matter, leaf nitrogen, chlorophyll, and photosynthetic efficiency. The new substrate showed higher Corg (+135%), total N (+73%) and easily available water (+19%), compared to the control substrate used in the nursery. In this new substrate, the trees showed similar radial growth values to the control in the nursery and after transplanting in situ improved their photosynthetic performance in terms of quantum yield of photosystem II (+36%, and +29% in P. serrulata and L. indica, respectively) and electron transport rate (+39%, +25%, and +32% in P. serrulata, Q. ilex and L. indica, respectively). Pelletization represents an attractive amendment for growing media, which enhances the plant’s physiological health status. This study proposes alternative recovery methods for paper industry waste with low environmental impact. As the process is developed locally, it should also contribute to reducing energy-related CO2 emissions from transport. Pelletization represents an attractive novelty in the use of DPS as amendment for growing media, which enhances the plant’s physiological health status. This study proposes alternative recovery methods for paper industry waste with low environmental impact. As the process is developed locally, it should also contribute to reducing energy-related CO2 emissions from transport.

Detection methods for monitoring infectious pathogens has never been more important given the need to contain the spread of the COVID-19 pandemic. Herein we propose a highly sensitive magnetic-focus-enhanced lateral flow assay (mLFA) for the detection of SARS-CoV-2. The proposed mLFA is simple and requires only lateral flow strips and a reusable magnet to detect very low concentrations of the virus particles. The magnetic focus enhancement is achieved by focusing the SARS-CoV-2 conjugated magnetic probes in the sample placed in the lateral flow (LF) strips for improved capture efficiency, while horseradish peroxidase (HRP) was used to catalyze the colorimetric reaction for the amplification of the colorimetric signal. With the magnetic focus enhancement and HRP-based amplification, the mLFA could yield a highly sensitive technology for the recognition of SARS-CoV-2. The developed methods could detect as low as 400 PFU/mL of SARS-CoV-2 in PBS buffer based on the visible blue dots on the LF strips. The mLFA could recognize 1200 PFU/mL of SARS-CoV-2 in saliva samples. With clinical nasal swab samples, the proposed mLFA could achieve 66.7% sensitivity and 100% specificity.

This study explores consumers' visual sustainability impressions of paper-based packaging that has incorporated obvious waste content. Two research questions were addressed concerning (i) the environmental sustainability perception of noticeable waste content in packaging and (ii) the impact of the presentation format (i.e., online versus in-person surveys) when studying these perceptions. Best-worst scaling experiments were conducted, which made respondents choose the 'most' and 'least' environmentally friendly package. Packages were designed using paperboard substrates blending either brown linerboard or white hardwood pulp with different recovered waste materials. The results showed that consumers perceive obvious waste-containing packaging as more environmentally friendly than classical packaging (with no visual waste). Samples with a brown base and agricultural waste were perceived as more sustainable compared to white packaging and the use of paper waste. In addition, the presentation format changed respondents' perception, and should therefore be carefully considered when designing surveys.

Water hyacinth (WH) is considered as the worst aquatic weed in the world because of its rapid growth and fast spread into new areas of fresh water bodies. We investigated the potentiality of using WH as a raw material for production of handmade paper and compost in Bangladesh. Potash pulping was done using potassium hydroxide (KOH) at different alkali concentrations (8–12%) with a liquor to solid ratio of 7:1 at 145 °C for 2 h. The pulp was bleached using hydrogen peroxide (H2O2), and pulp properties (brightness, tear index and tensile index) of bleached and unbleached pulps were analyzed following the respective TAPPI standards. The produced black liquor was mixed with WH along with kitchen bio-wastes to produce compost. The properties of the compost were tested following the published protocols, i.e., wet digestion, Kjeldahl, vanadomolybdophosphoric acid, and Flame Spectrophotometry methods. Brightness, tensile index and tear index of bleached hand sheets were found to be 37.2%, 49.2 N m/g and 6.79 m.Nm2/g, respectively suggesting significant contribution of bleaching on WH paper quality. Addition of black liquor significantly increased the nitrogen and potassium content of bio-waste compost. Thus, WH can be used as a raw material for making handmade paper while the process by-product can be supplemented to improve the nutritional quality of compost. Such cottage-industry fabrication of WH green products could be developed to control the infestation of WH in water bodies, and this technology may provide for new possible sustainable livelihood option.

The social paper wasp Agelaia pallipes is known to eat carrion and scavenge on vertebrates. There are few records of wasps predating vertebrates, including an attack on an adult hummingbird and the predation of bird nestlings. During a project monitoring reproductive behaviour of a neotropical songbird, the Lined Seedeater Sporophila lineola in south-eastern Brazil, we recorded the predation of a four-day-old nestling by a social paper wasp. In the video, the adult female bird attempted to visit the nest prior to the predation. The male could be seen with its crest feathers erect after a wasp left the nest, when the nestling was presumably already dead. When we arrived at the nest to remove the camera, we found the nestling dead, and did not observe the parents in the vicinity. We also registered two other dead nestlings in a different nest with similar wounds. However, the conclusive cause of death of those nestlings is unknown. Nest predation is a major selective pressure in birds, and insects are rarely assumed to play a notable role in this process. Further research is needed to better understand the nature of the relationship between wasps and birds.

Indigenous plants are widely abundant in Mauritius and if made proper use of, these renewable plants can contribute largely to the local economic sector. This paper assesses the suitability of producing eco-friendly and biodegradable papers using low-cost raw materials by means of fibre from Pandanus utilis’ leaves commonly known as ‘Vacoas’. The leaves were used along with Arundo donax or wastepaper to manufacture composite paper samples in the ratios of 20:80, 40:60, 60:40, 80:20 and 100:0. Chemical pulping was done through Kraft process for a period of 1.5 h at a concentration of 14 wt% NaOH and 4 wt% Na2S at 90 ± 2.5 °C. The mean thickness of the papers was determined to be 0.261 ± 0.027 mm. It was found that the 100% Vacoas fibres had the highest absorbency rate of 1.8 ± 0.5 s followed by the composite A. donax and Vacoas fibre (1.8 ± 0.3 s). The most abrasion resistant paper which also demonstrated the highest burst index of 0.63 kPa m2 g− 1 and tensile index 11.8 N m g− 1 was observed to be that of 100:0 Vacoas fibre paper requiring 35 turns to get abraded followed by the P. utilis and A. donax mix where the 80:20 fibre ratio revealed a high bursting index of 0.45 kPa m2 g− 1 requiring 25 turns to get abraded while 40% P. utilis and 60% A. donax had a high tensile strength of 11.9 N m g− 1. Vacoas to wastepaper mix ratios of 20:80 and 40:60 were found to have the highest mean recovery angles of 61.3 and 59.6°, respectively.

Developmental studies of brain volumes can reveal which portions of neural circuits are sensitive to environmental inputs. In social insects, differences in relative investment across brain regions emerge as behavioural repertoires change during ontogeny or as a result of experience. Here, we test the effects of maturation and social experience on morphological brain development inPolistes fuscatuspaper wasps,focusing on brain regions involved in visual and olfactory processing. We find that mature wasps regardless of social experience have relatively larger brains than newly emerged wasps and this difference is driven by changes to mushroom body calyx and visual regions but not olfactory processing neuropils. Notably, social wasps invest more in the anterior optic tubercle (AOT), a visual glomerulus involved in colour and object processing in other taxa, relative to other visual integration centres the mushroom body calyces compared with aged socially naive wasps. Differences in developmental plasticity between visual and olfactory neuropil volumes are discussed in light of behavioural maturation in paper wasps, especially as it relates to social recognition. Previous research has shown thatP. fuscatusneed social experience to develop specialized visual processing of faces, which is used to individually recognize conspecifics. The present study suggests that the AOT is a candidate brain region that could mediate facial processing in this species.

Effluents from a pulp and paper mill in India were analyzed for various physicochemical parameters and heavy metals. Multivariate statistical analysis was used to interpret the data obtained and predict the toxicity of each component to Cyprinus carpio L. fingerlings. The results showed that most of these parameters exceeded recommended levels set by various agencies, and the effluent was not suitable for discharge into agricultural fields or water bodies without further treatment. The results of static renewal toxicity tests revealed median lethal concentrations at 24, 48, 72, and 96 h to be 42, 25, 18.6 and 14.5%, respectively, and the fingerlings exhibited severe behavioral anomalies. The sublethal dose of 2.9% (v/v) caused alterations in the gill and liver at durations of 7, 14, 21, and 28 d. Anomalies such as mucous secretion, leucocyte infiltration, curling of the secondary lamellae tip, clubbing, and the fusion of the secondary lamellae, aneurism, etc. were prominent. The liver showed inflammatory infiltration, cytoplasmic inclusion bodies, vacuolar degeneration, fatty degeneration, pyknosis, karyolysis, distorted pancreatic area, and piecemeal necrosis, among other pathological symptoms. The study concluded that the effluent, even in greatly diluted form, was highly toxic and the severity of responses depended on the length of exposure.

Graphical abstract, Highlights • Detection of cytokine storm biomarkers with mobile biosensors. • Immunosensors are made solely of cellulose modified with antibody-decorated nanoparticles. • Turnaround time under 10 min. • Detection of biomarkers in respiratory samples allows monitoring local inflammation. • Compatible with decentralized health care schemes., Decentralizing COVID-19 care reduces contagions and affords a better use of hospital resources. We introduce biosensors aimed at detecting severe cases of COVID-19 in decentralized healthcare settings. They consist of a paper immunosensor interfaced with a smartphone. The immunosensors have been designed to generate intense colorimetric signals when the sample contains ultralow concentrations of IL-6, which has been proposed as a prognosis biomarker of COVID-19. This is achieved by combining a paper-based signal amplification mechanism with polymer-filled reservoirs for dispensing antibody-decorated nanoparticles and a bespoken app for color quantification. With this design we achieved a low limit of detection (LOD) of 10−3 pg mL-1 and semi-quantitative measurements in a wide dynamic range between 10−3 and 102 pg mL-1 in PBS. The assay time is under 10 min. The low LOD allowed us to dilute blood samples and detect IL-6 with an LOD of 1.3 pg mL-1 and a dynamic range up to 102 pg mL-1. Following this protocol, we were able to stratify COVID-19 patients according to different blood levels of IL-6. We also report on the detection of IL-6 in respiratory samples (bronchial aspirate, BAS) from COVID-19 patients. The test could be easily adapted to detect other cytokines such as TNF-α and IL-8 by changing the antibodies decorating the nanoparticles accordingly. The ability of detecting cytokines in blood and respiratory samples paves the way for monitoring local inflammation in the lungs as well as systemic inflammation levels in the body.

An origami three-dimensional design of a paper-based potentiometric sensor is described. In its simplest form, this electrochemical paper-based analytical device (ePAD) is made from three small parts of the paper. Paper layers are folded on each other for the integration of a solid contact ion selective electrode (here a carbon-paste composite electrode) and a solid-state pseudo-reference electrode (here writing pencil 6B on the paper), which are in contact with a hydrophilic channel fabricated on the middle part (third part) of the paper. In this case, the pseudo-reference and working electrodes are connected to the two sides of the hydrophilic channel and hence the distance between them is as low as the width of paper. The unmodified carbon paste electrode (UCPE) and modification with the crown ether benzo15-crown-5 (B15C5) represented a very high sensitivity to Cu (II) and Cd2+ ions, respectively. The sensor responded to H2O2 using MnO2-doped carbon paste electrode (CPE). Furthermore, a biosensor was achieved by the addition of glucose oxidase to the MnO2-doped CPE and hence made it selective to glucose with ultra-sensitivity. In addition to very high sensitivity, our device benefits from consuming a very low volume of sample (10.0 µL) and automatic sampling without need for sampling devices.

This paper proposes a combined strategy of using paper-based competitive immunochromatography and a near field communication (NFC) tag for wireless cotinine determination. The glucose oxidase labeled cotinine antibody specifically binds free cotinine in a sample, whereas the unoccupied antibody attached to BSA-cotinine at the test line on a lateral flow strip. The glucose oxidase on the strip and an assistant pad in the presence of glucose generated H2O2 and imposed the Ag oxidation on the modified electrode. This enabled monitoring of immunoreaction by either electrochemical measurement or wireless detection. Wireless sensing was realized for cotinine in the range of 100–1000 ng/mL (R2 = 0.96) in PBS medium. Undiluted urine samples from non-smokers exhibited an Ag-oxidation rate three times higher than the smoker’s urine samples. For 1:8 diluted urine samples (smokers), the proposed paper-based competitive immunochromatography coupled with an enzyme-modified electrode differentiated positive and negative samples and exhibited cotinine discrimination at levels higher than 12 ng/mL. This novel sensing platform can potentially be combined with a smartphone as a reader unit.

When whitewater circuits in the paper industry are closed, organic compounds accumulate and cause adverse production problems, such as the formation of slime and pitch. Since wood-free whitewater is usually a mixture of additives for paper production and an efficient cost-effective purification technology for their removal is lacking, the aim of our study was to find an effective bio-based strategy for whitewater treatment using a selection of indigenous bacterial isolates. We first obtained a large collection of bacterial isolates and then tested them individually for their ability to degrade the organic additives used in papermaking, i.e. carbohydrates, resin acids, alkyl ketene dimers, polyvinyl alcohol, latex, and azo and fluorescent dyes. Out of the 355 bacterial isolates, we selected a combination of four strains (Xanthomonadales bacterium sp. CST37-CF, Sphingomonas sp. BLA14-CF, Cellulosimicrobium sp. AKD4-BF and Aeromonas sp. RES19-BTP), which cover the entire spectrum of the tested organic additives. A proof-of-concept study in pilot scale was then performed by immobilizing the cells of our artificial bacterial consortium in a 33-liter tubular flow-through reactor with a retention time of Graphical abstractHighlightsA strategy for selecting a consortium of indigenous bacteria with a high potential for bioaugmentation of wood-free whitewater is presented.Study of bacterial degradation of eight chemically diverse substances used in paper production is presented. Methods for the selection of bacteria suitable for industrial application were developed.The constructed artificial bacterial consortium consisted of strains belonging to genera Xanthomonadales bacterium, Sphingomonas, Aeromonas and Cellulosimicrobium.The proof of concept of the industrial application, consisting of a 33-L-column filled with the immobilized artificial consortium, was an 88% decrease in COD of the whitewater effluent.

Fibrinogen concentration is a major determinant of both clotting and bleeding risk. Clotting and bleeding disorders cause extensive morbidity and mortality, particularly in resource-poor and emergency settings. This is exacerbated by a lack of timely intervention informed by measurement of fibrinogen levels under conditions such as thrombosis or postpartum haemorrhage. There is an absence of simple, rapid, low-cost, and sustainable diagnostic devices for fibrinogen measurement that can be deployed in such environments. Paper-based analytical devices are of significant interest due to their potential for low-cost production, ease of use, and environmental sustainability. In this work, a device for measuring blood plasma fibrinogen using chromatography paper was developed. Wax printing was used to create hydrophobic structures to define the test channel and sample application zone. Test strips were modified with bovine thrombin. Plasma samples (22 μL) were applied, and the flow rate was monitored over 5 min. As the sample traversed the strip, clotting was induced by the conversion of soluble fibrinogen to insoluble fibrin. The flow rate and distance travelled by the sample were dependent on fibrinogen concentration. The device was able to measure fibrinogen concentration in the range of 0.5–7.0 ± 0.3 mg/mL (p < 0.05, n = 24) and had excellent correlation with laboratory coagulometry in artificial samples (r2 = 0.9582, n = 60). Devices were also stable at 4–6 °C for up to 3 weeks.

Refereed/Peer-reviewed Nectar analysis has been used to understand pollination systems, but nectar storage methods have rarely been considered as potential sources of inaccuracy in the recovery of data. Prompt nectar sugar analysis is not always possible and storage methods can affect results. We aimed to develop an effective method to store nectar on filter paper. Nectars from two subspecies of Eremophila maculata (Scrophulariaceae) and Strelitzia reginae (Strelitziaceae) were spotted on filter papers. Nectars were redissolved and assayed by high-performance liquid chromatography to determine the masses of sugars recovered from the papers from Day 0 to Day 30. We evaluated the effects of the method of elution, paper type and size, and storage treatments on sugar recovery. Liquid nectars were also stored in the refrigerator. Sugars were best eluted from filter papers in 15 mL of water and agitated for 1 min. Nectar sugars stored on small papers tended to be recovered more successfully than those stored on larger papers (significantly for glucose). Paper performed better than nylon for glucose. Desiccant had a marginal positive effect on nectar sugar recovery, and filter paper performed better than did refrigeration of liquid nectar for storage. If highly accurate measurements are needed, nectars should be eluted with large volumes of water from small filter papers stored with desiccant within a few days of collection.