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Microfluidic paper-based analytical devices (microPADs) are emerging as simple-to-use, low-cost point-of-care testing platforms. Such devices are mostly fabricated at present by creating hydrophobic barriers using wax or photoresist patterning on porous paper sheets. Even though devices fabricated using these methods are used and tested with a wide variety of analytes, still they pose many serious practical limitations for low-cost automated mass fabrication for their widespread applicability. We present an affordable and simple two-step process - cut and heat (CH-microPADs) - for the selective fabrication of hydrophilic channels and reservoirs on a wide variety of porous media such as tissue/printing/filter paper and cloth types, such as cotton and polyester, by a lamination process. The technique presents many advantages as compared to existing commonly used methods. The devices possess excellent mechanical strength against bending, folding and twisting, making them virtually unbreakable. They are structurally flexible and show good chemical resistance to various solvents, acids and bases, presenting widespread applicability in areas such as clinical diagnostics, biological sensing applications, food processing, and the chemical industry. Fabricated paper media 96 well-plate CH-microPAD configurations were tested for cell culture applications using mice embryonic fibroblasts and detection of proteins and enzymes using ELISA. With a simple two-step process and minimal human intervention, the technique presents a promising step towards mass fabrication of inexpensive disposable diagnostic devices for both resource-limited and developed regions.

Aβ42 is one of the most extensively studied blood and Cerebrospinal fluid (CSF) biomarkers for the diagnosis of symptomatic and prodromal Alzheimer’s disease (AD). Because of the heterogeneity and transient nature of Aβ42 oligomers (Aβ42Os), the development of technologies for dynamically detecting changes in the blood or CSF levels of Aβ42 monomers (Aβ42Ms) and Aβ42Os is essential for the accurate diagnosis of AD. The currently commonly used Aβ42 ELISA test kits usually mis-detected the elevated Aβ42Os, leading to incomplete analysis and underestimation of soluble Aβ42, resulting in a comprised performance in AD diagnosis. Herein, we developed a dual-target lateral flow immunoassay (dLFI) using anti-Aβ42 monoclonal antibodies 1F12 and 2C6 for the rapid and point-of-care detection of Aβ42Ms and Aβ42Os in blood samples within 30 min for AD diagnosis. By naked eye observation, the visual detection limit of Aβ42Ms or/and Aβ42Os in dLFI was 154 pg/mL. The test results for dLFI were similar to those observed in the enzyme-linked immunosorbent assay (ELISA). Therefore, this paper-based dLFI provides a practical and rapid method for the on-site detection of two biomarkers in blood or CSF samples without the need for additional expertise or equipment. Graphical Abstract

Rabbit hemorrhagic disease virus 2 (RHDV2), a virulent and contagious viral pathogen that affects wild and domestic lagomorph populations, was identified in Wyoming, USA in December 2020. A surveillance program was developed involving full-carcass submission and liver analysis, although carcass quality as a result of predation and decomposition impeded analysis. To increase the number of submissions and provide flexibility to field staff, we evaluated 2 sample types: 77 dried blood on filter paper samples, 66 ear punch samples. At initial sampling, test specificity and sensitivity of the RT-rtPCR utilizing dried blood on filter paper and ear punch samples were both 100% compared to liver. Filter paper results were consistent over time; sensitivity stayed >96% through weeks 2, 4, and 6, with a maximum mean difference of 6.0 Ct from baseline liver Ct values (95% CI: 5.0–7.3) at 6 wk. Test sensitivity of the ear punch sample at 1, 3, 5, and 7 wk post-sampling remained at 100%, with a maximum mean difference of 5.6 Ct from baseline liver Ct values (95% CI: 4.3–6.9) at 5 wk. Filter paper and ear punch samples were suitable alternatives to liver for RHDV2 surveillance in wild lagomorph populations. Alternative sampling options provide more flexibility to surveillance programs, increase testable submissions, and decrease exposure of field personnel to zoonotic disease agents.

Many studies have been conducted on measuring avian influenza viruses and their hemagglutinin (HA) antigens via electrochemical principles; most of these studies have used gold electrodes on ceramic, glass, or silicon substrates, and/or labeling for signal enhancement. Herein, we present a paper-based immunosensor for label-free measurement of multiple avian influenza virus (H5N1, H7N9, and H9N2) antigens using flexible screen-printed carbon nanotube-polydimethylsiloxane electrodes. These flexible electrodes on a paper substrate can complement the physical weakness of the paper-based sensors when wetted, without affecting flexibility. The relative standard deviation of the peak currents was 1.88% when the electrodes were repeatedly bent and unfolded twenty times with deionized water provided each cycle, showing the stability of the electrodes. For the detection of HA antigens, approximately 10-μl samples (concentration: 100 pg/ml–100 ng/ml) were needed to form the antigen–antibody complexes during 20–30 min incubation, and the immune responses were measured via differential pulse voltammetry. The limits of detections were 55.7 pg/ml (0.95 pM) for H5N1 HA, 99.6 pg/ml (1.69 pM) for H7N9 HA, and 54.0 pg/ml (0.72 pM) for H9N2 HA antigens in phosphate buffered saline, and the sensors showed good selectivity and reproducibility. Such paper-based sensors are economical, flexible, robust, and easy-to-manufacture, with the ability to detect several avian influenza viruses.

Allergy to Polistes dominula (European paper wasp) venom is of particular relevance in Southern Europe, potentially becoming a threat in other regions in the near future, and can be effectively cured by venom immunotherapy (VIT). As allergen content in extracts may vary and have an impact on diagnostic and therapeutic approaches, the aim was to compare five therapeutic preparations for VIT of P. dominula venom allergy available in Spain. Products from five different suppliers were analyzed by SDS-PAGE and LC-MS/MS and compared with a reference venom sample. Three products with P. dominula venom and one product with a venom mixture of American Polistes species showed a comparable band pattern in SDS-PAGE as the reference sample and the bands of the major allergens phospholipase A1 and antigen 5 were assignable. The other product, which consists of a mixture of American Polistes species, exhibited the typical band pattern in one, but not in another sample from a second batch. All annotated P. dominula allergens were detected at comparable levels in LC-MS/MS analysis of products containing P. dominula venom. Due to a lack of genomic information on the American Polistes species, the remaining products were not analyzed by this method. The major Polistes allergens were present in comparable amounts in the majority, but not in all investigated samples of venom preparations for VIT of P. dominula venom allergy.

Paper spray ionization (PSI) is an extractive ambient ionization technique for mass spectrometry (MS), whereby a triangular paper tip serves as the sampling base and the electrospray tip. During PSI, analytes are extracted and transported to the edge of the paper tip by the applied spraying solvent. Analytes can be purified from a sample matrix and separated from each other by this transportation process. In this study, we investigated and utilized the analyte transportation process of PSI for the in situ separation and analysis of lipid mixtures. We found that differential transport of phosphatidylcholine (PC) and triacylglycerol (TAG), the two most abundant lipid classes in animals, occurred during PSI. We also found that the order in which these lipids moved strongly depended on how the spraying solvent was applied to the paper base. The more polar PC moved faster than the less polar TAG during PSI, when a polar solvent was slowly fed into a paper tip, whereas TAG was transported faster than PC when excess solvent was applied to the tip at once. In addition, we achieved a complete separation and detection of PC and TAG by slowly supplying a nonpolar solvent to a PSI tip.

Rabies is a deadly viral disease present mainly in low-income countries of Africa and Asia. Dogs are the main reservoir and the source of human deaths. Mass vaccination campaigns of dogs are pivotal to achieve rabies elimination. The monitoring of the immune response of the dog population is necessary to evaluate the effectiveness of these campaigns, taking into account field conditions. This study explores the feasibility and the performance of a new tool using filter papers (FPs) to collect blood samples associated with an Enzyme-Linked ImmunoSorbent Assay (ELISA) titration of rabies antibodies in dogs. A total of 216 eluates from FP samples were collected from 111 dogs kept in experimental facilities in France and 29 dogs from the field in Tunisia. Sera were also analyzed using both the Fluorescence Antibody Virus Neutralization test (FAVNt) and ELISA. A high specificity (98.0%) was obtained by testing FP blood eluates from 51 unvaccinated dogs, with the results compared with those of FAVNt and ELISA on serum samples. The coefficients of concordance between FP eluates and tested sera were 88.9% for FAVNt and 88.0% for ELISA. Blood filter papers coupled with the titration of rabies antibodies by ELISA provide a reliable, simple, and effective solution to overcome the issues of the logistics and transport of samples, especially in low-income countries.

This study reports the simultaneous colorimetric detection of urea, H2O2, and pH in milk samples using microfluidic paper-based analytical devices (μPADs) fabricated through a craft cutter printer. Paper-based devices were designed to contain three detection zones interconnected to a sampling zone by microfluidic channels. Colorimetric analysis was performed using images digitalized through an office scanner. The volumes of chromogenic and sample solutions were optimized, and the best colorimetric performance was achieved by adding 0.5 and 10 μL into detection and sampling zones, respectively. Simultaneous assays were then carried out, and the recorded responses revealed a linear behavior in the concentration ranges from 0–30.0 mmol L−1, 0–10.0 mmol L−1 and 6.0–9.0 for urea, H2O2 and pH, respectively. The limit of detection values obtained for urea and H2O2 were 2.4 mmol L−1 and 0.1 mmol L−1, respectively. For pH measurements, colorimetric assay allowed the monitoring of solution pH with a resolution of 0.25 units. The use of μPADs to detect target adulterants exhibited suitable reproducibility (RSD ≤ 6.0%), accuracy (91–102%) and no cross-reaction occurrence. When compared to reference techniques, colorimetric assays did not reveal a significant difference at a confidence level of 95%. As a proof-of-concept, the feasibility of the proposed approach was successfully demonstrated through the analysis of potential adulterants in sixteen milk samples, which were tested without any pretreatment requirement. Based on the achievements, μPADs in conjunction with colorimetric measurements emerge as a powerful tool for rapid screening of potential adulterants in milk.

Detection and characterization of DNA damage plays a critical role in genotoxicity testing, drug screening, and environmental health. We developed a fully integrated origami paper-based analytical device (oPAD) for measuring DNA damage. This simple device allows on-paper cell lysis, DNA extraction, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) reaction and signal readout with simple operation steps, enabling rapid (within 30 min) and high throughput assessment of multiple DNA damages induced by exogenous chemical agents.

Aristotle is often named as the first zoologist or biologist because of his writings on animals. Although Aristotle’s major intention in these books was to illustrate his ideas of how knowledge and understanding might advance, at least one modern biologist (C. Darwin) has recognized Aristotle's depth and breadth as being of surviving merit. Of greater surprise is the ongoing attention that his works continue to receive, including publications in contemporary scientific journals. This review identifies 38 peer-reviewed papers on various topics from Aristotle’s biological writings that have been published during the last 50 years. These papers are described according to content (genetics, population biology, anatomy, brain, movement), specific creatures (fish, scorpions, elephants, insects, birds), publication outlet, distribution over the fifty year period surveyed, and visible trends in the topics studied. It is concluded that, in the highly-competitive field of peer-reviewed scientific publication and citation, Aristotle's biology continues to excite the interest of scientists and remains salient to modern science itself.

(1) Background: The medical practice of acupuncture involves the insertion of a specialized stainless needle into a specific body point, often called an acupoint, to initiate a perceived phenomenon of de-qi sensation. Therefore, the term “de-qi” describes bodily sensations experienced by the recipient during acupuncture, which may include feelings of soreness, heaviness, fullness, numbness, and migration. However, while acupuncture treatments reportedly result in acupoint activation and an increased release of neurotransmitters or cytokines, detecting these substances released into the acupoint microenvironment is often missed or delayed in clinical and basic practice. (2) Methods: To address this situation, we employed a paper-based enzyme-linked immunosorbent assay method to examine acupoint environmental changes using minute volumes of easily accessible acupoint fluids. (3) Results: Our results indicated that while levels of adenosine triphosphate (ATP), interleukin-1β, interleukin-6, glutamate, substance P, and histamine were all increased in the experimental group following electroacupuncture (EA) treatment, contrary results were observed in the sham EA and transient receptor potential vanilloid 1 (Trpv1−/−) groups. Subsequently, TRPV1 and its associated molecules were augmented in mouse dorsal root ganglion, spinal cord, thalamus, and the somatosensory cortex, then examined by Western blotting and immunofluorescence techniques. Investigations revealed that these elevations were still unobserved in the sham EA or EA in the Trpv1−/− groups. Furthermore, results showed that while administering ATP could mimic EA function, it could be reversed by the ATP P2 receptor antagonist, suramin. (4) Conclusions: Our data provide novel information, indicating that changes in neurotransmitter and cytokine levels can offer insight into acupuncture mechanisms and clinical targeting.

With the appearance of plants and animals, new challenges emerged. These multicellular eukaryotes had to solve for example the difficulties of multifaceted communication between cells and adaptation to new habitats. In this paper, we are looking for one piece of the puzzle that made the development of complex multicellular eukaryotes possible with a focus on regulation of P2B autoinhibited Ca 2+-ATPases. P2B ATPases pump Ca 2+ out of the cytosol at the expense of ATP hydrolysis, and thereby maintain a steep gradient between the extra- and intracytosolic compartments which is utilized for Ca 2+-mediated rapid cell signaling. The activity of these enzymes is regulated by a calmodulin (CaM)-responsive autoinhibitory region, which can be located in either termini of the protein, at the C-terminus in animals and at the N-terminus in plants. When the cytoplasmic Ca 2+ level reaches a threshold, the CaM/Ca 2+ complex binds to a calmodulin-binding domain (CaMBD) in the autoinhibitor, which leads to the upregulation of pump activity. In animals, protein activity is also controlled by acidic phospholipids that bind to a cytosolic portion of the pump. Here, we analyze the appearance of CaMBDs and the phospholipid-activating sequence and show that their evolution in animals and plants was independent. Furthermore, we hypothesize that different causes may have initiated the appearance of these regulatory layers: in animals, it is linked to the appearance of multicellularity, while in plants it co-occurs with their water-to-land transition.

The study's goal was to develop a spore-based paper strip biosensor for detecting ß-lactam antibiotics in milk using the enzyme induction principle. A new spore-based paper strip biosensor has been developed after important operating parameters such as spore volume, substrate volume, exposure time and temperature, and incubation time and temperature were optimised. The limit of detection for various ß-lactam antibiotics, including amoxicillin, penicillin, ampicillin, carbenicillin, cloxacillin, nafcillin, oxacillin, cephalothin, cefalexin, cefoxitin, cefazolin, and cefuroxime, was determined in milk with detection sensitivity of 1 ppb, 2 ppb, 2 ppb, 10 ppb, 10 ppb, 10 ppb, 20 ppb, 10 ppb 1000 ppb, 10 ppb 300 ppb and 100 ppb, respectively. It was also tested with other contaminants such non-ß-lactam antibiotics, pesticides, aflatoxin, heavy metals, and other chemical contaminants, and no interference was found, indicating that the created biosensor had a low rate of false positive and negative results. In comparison to the AOAC-approved CHARM-ROSA ß-lactam strip test, which identified 7 raw milk and zero pasteurised milk samples positive for ß-lactam antibiotics, the sensor was further analysed and verified using 200 raw milk and 105 pasteurised milk samples. This indicates a perfect match between our biosensor and the AOAC-approved CHARM-ROSA ß-lactam strip test. The developed spore-based paper strip biosensors are expected to be useful in the rapid and cost-effective detection of ß-lactam antibiotic residues in milk samples at the dairy farm, reception dock, and production units, respectively.

Sodium thiocyanate (NaSCN) is a naturally antibacterial component in milk, but excessive consumption of thiocyanate may cause potential risks to human health. Currently available methods for the detection of thiocyanate have some disadvantages such as poor sensitivity and high price. Here, we report a robust and cost-effective method to detect NaSCN based on paper substrates deposited with

Specification of germ cell fate depends on the asymmetric segregation of germ granules in early embryos. Now, a new paper in Development describes 'germline P-bodies', germ granules in Caenorhabditis elegans embryos, which function cooperatively with another condensate, P granules, in germline specification. To find out more, we caught up with first author Madeline Cassani and corresponding author Geraldine Seydoux, Professor at Johns Hopkins University School of Medicine.

Cellulose nanofibril (CNF) paper has various applications due to its unique advantages. Herein, we present the intrinsic mechanical properties of CNF papers, along with the preparation and properties of nanoparticle-reinforced CNF composite papers. The literature on CNF papers reveals a strong correlation between the intrafibrillar network structure and the resulting mechanical properties. This correlation is found to hold for all primary factors affecting mechanical properties, indicating that the performance of CNF materials depends directly on and can be tailored by controlling the intrafibrillar network of the system. The parameters that influence the mechanical properties of CNF papers were critically reviewed. Moreover, the effect on the mechanical properties by adding nanofillers to CNF papers to produce multifunctional composite products was discussed. We concluded this article with future perspectives and possible developments in CNFs and their bionanocomposite papers.

The theory about the infectious causes of cancer was very popular at the turn of the nineteenth and twentieth centuries. The research methodology to confirm this hypothesis was based on diagnostic methods used by bacteriology. Various types of experiments were carried out on animals and humans. Attempts were made to "infect" cancer, as well as to transplant cancer cells into healthy animals. Disinfectants were studied looking for opportunities for anti-cancer prophylaxis. They were guided by analogy and empiricism, clinical images of diseases were compared. The aim of the article is to recall research on the infectious theory of cancer with a reminder of the achievements of Polish scientists in this field, and to try to determine the genesis of this theory.

Monoclonal antibodies (mAbs) deliver great benefits to patients with chronic and/or severe diseases thanks to their strong specificity to the therapeutic target. As a result of this specificity, non-human primates (NHP) are often the only preclinical species in which therapeutic antibodies cross-react with the target. Here, we highlight the value and limitations that NHP studies bring to the design of safe and efficient early clinical trials. Indeed, data generated in NHPs are integrated with in vitro information to predict the concentration/effect relationship in human, and therefore the doses to be tested in first-in-human trials. The similarities and differences in the systems defining the pharmacokinetics and pharmacodynamics (PKPD) of mAbs in NHP and human define the nature and the potential of the preclinical investigations performed in NHPs. Examples have been collated where the use of NHP was either pivotal to the design of the first-in-human trial or, inversely, led to the termination of a project prior to clinical development. The potential impact of immunogenicity on the results generated in NHPs is discussed. Strategies to optimize the use of NHPs for PKPD purposes include the addition of PD endpoints in safety assessment studies and the potential re-use of NHPs after non-terminal studies or cassette dosing several therapeutic agents of interest. Efforts are also made to reduce the use of NHPs in the industry through the use of in vitro systems, alternative in vivo models, and in silico approaches. In the case of prediction of ocular PK, the body of evidence gathered over the last two decades renders the use of NHPs obsolete. Expert perspectives, advantages, and pitfalls with these alternative approaches are shared in this review.

Over the years, conflicting data have meant that the role of Wnt in symmetry breaking and axis formation was unclear. Now, a new paper published in Development finds that maternal Wnt11b is required for robust cortical rotation inXenopus laevis, which, in turn, is required for axis induction. To find out more about this story, we caught up with two of the authors, Douglas Houston, Professor at The University of Iowa, and Marko Horb, Director of the National Xenopus Resource at the Marine Biological Laboratory in Chicago.

Milk adulteration is a common problem in developing countries, and it can lead to fatal diseases in humans. Despite several studies to identify different adulterants in milk samples, the effects of multiple adulterants remain unexplored. In this work, a three-dimensional (3D) paper-based microfluidic device is designed and fabricated to simultaneously detect multiple chemical adulterants in milk. This device comprises a top cover, a bottom cover, and a middle layer composed of transportation and a detection zone. By making cuts on the middle layer’s support, the device’s flow path is characterised by optimum and uniform velocity. For the first time, seven adulterants (urea, detergents, soap, starch, hydrogen peroxide, sodium-hydrogen-carbonate, and salt) are detected in the milk sample simultaneously with specificity evaluation and detailed color interference analysis. Only 1–2 mL of sample volume is required to detect 7 adulterants at one time. We have used only 10 $$\upmu$$ μ L of the reagent’s volume for the colorimetric reaction and found the results within a few seconds. Observation reveals that the limit of detection (LOD) of the adulterants lies in the range between $$0.05\%$$ 0.05 % (vol./vol.) to $$0.2\%$$ 0.2 % (vol./vol.) using the colorimetric detection technique. The unknown quantity of the added adulterants is measured using the calibration curves obtained from the experiments results. The repeatability and reproducibility of the process, sensitivity, and the linear range of detection of the calibration curves and the statistical study of the color intensity data are thoroughly analysed herein. In any resource-limited setting, this simple, portable, and user-friendly 3D microfluidic device is expected to be used for testing liquid foods before consumption.

Paper wasps are a model system for the study of social evolution due to a high degree of inter- and intraspecific variation in cooperation, aggression, and visual signals of social status. Increasing the taxonomic coverage of genomic resources for this diverse clade will aid comparative genomic approaches for testing predictions about the molecular basis of social evolution. Here, we provide draft genome assemblies for two well-studied species of paper wasps, Polistes exclamans and Mischocyttarus mexicanus. The P. exclamans genome assembly is 221.5 Mb in length with a scaffold N50 of 4.11 Mb. The M. mexicanus genome assembly is 227 Mb in length with a scaffold N50 of 1.1 Mb. Genomes have low repeat content (9.54–10.75%) and low GC content (32.06–32.4%), typical of other social hymenopteran genomes. The DNA methyltransferase gene, Dnmt3 , was lost early in the evolution of Polistinae. We identified a second independent loss of Dnmt3 within hornets (genus: Vespa).

A proof of concept for using paper test as a suitable method in the production of monoclonal antibodies (MAbs) is reported. The paper test which detects antibodies against porcine circovirus type 2 (PCV2) using colloidal gold-labelled capsid protein as the antigen probe was applied exclusively in the screening of anti-PCV2 MAbs. It allowed the detection of 118 single cell clones within 30 min using naked eyes. MAbs with specific binding to authentic epitopes on the virus were selected using a blocking strategy in which the antibody was pre-incubated with PCV2 viral sample before applying to the test paper. Five hybridomas secreting MAbs against the capsid protein were obtained, with only three of them capable of binding to PCV2. The results were validated and confirmed using enzyme-linked immunosorbent assay and immunofluorescence assay. The paper test is simple, rapid, and independent on professional technicians and proves to be an excellent approach for the screening of MAbs against specific targets.

A novel strategy is presented for simple, sensitive and selective branched-chain amino acids (BCAAs) detection in edible insects on a paper test strip device readout with a smartphone. Silver nanoparticles (AgNPs) were applied, interacting with dye, which provided 1.5 times higher color intensity than the one without AgNPs. The proposed paper test strip exhibiting the detection limit of leucine, isoleucine and valine were 6.0, 6.2 and 7.2 mg/L, respectively. The linear dynamic ranges were 20-120 mg/L for leucine and 20-110 mg/L for isoleucine and valine detections. The proposed paper test strip was successfully applied for the detection of BCAAs in edible insects. The analytical results obtained using paper test strips were in good agreement with those obtained via a commercial test kit. This study shows the successful integration of the paper test strip and the smartphone to afford an easy-to-use, inexpensive and portable device alternative for BCAAs analysis.

Viral-derived genes have had a huge impact during mammalian evolution, with many of the exapted genes being expressed in the placenta. Now, new research published in Development describes the importance of two genes with retroviral origins in microglia, the innate immune cells of the brain, which are derived from another extra-embryonic tissue, the yolk sac. We caught up with the first author, Masahito Irie, and the corresponding authors, Fumitoshi Ishino, Professor at Tokyo Medical and Dental University, and Tomoko Kaneko-Ishino, Professor at Tokai University, to hear about more about their research.

Social insects are highly diverse in their social structures, aside from the consistent presence of reproductive castes. Among social insects, the Australian paper wasp Ropalidia plebeiana constructs extremely dense colony aggregations consisting of hundreds of colonies within a few square meters; however, little is known about the aggregation structures. We genetically analyzed the colony and population structure of R. plebeiana, and concomitant variations in colony sex ratios. In spring, the foundress (candidate queen) group started their colonies on a single old comb from the previous season, subsequently dividing these old combs via relatedness-based comb-cutting. Female philopatry, a prerequisite condition of Local Resource Competition (LRC), was confirmed. The colony sex ratio of reproductive individuals (male and female offspring for the next generation) became slightly male-biased in larger colonies, as predicted under LRC. However, the number of foundresses was positively associated with the number of reproductive individuals, suggesting that Local Resource Enhancement (LRE) also operates. Although the population structure appears to meet the prerequisites of LRC, the sex ratio appears to be modulated by factors other than LRC. Rather, through LRE, the availability of female helpers at the founding stage is likely to mitigate the sex ratios predicted under LRC.

Concept formation requires animals to learn and use abstract rules that transcend the characteristics of specific stimuli. Abstract concepts are often associated with high levels of cognitive sophistication, so there has been much interest in which species can form and use concepts. A key abstract concept is that of sameness and difference, where stimuli are classified as either the same as or different than an original stimulus. Here, we used a simultaneous two-item same-different task to test whether paper wasps ( Polistes fuscatus) can learn and apply a same-different concept. We trained wasps by simultaneously presenting pairs of same or different stimuli (e.g. colours). Then, we tested whether wasps could apply the concept to new stimuli of the same type (e.g. new colours) and to new stimulus types (e.g. odours). We show that wasps learned a general concept of sameness or difference and applied it to new samples and types of stimuli. Notably, wasps were able to transfer the learned rules to new stimuli in a different sensory modality. Therefore, P. fuscatus can classify stimuli based on their relationships and apply abstract concepts to novel stimulus types. These results indicate that abstract concept learning may be more widespread than previously thought.

Publishing a primary research article is typically the result of a collaborative effort between a variety of researchers across differing career stages. STAR Protocols can complement a research article and empower authors to share the expertise they contributed to the larger study. In this Backstory, we interview members of the Gennarino lab, who published a Cell paper and four protocols, covering bioinformatics, culturing of patient-derived cell lines, neuroimaging from mouse brain sections and primary neurons, and mouse seizure recordings. For more information on the protocols related to this backstory, please refer to (Gennarino et al., 2018).

Currently available European Alpine Altitude Climate Treatment (AACT) programs combine the physical characteristics of altitude with the avoidance of environmental triggers in the alpine climate and a personalized multidisciplinary pulmonary rehabilitation approach. The reduced barometric pressure, oxygen pressure, and air density, the relatively low temperature and humidity, and the increased UV radiation at moderate altitude induce several physiological and immunological adaptation responses. The environmental characteristics of the alpine climate include reduced aeroallergens such as house dust mites (HDM), pollen, fungi, and less air pollution. These combined factors seem to have immunomodulatory effects controlling pathogenic inflammatory responses and favoring less neuro-immune stress in patients with different asthma phenotypes. The extensive multidisciplinary treatment program may further contribute to the observed clinical improvement by AACT in asthma control and quality of life, fewer exacerbations and hospitalizations, reduced need for oral corticosteroids (OCS), improved lung function, decreased airway hyperresponsiveness (AHR), improved exercise tolerance, and improved sinonasal outcomes. Based on observational studies and expert opinion, AACT represents a valuable therapy for those patients irrespective of their asthma phenotype, who cannot achieve optimal control of their complex condition despite all the advances in medical science and treatment according to guidelines, and therefore run the risk of falling into a downward spiral of loss of physical and mental health. In the light of the observed rapid decrease in inflammation and immunomodulatory effects, AACT can be considered as a natural treatment that targets biological pathways. ispartof: ALLERGY vol:77 issue:7 pages:1991-2024 ispartof: location:Denmark status: published

The 3D architecture of the uterus plays a key role in determine pregnancy outcome. A new paper in Development reveals the dynamic changes in luminal folding pattern that occur during the preimplantation period in mice. To hear more about the story, we caught up with first author Manoj Madhavan and corresponding author Ripla Arora, Assistant Professor at Michigan State University.

Allergic asthma (AA) is a common asthma phenotype, and its diagnosis requires both the demonstration of IgE-sensitization to aeroallergens and the causative role of this sensitization as a major driver of asthma symptoms. Therefore, a bronchial allergen challenge (BAC) would be occasionally required to identify AA patients among atopic asthmatics. Nevertheless, BAC is usually considered a research tool only, with existing protocols being tailored to mild asthmatics and research needs (eg long washout period for inhaled corticosteroids). Consequently, existing BAC protocols are not designed to be performed in moderate-to-severe asthmatics or in clinical practice. The correct diagnosis of AA might help select patients for immunomodulatory therapies. Allergen sublingual immunotherapy is now registered and recommended for controlled or partially controlled patients with house dust mite-driven AA and with FEV1 ≥ 70%. Allergen avoidance is costly and difficult to implement for the management of AA, so the proper selection of patients is also beneficial. In this position paper, the EAACI Task Force proposes a methodology for clinical BAC that would need to be validated in future studies. The clinical implementation of BAC could ultimately translate into a better phenotyping of asthmatics in real life, and into a more accurate selection of patients for long-term and costly management pathways.

This work aimed to reveal the differences of nitrogen (N) transformation between animal-derived and plant-derived biochar during paper mill sludge composting. Three treatments were established, including CK (no biochar), ABC (animal-derived biochar), and PBC (plant-derived biochar). Results showed that N loss was reduced by 24.43% and 35.50% in ABC and PBC, respectively, compared with CK. Moreover, the contents of acid-insoluble N (AIN) in ABC and bioavailable organic N (BON) in PBC were 6.180 g/kg and 9.269 g/kg higher than in CK (2.602 g/kg and 8.988 g/kg). The protease activity and bacterial abundance associated with the generation of humic N-containing precursors increased in ABC. Low urease activity and a more complex bacterial N-cycling network were found in PBC. Structural equation model confirmed that AIN formation and BON retention were the dominant strategies for animal-derived and plant-derived biochar, respectively. The findings provided multiple pathways to produce N-enriched compost products.

The paper by K. L. Blaxter and J. L. Clapperton (1965) 'Prediction of the amount of methane produced by ruminants.

Although in a critical position in the economy, the paper industry releases a lot of wastewater that requires adequate treatment for sustainable development. This study presents an application of Life cycle assessment (LCA) with the ReCiPe tool on the wastewater treatment plant (WWTP) of a paper factory in Vietnam to evaluate the environmental effect of the individual techniques in WWTP, especially the internal circulation (IC) reactor, a pioneer and practical anaerobic technology. Both Midpoint and Endpoint categories results demonstrated that chemical use and electricity consumption mainly contributed to the environmental impact in the WWTP. The Dissolved air flotation (DAF) and Moving bed biofilm reactor (MBBR) are classified as effective techniques to reduce the impacts on the environment. Moreover, the comparison of LCA between IC and up-flow anaerobic sludge bed (UASB) shows that IC is the better practically green technique for the environment.

The deposition of trace elements around a pulp and paper industry in Morelia, Mexico, was evaluated using two lichen species as biomonitors. Samples of the foliose lichen Flavopunctelia praesignis and the fruticose lichen Usnea ceratina were collected in two remote areas and transplanted at different distances and directions from the pollution source. Lichen samples were exposed for 4 months (1) around the industrial area and (2) in their native habitats (control sites). We investigated the bioaccumulation of 11 trace elements in lichen thalli, and we compared the response of the two lichen species. To identify possible common sources, we evaluated the relationships between trace elements by correlations and cluster analyses. Our results showed that Cd was a good tracer for air pollution from the pulp and paper mills. In samples of Usnea ceratina exposed around the industrial area, Cd was significantly higher than in the remote area. Within the study area, trace element contents increase with the distance from the source, and they showed high depositions in the direction of prevailing winds. Moreover, we were able to detect groups of elements with similar behavior and common origins. Our results indicated that Flavopunctelia praesignis showed a higher capacity to accumulate trace elements than Usnea ceratina.

Specification of primordial germ cells requires a proportion of the cells in the posterior of the epiblast to reacquire pluripotency. A new paper in Development describes how OVOL2 is involved in regulating the balance between mesodermal fate and germ cell fate during gastrulation. We caught up with the first author, Yuki Naitou, and corresponding author, Katsuhiko Hayashi (Osaka University), to find out more about the paper and their future research.

Herein, we present for the first time, the employment of paper-based devices for rapidly differentiating original country eggs from the plain broiler eggs that have been coated with tea to appear as the former. The devices leverage two types of phenomena involving the phenols present in tea in precisely 5 min, namely precipitation, which produces a well-defined dark bluish precipitate on the surface of the counterfeit country eggs or tea-coated broiler eggs and de-coloration, wherein the dried layer of tea coating present on the surface of the dummy country eggs get dissolved, thereby revealing the white colour of the plain broiler egg shell. To reduce the subjectivity, a smartphone application 'Eggo' has been developed which is capable of detecting the spots produced by both the methods using mobile's camera. Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed to study the changes occurring on the shell surface. Such sophisticated yet simple technologies will revolutionize food fraud analysis.

In this study, a paper-based enzyme biosensor for hypoxanthine (Hx) was developed, enabling visual and one-step fish freshness detection. Xanthine oxidase and horseradish peroxidase were immobilized on nitrocellulose membranes with 3,3',5,5'-tetramethylbenzidine to output the colour signal. Chitosan oligosaccharide lactate-modified nitrocellulose membranes entrapped the dual-enzyme system and exhibited excellent microfluidic aggregation effect. The developed enzyme biosensor produced a linear response of 0.01-0.16 mmolL

Access to low-burden molecular diagnostics that can be deployed into the community for testing is increasingly important and has meaningful wider implications for the well-being of societies and economic stability. Recent years have seen several new isothermal diagnostic modalities emerge to meet the need for rapid, low-cost molecular diagnostics. We have contributed to this effort through the development and patient validation of toehold switch-based diagnostics, including diagnostics for the mosquito-borne Zika and chikungunya viruses, which provided performance comparable to gold-standard reverse transcription-quantitative polymerase chain reaction (RT-qPCR) based assays. These diagnostics are inexpensive to develop and manufacture, and they have the potential to provide diagnostic capacity to low-resource environments. Here the protocol provides all the steps necessary for the development of a switch-based assay for Zika virus detection. The article takes readers through the stepwise diagnostic development process. First, genomic sequences of Zika virus serve as inputs for the computational design of candidate switches using open-source software. Next, the assembly of the sensors for empirical screening with synthetic RNA sequences and optimization of diagnostic sensitivity is shown. Once complete, validation is performed with patient samples in parallel with RT-qPCR, and a purpose-built optical reader, PLUM. This work provides a technical roadmap to researchers for the development of low-cost toehold switch-based sensors for applications in human health, agriculture, and environmental monitoring.