Transmission Stages Research Articles

A Comprehensive Analysis: Evaluating Security Characteristics of Xbee Devices against Zigbee Protocol.

In recent times, the security of sensor networks, especially in the field of IoT, has become a priority. This article focuses on the security features of the Zigbee protocol in Xbee devices developed by Digi International, specifically in the Xbee 3 (XB3-24) devices. Using the TI LaunchXL-CC26X2R1 kit, we intercepted and analyzed packets in real-time using the Wireshark application. The study encompasses various stages of network formation, packet transmission and analysis of security key usage, considering scenarios as follows: without security, distributed security mode and centralized security mode. Our findings highlight the differences in security features of Xbee devices compared to the Zigbee protocol, validating and invalidating methods of establishing security keys, vulnerabilities, strengths, and recommended security measures. We also discovered that security features of the Xbee 3 devices are built around a global link key preconfigured therefore constituting a vulnerability, making those devices suitable for man-in-the-middle and reply attacks. This work not only elucidates the complexities of Zigbee security in Xbee devices but also provides direction for future research for authentication methods using asymmetric encryption algorithms such as digital signature based on RSA and ECDSA.

High glucose exposure of preimplantation embryos causes glucose intolerance and insulin resistance in F1 and F2 male offspring

BackgroundAlthough studies suggest that maternal high glucose (HG) increases offspring susceptibility to type 2 diabetes mellitus (T2DM), the underlying mechanisms are largely unclear. We studied whether glucose levels in oviducts are elevated when pregestational diabetic females get pregnant and whether the oviductal HG (OVHG) would act directly on embryos to increase offspring's T2DM susceptibility. MethodsWe established an in vivo model of OVHG by injecting female mice with streptozotocin (STZ) during the preimplantation period and an in vitro model of embryo culture with HG (ECHG) by culturing preimplantation embryos with HG, before examining glucose tolerance and insulin resistance (IR) in F1 and F2 offspring. FindingsInjection of female mice with STZ induced a lasting significant glucose elevation in blood and oviduct fluid during the preimplantation period. The glucose tolerance test showed that both the STZ-induced OVHG and the ECHG caused glucose intolerance in F1 male and F1-sired F2 male offspring but had no effect on female offspring. Insulin tolerance test and the analysis for IR-related gene expression and glycogen contents in liver and muscle revealed significant IR in these male offspring. InterpretationThis study provided evidence that HG can act directly on preimplantation embryos to increase offspring's T2DM susceptibility suggesting that the preimplantation period is a critical stage for transmission of mother's diabetes to offspring. FundThis study was supported by grants from the China National Natural Science Foundation (Nos. 31772599, 32072738, 31702114, and 31902160), and the Natural Science Foundation of Shandong Province (Nos. ZR2022MC036, ZR2017BC025 and ZR2020QC102).

Insight Into the Dynamics of the Ixodes ricinus Nymphal Midgut Proteome

Ticks are ectoparasites that feed on blood and have an impressive ability to consume and process enormous amounts of host blood, allowing extremely long periods of starvation between blood meals. The central role in the parasitic lifestyle of ticks is played by the midgut. This organ efficiently stores and digests ingested blood and serves as the primary interface for the transmission of tick-borne pathogens. In this study, we used a label-free quantitative approach to perform a novel dynamic proteomic analysis of the midgut of Ixodesricinus nymphs, covering their development from unfed to pre-molt stages. We identified 1534 I.ricinus-specific proteins with a relatively low proportion of host proteins. This proteome dataset, which was carefully examined by manual scrutiny, allowed precise annotation of proteins important for blood meal processing and their dynamic changes during nymphal ontogeny. We focused on midgut molecules related to lipid hydrolysis, storage, and transport, opening a yet unexplored avenue for studying lipid metabolism in ticks. Further dynamic profiling of the tick's multi-enzyme digestive network, protease inhibitors, enzymes involved in redox homeostasis and detoxification, antimicrobial peptides, and proteins responsible for midgut colonization by Borrelia spirochetes promises to uncover new targets for targeting tick nymphs, the most critical life stage for transmission the pathogens that cause tick-borne diseases.

Zika virus diversity in mice is maintained during early vertical transmission from placenta to fetus, but reduced in fetal bodies and brains at late stages of infection.

Since emerging in French Polynesia and Brazil in the 2010s, Zika virus (ZIKV) has been associated with fetal congenital disease. Previous studies have compared ancestral and epidemic ZIKV strains to identify strain differences that may contribute to vertical transmission and fetal disease. However, within-host diversity in ZIKV populations during vertical transmission has not been well studied. Here, we used the established anti-interferon treated Rag1-/- mouse model of ZIKV vertical transmission to compare genomic variation within ZIKV populations in matched placentas, fetal bodies, and fetal brains via RNASeq. At early stages of vertical transmission, the ZIKV populations in the matched placentas and fetal bodies were similar. Most ZIKV single nucleotide variants were present in both tissues, indicating little to no restriction in transmission of ZIKV variants from placenta to fetus. In contrast, at later stages of fetal infection there was a sharp reduction in ZIKV diversity in fetal bodies and fetal brains. All fetal brain ZIKV populations were comprised of one of two haplotypes, containing either a single variant or three variants together, as largely homogenous populations. In most cases, the dominant haplotype present in the fetal brain was also the dominant haplotype present in the matched fetal body. However, in two of ten fetal brains the dominant ZIKV haplotype was undetectable or present at low frequencies in the matched placenta and fetal body ZIKV populations, suggesting evidence of a strict selective bottleneck and possible selection for certain variants during neuroinvasion of ZIKV into fetal brains.

Preserving Privacy in Industrial IoT: A Machine Learning Framework Enhanced by Poly1305 Encryption

Abstract: The convergence of Industrial Internet of Things (IoT) systems and machine learning has ushered in new paradigms for predictive maintenance, anomaly detection, and quality control in industrial sectors. Though, the sensitive nature of data generated by IoT devices raises significant privacy and security concerns. To address these challenges, this review paper presents a thorough examination of safeguarding privacy machine learning frameworks in the context of Industrial IoT environments, leveraging the robust Poly1305 encryption algorithm. This paper commences by surveying the landscape of Industrial IoT applications, highlighting the urgency of safeguarding sensitive data without compromising the potential insights gleaned from machine learning models. It then delves into the intricacies of Poly1305 encryption, elucidating its strengths in ensuring data integrity, authenticity, and confidentiality. The integration of Poly1305 encryption within machine learning pipelines is explored, considering encryption at data collection, transmission, storage, and analysis stages. The review systematically analyses a spectrum of data learning models deployed in Industrial IoT scenarios, spanning predictive maintenance to quality enhancement. Each model's compatibility with Poly1305 encryption is assessed, along with performance implications and security guarantees. The paper navigates through key obstacles including key management, computational overhead, and interoperability concerns. In summation, this review paper not only serves as a comprehensive guide for researchers and practitioners in the realm of Industrial IoT and machine learning but also contributes to the ongoing discourse on safeguarding data privacy while harnessing the transformative power of data-driven insights

Subtle transcriptomic response of Eurasian perch (Perca fluviatilis) associated with Triaenophorus nodulosus plerocercoid infection

Determining the physiological effects of parasites and characterizing genes involved in host responses to infections are essential to improving our understanding of host-parasite interactions and their ecological and evolutionary consequences. This task, however, is complicated by high diversity and complex life histories of many parasite species. The use of transcriptomics in the context of wild-caught specimens can help ameliorate this by providing both qualitative and quantitative information on gene expression patterns in response to parasites in specific host organs and tissues. Here, we evaluated the physiological impact of the widespread parasite, the pike tapeworm (Triaenophorus nodulosus), on its second intermediate host, the Eurasian perch (Perca fluviatilis). We used an RNAseq approach to analyse gene expression in the liver, the target organ of T. nodulosus plerocercoids, and spleen which is one of the main immune organs in teleost fishes. We compared perch collected from multiple lakes consisting of individuals with (n = 8) and without (n = 6) T. nodulosus plerocercoids in the liver. Results revealed a small number of differentially expressed genes (DEGs, adjusted p-value ≤0.05) in both spleen (n = 22) and liver (n = 10). DEGs in spleen consisted of mostly upregulated immune related genes (e.g., JUN, SIK1, THSB1), while those in the liver were often linked to metabolic functions (e.g., FABP1, CADM4, CDAB). However, Gene Ontology (GO) analysis showed lack of functional enrichment among DEGs. This study demonstrates that Eurasian perch displays a subtle response at a gene expression level to T. nodulosus plerocercoid infection. Given that plerocercoids are low-metabolic activity transmission stages, our results suggest that moderate T. nodulosus plerocercoid infection most likely does not provoke an extensive host immune response and have relatively low physiological costs for the host. Our findings illustrate that not all conspicuous infections have severe effects on host gene regulation.

Warmer temperatures reduce the transmission of a virus in a gregarious forest insect.

Understanding how climate warming will influence species interactions is a key question in ecology and predicting changes in the prevalence of disease outbreaks is particularly challenging. Ectotherms are likely to be more influenced by climatic changes as temperature governs their growth, feeding, development, and behavior. We test the hypothesis that pathogen transmission and host mortality will increase at warmer temperatures using a cyclic forest insect, the western tent caterpillar (WTC), Malacosoma californicum pluviale, and its baculovirus. The virus causes population declines at peak host density. WTC are gregarious and clustering is predicted to increase the risk of within family infection; however, how temperature influences this has not been examined. We investigated the impact of temperature on different components of the transmission process in order to pinpoint the possible mechanisms involved. In the laboratory, leaf consumption increased linearly with rising temperature between 15 and 30°C. Insects died more rapidly from virus infection as temperature increased, but this did not translate into differences in the production of viral transmission stages. To examine the influence of temperature on virus transmission, we created a temperature difference between two greenhouses containing potted red alder trees, Alnus rubra. The cooler greenhouse (mean 19.5°C) was roughly similar to ambient temperatures in the field, while the warmer greenhouse was 10°C higher (mean 29°C). As predicted, both larval movement and feeding were higher at the warmer temperature, while the likelihood of the preinfected, inoculum larvae dying on the tents was twice as high in the cooler greenhouse. This resulted in increased virus mortality and a higher transmission parameter under cooler conditions. Therefore, we suggest that, contrary to our prediction, the reduced movement of infected larvae at colder temperatures increased the risk of infection in these gregarious insects and had a greater impact on virus transmission than the increased activity of the susceptible larvae in warmer conditions. Long-term population data from the field, however, show no relationship between temperature and infection levels, suggesting that local changes in virus transmission might not scale up to population infection levels.

Plasmodium ARK2 and EB1 drive unconventional spindle dynamics, during chromosome segregation in sexual transmission stages

The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities by distinct protein scaffolds. Plasmodium spp., the causative agents of malaria, are unicellular eukaryotes with three unique and highly divergent aurora-related kinases (ARK1-3) that are essential for asexual cellular proliferation but lack most canonical scaffolds/activators. Here we investigate the role of ARK2 during sexual proliferation of the rodent malaria Plasmodium berghei, using a combination of super-resolution microscopy, mass spectrometry, and live-cell fluorescence imaging. We find that ARK2 is primarily located at spindle microtubules in the vicinity of kinetochores during both mitosis and meiosis. Interactomic and co-localisation studies reveal several putative ARK2-associated interactors including the microtubule-interacting protein EB1, together with MISFIT and Myosin-K, but no conserved eukaryotic scaffold proteins. Gene function studies indicate that ARK2 and EB1 are complementary in driving endomitotic division and thereby parasite transmission through the mosquito. This discovery underlines the flexibility of molecular networks to rewire and drive unconventional mechanisms of chromosome segregation in the malaria parasite.

Spread the Word: Secondary Crisis Communication of Unethical Destination Incidents via Social Media

The communication of unethical destination incidents (UDIs) through social media can be quite complex. Interestingly, the relationship between information forms of UDIs and users’ online behavior has been grossly ignored, especially in the case of secondary crisis communication (SCC). We investigate the heterogeneous impact of UDIs’ information forms on SCC rooted in the Defleur model of communication. Results from three experimental studies revealed that UDIs in video form elicit higher levels of presence and SCC than those in image-text and text forms. Risk perception and anger are important guiding factors in this process. In brief, the diffusion process of UDIs includes the three stages of reception, transformation, and transmission. The study’s findings suggest a new perspective for understanding destination crisis communication and offer practical implications for alleviating the negative impact of destination crisis.

Joint CFO and Channel Estimation for RIS-Aided Multi-User Massive MIMO Systems

Accurate channel estimation is essential to achieve the performance gains promised by the use of reconfigurable intelligent surfaces (RISs) in wireless communications. In the uplink of multi-user orthogonal frequency division multiple access (OFDMA) systems, synchronization errors such as carrier frequency offsets (CFOs) can significantly degrade the channel estimation performance. This becomes more critical in RIS-aided communications, as the RIS phases are adjusted based on the channel estimates and even a small channel estimation error leads to a significant performance loss. Motivated by this, we propose a joint CFO and channel estimation method for RIS-aided multi-user massive multiple-input multiple-output (MIMO) systems. Our proposed pilot structure makes it possible to accurately estimate the CFOs without multi-user interference (MUI), using the same pilot resources for both CFO estimation and channel estimation. For optimization of the RIS phase shifts at the data transmission stage, we propose a projected gradient method (PGM) which achieves the same performance as a more computationally demanding grid search technique while having a significantly lower computational complexity. Simulation results demonstrate that the proposed method provides an improvement in the normalized mean-square error (NMSE) of channel es-timation as well as in the bit error rate (BER) performance. Moreover, analyzing the computational complexity and the pilot resource efficiency of the proposed method, we demonstrate that the proposed estimation approach requires low computational load and no extra cost in pilot overhead.

Transfection Models to Investigate Plasmodium vivax-Type Dormant Liver Stage Parasites.

Plasmodium vivax causes the second highest number of malaria morbidity and mortality cases in humans. Several biological traits of this parasite species, including the formation of dormant stages (hypnozoites) that persist inside the liver for prolonged periods of time, present an obstacle for intervention measures and create a barrier for the elimination of malaria. Research into the biology of hypnozoites requires efficient systems for parasite transmission, liver stage cultivation and genetic modification. However, P. vivax research is hampered by the lack of an in vitro blood stage culture system, rendering it reliant on in vivo-derived, mainly patient, material for transmission and liver stage culture. This has also resulted in limited capability for genetic modification, creating a bottleneck in investigations into the mechanisms underlying the persistence of the parasite inside the liver. This bottleneck can be overcome through optimal use of the closely related and experimentally more amenable nonhuman primate (NHP) parasite, Plasmodium cynomolgi, as a model system. In this review, we discuss the genetic modification tools and liver stage cultivation platforms available for studying P. vivax persistent stages and highlight how their combined use may advance our understanding of hypnozoite biology.

Plasmodium falciparum formins are essential for invasion and sexual stage development

The malaria parasite uses actin-based mechanisms throughout its lifecycle to control a range of biological processes including intracellular trafficking, gene regulation, parasite motility and invasion. In this work we assign functions to the Plasmodium falciparum formins 1 and 2 (FRM1 and FRM2) proteins in asexual and sexual blood stage development. We show that FRM1 is essential for merozoite invasion and FRM2 is required for efficient cell division. We also observed divergent functions for FRM1 and FRM2 in gametocyte development. Conditional deletion of FRM1 leads to a delay in gametocyte stage progression. We show that FRM2 controls the actin and microtubule cytoskeletons in developing gametocytes, with premature removal of the protein resulting in a loss of transmissible stage V gametocytes. Lastly, we show that targeting formin proteins with the small molecule inhibitor of formin homology domain 2 (SMIFH2) leads to a multistage block in asexual and sexual stage parasite development.

Combining a parsimonious mathematical model with infection data from tailor-made experiments to understand environmental transmission

Although most infections are transmitted through the environment, the processes underlying the environmental stage of transmission are still poorly understood for most systems. Improved understanding of the environmental transmission dynamics is important for effective non-pharmaceutical intervention strategies. To study the mechanisms underlying environmental transmission we formulated a parsimonious modelling framework including hypothesised mechanisms of pathogen dispersion and decay. To calibrate and validate the model, we conducted a series of experiments studying distance-dependent transmission of Campylobacter jejuni in broilers. We obtained informative simultaneous estimates for all three model parameters: the parameter of C. jejuni inactivation, the diffusion coefficient describing pathogen dispersion, and the transmission rate parameter. The time and distance dependence of transmission in the fitted model is quantitatively consistent with marked spatiotemporal patterns in the experimental observations. These results, for C. jejuni in broilers, show that the application of our modelling framework to suitable transmission data can provide mechanistic insight in environmental pathogen transmission.

Delftia tsuruhatensis TC1 symbiont suppresses malaria transmission by anopheline mosquitoes.

Malaria control demands the development of a wide range of complementary strategies. We describe the properties of a naturally occurring, non-genetically modified symbiotic bacterium, Delftia tsuruhatensis TC1, which was isolated from mosquitoes incapable of sustaining the development of Plasmodium falciparum parasites. D. tsuruhatensis TC1 inhibits early stages of Plasmodium development and subsequent transmission by the Anopheles mosquito through secretion of a small-molecule inhibitor. We have identified this inhibitor to be the hydrophobic molecule harmane. We also found that, on mosquito contact, harmane penetrates the cuticle, inhibiting Plasmodium development. D. tsuruhatensis TC1 stably populates the mosquito gut, does not impose a fitness cost on the mosquito, and inhibits Plasmodium development for the mosquito's life. Contained field studies in Burkina Faso and modeling showed that D. tsuruhatensis TC1 has the potential to complement mosquito-targeted malaria transmission control.

STATUS OF URBAN HEALTH INFRASTRUCTURE TO COMBAT COVID-19 IN BIRBHUM DISTRICT, WEST BENGAL

The outbreak of Covid-19 was declared a Public Health Emergency of International Concern on 31st January, 2020. Every country can take at national, sub regional and local levels to reorganize essential health services in the pandemic context and maintain a safe access to every citizen. To deal with this catastrophic Corona Virus India is making preparedness with its high urban population density, deficiency in hygiene and sanitation facilities and most crucially insufficient treatment capacity. The first 2000 cases were reported in 56 days. The next 2000 in 15 days and the next 2000 cases in a week. According to the data released by the state health department, West Bengal took just 5 days from June 3 rd to June 7th to register the next 2000 cases. Till Tuesday (9th June) total cases in the state stood at 8985. With increased number of testing and the entry of migrant labourers, there was a sudden spike in the number of cases. The returning migrant workers from the highly infected zones after an unplanned lockdown delivers a major catastrophe at our doorstep. The objective of the study is to focus on the arrangement of health services for this disaster in Birbhum District, West Bengal. According to the direction of the Bengal health department, separate hospitals for Covid-19 patients are to be set up in each district in order to arrange a local set-up before the contamination expands into the community transmission stage.

The evaluation of electrical circuits for adjusting sound transmission properties of piezoelectric metamaterials

In rods and beams, piezoelectric patches with external circuits have been extensively studied to dampen structural vibrations at the sound source. This work uses a large flat-layer type of piezoelectric acoustic metamaterial (AM) model for noise attenuation in the sound transmission stage rather than at the sound source. This could be directly implemented as a large space sound transmission barrier at the interface of diverse media including gas, liquid, and solid materials. The general analytical model to derive acoustic properties of the piezoelectric acoustic metamaterial is established by the equivalent transfer matrix approach for normal incidence waves. This has been validated numerically using the finite element method and experimentally in the solid medium propagation for the first time. Moreover, a parametric study of sound transmission properties in air, water, and steel is conducted by adjusting external circuit parameters, flat-layer structures, and piezoelectric materials. The findings demonstrate the ability to control sound resonance frequency and bandwidth through the propagation process over a wide range using external circuit parameters alone. This endows the piezoelectric acoustic metamaterial with great versatility relative to conventional, fixed structure, metamaterials used as sound barriers at the interface of diverse media. In addition, the size of the piezoelectric AM can reach a deeply sub-wavelength level, less than 10−3 of the resonance wavelength in both water and solid media, which goes far beyond the wavelength-to-thickness ratio of classical acoustic metamaterials. The layer-type piezoelectric AM thus shows excellent performance in tunability and compactness for space-sensitive applications as well as great potential in combining metamaterials with electronic control.

Mathematical Modelling of Transmission of Covid-19 in Indian Context: An Impact of Lockdown

Mathematical Modelling study has been carried out to model the out spread of Covid-19 in a localized society of India. Based on the transmission mechanism of Covid-19 authors established dynamics model of six chambers with population birth rate and mortality. Ordinary differential equations are used to model the system mathematically and solved numerically using ODE23 scheme. India imposes lockdown in very early stage of the Covid-19 transmission and impact of lockdown has been discussed through the mathematical model. Parameters are considered in view of the March scenario in India and the impact we got is quite similar with the present situation.

실업계고 농악(農樂) 전문교육이 남긴 의미와 고등교육 단계 농악 교육의 방향

Since the establishment of the Korean government, Gugak has entered institutional education. Attention was paid to this aspect because it shows that professional Korean traditional music education, which relied on apprenticeship education in the past, began within a modern and contemporary educational institution called “school.” Starting with high school education in the early 1950s, Korean traditional music education has been upgraded to higher education in universities over time. And as time went by, the number of professional education institutions also increased. But, it was only just before the 21st century that folk arts such as folk songs and folk games, including Nongak, entered higher education. Instead of higher educational institutes, in vocational high schools specialized Nongak education, which had been away from the center of education since the middle of 1950. It is clear that this phenomenon must be explored to shed light on changes in modern Nongak history and Korean traditional music education. This is because figures trained through Nongak education in the vocational high school space are currently actively participating in the transmission, performance, and education of Nongak in each region and have a significant impact on the current stage of Nongak transmission.

Heme promotes sexual conversion of Plasmodium falciparum in human erythrocytes

Between 2018 and 2020, the global population experienced a 55% increase in deaths attributed to the most prominent malaria-causing pathogen, Plasmodium falciparum. Transmission of P. falciparum from a human host to the mosquito vector is completely reliant on the formation of sexual stage gametocytes, which arise from asexually replicating parasites during the intraerythrocytic stage of infection. Defining specific factors that promote the formation of transmissible sexual stages from the disease-causing asexual stages is important for developing new malaria control methods. Malaria infection rates are known to be affected by genetic variation of the hemoglobin (Hb) protein, and epidemiological studies have shown that Hb variants may positively influence the production of sexual stage parasites. However, the mechanisms involved are poorly defined. Here, we show P. falciparum sexual conversion rates (SCR) are significantly higher in erythrocytes expressing Hb S compared to those that express Hb A. We then found parasitic enzyme-mediated digestion of Hb S to occur more rapidly than Hb A, suggesting an increased release of heme groups carried by each Hb subunit. Upon manipulating both intracellular and extracellular heme concentrations, we found significant increases in SCR, ultimately indicating heme acts as an inducer of sexual conversion (SC). As levels of both intracellular and extracellular heme are increased in individuals with Hb variants, we propose heme to be a contributing factor for increased sexual stage conversion observed in these populations. These findings support further investigation into how heme concentrations may be directly manipulated to prevent commitment to sexual-stage formation and ultimately disease transmission.

Amplicon sequencing allows differential quantification of closely related parasite species: an example from rodent Coccidia (Eimeria)

BackgroundQuantifying infection intensity is a common goal in parasitological studies. We have previously shown that the amount of parasite DNA in faecal samples can be a biologically meaningful measure of infection intensity, even if it does not agree well with complementary counts of transmission stages (oocysts in the case of Coccidia). Parasite DNA can be quantified at relatively high throughput using quantitative polymerase chain reaction (qPCR), but amplification needs a high specificity and does not simultaneously distinguish between parasite species. Counting of amplified sequence variants (ASVs) from high-throughput marker gene sequencing using a relatively universal primer pair has the potential to distinguish between closely related co-infecting taxa and to uncover the community diversity, thus being both more specific and more open-ended.MethodsWe here compare qPCR to the sequencing-based amplification using standard PCR and a microfluidics-based PCR to quantify the unicellular parasite Eimeria in experimentally infected mice. We use multiple amplicons to differentially quantify Eimeria spp. in a natural house mouse population.ResultsWe show that sequencing-based quantification has high accuracy. Using a combination of phylogenetic analysis and the co-occurrence network, we distinguish three Eimeria species in naturally infected mice based on multiple marker regions and genes. We investigate geographical and host-related effects on Eimeria spp. community composition and find, as expected, prevalence to be largely explained by sampling locality (farm). Controlling for this effect, the novel approach allowed us to find body condition of mice to be negatively associated with Eimeria spp. abundance.ConclusionsWe conclude that amplicon sequencing provides the underused potential for species distinction and simultaneous quantification of parasites in faecal material. The method allowed us to detect a negative effect of Eimeria infection on the body condition of mice in the natural environment.Graphical