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    I spy with my speedy eye — scientists discover speed of visual perception ranges widely in humans

    Using a blink-and-you’ll-miss-it experiment, researchers from Trinity College Dublin have discovered that individuals differ widely in the rate at which they perceive visual signals. Some people perceive a rapidly changing visual cue at frequencies that others cannot, which means some access more visual information per timeframe than others.
    This discovery suggests some people have an innate advantage in certain settings where response time is crucial, such as in ball sports, or in competitive gaming.
    The rate with which we perceive the world is known as our “temporal resolution,” and in many ways it is similar to the refresh rate of a computer monitor.
    The researchers, from the Department of Zoology in the School of Natural Sciences and the Trinity College Institute of Neuroscience, found that there is considerable variation among people in their temporal resolution, meaning some people effectively see more “images per second” than others.
    To quantify this, the scientists used the “critical flicker fusion threshold,” a measure for the maximum frequency at which an individual can perceive a flickering light source.
    If the light source flickers above a person’s threshold, they will not be able to see that it is flickering, and instead see the light as steady. Some participants in the experiment indicated they saw the light as completely still when it was in fact flashing about 35 times per second, while others were still able to perceive the flashing at rates of over 60 times per second.
    Clinton Haarlem, PhD Candidate in the School of Natural Sciences, is the first author of the article that has just been published in leading journal PLOS ONE. He said: “We also measured temporal resolution on multiple occasions in the same participants and found that even though there is significant variation among individuals, the trait appears to be quite stable over time within individuals.”
    Though our visual temporal resolution is quite stable from day to day in general, a post-hoc analysis did suggest that there may be slightly more variation over time within females than within males.

    “We don’t yet know how this variation in visual temporal resolution might affect our day-to-day lives, but we believe that individual differences in perception speed might become apparent in high-speed situations where one might need to locate or track fast-moving objects, such as in ball sports, or in situations where visual scenes change rapidly, such as in competitive gaming,” added Clinton Haarlem.
    “This suggests that some people may have an advantage over others before they have even picked up a racquet and hit a tennis ball, or grabbed a controller and jumped into some fantasy world online.”
    Andrew Jackson, Professor in Zoology in Trinity’s School of Natural Sciences, said: “What I think is really interesting about this project is how a zoologist, a geneticist and a psychologist can all find different angles to this work. For me as a zoologist the consequences of variation in visual perception likely has profound implications for how predators and prey interact, with various arms-races existing for investment in brain processing power and clever strategies to exploit weaknesses in one’s enemy.”
    Kevin Mitchell, Associate Professor in Developmental Neurobiology in Trinity’s School of Genetics and Microbiology, and the Trinity College Institute of Neuroscience, said: “Because we only have access to our own subjective experience, we might naively expect that everyone else perceives the world in the same way we do. Examples like colour blindness show that isn’t always true, but there are many less well known ways that perception can vary too. This study characterises one such difference — in the ‘frame rate”‘ of our visual systems. Some people really do seem to see the world faster than others.” More

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    Study uses artificial intelligence to show how personality influences the expression of our genes

    An international study led by the UGR using artificial intelligence has shown that our personalities alter the expression of our genes. The findings shed new light on the long-standing mystery of how the mind and body interact.
    The study, published in the journal Molecular Psychiatry (Nature), examines how an individual’s personality and underlying outlook on life regulate their gene expression, and thus affect their health and well-being. It is the first study to measure the transcription of the entire genome in relation to human personality.
    The multi- and interdisciplinary study was led by researchers from the Andalusian Interuniversity Research Institute in Data Science and Computational Intelligence (DaSCI), the UGR’s Department of Computer Science and Artificial Intelligence, and the Biohealth Research Institute in Granada (ibs.GRANADA). It was carried out in collaboration with Professor Robert Cloninger (Washington University in St. Louis), researchers from Baylor College of Medicine (Texas, USA) and the Young Finns Study (Finland).
    The international research team (made up of specialists in genetics, medicine, psychology and computer science) used data from the Young Finns Study, an extensive study conducted in the general population of Finland over four decades during which relevant information was collected on participants’ health, physical condition and lifestyle. In addition, participants were subjected to extensive personality assessments that addressed both temperament (habits and emotional reactivity) and character (conscious goals and values). The results showed that certain outlooks on life are conducive to a healthy, fulfilling and long life, while others lead to a stressful, unhealthy and short life.
    The study analysed the regulation of gene expression in these individuals, taking into account three levels of self-awareness that were measured through their combined temperament and character profiles. These levels were designated “unregulated” — individuals dominated by irrational emotions and habits associated with their traditions and obedience to authority, “organised” — self-sufficient individuals capable of intentionally regulating their habits and cooperating with others for mutual benefit, and lastly, “creative” — self-transcendent individuals who adapt their habits to live in harmony with others, with nature or with the universe, even if this requires occasional personal sacrifices.
    Two key findings
    As UGR researcher and co-lead author of the study Coral del Val explains: “In our research we made two key discoveries about the expression and organisation of genes according to the personality profiles of these individuals. First, we discovered a network of 4,000 genes that clustered into multiple modules that were expressed in specific regions of the brain. Some of these genes had already been linked in previous studies to the inheritance of human personality. Second, we discovered that the modules formed a functional interaction network capable of orchestrating changes in gene expression in order to adapt to varying internal and external conditions. The modules turned on and off in a flexible manner, facilitating adaptation to the everyday challenges we all face, and choreographing our development.”
    The researchers showed that the changes in the patterns of interaction between these modules were orchestrated by two sub-networks. One network regulated emotional reactivity (anxiety, fear, etc.), while the other regulated what a person perceives as meaningful (e.g. production of concepts and language). “What’s most remarkable is the fact that the networks for emotion and meaning are coordinated by a control centre made up of six genes,” notes Elisa Díaz de la Guardia-Bolívar, the other co-lead author of the study. “It is particularly interesting that we found that the six genes of the control hub are highly preserved throughout evolution, from single-celled organisms to modern humans. This finding confirms their beneficial role in regulating the functioning of all forms of life on Earth,” she adds.

    Identifying these gene networks and the control hub regulating gene expression in humans has practical value because it shows how people can improve the quality of their health, happiness and overall quality of daily life, despite the challenges and stresses we all face.
    The UGR’s Igor Zwir explains: “In previous research, we found significant differences in well-being between people in the three personality groups, depending on their level of self-awareness. Specifically, those with greater self-awareness (the creative group) reported greater well-being compared to the organised and unregulated groups. We have now shown that these levels of self-awareness are also strongly associated with the regulation of gene expression in the same order (creative > organised > unregulated). This suggests that a person can improve their health and well-being by cultivating a more self-transcendent and creative outlook on life.”
    However, he cautions that it remains to be confirmed whether the regulation of gene expression through interventions that enhance self-awareness is the mediating factor in the association between self-awareness and well-being. Nevertheless, treatments that promote greater self-transcendence and mindfulness have also been shown to contribute to improvements in all aspects of health, including physical, mental, social and spiritual well-being. It is therefore plausible that the regulation of gene expression is the real mediator in this association.
    As the researchers predicted, certain types of genes, such as transcription factors, microRNAs and long non-coding RNAs, showed extensive enrichment in the 4000-gene integrated molecular network. However, the most significant enrichment was observed in a group of RNAs that are thought to have played a crucial role in the origin of cellular life. These RNAs have the ability to form membraneless compartments and carry out chemical reactions, allowing them to adapt rapidly to stress. This process, known as liquid-liquid phase separation (LLPS), creates a comprehensive bioreactor in which the chemicals that are essential for life can be synthesised.
    “We are delighted to discover the important roles of different types of genes in health and personality. It is amazing to see that evolution has preserved genes that are thought to have been important in the origin of life, allowing for the increasing plasticity, complexity and consciousness that we observe in humans. The innovative computational methods used in this project enable us to study complex biological systems in humans in an ethical, non-intrusive and beneficial way, with the aim of understanding how to live healthily,” says Professor Cloninger. He adds: “These findings clearly demonstrate that a person’s mind and body are deeply interconnected. Each influences the other, so they are not separate. It is important to recognise that our future well-being is not entirely determined by our past or present conditions; rather, we can cultivate our own well-being in a creative process full of open-ended possibilities.” More

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    Cellphone compass can measure tiny concentrations of compounds important for human health

    Nearly every modern cellphone has a built-in compass, or magnetometer, that detects the direction of Earth’s magnetic field, providing critical information for navigation. Now a team of researchers at the National Institute of Standards and Technology (NIST) has developed a technique that uses an ordinary cellphone magnetometer for an entirely different purpose — to measure the concentration of glucose, a marker for diabetes, to high accuracy.
    The same technique, which uses the magnetometer in conjunction with magnetic materials designed to change their shape in response to biological or environmental cues, could be used to rapidly and cheaply measure a host of other biomedical properties for monitoring or diagnosing human disease. The method also has the potential to detect environmental toxins, said NIST scientist Gary Zabow.
    In their proof-of-concept study, Zabow and fellow NIST researcher Mark Ferris clamped to a cellphone a tiny well containing the solution to be tested and a strip of hydrogel — a porous material that swells when immersed in water. The researchers embedded tiny magnetic particles within the hydrogel, which they had engineered to react either to the presence of glucose or to pH levels (a measure of acidity) by expanding or contracting. Changing pH levels can be associated with a variety of biological disorders.
    As the hydrogels enlarged or shrunk, they moved the magnetic particles closer to or farther from the cellphone’s magnetometer, which detected the corresponding changes in the strength of the magnetic field. Employing this strategy, the researchers measured glucose concentrations as small as a few millionths of a mole (the scientific unit for a certain number of atoms or molecules in a substance). Although such high sensitivity is not required for at-home monitoring of glucose levels using a drop of blood, it might in the future enable routine testing for glucose in saliva, which contains a much smaller concentration of the sugar.
    The researchers reported their findings in the March 30, 2024 edition of Nature Communications.
    Engineered, or “smart,” hydrogels like the ones the NIST team employed are inexpensive and relatively easy to fabricate, Ferris said, and can be tailored to react to a host of different compounds that medical researchers may want to measure. In their experiments, he and Zabow stacked single layers of two different hydrogels, each of which contracted and expanded at different rates in response to pH or glucose. These bilayers amplified the motion of the hydrogels, making it easier for the magnetometer to track changes in magnetic field strength.
    Because the technique does not require any electronics or power source beyond that of the cellphone nor call for any special processing of the sample, it offers an inexpensive way to conduct testing — even in locations with relatively few resources.

    Future efforts to improve the accuracy of such measurements using cellphone magnetometers might allow detection of DNA strands, specific proteins and histamines — compounds involved in the body’s immune response — at concentrations as low as a few tens of nanomoles (billionths of a mole).
    That improvement could have substantial benefit. For instance, measuring histamines, which are typically detected in urine at concentrations ranging from about 45 to 190 nanomoles, would ordinarily require a 24-hour urine collection and a sophisticated laboratory analysis.
    “An at-home test using a cellphone magnetometer sensitive to nanomolar concentrations would allow measurements to be done with much less hassle,” said Ferris. More generally, enhanced sensitivity would be essential when only a small amount of a substance is available for testing in extremely dilute quantities, Zabow added.
    Similarly, the team’s study suggests that a cellphone magnetometer can measure pH levels with the same sensitivity as a thousand-dollar benchtop meter but at a fraction of the cost. A home-brewer or a baker could use the magnetometer to quickly test the pH of various liquids to perfect their craft, and an environmental scientist could measure the pH of ground water samples on-site with higher accuracy than a litmus test strip could provide.
    In order to make the cellphone measurements a commercial success, engineers will need to develop a method to mass produce the hydrogel test strips and ensure that they have a long shelf life, Zabow said. Ideally, he added, the hydrogel strips should be designed to react more quickly to environmental cues in order to speed up measurements. More

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    Physics-based predictive tool will speed up battery and superconductor research

    From lithium-ion batteries to next-generation superconductors, the functionality of many modern, advanced technologies depends on the physical property known as intercalation. Unfortunately, it’s difficult to identify in advance which of the many possible intercalated materials are stable, which necessitates a lot of trial-and-error lab work in product development.
    Now, in a study recently published in ACS Physical Chemistry Au, researchers from the Institute of Industrial Science, The University of Tokyo, and collaborating partners have devised a straightforward equation that correctly predicts the stability of intercalated materials. The systematic design guidelines enabled by this work will speed up the development of upcoming high-performance electronics and energy-storage devices.
    To appreciate the research team’s achievement, we need to understand the context of this research. Intercalation is the reversible insertion of guests (atoms or molecules) into hosts (for example, 2D-layered materials). The purpose of intercalation is commonly to modify the host’s properties or structure for improved device performance, as seen in, for example, commercial lithium-ion batteries. Although many synthetic methods are available for preparing intercalated materials, researchers have had no reliable means of predicting which host-guest combinations are stable. Therefore, much lab work has been needed to devise new intercalated materials for imparting next-generation device functionalities. Minimizing this lab work by proposing a straightforward predictive tool for host-guest stability was the goal of the research team’s study.
    “We are the first to develop accurate predictive tools for host-guest intercalation energies, and the stability of intercalated compounds,” explains Naoto Kawaguchi, lead author of the study. “Our analysis, based on a database of 9,000 compounds, uses straightforward principles from undergraduate first-year chemistry.”
    A particular highlight of the work is that only two guest properties and eight host-derived descriptors were necessary for the researchers’ energy and stability calculations. In other words, initial ‘best guesses’ weren’t necessary; only the underlying physics of the host-guest systems. Furthermore, the researchers validated their model against nearly 200 sets of regression coefficients.
    “We’re excited because our regression model formulation is straightforward and physically reasonable,” says Teruyasu Mizoguchi, senior author. “Other computational models in the literature lack a physical basis or validation against unknown intercalated compounds.”
    This work is an important step forward in minimizing the laborious lab work that’s typically required to prepare intercalated materials. Given that many current and upcoming energy storage and electronic devices depend on such materials, the time and expense required for corresponding research and development will be minimized. Consequently, products with advanced functionalities will reach the market faster than what has been previously possible. More

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    App may pave way to treatments for no. 1 dementia in under-60s

    UCSF-led research shows smartphone cognitive testing is comparable to gold-standard methods; may detect FTD in gene carriers before symptoms start.
    A smartphone app could enable greater participation in clinical trials for people with frontotemporal dementia (FTD), a devastating neurological disorder that often manifests in midlife.
    Research into the condition has been hampered by problems with early diagnosis and difficulty tracking how people are responding to treatments that are only likely to be effective at the early stages of disease.
    To address this, a research team led by UC San Francisco deployed cognitive tests through a mobile app and found it could detect early signs of FTD in people who were genetically predisposed to get the disease but had not yet developed symptoms. These tests were at least as sensitive as neuropsychological evaluations done in the clinic.
    The study appears in JAMA Network Open on April 1, 2024.
    More than 30 FTD clinical trials are underway or in the planning stages, including one that may become the first drug approved to slow progression in some gene carriers. Researchers hope the new mobile technology will hasten the work.
    “Eventually, the app may be used to monitor treatment effects, replacing many or most in-person visits to clinical trials’ sites,” said first author Adam Staffaroni, PhD, clinical neuropsychologist and associate professor in the UCSF Department of Neurology and the Weill Institute for Neurosciences.

    FTD is the No. 1 cause of dementia in patients under 60, with up to 30% of cases attributed to genetics. It has three main variants with symptoms that may overlap. The most common causes dramatic personality shifts, which may manifest as lack of empathy, apathy, impulsivity, compulsive eating, and socially and sexually inappropriate behavior. Another affects movement, and a third impacts speech, language and comprehension, which is the variant that Bruce Willis is reported to have. In rare cases, FTD triggers bursts of visual creativity.
    FTD is not easy to diagnose
    As with Alzheimer’s disease, patients with FTD are believed to be most responsive to treatment early on, ideally before their symptoms even emerge. “Most FTD patients are diagnosed relatively late in the disease, because they are young, and their symptoms are mistaken for psychiatric disorders,” said senior author Adam Boxer, MD, PhD, endowed professor in memory and aging at the UCSF Department of Neurology.
    “We’ve heard from families that they often suspect their loved one has FTD long before a physician agrees that is the diagnosis,” said Boxer, who is also director of the UCSF Alzheimer’s Disease and Frontotemporal Dementia Clinical Trials Program.
    The researchers tracked 360 participants with an average age of 54 enrolled in ongoing studies at ALLFTDcenters and UCSF. About 90% had data on disease stage. These included 60% who did not have FTD or were gene carriers who had not yet developed symptoms, 20% with early signs of the disease and 21% with symptoms.
    Software that can detect a waning ability to plan
    Staffaroni and Boxer collaborated with software company Datacubed Health, which developed the platform, to include tests of executive function, such as planning and prioritizing, filtering distractions and controlling impulses. In FTD, the part of the brain responsible for executive functioning shrinks as the disease progresses.

    The rich data collected by the app, including voice recordings and body movements, enabled the researchers to develop new tests that eventually could help with early diagnosis and monitoring of symptoms.
    “We developed the capability to record speech while participants engaged with several different tests,” said Staffaroni. “We also created tests of walking, balance and slowed movements, as well as different aspects of language.”
    FTD researchers say they are closer to finding treatments that may eventually slow the progression of the disease, which is fatal. These include gene and other therapies, such as antisense oligonucleotides (ASOs), to increase or decrease the production of proteins that are abnormal in gene carriers.
    Although there are currently no plans to make the app available to the public, it could be a boon to research.
    “A major barrier has been a lack of outcome measures that can be easily collected and are sensitive to treatment effects at early stages of the disease,” said Staffaroni. “We hope that smartphone assessments will facilitate new trials of promising therapies.” More

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    Chatbot outperformed physicians in clinical reasoning in head-to-head study

    ChatGPT-4, an artificial intelligence program designed to understand and generate human-like text, outperformed internal medicine residents and attending physicians at two academic medical centers at processing medical data and demonstrating clinical reasoning. In a research letter published in JAMA Internal Medicine, physician-scientists at Beth Israel Deaconess Medical Center (BIDMC) compared a large language model’s (LLM) reasoning abilities directly against human performance using standards developed to assess physicians.
    “It became clear very early on that LLMs can make diagnoses, but anybody who practices medicine knows there’s a lot more to medicine than that,” said Adam Rodman MD, an internal medicine physician and investigator in the department of medicine at BIDMC. “There are multiple steps behind a diagnosis, so we wanted to evaluate whether LLMs are as good as physicians at doing that kind of clinical reasoning. It’s a surprising finding that these things are capable of showing the equivalent or better reasoning than people throughout the evolution of clinical case.”
    Rodman and colleagues used a previously validated tool developed to assess physicians’ clinical reasoning called the revised-IDEA (r-IDEA) score. The investigators recruited 21 attending physicians and 18 residents who each worked through one of 20 selected clinical cases comprised of four sequential stages of diagnostic reasoning. The authors instructed physicians to write out and justify their differential diagnoses at each stage. The chatbot GPT-4 was given a prompt with identical instructions and ran all 20 clinical cases. Their answers were then scored for clinical reasoning (r-IDEA score) and several other measures of reasoning.
    “The first stage is the triage data, when the patient tells you what’s bothering them and you obtain vital signs,” said lead author Stephanie Cabral, MD, a third-year internal medicine resident at BIDMC. “The second stage is the system review, when you obtain additional information from the patient. The third stage is the physical exam, and the fourth is diagnostic testing and imaging.”
    Rodman, Cabral and their colleagues found that the chatbot earned the highest r-IDEA scores, with a median score of 10 out of 10 for the LLM, 9 for attending physicians and 8 for residents. It was more of a draw between the humans and the bot when it came to diagnostic accuracy — how high up the correct diagnosis was on the list of diagnosis they provided — and correct clinical reasoning. But the bots were also “just plain wrong” — had more instances of incorrect reasoning in their answers — significantly more often than residents, the researchers found. The finding underscores the notion that AI will likely be most useful as a tool to augment, not replace, the human reasoning process.
    “Further studies are needed to determine how LLMs can best be integrated into clinical practice, but even now, they could be useful as a checkpoint, helping us make sure we don’t miss something,” Cabral said. “My ultimate hope is that AI will improve the patient-physician interaction by reducing some of the inefficiencies we currently have and allow us to focus more on the conversation we’re having with our patients.
    “Early studies suggested AI could makes diagnoses, if all the information was handed to it,” Rodman said. “What our study shows is that AI demonstrates real reasoning — maybe better reasoning than people through multiple steps of the process. We have a unique chance to improve the quality and experience of healthcare for patients.”
    Co-authors included Zahir Kanjee, MD, Philip Wilson, MD, and Byron Crowe, MD, of BIDMC; Daniel Restrepo, MD, of Massachusetts General Hospital; and Raja-Elie Abdulnour, MD, of Brigham and Women’s Hospital.
    This work was conducted with support from Harvard Catalyst | The Harvard Clinical and Translational Science Center (National Center for Advancing Translational Sciences, National Institutes of Health) (award UM1TR004408) and financial contributions from Harvard University and its affiliated academic healthcare centers.
    Potential Conflicts of Interest: Rodman reports grant funding from the Gordon and Betty Moore Foundation. Crowe reports employment and equity in Solera Health. Kanjee reports receipt of royalties for books edited and membership on a paid advisory board for medical education products not related to AI from Wolters Kluwer, as well as honoraria for continuing medical education delivered from Oakstone Publishing. Abdulnour reports employment by the Massachusetts Medical Society (MMS), a not-for-profit organization that owns NEJM Healer. Abdulnour does not receive royalty from sales of NEJM Healer and does not have equity in NEJM Healer. No funding was provided by the MMS for this study. Abdulnour reports grant funding from the Gordan and Betty Moore Foundation via the National Academy of Medicine Scholars in Diagnostic Excellence. More

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    Research reveals language barriers limit effectiveness of cybersecurity resources

    The idea for Fawn Ngo’s latest research came from a television interview.
    Ngo, a University of South Florida criminologist, had spoken with a Vietnamese language network in California about her interest in better understanding how people become victims of cybercrime.
    Afterward, she began receiving phone calls from viewers recounting their own experiences of victimization.
    “Some of the stories were unfortunate and heartbreaking,” said Ngo, an associate professor in the USF College of Behavioral and Community Sciences. “They made me wonder about the availability and accessibility of cybersecurity information and resources for non-English speakers. Upon investigating further, I discovered that such information and resources were either limited or nonexistent.”
    The result is what’s believed to be the first study to explore the links among demographic characteristics, cyber hygiene practices and cyber victimization using a sample of limited English proficiency internet users.
    Ngo is the lead author of an article, “Cyber Hygiene and Cyber Victimization Among Limited English Proficiency (LEP) Internet Users: A Mixed-Method Study,” which just published in the journal Victims & Offenders. The article’s co-authors are Katherine Holman, a USF graduate student and former Georgia state prosecutor, and Anurag Agarwal, professor of information systems, analytics and supply chain at Florida Gulf Coast University.
    Their research, which focused on Spanish and Vietnamese speakers, led to two closely connected main takeaways: LEP Internet users share the same concern about cyber threats and the same desire for online safety as any other individual. However, they are constrained by a lack of culturally and linguistically appropriate resources, which also hampers accurate collection of cyber victimization data among vulnerable populations. Online guidance that provides the most effective educational tools and reporting forms is only available in English. The most notable example is the website for the Internet Crime Complaint Center, which serves as the FBI’s primary apparatus for combatting cybercrime.As a result, the study showed that many well-intentioned LEP users still engage in risky online behaviors like using unsecured networks and sharing passwords. For example, only 29 percent of the study’s focus group participants avoided using public Wi-Fi over the previous 12 months, and only 17 percent said they had antivirus software installed on their digital devices.

    Previous research cited in Ngo’s paper has shown that underserved populations exhibit poorer cybersecurity knowledge and outcomes, most commonly in the form of computer viruses and hacked accounts, including social media accounts. Often, it’s because they lack awareness and understanding and isn’t a result of disinterest, Ngo said.
    “According to cybersecurity experts, humans are the weakest link in the chain of cybersecurity,” Ngo said. “If we want to secure our digital borders, we must ensure that every member in society, regardless of their language skills, is well-informed about the risks inherent in the cyber world.”
    The study’s findings point to a need for providing cyber hygiene information and resources in multiple formats, including visual aids and audio guides, to accommodate diverse literacy levels within LEP communities, Ngo said. She added that further research is needed to address the current security gap and ensure equitable access to cybersecurity resources for all Internet users.
    In the meantime, Ngo is preparing to launch a website with cybersecurity information and resources in different languages and a link to report victimization.
    “It’s my hope that cybersecurity information and resources will become as readily accessible in other languages as other vital information, such as information related to health and safety,” Ngo said. “I also want LEP victims to be included in national data and statistics on cybercrime and their experiences accurately represented and addressed in cybersecurity initiatives.” More