Tech

Physics and Chemistry scholars from Hong Kong Baptist University (HKBU) have invented a new method which could speed up the drug discovery process and lead to the production of higher quality medicinal drugs which are purer and have no side effects. The technique, which is a world-first breakthrough, uses a specific nanomaterial layer to detect the target molecules in pharmaceuticals and pesticides in just five minutes.

The new HKBU invention can be applied to the drug discovery process, as well as the production and quality control stages of pharmaceutical manufacturing. It can also be used in environmental monitoring. The paper, which is entitled "Chiral Nanoparticle-Induced Enantioselective Amplification of Molecular Optical Activity", was published in the renowned international journal Advanced Functional Materials (volume 29, issue 8, February 2019).

The team was jointly led by Associate Professor Dr Jeffery Huang Zhifeng and Postdoctoral Fellow Dr Lin Yang from the Department of Physics, and Associate Professor Dr Ken Leung Cham-fai and Postdoctoral Fellow Dr Kwan Chak-shing from the Department of Chemistry at HKBU.

Medicinal drugs and pesticides are composed of organic molecules. Normally each molecule has two "chiral" versions which are mirror images of each other in terms of absolute configuration. While otherwise identical, these "right-handed" and "left-handed" molecules can have totally different effects. For example, anti-inflammatory drug naproxen of a particular type of chirality can treat arthritis pain while its mirror image twin can result in liver poisoning. As a result, selecting only useful chiral molecules during the drug discovery process can help produce pure drugs that can cure specific diseases with no adverse effects.

However, producing pure drugs is very expensive and time consuming. Current medicinal drugs are often made up of equal amounts of the left- and right-handed chiral molecules in what is known as a racemic mixture. While this fifty-fifty split has low production cost, it also leads to lower overall efficacy and, in some cases, can lead to toxic side effects in the human body.

According to Dr Jeffery Huang, sensitively identifying and locating the correct form of a chiral molecule during the drug discovery process is essential, but is currently difficult and time-consuming because molecules are typically too small to be sensitively monitored. However, the specific nanomaterial designed and synthesised by the team, which is composed of silver chiral nanoparticles, can "amplify" the signal of the desired chiral molecules and improve detection sensitivity by more than 10-fold, making the location process faster, more accurate and less expensive.

Dr Huang said that this work opens a new door for material scientists to apply these metallic chiral nanoparticles to drug production processes, as currently there are a limited number of nanomaterial fabrication techniques on offer. He said: "We have developed a breakthrough nanomaterial which uses a simple, one-step fabrication method to sensitively detect the target drug molecules in just five minutes. The ability of the chiral nanoparticles to amplify the detection sensitivity is practically desired for trace detection."

Dr Ken Leung said that in the current multi-step drug synthesis process, both the product and chiroptical purities - which refers to the use of optical techniques for investigating chiral substances - are crucial controlling factors for producing extra-pure synthetic drug molecules. The novel nanomaterial developed by the team will eventually provide a new platform for efficiently and effectively detecting the chiroptical purity of synthesised compounds, and will help to produce drugs without side effects. It is also a new breakthrough in the resolution of racemic drugs, he added.

Milan, Italy: A single high dose of radiation that can be delivered directly to the tumour within a few minutes is a safe and effective technique for treating men with low risk prostate cancer, according to a study presented at the ESTRO 38 conference.

Radiotherapy traditionally involves a series of lower dose treatments that take place over several days or week. The new treatment is called high dose-rate brachytherapy and it delivers radiation via a set of tiny tubes.

Researchers say this technique could offer an effective treatment that is convenient for patients and brings potential time and cost savings for hospitals.

The research was presented by Dr Hannah Tharmalingam, a Clinical Research Fellow at Mount Vernon Cancer Centre, Northwood, and The Christie NHS Foundation Trust, Manchester, UK.

She said: "Brachytherapy, where we use temporary catheters to directly treat tumours, has already proved to be a good treatment for prostate cancer, both in terms of killing the cancer cells and minimising side effects. This usually means patients make four to six visits to the hospital for a series of lower dose treatments. We wanted to see whether we could get similar results but with just one high dose treatment, saving time for the patient and the hospital."

The research included 441 men with prostate cancer who were treated at one of seven UK hospitals [1] between 2013 and 2018. Their cancers were classified, depending on how likely they were to spread, as either low risk (total of 44 men), medium risk (285 men) or high risk (112 men). All were treated with a single high dose (19 Gy) of radiation; 166 men also received hormone therapy but none had any surgery or chemotherapy.

Researchers monitored the men's progress for an average of 26 months. They measured the levels of prostate specific antigen (PSA) in the men's blood two years after the treatment and again three years after the treatment. PSA is considered to be a good indicator of how well prostate cancer treatment has worked. If levels increase, this can indicate the cancer has returned.

Overall, after two years, 94% of men showed no sign of the cancer returning, according to their PSA levels. For men with low risk cancer this figure was 100%, in men with medium risk it was 95% and in men with high risk cancer it was 92%. After three years, the overall figure was 88%, and in men with low, medium and high risk cancers, the figures were 100%, 86% and 75% respectively.

Of the 27 men with raised PSA levels, researchers were able to identify where the cancer had returned in 25. In 15, the cancer had returned in the prostate. In the rest, it had spread to other parts of the body.

At the time of the treatment, there were no serious side effects. Later on, two men developed urethral strictures that required surgery and two developed rectal fistulae that required colostomy.

Dr Tharmalingam said: "These results indicate that high dose-rate brachytherapy is a safe and effective treatment for men with low risk prostate cancer but further research is needed in medium and high risk patients to see if the results can be improved with a higher dose. This type of treatment offers an attractive alternative to surgery or other forms of radiotherapy as it has a comparatively low risk of side effects. It is also a patient-friendly option because the treatment can be given quickly at a single hospital visit."

Dr Tharmalingam and her colleagues hope to continue studying the impact of using this type of radiotherapy, especially in patients with higher risk prostate cancer who are more likely to suffer a recurrence. She believes it would be possible, given the low risk of side effects, to modify the treatment or increase the dose even further in higher risk cases.

Dr Bradley Pieters, chair of ESTRO's brachytherapy committee and a radiation oncologist at the Academic University Medical Centers, The Netherlands, who was not involved in the study, said: "This research suggests that a single treatment of high dose-rate brachytherapy could be a very good option for many men with prostate cancer. The technology and expertise needed to deliver this treatment is not yet available in all cancer centres. However, given that it may offer time and money savings for hospitals as well as benefits to patients, there is a good argument for investing in this type of radiotherapy."

BALTIMORE - An estimated 5 percent of all children under the age of five were missed in the 2010 U.S. Census. A plenary during the Pediatric Academic Societies (PAS) 2019 Meeting in Baltimore will address the impact this significant undercount had, how the Census relates to health care resources and the role pediatricians, clinics, hospitals and communities can play to help make sure all children are counted in the 2020 Census.

"Young children under the age of five are among the groups who are most likely to be undercounted by the Census which can greatly impact the resources that are available to educate, feed, house and care for them," said Judy Aschner, MD, Chairperson of the Federation of Pediatric Organizations (FOPO); Professor and the Marvin I. Gottlieb, M.D., Ph.D. Chair, Department of Pediatrics Hackensack Meridian Health; Physician-in-Chief, Joseph M. Sanzari Children's Hospital.

Dr. Aschner continued, "This plenary is not only to educate the pediatric community about the impact that the Census has on our children, but a launch pad for actionable steps and initiatives pediatricians can take to inform our communities."

The Decennial Census not only determines how over $675 billion in federal funds are allocated, but it is used to draw district lines and to give voice to those who live in the U.S. If individuals are not counted, they, their families and their communities have a lot to lose. The plenary will educate the audience on the importance of the Census and why it is critical to count everyone, in particular, young children. It will set the stage for an in-depth discussion on the topic and action items for the pediatric health care community.

There are numerous programs that determine specifically where the $675 billion of funding is distributed, including Medicaid and the Children's Health Insurance Program (CHIP), Supplemental Nutrition Assistance Program (SNAP), the foster care system, school lunch programs and Title I funding to schools in low income communities and IDEA special education funding for children with disabilities.

Additionally, the data and findings derived from the decennial Census has more than just monetary implications. The Census data is used by businesses, governments and civic organizations to inform decision-making as well as by investigators for epidemiologic, health services, environmental, and population-based research.

Dr. Aschner concluded, "As trusted voices in the communities we serve, the Census Bureau needs the help of all pediatricians to help educate parents on the importance of completing the census survey and including all family members, including young children."

The plenary will be introduced and moderated by Dr. Aschner. The session will feature presentations by Dr. Ron Jarmin of the U.S. Census Bureau, Lisa Hamilton of the Annie E. Casey Foundation and Arturo Vargas of the NALEO Educational Fund.

Session affiliations include: American Academy of Pediatrics (AAP), AAP Section of Neonatal Perinatal Pediatrics, American Pediatric Society (APS), APS Day, Federation of Pediatric Organizations and Society for Pediatric Research.

The plenary entitled "The 2020 Census: Why It Is Important for Children's Health, and the Challenge of the Young Child Undercount" will be held on Sunday, April 28 at 8 a.m. EDT in the Baltimore Convention Center Ballroom II. Reporters interested in an interview with Dr. Aschner should contact PAS2019@piercom.com.

The PAS 2019 Meeting brings together thousands of pediatricians and other health care providers to improve the health and well-being of children worldwide. For more information about the PAS 2019 Meeting, please visit http://www.pas-meeting.org.

Like memories in computers, quantum memories are essential components for quantum computers - a new generation of data processors that obey quantum mechanics laws and can overcome the limitations of classical computers. They may push boundaries of fundamental science and help create new drugs, explain cosmological mysteries, or enhance accuracy of forecasts and optimization plans with their potent computational power. Quantum computers are expected to be much faster and more powerful than their traditional counterparts as information is calculated in qubits - which unlike the older units (bits) used in classical computers, can represent both 0 and 1 at the same time.

Photonic quantum memories allow for the storage and retrieval of flying single-photon quantum states. However, production of such highly-efficient quantum memories remains a major challenge as it requires perfectly matched photon-matter quantum interface. Meanwhile, the energy of a single photon is too weak and can be easily lost into the noisy sea of stray light background. For a long time, these problems suppressed quantum memory efficiencies to below 50% - a threshold value crucial for practical applications.

Now for the first time in history, a joint research team led by Prof. DU Shengwang from the Department of Physics and William Mong Institute of Nano Science and Technology at HKUST; Prof. ZHANG Shanchao from SCNU who graduated his PhD study at HKUST; Prof. YAN Hui from SCNU and a former postdoctoral fellow at HKUST; as well as Prof. ZHU Shi-Liang from SCNU and Nanjing University, has found a way to boost the efficiency of photonic quantum memories to over 85% with a fidelity of over 99%.

The team created such a quantum memory by trapping billions of rubidium atoms into a hair-like tiny space - those atoms are cooled down to nearly absolute zero temperature (about 0.00001 K) using lasers and magnetic field. The team also found a smart way to distinguish the single photon from the noisy background light sea. The finding brought the dream of an 'universal' quantum computer a step closer to reality. Such quantum memories can also be used as repeaters in a quantum network, laying the foundation for a new generation of quantum-based internet.

"In this work, we code a flying qubit onto the polarization of a single photon and store it into the laser-cooled atoms," said Prof Du. "Although the quantum memory demonstrated in this work is only for one qubit operation, it opens the possibility for emerging quantum technology and engineering in the future."

The finding was recently published as a cover story of the authoritative journal Nature Photonics - the latest of a series of research from Prof Du's lab on quantum memory, first begun in 2011.

BALTIMORE - A new study aims to determine the underlying etiology of seizures and help to target therapy, improve control of seizures, and potentially reduce morbidities in children. Findings from the study will be presented during the Pediatric Academic Societies (PAS) 2019 Meeting, taking place on April 24 - May 1 in Baltimore.

"As a neonatologist working with the team at the Genomics Institute, I've seen first-hand that rapid whole genome sequencing (rWGS) can be effective in identifying etiology of unexplained seizures in neonates and subsequently optimizing their care," said Jeanne Carroll, MD, one of the authors of the study. "Early rWGS can give answers to distressed families, help physicians provide a prognosis, and most importantly may help guide therapy with the potential to impact outcomes. A retrospective analysis of 19 patients who were admitted to the neonatal intensive care unit (NICU), with unclear etiology of seizures received WGS resulting in a molecular diagnosis for six infants. Of those six patients, four received a change in medical management as a result of the genetic diagnosis."

This study retrospectively identified a cohort of patients admitted in the first 30 days of life with presenting symptom of seizures who also underwent rapid whole genome sequencing during the admission. These cases were reviewed to assess for etiology of seizure, results of rWGS, and changes in management based on rWGS results.

Nineteen patients were identified with average age at admission of four days and average hospital day at which sequencing was sent of 3.3. There were six diagnoses made by rWGS (31.6%). Four patients were later found on neuroimaging to have a stroke and three had changes of hypoxic ischemic encephalopathy (HIE) on MRI. Four of the six diagnoses led to a change in management including three with targeted seizure medications, and one with a referral to neurometabolic specialist and addition of dietary supplements. Two patients were found to have KCNQ2 mutations, both had significant side effects from antiepileptic medications. In each case, the medication regimen was optimized based on genetic findings leading to control of seizures and reduction in side effects from non-targeted therapies. In this cohort there was also a pyridoxine dependent epilepsy, two syndromic causes of seizures and one metabolic condition identified.

The study concluded that rWGS can identify etiology and direct therapy in the neonate with unexplained seizures.

Dr. Carroll will present findings from "Clinical Utility of rWGS in the Evaluation of Neonatal Seizures" on Saturday, April 27 at 9:15 a.m. EDT. Reporters interested in an interview with Dr. Carroll should contact PAS2019@piercom.com. Please note that only the abstracts are being presented at the meeting. In some cases, the researchers may have additional data to share with media.

The PAS 2019 Meeting brings together thousands of pediatricians and other health care providers to improve the health and well-being of children worldwide. For more information about the PAS 2019 Meeting, please visit http://www.pas-meeting.org.

BALTIMORE - A new study found that personal gun access was associated with depression, suicidal ideation and perceiving school as unsafe, while attending a school where gun access was common was associated with lower odds of perceiving school as unsafe. Findings from the study will be presented during the Pediatric Academic Societies (PAS) 2019 Meeting, taking place on April 24 - May 1 in Baltimore.

Recent high-profile shootings have raised awareness of the health effects of both access and exposure to firearms and firearm violence among youth and adolescents. Access to guns and perceived unsafe school environments have been associated with gun-related injury, depression and suicidality among adolescents. Whether widespread acceptance of guns among peers alters these associations, however, is unknown.

When interaction terms were included in the models, the association between individual gun access and suicidal ideation was weaker when attending a school where gun access was more common. Additionally, as access to guns within a school was more common, the odds of poor general health decreased for students with personal gun access but increased for students with no personal gun access.

"For better or for worse, guns are an important part of American culture," said Samantha Chung, one of the authors of the study. "Some studies have shown that having a gun in the home is associated with poor mental health among adolescents. We wanted to study how overall gun access in adolescents' communities might also impact their mental health. We found that it probably does, but the effects are complex and may go in both directions."

The study concluded that gun access is a complex social phenomenon. In an otherwise low-access environment, personal gun access may signify a high-risk physical and mental state. In schools where access to guns is common, however, personal gun access may signify social belonging that might reduce potential negative health effects of guns. Although overall evidence that widespread gun access is harmful remains clear, our findings suggest that nuance based on local cultural norms may be significant.

Chung will present findings from "Gun Access and Adolescent Health: Safety in Numbers?" on Monday, April 29 at 2:15 p.m. EDT. Reporters interested in an interview with Chung should contact PAS2019@piercom.com. Please note that only the abstracts are being presented at the meeting. In some cases, the researchers may have additional data to share with media.

The PAS 2019 Meeting brings together thousands of pediatricians and other health care providers to improve the health and well-being of children worldwide. For more information about the PAS 2019 Meeting, please visit http://www.pas-meeting.org.

Women who have undergone weight-loss surgery appear to be at higher risk of developing complications during pregnancy, and their babies seem more likely to be born prematurely, small for gestational age, have congenital anomalies and be admitted to intensive care, according to the most comprehensive assessment of how bariatric surgery affects pregnancy outcomes, being presented at this year's European Congress on Obesity (ECO) in Glasgow, UK (28 April-1 May).

The systematic review and meta-analysis, synthesising all the available evidence from the scientific literature, compared over 14,800 pregnancies in women who had previously undergone weight-loss surgery with almost 4 million pregnancies in mothers who had not.

The authors say that pregnant women with a history of weight-loss surgery should be considered as high-risk, be provided additional support throughout pregnancy, and mother and baby should be monitored closely.

"Our findings indicate that women with a history of bariatric surgery, and in particular gastric bypass surgery, are at much greater risk of several adverse perinatal outcomes", says Zainab Akhter, a PhD student from Newcastle University, UK who led the research. "These women require specific preconception and pregnancy nutritional support. This highlights the importance of dietary supplements, and extra monitoring of fetal growth and development. Health professionals also need training and guidance to be able to provide the right advice."

Pregnant women with obesity are at higher risk of developing complications such as gestational diabetes and hypertension. Weight-loss surgery before pregnancy improves these outcomes, but some bariatric procedures, such as gastric bypass, affect the absorption of micronutrients and may impair fetal development. In the UK, 3 out of every 4 bariatric surgery patients are women, and the majority of them are of childbearing age.

In this study, the researchers conducted a systematic review and meta-analysis of observational studies comparing adverse perinatal outcomes after bariatric surgery to pregnancies without prior weight-loss surgery up to December 2018. Data from 33 articles were analysed, comparing 14,880 pregnancies after bariatric surgery with almost 4 million pregnancies in women who had not undergone surgery.

The meta-analyses were dependent on the quality of the included studies, sample sizes, and whether they adjusted for factors which can affect perinatal outcomes such as age, smoking status, and diabetes.

Results showed that babies born after weight-loss surgery were 57% more likely to be born premature, 29% more likely to have congenital anomalies, and 41% more likely to be admitted to a neonatal intensive care unit compared to the control group. Moreover, babies born after obesity surgery were also at a 38% greater risk of perinatal death, defined as being stillborn or dying within 7 days of birth.

Additionally, babies born after bariatric surgery were on average over 200g lighter than those born to mothers without a history of weight-loss surgery. However, the pregnancies of women with a history of weight-loss surgery were of shorter duration.

Further analyses showed that women who had a gastric bypass were 2.7 times more likely to have babies that were small for gestational age, and but had a quarter of the risk (or a 76% reduced risk) of giving birth to large for gestational age babies.

"It is not clear how weight-loss surgery may influence fetal development, but we know that people who have bariatric surgery are more likely to have micronutrient deficiencies", says Zainab. "More work needs to be done to better understand the causes of these differences, so that steps can be taken to support women to achieve the best possible pregnancy outcomes for themselves and their babies."

The authors acknowledge that their findings show observational differences, so no firm conclusions can be drawn about cause and effect, and they point to several limitations, including that unmeasured confounding (ie, differences in unmeasured factors which may have affected the health outcomes of the study) may have influenced the results.

New analysis by academics from the Oxford Internet Institute (OII), part of the University of Oxford, predicts the dead may outnumber the living on Facebook within fifty years, a trend that will have grave implications for how we treat our digital heritage in the future.

The analysis predicts that, based on 2018 user levels, at least 1.4 billion members will die before 2100. In this scenario, the dead could outnumber the living by 2070. If the world's largest social network continues to expand at current rates, however, the number of deceased users could reach as high as 4.9 billion before the end of the century.

"These statistics give rise to new and difficult questions around who has the right to all this data, how should it be managed in the best interests of the families and friends of the deceased and its use by future historians to understand the past," said lead author Carl Öhman, a doctoral candidate at the OII.

"On a societal level, we have just begun asking these questions and we have a long way to go. The management of our digital remains will eventually affect everyone who uses social media, since all of us will one day pass away and leave our data behind. But the totality of the deceased user profiles also amounts to something larger than the sum of its parts. It is, or will at least become, part of our global digital heritage."

Co-author David Watson, also a DPhil student at the OII, explained: "Never before in history has such a vast archive of human behaviour and culture been assembled in one place. Controlling this archive will, in a sense, be to control our history. It is therefore important that we ensure that access to these historical data is not limited to a single for-profit firm. It is also important to make sure that future generations can use our digital heritage to understand their history."

The analysis sets up two potential extreme scenarios, arguing that the future trend will fall somewhere in between:

The first scenario assumes that no new users join as of 2018. Under these conditions, Asia's share of dead users increases rapidly to account for nearly 44% of the total by the end of the century. Nearly half of those profiles come from India and Indonesia, which together account for just under 279 million Facebook mortalities by 2100.

The second scenario assumes that Facebook continues to grow by its current rate of 13% globally, every year, until each market reaches saturation. Under these conditions, Africa will make up a growing share of dead users. Nigeria, in particular, becomes a major hub in this scenario, accounting for over 6% of the total. By contrast, Western users will account for only a minority of users, with only the US making the top 10.

"The results should be interpreted not as a prediction of the future, but as a commentary on the current development, and an opportunity to shape what future we are headed towards," explains Öhman. "But this has no bearing on our larger point that critical discussion of online death and its macroscopic implications is urgently needed. Facebook is merely an example of what awaits any platform with similar connectivity and global reach."

Watson added: "Facebook should invite historians, archivists, archaeologists and ethicists to participate in the process of curating the vast volume of accumulated data that we leave behind as we pass away. This is not just about finding solutions that will be sustainable for the next couple of years, but possibly for many decades ahead."

The predictions are based on data from the United Nations, which provide the expected number of mortalities and total populations for every country in the world distributed by age, and Facebook data scraped from the company's Audience Insights feature. While the study notes that this self-reported dataset has several limitations, this provides the most comprehensive publicly available estimate of the network's size and distribution

CAMBRIDGE, MA -- MIT engineers have designed tiny robots that can help drug-delivery nanoparticles push their way out of the bloodstream and into a tumor or another disease site. Like crafts in "Fantastic Voyage" -- a 1960s science fiction film in which a submarine crew shrinks in size and roams a body to repair damaged cells -- the robots swim through the bloodstream, creating a current that drags nanoparticles along with them.

The magnetic microrobots, inspired by bacterial propulsion, could help to overcome one of the biggest obstacles to delivering drugs with nanoparticles: getting the particles to exit blood vessels and accumulate in the right place.

"When you put nanomaterials in the bloodstream and target them to diseased tissue, the biggest barrier to that kind of payload getting into the tissue is the lining of the blood vessel," says Sangeeta Bhatia, the John and Dorothy Wilson Professor of Health Sciences and Technology and Electrical Engineering and Computer Science, a member of MIT's Koch Institute for Integrative Cancer Research and its Institute for Medical Engineering and Science, and the senior author of the study.

"Our idea was to see if you can use magnetism to create fluid forces that push nanoparticles into the tissue," adds Simone Schuerle, a former MIT postdoc and lead author of the paper, which appears in the April 26 issue of Science Advances.

In the same study, the researchers also showed that they could achieve a similar effect using swarms of living bacteria that are naturally magnetic. Each of these approaches could be suited for different types of drug delivery, the researchers say.

Tiny robots

Schuerle, who is now an assistant professor at the Swiss Federal Institute of Technology (ETH Zurich), first began working on tiny magnetic robots as a graduate student in Brad Nelson's Multiscale Robotics Lab at ETH Zurich. When she came to Bhatia's lab as a postdoc in 2014, she began investigating whether this kind of bot could help to make nanoparticle drug delivery more efficient.

In most cases, researchers target their nanoparticles to disease sites that are surrounded by "leaky" blood vessels, such as tumors. This makes it easier for the particles to get into the tissue, but the delivery process is still not as effective as it needs to be.

The MIT team decided to explore whether the forces generated by magnetic robots might offer a better way to push the particles out of the bloodstream and into the target site.

The robots that Schuerle used in this study are 35 hundredths of a millimeter long, similar in size to a single cell, and can be controlled by applying an external magnetic field. This bioinspired robot, which the researchers call an "artificial bacterial flagellum," consists of a tiny helix that resembles the flagella that many bacteria use to propel themselves. These robots are 3-D-printed with a high-resolution 3-D printer and then coated with nickel, which makes them magnetic.

To test a single robot's ability to control nearby nanoparticles, the researchers created a microfluidic system that mimics the blood vessels that surround tumors. The channel in their system, between 50 and 200 microns wide, is lined with a gel that has holes to simulate the broken blood vessels seen near tumors.

Using external magnets, the researchers applied magnetic fields to the robot, which makes the helix rotate and swim through the channel. Because fluid flows through the channel in the opposite direction, the robot remains stationary and creates a convection current, which pushes 200-nanometer polystyrene particles into the model tissue. These particles penetrated twice as far into the tissue as nanoparticles delivered without the aid of the magnetic robot.

This type of system could potentially be incorporated into stents, which are stationary and would be easy to target with an externally applied magnetic field. Such an approach could be useful for delivering drugs to help reduce inflammation at the site of the stent, Bhatia says.

Bacterial swarms

The researchers also developed a variant of this approach that relies on swarms of naturally magnetotactic bacteria instead of microrobots. Bhatia has previously developed bacteria that can be used to deliver cancer-fighting drugs and to diagnose cancer, exploiting bacteria's natural tendency to accumulate at disease sites.

For this study, the researchers used a type of bacteria called Magnetospirillum magneticum, which naturally produces chains of iron oxide. These magnetic particles, known as magnetosomes, help bacteria orient themselves and find their preferred environments.

The researchers discovered that when they put these bacteria into the microfluidic system and applied rotating magnetic fields in certain orientations, the bacteria began to rotate in synchrony and move in the same direction, pulling along any nanoparticles that were nearby. In this case, the researchers found that nanoparticles were pushed into the model tissue three times faster than when the nanoparticles were delivered without any magnetic assistance.

This bacterial approach could be better suited for drug delivery in situations such as a tumor, where the swarm, controlled externally without the need for visual feedback, could generate fluidic forces in vessels throughout the tumor.

The particles that the researchers used in this study are big enough to carry large payloads, including the components required for the CRISPR genome-editing system, Bhatia says. She now plans to collaborate with Schuerle to further develop both of these magnetic approaches for testing in animal models.

It's no surprise that images used for advertising on television and online play a powerful role in triggering emotions and shaping impressions of products or brands, but an ad that appeals to one person may seem irrelevant or distasteful to another. What if it was possible to start personalizing ads viewed by different consumers based on their personality types?

The digital footprints people leave on Facebook, Twitter, text blogs and other online sites provide data to determine whether users are more extroverted or introverted by nature, or eager to try new things versus more conservative. In a new study published in the Journal of Consumer Psychology, researchers show how this digital data could be leveraged with machine learning algorithms to personalize ads based on personality types.

"The goal is to tailor an experience to make it more relevant to a consumer," says study author Sandra Matz, PhD, an assistant professor of management and organizational behavior at Columbia Business School in New York. "It's a way of providing better service to a consumer because the experience is customized."

The researchers started by using computer algorithms to extract 89 features for images, including hue, saturation, color diversity, number of people and level of detail. They recruited 745 participants and asked them to rate how much they liked the images on a scale of one to seven. Then the participants completed a personality test that evaluated them in five areas: openness, conscientiousness, extroversion, agreeableness and neuroticism. The investigators used this data to determine which images appealed to each of these five personality traits.

They discovered, for example, that extroverted people preferred simple images and images that featured people, while open-minded people favored pictures with no people and with cool colors like blue and black. Perhaps not surprisingly, people high in neuroticism liked calm and minimally stimulating scenes. Then the researchers used this information to assign personality types for each image.

In the next study, the researchers explored whether the personality traits assigned to different images accurately predicted consumer preferences. Participants saw images related to products in one of three categories: holiday, beauty or phone. Then they rated the level of appeal for different images. As expected, matching the "personality" of an image to a participant's self-reported personality significantly predicted preference ratings.

The investigators were ultimately interested in learning whether this fit between image and personality could influence a consumer's interest in purchasing a product, and the data showed that this was the case. People not only preferred images that matched their personalities, but also reported more favorable attitudes and purchase intentions towards these brands.

Although brands often target a certain gender, age group or social group with advertisements, personality-matching ads could potentially allow marketers to tailor their products to a wider group of people. A consumer who might not consider shopping online at one store may discover that there are in fact items that would be appealing.

"It's essentially bringing the benefits of talking to a salesperson to the online world," says Matz. "Online marketers typically focus on a large audience, but now we could predict someone's psychological traits to give them an individualized experience."

WASHINGTON, D.C., April 26, 2019 -- An international group of researchers has taken one of the first major steps in finding the biological changes in the brain that drive fetal alcohol spectrum disorder (FASDs). New work using chaos theory to analyze brain signals, discussed this month in the journal Chaos, from AIP Publishing, shows the long-term effects.

Researchers found that teenagers who were exposed to alcohol while in the womb showed altered brain connections that were consistent with impaired cognitive performance. Their findings were reached by measuring the responses from a brain imaging technique called magnetoencephalography (MEG) and then analyzing them with tools developed using chaos theory.

FASDs are one of the leading causes of intellectual disability worldwide and is linked to a wide array of neurological issues, including ADHD. While the prevailing theory links expectant mothers' alcohol consumption to cognitive impairments for children, questions about the extent of this effect remain. Despite the known link, researchers are uncertain about the precise mechanism by which alcohol alters the developing brain.

The group's efforts mark one of the first times researchers have been able to quantify the effects of alcohol exposure on the developing brain.

"The paper provides important integrative results for the field of FASD," said Julia Stephen, an author on the paper. "These results may then indicate that simple sensory measures may provide sensitivity for brain deficits that affect the broader cognitive domain."

Previous attempts to study the brain circuitry in affected individuals have been hampered by the difficulty of drawing conclusions from complicated MEG data.

To get to the heart of the problem, members of the team developed a sophisticated computer technique called Cortical Start Spatio-Temporal multidipole analysis that could identify which areas of the brain were active when research subjects were in the MEG machine.

After data from 19 FASD patients and 21 subjects without FASDs was collected, the computational approach revealed several areas of the brain that showed impaired connectivity among the FASD group.

Subjects who were exposed to alcohol in the womb were more likely to have issues with connections through their corpus callosum, the band of brain tissue that connects the left and right halves of the brain. Deficits in this area have been reported in people with schizophrenia, multiple sclerosis, autism, depression and abnormalities in sensation.

"This work presents major evidence that children exposed to alcohol prenatally are at risk of suffering from impaired cognitive abilities and other secondary factors," said Lin Gao, an author on the paper. "Our study ... shows that there is no safe amount or safe stages during pregnancy for alcohol consumption."

The authors hope their work inspires other groups to conduct similarly collaborative research on disorders like FASDs that benefit from drawing together medical and computational fields.

ANN ARBOR--A new class of coatings that sheds ice effortlessly from even large surfaces has moved researchers closer to their decades-long goal of ice-proofing cargo ships, airplanes, power lines and other large structures.

The spray-on coatings, developed at the University of Michigan, cause ice to fall away from structures--regardless of their size--with just the force of a light breeze, or often the weight of the ice itself. A paper on the research is published in Science.

In a test on a mock power line, the coating shed ice immediately.

The researchers overcame a major limitation of previous ice-repellent coatings--while they worked well on small areas, researchers found in field testing that they didn't shed ice on very large surfaces as effectively as they had hoped. That's an issue, since ice tends to cause the biggest problems on the biggest surfaces--sapping efficiency, jeopardizing safety and necessitating costly removal.

They cleared this hurdle with a "beautiful demonstration of mechanics." Anish Tuteja, an associate professor of materials science and engineering, described how he and his colleagues turned to a property that isn't well-known in icing research.

"For decades, coating research has focused on lowering adhesion strength--the force per unit area required to tear a sheet of ice from a surface," Tuteja said. "The problem with this strategy is that the larger the sheet of ice, the more force is required. We found that we were bumping up against the limits of low adhesion strength, and our coatings became ineffective once the surface area got large enough."

The new coatings solve the problem by introducing a second strategy: low interfacial toughness, abbreviated LIT. Surfaces with low interfacial toughness encourage cracks to form between ice and the surface. And unlike breaking an ice sheet's surface adhesion, which requires tearing the entire sheet free, a crack only breaks the surface free along its leading edge. Once that crack starts, it can quickly spread across the entire iced surface, regardless of its size.

"Imagine pulling a rug across a floor," said Michael Thouless, the Janine Johnson Weins Professor of Engineering in mechanical engineering. "The larger the rug, the harder it is to move. You are resisted by the strength of the entire interface between the rug and floor. The frictional force is analogous to the interfacial strength.

"But now imagine there's a wrinkle in that rug. It's easy to keep pushing that wrinkle across the rug, regardless of how big the rug is. The resistance to propagating the wrinkle is analogous to the interfacial toughness that resists the propagation of a crack."

Thouless said the concept of interfacial toughness is well known in the field of fracture mechanics, where it underpins products like laminated surfaces and adhesive-based aircraft joints. But until now, it hadn't been applied in ice mitigation. The advance came when Thouless learned of Tuteja's previous work and saw an opportunity.

"Traditionally, fracture mechanics researchers only care about interfacial toughness, and ice mitigation researchers often only care about interfacial strength," Thouless said. "But both parameters are important for understanding adhesion.

"I pointed out to Anish that if he were to test increasing lengths of ice, he would find the failure load would rise while interfacial strength was important, but then plateau once toughness became important. Anish and his students tried the experiments and ended up with a really beautiful demonstration of the mechanics, and a new concept for ice adhesion."

To test the idea, Tuteja's team used a technique he honed during previous coating research. By mapping out the properties of a vast library of substances and adding interfacial toughness as well as adhesion strength to the equation, they were able to mathematically predict the properties of a coating without the need to physically test each one. This enabled them to concoct a wide variety of combinations, each with a specifically tailored balance between interfacial toughness and adhesion strength.

They tested a variety of coatings on large surfaces--a rigid aluminum sheet approximately 3 feet square, and a flexible aluminum piece approximately 1 inch wide and 3 feet long, to mimic a power line. On every surface, ice fell off immediately due to its own weight. It stuck fast, however, to the control surfaces, which were identical in size--one was uncoated and another was coated with an earlier icephobic coating.

The team's next step is to improve its durability of the LIT coatings.

Researchers at the Paul Scherrer Institute PSI have elucidated an important part of a signal pathway that transmits information through the cell membrane into the interior of a cell.

The interior of all living cells is separated from the outside world by membranes. These membranes keep the cells intact and protect them from negative influences. But they also act as a barrier for nutrients and information. For this reason, cell membranes contain mechanisms that enable selective access to desired substances or transmit information from external signals into the cell.

An important signal pathway in mammals consists of three components: The first is a receptor that recognises the signal and is activated by it. The second is a so-called G protein that binds to the activated receptor and transmits the signal to one or more effector proteins. In this case, the effector is adenylyl cyclase, the third component of the signal chain. This protein is activated by a subunit of the G protein and produces, in a biochemical reaction, a secondary messenger called cyclic AMP (cAMP).

cAMP triggers various reactions in the cell; for example, it increases the permeability of the membrane to calcium in cardiac cells, leading to an increase in the heart beat rate.

Researchers at the Paul Scherrer Institute in Villigen, Switzerland, have now examined one special type of adenylyl cyclase with the help of electron microscopy and have produced the most detailed image to date of this type of membrane protein.

Helpful self-restraint

"To understand how signal pathways in the cell work, it is necessary first to know what the components involved look like in detail", says Volodymyr Korkhov, head of the research group Mechanisms of Signal Transduction in the Biology and Chemistry Division at PSI and assistant professor at the Institute for Biochemistry at ETH Zurich. "Our work is an important contribution to elucidating the exact function of adenylyl cyclase in the cAMP signal chain."

"Surprisingly, in determining the structure of the adenylyl cyclase bound to the alpha subunit of the G protein, we discovered that the protein appears to be able to inhibit itself", says Korkhov. One part of the protein is responsible for this self-inhibition. This part blocks the active site of the enzyme and prevents the overproduction of cAMP.

This new insight into the molecular structure of adenylyl cyclase provides a much better understanding of how external signals lead to the controlled production of the important secondary messenger cAMP. The concentration of cAMP in cells plays an important role in the development of cardiovascular diseases, certain tumours, and type 2 diabetes. "In the future, our new findings could make it possible to identify drugs that inhibit or activate the adenylyl cyclase, depending on whether overproduction or lack of cAMP is responsible for a disease", Korkhov explains.

Microscopy at low temperatures

The researchers achieved their results using cryo-electron microscopy (cryo-EM). This form of transmission electron microscopy operates at temperatures below -150 degrees Celsius. The sample to be examined is snap frozen in liquid ethane, preserving its natural structure. This method, for which the Nobel Prize for Chemistry was awarded in 2017, is increasingly used in the investigation of biological structures. "It is exciting to get a deep insight into the structure of adenylate cyclase", says Chao Qi, a doctoral candidate in Korkhov's lab and first author of the study. "The structure of this protein has been elusive for decades since its discovery, and I'm glad that I was able to elucidate this structure with cryo-EM in the course of my doctoral research."

The resolution achieved by the PSI researchers in their investigations was 3.4 angstroms. An angstrom is one ten-millionth of a millimetre. Isolated atoms have a radius of 0.3 to 3 angstroms.

The researchers have now published their findings in the scientific journal Science.

Over the last three decades, wind speeds and wave heights have increased, even if just a little, in most places around the world, with the greatest increases occurring in the Southern Ocean.

The new study reporting these results used global satellite data spanning more than thirty years, from 1985 to 2018. The analysis helps to refine the understanding of how these critical oceanic and atmospheric processes are influenced by the changing climate. Oceanic wind and wave patterns play an important role in a number of environmental and climate systems. Wind over open waters largely defines the roughness of the surface, which can greatly influence the transfer of both energy and carbon dioxide between the atmosphere and ocean. Also, wave heights can affect storm surge levels and coastal flooding during extreme weather events. The ability to determine small changes in global trends of winds and waves using long-term wind and wave records has remained challenging, however. Differences in the instrumentation of ocean buoys limit their ability to provide suitable data and concerns about the consistency of global satellite data have not yet been fully addressed.

Here, Ian Young and Agustinus Ribal took advantage of an extensive satellite database of wind speed and wave heights spanning more than thirty years (1985-2018). The dataset combines measurements from three independent instruments: altimeters (measuring wave height and wind speed), radiometers (measuring wind speed) and scatterometers (measuring wind speed and direction). Analyses of the resulting data show small, yet significant increases in global wind speed and wave heights, particularly during extreme conditions. Young and Ribal also find strong regional variations in these positive trends, with the Southern Ocean exhibiting the most significant increases, while trends in the equatorial Pacific and North Atlantic are much weaker.

According to the authors, the findings were confirmed across each satellite instrument, which suggests no negative impacts caused by inconsistent data or sampling patterns.

A new fossil from the dinosaur era challenges the understanding of evolution. In a paper published in Science Advances, an international team, including researchers from the Smithsonian Tropical Research Institute (STRI) in Panama, announced their discovery of a new fossil crab species, Callichimaera perplexa in Boyacá, Colombia, and in Wyoming in the United States.

"This new discovery is one of the most exciting fossil findings in the tropics in the past decade," said Javier Luque, former predoctoral fellow in staff scientist Carlos Jaramillo's lab at STRI, now NSERC postdoctoral fellow in the Department of Geology and Geophysics at Yale University. "We discovered a treasure trove of fossil crabs, dozens of exceptionally preserved specimens with eyes, antennae, muscles and reproductive organs."

Sometimes it is difficult to piece together the tree of life that maps the evolution of the animals seen today. Important pieces in the puzzle may be rare or yet to be discovered. According to the authors, this fossil crab's unique body form pushes the textbook definition of what a crab is. It has large, unprotected compound eyes, a small body and mouthparts that look like legs. Its large, oar-like legs are the oldest record of adaptations of crabs for swimming.

"This baffling fossil is like the platypus of the crab world," Luque said. "It is the earliest arthropod to evolve swimming oar-like legs since the sea scorpions disappeared more than 250 million years ago, a beautiful and perplexing chimera, as its name indicates."

By comparing specimens of the new species with all known crab species, the team discovered several important unique characteristics of this species that sets it apart. The adults have characteristics similar to crab larvae. This would be like an adult human having the disproportionately large eyes of a baby, for example. Because researchers found males and females, they concluded that they were seeing adults, even though they appeared to have many characteristics of an earlier life-stage. The phenomenon of an adult retaining characteristics of a younger form is called pedomorphosis, a way to skip evolutionary steps in order to adapt to a new environment in fewer generations.

"This reveals a new branch in the tree of life that has never been seen before," said Jaramillo, project advisor.