Tag Archives: Carnegie Mellon University (CMU)

Should robots have rights? Confucianism offers some ideas

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Fascinating although I’m not sure I entirely understand his argument,

This May 24, 2023 Carnegie Mellon University (CMU) news release (also on EurekAlert but published May 25, 2023) has Professor Tae Wan Kim’s clarification, Note: Links have been removed,

Philosophers and legal scholars have explored significant aspects of the moral and legal status of robots, with some advocating for giving robots rights. As robots assume more roles in the world, a new analysis reviewed research on robot rights, concluding that granting rights to robots is a bad idea. Instead, the article looks to Confucianism to offer an alternative.

The analysis, by a researcher at Carnegie Mellon University (CMU), appears in Communications of the ACM, published by the Association for Computing Machinery.

“People are worried about the risks of granting rights to robots,” notes Tae Wan Kim, Associate Professor of Business Ethics at CMU’s Tepper School of Business, who conducted the analysis. “Granting rights is not the only way to address the moral status of robots: Envisioning robots as rites bearers—not a rights bearers—could work better.”

Although many believe that respecting robots should lead to granting them rights, Kim argues for a different approach. Confucianism, an ancient Chinese belief system, focuses on the social value of achieving harmony; individuals are made distinctively human by their ability to conceive of interests not purely in terms of personal self-interest, but in terms that include a relational and a communal self. This, in turn, requires a unique perspective on rites, with people enhancing themselves morally by participating in proper rituals.

When considering robots, Kim suggests that the Confucian alternative of assigning rites—or what he calls role obligations—to robots is more appropriate than giving robots rights. The concept of rights is often adversarial and competitive, and potential conflict between humans and robots is concerning.

“Assigning role obligations to robots encourages teamwork, which triggers an understanding that fulfilling those obligations should be done harmoniously,” explains Kim. “Artificial intelligence (AI) imitates human intelligence, so for robots to develop as rites bearers, they must be powered by a type of AI that can imitate humans’ capacity to recognize and execute team activities—and a machine can learn that ability in various ways.”

Kim acknowledges that some will question why robots should be treated respectfully in the first place. “To the extent that we make robots in our image, if we don’t treat them well, as entities capable of participating in rites, we degrade ourselves,” he suggests.

Various non-natural entities—such as corporations—are considered people and even assume some Constitutional rights. In addition, humans are not the only species with moral and legal status; in most developed societies, moral and legal considerations preclude researchers from gratuitously using animals for lab experiments.

Here’s a link to and a citation for the paper,

Should Robots Have Rights or Rites? by Tae Wan Kim, Alan Strudler. Communications of the ACM, June 2023, Vol. 66 No. 6, Pages 78-85 DOI: 10.1145/3571721

This work is licensed under a http://creativecommons.org/licenses/by/4.0/ In other words, this paper is open access.

The paper is quite readable, as academic papers go, (Note: Links have been removed),

Boston Dynamics recently released a video introducing Atlas, a six-foot bipedal humanoid robot capable of search and rescue missions. Part of the video contained employees apparently abusing Atlas (for example, kicking, hitting it with a hockey stick, pushing it with a heavy ball). The video quickly raised a public and academic debate regarding how humans should treat robots. A robot, in some sense, is nothing more than software embedded in hardware, much like a laptop computer. If it is your property and kicking it harms no one nor infringes on anyone’s rights, it’s okay to kick it, although that would be a stupid thing to do. Likewise, there seems to be no significant reason that kicking a robot should be deemed as a moral or legal wrong. However, the question—”What do we owe to robots?”—is not that simple. Philosophers and legal scholars have seriously explored and defended some significant aspects of the moral and legal status of robots—and their rights.3,6,15,16,24,29,36 In fact, various non-natural entities—for example, corporations—are treated as persons and even enjoy some constitutional rights.a In addition, humans are not the only species that get moral and legal status. In most developed societies, for example, moral and legal considerations preclude researchers from gratuitously using animals for lab experiments. The fact that corporations are treated as persons and animals are recognized as having some rights does not entail that robots should be treated analogously.

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Connie Lin’s May 26, 2023 article for Fast Company “Confucianism for robots? Ethicist says that’s better than giving them full rights” offers a brief overview and more comments from Kim. For the curious, you find out more about Boston Dynamics and Atlas here.

International conference “Living Machines” dedicated to technology inspired by nature in Genoa, Italy (July 10 – 13, 2023)

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I love the look and the theme for this “Living Machines” conference, which seems to be water,

A June 28, 2023 Istituto Italiano di Tecnologia (IIT) press release (also on EurekAlert) provides more detail about the conference,

Now in its twelfth year, the international conference “Living Machines”, organised by Istituto Italiano di Tecnologia (Italian Institute of Technology, IIT), returns to Italy and comes to Genoa for the first time, from 10 to 13 July. Around one hundred experts from all over the world are expected, and they will present their achievements in the field of bio-inspired science and technology. The conference will take place in an exceptional venue, the Acquario di Genova (Genoa Aquarium), which, having reached its 30th birthday, is the ideal location at which to bring together various subject areas, from biology to artificial intelligence and robotics, with a focus on sustainability and environmental protection.

The scientific organiser of the event is Barbara Mazzolai, Associate Director for Robotics and head of the Bioinspired Soft Robotics Lab at IIT, along with Fabian Meder, researcher in the Bioinspired Soft Robotics Lab group and co-chair of the conference programme.

The conference will include two events open to the public: an exhibition area, which will be accessible from 11 to 13 July in the afternoon (from 2 to 4.30 pm); and a scientific café, which will take place on the 12 July at 5 pm. The conference will be an opportunity for international guests to appreciate the region’s beauty and talents, and it will also include the participation of students from the Niccolò Paganini Conservatory of Music. In addition, a satellite event of the conference will be the ISPA – Italian Sustainability Photo Award – exhibition, which will open at Palazzo Ducale on 10 July at 6 p.m.

The “Living Machines” conference is the landmark event for the international scientific community which bases its research on living organisms, such as human beings and other animal species – terrestrial, marine, and airborne – in addition to plants, fungi, and bacteria, in order to create so-called “living machines”, in other words, forms of technology capable of replicating their structure and mechanisms of operation.

“The conference is rooted in the union between robotics and neuroscience, using man and other animal species as a model for the study of intelligence and control systems,” said Barbara Mazzolai, Associate Director for Robotics at IIT. “This year the conference will focus on the role of biomimicry in the creation of robots that are more sustainable, with applications for the challenges of environmental protection and human health. Discussions will revolve around the development of robots with a lower energy impact, made using recyclable and biodegradable materials, and that can be used in emergency situations or extreme environments, such as deep sea, soil, space, or environmental disasters, but also for precision agriculture, environmental surveillance, infrastructure monitoring, human care and medical-surgical assistance.”

In the conference programme, experts will take part in a first day of parallel workshop and tutorial sessions (on 10 July), during which the topics of bioinspiration and biohybrid technology in the fields of medicine and the marine environment will be addressed. This first day will be followed by three days of plenary sessions, featuring talks by internationally-renowned scientists. More specifically: Oussama Khatib, one of the pioneers of robotics and director of the Robotics Laboratory at Stanford University; Marco Dorigo, professor at the Université Libre de Bruxelles and one of the pioneers of collective intelligence; Peter Fratzl, director of the Max Planck Institute of Colloids and Interfaces, working on research into osteoporosis and tissue regeneration; Eleni Stavrinidou, coordinator of the “Electronic Plants” group at Linköping University and an expert in bioelectronic and biohybrid systems; Olga Speck, Principal Researcher at the University of Freiburg, specialising in biomimetic materials and the regenerative capabilities of plants; and Kyu-Jin Cho, director of the Research Centre for Soft Robotics and the Biorobotics Laboratory at Seoul National University, one of the world’s leading experts on soft robotics.

For conference participants only, the programme includes: a visit to the Acquario, guided by the facility’s scientific staff, who will illustrate the work and practices needed for the protection and conservation of marine species and the undergoing research projects; an exhibition area for prototypes and products by research groups and companies operating in this field; and a dinner at Villa Lo Zerbino, with a musical contribution by students from the Niccolò Paganini Conservatory.

Open to the general public, on 12 July from 5 p.m. to 6 p.m. there will be a round table entitled “Living Machines: The Origin and the Future” chaired by science journalist Nicola Nosengo, Chief Editor of Nature Italy. Speakers will include Cecilia Laschi from the National University of Singapore, Vickie Webster-Wood from Carnegie Mellon University, Thomas Speck from the University of Freiburg and Paul Verschure from Radboud University Nijmegen.

A satellite initiative of the conference will be the exhibition for ISPA, the Italian Sustainability Photo Award, which will open at Palazzo Ducale on 10 July at 6.00 p.m. ISPA is the photographic award created by the Parallelozero agency in cooperation with the main sponsor PIMCO, to raise public awareness of environmental, social, and governance sustainability issues, encapsulated in the acronym ESG. The works of the winning photographers and finalists in the last three editions will be on display in Genoa: a selection of images that depict the emblematic stories of Italy, a nation moving towards a more sustainable future, a visual narrative that makes it easier to understand the country’s progress in research and innovation.

The organisations supporting the event include, in addition to the principal organiser Istituto Italiano di Tecnologia (Italian Institute of Technology), the international Convergent Science Network [emphasis mine], the Office of Naval Research, Radboud University Nijmegen, and the Living, Adaptive and Energy-autonomous Materials Systems Cluster of Excellence in Freiburg.

Event website: https://livingmachinesconference.eu/2023/

I was particularly struck by this quote, “The conference is rooted in the union between robotics and neuroscience [emphasis mine], using man and other animal species as a model for the study of intelligence and control systems,” from Barbara Mazzolai as I have an as yet unpublished post for a UNESCO neurotechnology event coming up on July 13, 2023. These events come on the heels of a May 16, 2023 Canadian Science Policy Centre panel discussion on responsible neurotechnology (see my May 12, 2023 posting).

For the curious, you can find the Convergent Science Network here.

Implantable living pharmacy

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I stumbled across a very interesting US Defense Advanced Research Projects Agency (DARPA) project (from an August 30, 2021 posting on Northwestern University’s Rivnay Lab [a laboratory for organic bioelectronics] blog),

Our lab has received a cooperative agreement with DARPA to develop a wireless, fully implantable ‘living pharmacy’ device that could help regulate human sleep patterns. The project is through DARPA’s BTO (biotechnology office)’s Advanced Acclimation and Protection Tool for Environmental Readiness (ADAPTER) program, meant to address physical challenges of travel, such as jetlag and fatigue.

The device, called NTRAIN (Normalizing Timing of Rhythms Across Internal Networks of Circadian Clocks), would control the body’s circadian clock, reducing the time it takes for a person to recover from disrupted sleep/wake cycles by as much as half the usual time.

The project spans 5 institutions including Northwestern, Rice University, Carnegie Mellon, University of Minnesota, and Blackrock Neurotech.

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Prior to the Aug. 30, 2021 posting, Amanda Morris wrote a May 13, 2021 article for Northwestern NOW (university magazine), which provides more details about the project, Note: A link has been removed,

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The first phase of the highly interdisciplinary program will focus on developing the implant. The second phase, contingent on the first, will validate the device. If that milestone is met, then researchers will test the device in human trials, as part of the third phase. The full funding corresponds to $33 million over four-and-a-half years. 

Nicknamed the “living pharmacy,” the device could be a powerful tool for military personnel, who frequently travel across multiple time zones, and shift workers including first responders, who vacillate between overnight and daytime shifts.

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Combining synthetic biology with bioelectronics, the team will engineer cells to produce the same peptides that the body makes to regulate sleep cycles, precisely adjusting timing and dose with bioelectronic controls. When the engineered cells are exposed to light, they will generate precisely dosed peptide therapies. 

“This control system allows us to deliver a peptide of interest on demand, directly into the bloodstream,” said Northwestern’s Jonathan Rivnay, principal investigator of the project. “No need to carry drugs, no need to inject therapeutics and — depending on how long we can make the device last — no need to refill the device. It’s like an implantable pharmacy on a chip that never runs out.” 

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Beyond controlling circadian rhythms, the researchers believe this technology could be modified to release other types of therapies with precise timing and dosing for potentially treating pain and disease. The DARPA program also will help researchers better understand sleep/wake cycles, in general.

“The experiments carried out in these studies will enable new insights into how internal circadian organization is maintained,” said Turek [Fred W. Turek], who co-leads the sleep team with Vitaterna [Martha Hotz Vitaterna]. “These insights will lead to new therapeutic approaches for sleep disorders as well as many other physiological and mental disorders, including those associated with aging where there is often a spontaneous breakdown in temporal organization.” 

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For those who like to dig even deeper, Dieynaba Young’s June 17, 2021 article for Smithsonian Magazine (GetPocket.com link to article) provides greater context and greater satisfaction, Note: Links have been removed,

In 1926, Fritz Kahn completed Man as Industrial Palace, the preeminent lithograph in his five-volume publication The Life of Man. The illustration shows a human body bustling with tiny factory workers. They cheerily operate a brain filled with switchboards, circuits and manometers. Below their feet, an ingenious network of pipes, chutes and conveyer belts make up the blood circulatory system. The image epitomizes a central motif in Kahn’s oeuvre: the parallel between human physiology and manufacturing, or the human body as a marvel of engineering.

An apparatus in the embryonic stage of development at the time of this writing in June of 2021—the so-called “implantable living pharmacy”—could have easily originated in Kahn’s fervid imagination. The concept is being developed by the Defense Advanced Research Projects Agency (DARPA) in conjunction with several universities, notably Northwestern and Rice. Researchers envision a miniaturized factory, tucked inside a microchip, that will manufacture pharmaceuticals from inside the body. The drugs will then be delivered to precise targets at the command of a mobile application. …

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The implantable living pharmacy, which is still in the “proof of concept” stage of development, is actually envisioned as two separate devices—a microchip implant and an armband. The implant will contain a layer of living synthetic cells, along with a sensor that measures temperature, a short-range wireless transmitter and a photo detector. The cells are sourced from a human donor and reengineered to perform specific functions. They’ll be mass produced in the lab, and slathered onto a layer of tiny LED lights.

The microchip will be set with a unique identification number and encryption key, then implanted under the skin in an outpatient procedure. The chip will be controlled by a battery-powered hub attached to an armband. That hub will receive signals transmitted from a mobile app.

If a soldier wishes to reset their internal clock, they’ll simply grab their phone, log onto the app and enter their upcoming itinerary—say, a flight departing at 5:30 a.m. from Arlington, Virginia, and arriving 16 hours later at Fort Buckner in Okinawa, Japan. Using short-range wireless communications, the hub will receive the signal and activate the LED lights inside the chip. The lights will shine on the synthetic cells, stimulating them to generate two compounds that are naturally produced in the body. The compounds will be released directly into the bloodstream, heading towards targeted locations, such as a tiny, centrally-located structure in the brain called the suprachiasmatic nucleus (SCN) that serves as master pacemaker of the circadian rhythm. Whatever the target location, the flow of biomolecules will alter the natural clock. When the solider arrives in Okinawa, their body will be perfectly in tune with local time.

The synthetic cells will be kept isolated from the host’s immune system by a membrane constructed of novel biomaterials, allowing only nutrients and oxygen in and only the compounds out. Should anything go wrong, they would swallow a pill that would kill the cells inside the chip only, leaving the rest of their body unaffected.

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If you have the time, I recommend reading Young’s June 17, 2021 Smithsonian Magazine article (GetPocket.com link to article) in its entirety. Young goes on to discuss, hacking, malware, and ethical/societal issues and more.

There is an animation of Kahn’s original poster in a June 23, 2011 posting on openculture.com (also found on Vimeo; Der Mensch als Industriepalast [Man as Industrial Palace])

Credits: Idea & Animation: Henning M. Lederer / led-r-r.net; Sound-Design: David Indge; and original poster art: Fritz Kahn.

In Brazil: Applications open for July 3 – 15, 2023 School of Advanced Science on Nanotechnology, Agriculture and Environment

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According to the December 15, 2022 Fundação de Amparo à Pesquisa do Estado de São Paulo press release on EurekAlert applications will be received until February 5, 2023,

The São Paulo School of Advanced Science on Nanotechnology, Agriculture and Environment (SPSAS NanoAgri&Enviro) will be held on July 3-15 at the Brazilian Center for Research in Energy and Materials (CNPEM) in Campinas, São Paulo state, Brazil. 

Reporters are invited to reach the organizing committee through the email eventos@cnpem.br, for opportunities to visit the school and sessions.

Designed to meet an increasing level of content depth and complexity, the SPSAS NanoAgri&Enviro will cover the following topics: i) Nanotechnology, innovation, and sustainability; ii) Synthesis, functionalization, and characterization of nanomaterials; iii) Characterization of nanoparticles in complex matrices; iv) Synchrotron Light for nano-agri-environmental research; v) Biological and environmental applications of nanoparticles; vi) Nanofertilizers and Nanoagrochemicals; vii) Ecotoxicology, geochemistry and nanobiointerfaces; viii) Nanosafety and Nanoinformatics; ix) International harmonization and regulatory issues; x) Environmental implications of nanotechnology.

Discussions regarding those topics will benefit from the participation of internationally renowned scientists as speakers, including Mark V. Wiesner (Duke University), Iseult Lynch (University of Birmingham), Leonardo F. Fraceto (São Paulo State University – UNESP), Gregory V. Lowry (Carnegie Mellon University), Marisa N. Fernandes (Federal University of São Carlos – UFSCar), Caue Ribeiro (Brazilian Agricultural Research Corporation – EMBRAPA), and others.

The program also comprise didactic activities programmed among theoretical interactive classes, practical experiments (hands-on), and technical visits to world-class facilities and specialized laboratories from several institutions in São Paulo state.

The São Paulo Research Foundation (FAPESP) is supporting the event through its São Paulo School of Advanced Science Program (SPSAS http://espca.fapesp.br/home). Undergraduate students, postdoctoral fellows and researchers who are already working on subjects relating to the school can apply to receive financial support to cover the cost of air travel, accommodation and meals. Applications must be submitted by February 5, 2023.

More information: https://pages.cnpem.br/spsasnano/.

I looked up the criteria for eligible applicants and found this among the other criteria (from the Applications page),

Participating students must be enrolled in undergraduate or graduate courses in Brazil or abroad, being potential candidates for Master’s, Doctoral or Post-Doctoral internships in higher education and research institutions in the state of São Paulo. Doctors may also be accepted. [emphases mine]

If I read that correctly, it means that people who are considering or planning to further their studies in the state of São Paulo are being invited to apply.

I recognized two of the speakers’ names, Mark Wiesner and Iseult Lynch both of whom have been mentioned here a number of times as has Gregory V. Lowry. (Wiesner very kindly helped with an art/sci project I was involved with [Steep] a number of years ago.)

Good luck with your application!

Just swallow your battery, eh? Ingestible batteries

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Christopher Bettinger, Ph.D., is developing an edible battery made with melanin and dissolvable materials. Courtesy of: Bettinger lab

Christopher Bettinger, Ph.D., is developing an edible battery made with melanin and dissolvable materials. Courtesy of: Bettinger lab

An Aug. 23, 2016 news item on phys.org describes a session at the 252nd American Chemical Society (ACS) meeting held Aug. 21 – 25, 2016 in Philadelphia,

Non-toxic, edible batteries could one day power ingestible devices for diagnosing and treating disease. One team reports new progress toward that goal with their batteries made with melanin pigments, naturally found in the skin, hair and eyes.

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“For decades, people have been envisioning that one day, we would have edible electronic devices to diagnose or treat disease,” says Christopher Bettinger, Ph.D. “But if you want to take a device every day, you have to think about toxicity issues. That’s when we have to think about biologically derived materials that could replace some of these things you might find in a RadioShack.”

An Aug. 23, 2016 ACS news release (also on EurekAlert), which originated the news item, further describes the work featured in the ACS meeting session,

About 20 years ago, scientists did develop a battery-operated ingestible camera as a complementary tool to endoscopies. It can image places in the digestive system that are inaccessible to the traditional endoscope. But it is designed to pass through the body and be excreted. For a single use, the risk that the camera with a conventional battery will get stuck in the gastrointestinal tract is small. But the chances of something going wrong would increase unacceptably if doctors wanted to use it more frequently on a single patient.

The camera and some implantable devices such as pacemakers run on batteries containing toxic components that are sequestered away from contact with the body. But for low-power, repeat applications such as drug-delivery devices that are meant to be swallowed, non-toxic and degradable batteries would be ideal.

“The beauty is that by definition an ingestible, degradable device is in the body for no longer than 20 hours or so,” Bettinger says. “Even if you have marginal performance, which we do, that’s all you need.”

While he doesn’t have to worry about longevity, toxicity is an issue. To minimize the potential harm of future ingestible devices, Bettinger’s team at Carnegie Mellon University (CMU) decided to turn to melanins and other naturally occurring compounds. In our skin, hair and eyes, melanins absorb ultraviolet light to quench free radicals and protect us from damage. They also happen to bind and unbind metallic ions. “We thought, this is basically a battery,” Bettinger says.

Building on this idea, the researchers experimented with battery designs that use melanin pigments at either the positive or negative terminals; various electrode materials such as manganese oxide and sodium titanium phosphate; and cations such as copper and iron that the body uses for normal functioning.

“We found basically that they work,” says Hang-Ah Park, Ph.D., a post-doctoral researcher at CMU. “The exact numbers depend on the configuration, but as an example, we can power a 5 milliWatt device for up to 18 hours using 600 milligrams of active melanin material as a cathode.”

Although the capacity of a melanin battery is low relative to lithium-ion, it would be high enough to power an ingestible drug-delivery or sensing device. For example, Bettinger envisions using his group’s battery for sensing gut microbiome changes and responding with a release of medicine, or for delivering bursts of a vaccine over several hours before degrading.

In parallel with the melanin batteries, the team is also making edible batteries with other biomaterials such as pectin, a natural compound from plants used as a gelling agent in jams and jellies. Next, they plan on developing packaging materials that will safely deliver the battery to the stomach.

When these batteries will be incorporated into biomedical devices is uncertain, but Bettinger has already found another application for them. His lab uses the batteries to probe the structure and chemistry of the melanin pigments themselves to better understand how they work.

I previously wrote about an ingestible battery in a November 23, 2015 posting featuring work from MIT (Massachusetts Institute of Technology).

Accountability for artificial intelligence decision-making

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How does an artificial intelligence program arrive at its decisions? It’s a question that’s not academic any more as these programs take on more decision-making chores according to a May 25, 2016 Carnegie Mellon University news release (also on EurekAlert) by Bryon Spice (Note: Links have been removed),

Machine-learning algorithms increasingly make decisions about credit, medical diagnoses, personalized recommendations, advertising and job opportunities, among other things, but exactly how usually remains a mystery. Now, new measurement methods developed by Carnegie Mellon University [CMU] researchers could provide important insights to this process.

Was it a person’s age, gender or education level that had the most influence on a decision? Was it a particular combination of factors? CMU’s Quantitative Input Influence (QII) measures can provide the relative weight of each factor in the final decision, said Anupam Datta, associate professor of computer science and electrical and computer engineering.

It’s reassuring to know that more requests for transparency of the decision-making process are being made. After all, it’s disconcerting that someone with the life experience of a gnat and/or possibly some issues might be developing an algorithm that could affection your life in some fundamental ways. Here’s more from the news release (Note: Links have been removed),

“Demands for algorithmic transparency are increasing as the use of algorithmic decision-making systems grows and as people realize the potential of these systems to introduce or perpetuate racial or sex discrimination or other social harms,” Datta said.

“Some companies are already beginning to provide transparency reports, but work on the computational foundations for these reports has been limited,” he continued. “Our goal was to develop measures of the degree of influence of each factor considered by a system, which could be used to generate transparency reports.”

These reports might be generated in response to a particular incident — why an individual’s loan application was rejected, or why police targeted an individual for scrutiny, or what prompted a particular medical diagnosis or treatment. Or they might be used proactively by an organization to see if an artificial intelligence system is working as desired, or by a regulatory agency to see whether a decision-making system inappropriately discriminated between groups of people.

Datta, along with Shayak Sen, a Ph.D. student in computer science, and Yair Zick, a post-doctoral researcher in the Computer Science Department, will present their report on QII at the IEEE Symposium on Security and Privacy, May 23–25 [2016], in San Jose, Calif.

Generating these QII measures requires access to the system, but doesn’t necessitate analyzing the code or other inner workings of the system, Datta said. It also requires some knowledge of the input dataset that was initially used to train the machine-learning system.

A distinctive feature of QII measures is that they can explain decisions of a large class of existing machine-learning systems. A significant body of prior work takes a complementary approach, redesigning machine-learning systems to make their decisions more interpretable and sometimes losing prediction accuracy in the process.

QII measures carefully account for correlated inputs while measuring influence. For example, consider a system that assists in hiring decisions for a moving company. Two inputs, gender and the ability to lift heavy weights, are positively correlated with each other and with hiring decisions. Yet transparency into whether the system uses weight-lifting ability or gender in making its decisions has substantive implications for determining if it is engaging in discrimination.

“That’s why we incorporate ideas for causal measurement in defining QII,” Sen said. “Roughly, to measure the influence of gender for a specific individual in the example above, we keep the weight-lifting ability fixed, vary gender and check whether there is a difference in the decision.”

Observing that single inputs may not always have high influence, the QII measures also quantify the joint influence of a set of inputs, such as age and income, on outcomes and the marginal influence of each input within the set. Since a single input may be part of multiple influential sets, the average marginal influence of the input is computed using principled game-theoretic aggregation measures previously applied to measure influence in revenue division and voting.

“To get a sense of these influence measures, consider the U.S. presidential election,” Zick said. “California and Texas have influence because they have many voters, whereas Pennsylvania and Ohio have power because they are often swing states. The influence aggregation measures we employ account for both kinds of power.”

The researchers tested their approach against some standard machine-learning algorithms that they used to train decision-making systems on real data sets. They found that the QII provided better explanations than standard associative measures for a host of scenarios they considered, including sample applications for predictive policing and income prediction.

Now, they are seeking collaboration with industrial partners so that they can employ QII at scale on operational machine-learning systems.

Here’s a link to and a citation for a PDF of the paper presented at the May 2016 conference,

Algorithmic Transparency via Quantitative Input Influence: Theory and Experiments with Learning Systems by Anupam Datta, Shayak Sen, Yair Zick. Presented at the at the IEEE Symposium on Security and Privacy, May 23–25, in San Jose, Calif.

I’ve also embedded the paper here,

CarnegieMellon_AlgorithmicTransparency

Gold atoms: sometimes they’re a metal and sometimes they’re a molecule

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Fascinating work out of Finland shows that a minor change in the number of gold atoms in your gold nanoparticle can mean the difference between a metal and a molecule (coincidentally, this phenomenon is alluded to in my April 14, 2015 post (Nature’s patterns reflected in gold nanoparticles); more about that at the end of this piece. Getting back to Finland and when gold is metal and when it’s a molecule, here’s more from an April 10, 2015 news item on ScienceDaily,

Researchers at the Nanoscience Center at the University of Jyväskylä, Finland, have shown that dramatic changes in the electronic properties of nanometre-sized chunks of gold occur in well-defined size range. Small gold nanoclusters could be used, for instance, in short-term storage of energy or electric charge in the field of molecular electronics. Funded by the Academy of Finland, the researchers have been able to obtain new information which is important, among other things, in developing bioimaging and sensing based on metal-like clusters.

An April 10, 2015 news release (also on EurekAlert) on the Academy of Finland (Suomen Akatemia) website, which originated the news item, describes the work in more detail,

Two recent papers by the researchers at Jyväskylä (1, 2) demonstrate that the electronic properties of two different but still quite similar gold nanoclusters can be drastically different. The clusters were synthesised by chemical methods incorporating a stabilising ligand layer on their surface. The researchers found that the smaller cluster, with up to 102 gold atoms, behaves like a giant molecule while the larger one, with at least 144 gold atoms, already behaves, in principle, like a macroscopic chunk of metal, but in nanosize.

The fundamentally different behaviour of these two differently sized gold nanoclusters was demonstrated by shining a laser light onto solution samples containing the clusters and by monitoring how energy dissipates from the clusters into the surrounding solvent.

“Molecules behave drastically different from metals,” said Professor Mika Pettersson, the principal investigator of the team conducting the experiments. “The additional energy from light, absorbed by the metal-like clusters, transfers to the environment extremely rapidly, in about one hundred billionth of a second, while a molecule-like cluster is excited to a higher energy state and dissipates the energy into the environment with a rate that is at least 100 times slower. This is exactly what we saw: the 102-gold atom cluster is a giant molecule showing even a transient magnetic state while the 144-gold atom cluster is already a metal. We’ve thus managed to bracket an important size region where this fundamentally interesting change in the behaviour takes place.”

“These experimental results go together very well with what our team has seen from computational simulations on these systems,” said Professor Hannu Häkkinen, a co-author of the studies and the scientific director of the nanoscience centre. “My team predicted this kind of behaviour back in 2008-2009 when we saw big differences in the electronic structure of exactly these nanoclusters. It’s wonderful that robust spectroscopic experiments have now proved these phenomena. In fact, the metal-like 144-atom cluster is even more interesting, since we just published a theoretical paper where we saw a big enhancement of the metallic properties of just a few copper atoms mixed with gold.” (3)

Here are links to and citation for the papers,

Ultrafast Electronic Relaxation and Vibrational Cooling Dynamics of Au144(SC2H4Ph)60 Nanocluster Probed by Transient Mid-IR Spectroscopy by Satu Mustalahti, Pasi Myllyperkiö, Tanja Lahtinen, Kirsi Salorinne, Sami Malola, Jaakko Koivisto, Hannu Häkkinen, and Mika Pettersson. J. Phys. Chem. C, 2014, 118 (31), pp 18233–18239 DOI: 10.1021/jp505464z Publication Date (Web): July 3, 2014

Copyright © 2014 American Chemical Society

Copper Induces a Core Plasmon in Intermetallic Au(144,145)–xCux(SR)60 Nanoclusters by Sami Malola, Michael J. Hartmann, and Hannu Häkkinen. J. Phys. Chem. Lett., 2015, 6 (3), pp 515–520 DOI: 10.1021/jz502637b Publication Date (Web): January 22, 2015

Copyright © 2015 American Chemical Society

Molecule-like Photodynamics of Au102(pMBA)44 Nanocluster by Satu Mustalahti, Pasi Myllyperkiö, Sami Malola, Tanja Lahtinen, Kirsi Salorinne, Jaakko Koivisto, Hannu Häkkinen, and Mika Pettersson. ACS Nano, 2015, 9 (3), pp 2328–2335 DOI: 10.1021/nn506711a Publication Date (Web): February 22, 2015

Copyright © 2015 American Chemical Society

These papers are behind paywalls.

As for my April 14, 2015 post (Nature’s patterns reflected in gold nanoparticles), researchers at Carnegie Mellon University were researching patterns in different sized gold nanoparticles when this was noted in passing,

… Normally, gold is one of the best conductors of electrical current, but the size of Au133 is so small that the particle hasn’t yet become metallic. …

Nature’s patterns reflected in gold nanoparticles

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A 133 atom gold nanoparticle bears a resemblance to the Milky Way and to DNA’s (deoxyribonucleic acid) double helix according to an April 9, 2015 news item on ScienceDaily,

Our world is full of patterns, from the twist of a DNA molecule to the spiral of the Milky Way. New research from Carnegie Mellon chemists has revealed that tiny, synthetic gold nanoparticles exhibit some of nature’s most intricate patterns.

Unveiling the kaleidoscope of these patterns was a Herculean task, and it marks the first time that a nanoparticle of this size has been crystallized and its structure mapped out atom by atom. The researchers report their work in the March 20  [2015] issue of Science Advances.

“As you broadly think about different research areas or even our everyday lives, these kinds of patterns, these hierarchical patterns, are universal,” said Rongchao Jin, associate professor of chemistry. “Our universe is really beautiful and when you see this kind of information in something as small as a 133-atom nanoparticle and as big as the Milky Way, it’s really amazing.”

An April 8, 2015 Carnegie Mellon University news release (also on EurekAlert but dated April 9) by Jocelyn Duffy, which originated the news release, offers a description of gold nanoparticles along with details about the research,

Gold nanoparticles, which can vary in size from 1 to 100 nanometers, are a promising technology that has applications in a wide range of fields including catalysis, electronics, materials science and health care. But, in order to use gold nanoparticles in practical applications, scientists must first understand the tiny particles’ structure.

“Structure essentially determines the particle’s properties, so without knowing the structure, you wouldn’t be able to understand the properties and you wouldn’t be able to functionalize them for specific applications,” said Jin, an expert in creating atomically precise gold nanoparticles.

With this latest research, Jin and his colleagues, including graduate student Chenjie Zeng, have solved the structure of a nanoparticle, Au133, made up of 133 gold atoms and 52 surface-protecting molecules—the biggest nanoparticle structure ever resolved with X-ray crystallography. While microscopy can reveal the size, shape and the atomic lattice of nanoparticles, it can’t discern the surface structure. X-ray crystallography can, by mapping out the position of every atom on the nanoparticles’ surface and showing how they bond with the gold core. Knowing the surface structure is key to using the nanoparticles for practical applications, such as catalysis, and for uncovering fundamental science, such as the basis of the particle’s stability.

The crystal structure of the Au133 nanoparticle divulged many secrets.

“With X-ray crystallography, we were able to see very beautiful patterns, which was a very exciting discovery. These patterns only show up when the nanoparticle size becomes big enough,” Jin said.

During production, the Au133 particles self-assemble into three layers within each particle: the gold core, the surface molecules that protect it and the interface between the two. In the crystal structure, Zeng discovered that the gold core is in the shape of an icosahedron. At the interface between the core and the surface-protecting molecules is a layer of sulfur atoms that bind with the gold atoms. The sulfur-gold-sulfur combinations stack into ladder-like helical structures. Finally, attached to the sulfur molecules is an outer layer of surface-protecting molecules whose carbon tails self-assemble into fourfold swirls.

“The helical features remind us of a DNA double helix and the rotating arrangement of the carbon tails is reminiscent of the way our galaxy is arranged. It’s really amazing,” Jin said.

These particular patterns are responsible for the high stability of Au133 compared to other sizes of gold nanoparticles. The researchers also tested the optical and electronic properties of Au133 and found that these gold nanoparticles are not metallic. [emphasis mine] Normally, gold is one of the best conductors of electrical current, but the size of Au133 is so small that the particle hasn’t yet become metallic. Jin’s group is currently testing the nanoparticles for use as catalysts, substances that can increase the rate of a chemical reaction.

*ETA April 14, 2015 at 9015 PDT: Coincidentally, researchers in Finland have been examining gold nanoparticles and the size at which they are considered metals and at which they are considered molecules (mentioned in my April 14, 2015 posting [Gold atoms: sometimes they’re a metal and sometimes they’re a molecule]).*

Getting back to patterns, the researchers have provided an A-ray image of Au133,

Caption: The X-ray crystallographic structure of the gold nanoparticle is shown. Gold atoms = magenta; sulfur atoms = yellow; carbon atoms = gray; hydrogen atoms = white. Credit: Carnegie Mellon


Caption: The X-ray crystallographic structure of the gold nanoparticle is shown. Gold atoms = magenta; sulfur atoms = yellow; carbon atoms = gray; hydrogen atoms = white.
Credit: Carnegie Mellon

Here’s a link to and citation for the paper,

Structural patterns at all scales in a nonmetallic chiral Au133(SR)52 nanoparticle* by Chenjie Zeng, Yuxiang Chen, Kristin Kirschbaum, Kannatassen Appavoo, Matthew Y. Sfeir, Rongchao Jin. Science Advances 20 Mar 2015: Vol. 1 no. 2 e1500045 DOI: 10.1126/sciadv.1500045

This paper appears to be open access.

* Link updated June 26, 2015.