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A French scientists claims there’s another portrait etched beneath the Mona Lisa — one of the most famous paintings in the world.


Pascal Cotte was first allowed by the Louvre Museum to analyze the painting in 2004, since he convinced them that the work of art won’t be damaged or altered in any way. The technology he used, called Layer Amplification Method (LAM), is very new in the field. The device fires intense beams of photons, then a camera records the reflections of these beams that can permeate though the surface. Based on these measurements, Cotte was able to reconstruct how the various layers underneath the apparent surface of the painting looked like, as if da Vinci were there painting La Joconde again. “We can now analyse exactly what is happening inside the layers of the paint and we can peel like an onion all the layers of the painting. We can reconstruct all the chronology of the creation of the painting,” Cotte told the BBC.

Apparently, one onion peel suggests there’s a different portrayal of Mona Lisa  — different from the way we’ve come to know her, at least (though debatable, historians attribute her identity to Lisa Gherardini, the wife of a Florentine silk merchant). The analysis shows that there was no smile, the gaze is totally different, as was the outfit. These features were then painted over.

Mr. Cote, next to a digital reconstruction (left) of the different Mona Lisa portrait he found. Image: Brinkworth Films
Mr. Cote, next to a digital reconstruction (left) of the different Mona Lisa portrait he found. Image: Brinkworth Films

Interestingly enough, Cotte has this theory which says that this earlier rendition was in fact the original Mona Lisa, a different person from the one we know today.

“The results shatter many myths and alter our vision of Leonardo’s masterpiece forever.

“When I finished the reconstruction of Lisa Gherardini, I was in front of the portrait and she is totally different to Mona Lisa today. This is not the same woman.”

If that’s true … well, I guess the Louvre can just throw away the museum label for the painting. Martin Kemp, Emeritus Professor of the History of Art at the University of Oxford, isn’t that convinced. Instead, what we’re seeing, Kemp suggests, are simply the various stages a painting goes through until it reaches the artist’s last brush stroke.

“I do not think there are these discreet stages which represent different portraits. I see it as more or less a continuous process of evolution. I am absolutely convinced that the Mona Lisa is Lisa,” he told BBC News.

Cotte’s findings and other insights can be learned in the upcoming BBC 2 documentary, The Secrets of the Mona Lisa. It airs on BBC Two at 21:00 GMT on 9 December.


When in 2007 Congress decided to extend the period daylight saving time, known as DST for short, by four weeks each year — three weeks in spring and one in fall — MIT researchers saw an opportunity:

“This [increase] produced a useful natural experiment for our paper which helped us isolate the effect of daylight from other seasonal factors that might affect crime,” authors Jennifer Doleac and Nicholas Sanders write.

Image via Wikipedia

It probably doesn’t come as a surprise to anyone that criminals thrive in the dark, and now we know by exactly how much: when DST comes into effect in spring, researchers identified a 7% decrease from average in daily number of reported robberies, and a whopping 27% decrease during the now-brighter evening hour. They also found strong evidence of a decrease in the incidence of rape in the evening hours.

And, according to the paper, thos decrease during evening hours isn’t accompanied by an increase in the morning.

But wait…DST shifts an hour of darkness from sundown to sunrise so, how can there be a decrease in overall daily crime? It’s dark for just as long each day, only at different hours, it doesn’t make sense!

It turns out it’s laughably simple — criminals just aren’t morning people.

“Most street crime occurs in the evening around common commuting hours of 5 to 8 PM,” the authors write, “and more ambient light during typical high-crime hours makes it easier for victims and passers-by to see potential threats and later identify wrongdoers.”

And as every crime carries a social cost — pain, suffering and lingering trauma, but also including monetary losses suffered by the victim, medical costs and lost earnings for the victim, police funding, legal services and incarceration costs for the government — the team wanted to see how many pennies we can save if we extend the period when DST is in effect.

Previous studies have estimated the total social cost of a single robbery at somewhere around $42,000, and that of rape at $240,000.  When you add it all up, a three-week increase in DST in the spring of 2007 saved the country some $246 million, the authors estimate.

“Assuming a linear effect in other months, the implied social savings from a permanent, year-long change in ambient light would be almost 20 times higher,” they conclude — several billion dollars annually.

They do caution, however, that this is just an assumption and that more research would be needed to determine whether the drop in crime from enacting permanent DST would hold true year-round.

Their work only adds weight behind the push to permanently extend DST year-round, a tiny change that has the potential to save hundreds of lives just from traffic accidents alone, and reduce work injuries and cases of heart attack. On the flipside, it could negatively affect certain crops and the farmers that grow them, and there are concerns about leaving schoolkids waiting for buses in the dark hours of the morning (though maybe we could change that too).

The non-biting blowfly Chrysomya megacephala is a common sight on dead bodies and forensic investigators use them to determine the time of death, referred to as the post mortem interval. A report from Tamil Nadu analyzed morphological features and molecular characterization through generation of DNA barcoding of the synanthropic (being ecologically associated with humans) derived form of C. megacephala for the first time. Their findings are significant in forensic sciences and were published in the open access Biodiversity Data Journal.

This image shows the larva and pupa of Chrysomya megacephala.
Image via sciencedaily

Chrysomya megacephala is a tremendously abundant species and is used as fish bait in northern and south-west India. It is known to breed in human faeces, decomposed meat and fish as well as in discarded organic materials, and thrives on corpses in many parts of the world. This fly therefore serves as a potential vector of many diseases due to its close association with human dwellings and is considered important in medical, veterinary and forensic sciences.

Post mortem interval (PMI) determination is useful in cases of homicide, suicide and accidental or unattended death because of natural causes. An important aspect of calculating the PMI is the accurate and quick identification of the dipteran fly collected from a crime scene.

When determining PMI, behavior and developmental times of the specie is essential. The most common way currently used to identify dipteran flies is to study the adult stage under a compound microscope. This requires that the larvae collected at the scene be reared to maturity. The fly can be identified in its young, larval form but if the critical characteristics are small or vary ever so slightly, misidentification is possible.

However, morphological identification of the fly can be difficult. But identifying them genetically, by encoding collected DNA sequences of mitochondrial cytochrome oxidase gene subunit I (mtCOI), is a much more precise method. Three forms of C. megacephala are recognized presently, those being the normal form (nf), the synanthropic derived form (sdf) and the recently reported feral derived form (fdf).

Nf is confined to forests of South Pacific Islands while the sdf form has spread around the world from Papua New Guinea. Fdf, found in the forests of the Himalaya, India is morphologically intermediate between normal and synanthropic derived forms. However, the occurrence of the synanthropic derived form of C. megacephala has not been documented in the State of Tamil Nadu, India.

In this context, a report for the first time for C. megacephala (sdf) from Royapuram fishing harbour, Chennai, Tamil Nadu, South East India is significant. A colony of C. megacephala was established from numerous second and third instar larvae collected from decaying fishes. The life expectancy of this fly is 40-45 days. Freshly emerged adults from pupae were identified through morphological and molecular studies.

A study pegged by the Ponemon Institute found cybercrime costs have gone up significantly relative to last year. According to the report, the average US company  loses $1.9 million to cyberattacks each year, up from $1.5 million reported last year. The bigger the company, the higher the costs. The same study found the average large US company loses  $15.4 million, which  is 19 percent higher from $12.7 million a year ago.

Criminals are stepping up their game and data breaches are becoming both common and devastating. In 2013, there were more than 100 DDOS attacks at over 100Gbps or higher , while events topping 20Gbps in the first half of 2014 nearly doubled those for the entire year of 2013. Yes, companies have also grown more sophisticated, but so far cyberattackers seem to be leading the arm’s race.


Some of the most famous recent hacks include Ebay (hackers had managed to steal personal records of 233 million users) , P.F. Chang (the company’s customer payment information records were breached, so thousands and thousands of credit cards surfaced on the black market) or Domino’s Pizza (Hacking group Rex Mundi held Domino’s Pizza to ransom over 600,000 Belgian and French customer records). All in all, today company lose  82 percent more money to cyber crime than they had six years ago, according to Ponemon.

“As an industry we’re getting better, but attacks are becoming much more invasive and sophisticated,” said Andrzej Kawalec, chief technology officer for Hewlett-Packard Co.’s HP Enterprise Security, which sponsored the study and sells cybersecurity services to businesses.

To assess costs, the Ponemon researchers factored in costs or damages incurred from detection, recovery, investigation and incident-response management. Expenses meant to cover loss of additional business due to security breaches were also included.

This was a global study  that spanned 252 companies in the U.S., United Kingdom, Germany, Australia, Japan, Russia and Brazil. Globally, the average annualized cost of cybercrime increased 1.9 percent from last year to $7.7 million.

After the flames from California’s forest fires died down, authorities brought in cadaver dogs to sniff through the charred remains of homes, woodland and the animals that perished in the fires, in their search for human victims. But how exactly can a hound discern between the smell of a deer carcass and that of a human remains? Researchers asked themselves the same question, and the results of their work reveal exactly how: Decomposing human bodies release a unique chemical cocktail, and experts hope the breakthrough can be useful to improve cadaver dog training or leaqd to the developmen of machines that could allow them to sniff out bodies faster than ever before.

Image via cliparsheep
Image via cliparsheep

“The smell of death” has been puzzling researchers for more than a decade. Two papers sparked the scientific community’s efforts in 2004 — one from a research station in Tennessee titled “Body farm” that analyzed the gases released during the latter stages of decomposition, the other from Greece, that focused on the early stages of the macabre process.

The preliminary list of carbon-based compounds given off during decay that these papers put together has been added on extensively since then. However, there have been conflicting reports about which ones are emitted only by humans. And so, in 2010 the Belgian Disaster Victim Identification Team asked analytical chemist Eva Cuypers and her forensic toxicology lab at the University of Leuven in Belgium for to find the best way to train cadaver dogs to pick out human scents.

Cuypers’s graduate student Elien Rosier started by putting tissue samples and organs from six autopsied corpses in jars in a lab closet. The jars were closed using screw caps which let in some air. They had stoppered holes that allowed the team to periodically take samples of the gas build-up inside.

Other jars were set up with pig, mouse, mole, rabbit, turtle, frog, sturgeon and bird remains. Pig remains in particular have often been used in past decomposition studies because of their rare similarity to human bodies: They have the same microbes in their guts, the same percentage of body fat, and similar hair as people. But it was not clear whether the decomposition process was the same because the two species had never been studied under identical conditions.

Rosier sampled the gases released by all the jars, and compared them by species. It took a long 6 months of work, during which she identified 452 compounds that make up the rotting smell of cadavers. Her first try was with compounds containing sulfur, as they seemed to differentiate between the samples. They weren’t unique to humans however, or even present in all humans — and they weren’t very stable chemically, disappearing over time; so she looked to esters.

Esters are chemical compounds that are crucial in the formation of animal fats. She found that eight compounds distinguished pig and human remains from those of other animals, and five esters separated pigs from humans, PLOS ONE reports:

“The mixture of [these] compounds might be used in the future to more specifically train cadaver dogs,” Cuypers says.

“So far there [hasn’t been] any study based on monitoring human and pig carcasses under exactly the same conditions,” says Agapios Agapiou, an analytical chemist at the University of Cyprus in Nicosia who was not involved with the work. “But there are still many steps before creating a synthetic substance to train cadaver dogs.”

John Sagebiel, an analytical chemist at the University of Nevada, Reno, who was also uninvolved in the study. says relying solely on analytical chemistry to determine what cadaver dogs are sniffing out is too limited. It would be better to work with the dogs themselves to figure that out, he adds.

“I don’t think there’s one specific thing that says it’s human,” he says.

Arpad Vass — who is associated with the University of Tennessee, Knoxville, Body Farm and has compiled a list of compounds released by decomposing humans — points out that the use of specific tissues, as opposed to a whole body, and their isolation in jars means the researchers are looking at just a subset of the bacteria and other environmental factors that influence decomposition.

Cuypers says her team plans to address some of these shortfalls in future studies.

“The next step in our research is to see whether the same compounds are found in buried, full decomposing bodies in the field and to see whether dogs trained on the mixture respond more specific[ally] to human decomposing bodies.” If this cocktail passes muster, the find could pave the way for developing an electronic nose that can do what dogs do, she adds.

A novel technique shown by researchers in Belgium can estimate the age of a criminal, or victim for that matter, by interpreting genetic code found in blood or tooth samples. Of course, there are many methods employed by forensic scientists that are used to estimate age, but sometimes victims might be so torn up (burned, severed limbs, etc.) that there’s no other way to estimate the age. Likewise, if the only lead a crime scene investigator has is a blood stain left over by the criminal or possibly some other DNA containing sample, then this is the only chance they have of at least profiling the age. Sometimes, this can make all the difference in the world since it narrows the search and makes police work a lot more bearable.

TDL Genetics
TDL Genetics

The DNA and genetic material is not fixed, but always changing. Depending on our environment some genes might be turned on or off, and these changes in the genome can even be passed on to offsprings. The study of live DNA changes is called epigenetics. Likewise, the genome changes as we age. All our organs, for instance, are regulated by the genome so you can tell how old a person is by identifying which key genes are switched on or off, say researchers at Belgium’s University of Leuven (KU Leuven).

“The behaviour of our organs and tissues depends on which of our genes are activated,” Bram Bekaert, a forensic scientist at KU Leuven, explained in a press release. “As we grow older, some genes are switched on, while others are switched off. This process is partly regulated by methylation, whereby methyl groups are added to our DNA. In specific locations, genes with high methylation levels are deactivated.”

For now, the researchers tested this hypothesis using only four DNA methylation markers. Even so, they were able to accurately assess a person’s age using blood and tooth samples with a margin of error of 3.75 years and 4.86 years, respectively.

The findings appeared in the journal Epigenetics.

People suffering from a severe mental disorder that commit crime and are incarcerated have different characteristics than those who are hospitalized rather than incarcerated after an offence.

The full study of the new study  by researchers at the Institut universitaire en santé mentale de Montréal (IUSMM) and the Institut Philippe-Pinel de Montréal (IPPM), affiliated with the University of Montreal, can be found here.

Image via memegenerator
Image via memegenerator

The study looked at persons suffering from severe mental disorders — such as schizophrenia — with a criminal record, and divided them into two groups: those that were incarcerated, and the others that were hospitalized in a forensic psychiatry unit and received medical care.

“We found a clear difference between people with a mental illness who are incarcerated for a crime and those declared not criminally responsible for a crime and then hospitalized at a psychiatric institution,” explained Dr. Alexandre Dumais, a researcher at the IPPM and the IUSMM and the study’s first author.


“Since the adoption of Bill C-30 in 1992, federal detention centres have had a significant decrease in the number of people with severe mental disorders, such as schizophrenia. Conversely, there has been an increase in the number of people declared not criminally responsible on account of mental disorder (NCRMD) and who find themselves in the psychiatric network,” added Dr. Dumais, who is also an assistant clinical professor in the University of Montreal’s Faculty of Medicine and a psychiatrist at the IPPM.

Conducted in collaboration with the Centre d’études sur les mesures de contrôle en santé mentale of the IUSMM, this research compared the characteristics of individuals who suffer from serious mental disorders and who were either incarcerated (I = 44) or declared NCRMD and hospitalized in a forensic psychiatry care unit (H = 59) after committing a crime. The researchers analyzed data from an extensive research program that explored the clinical and sociodemographic profiles of men who suffer from severe mental disorders. The researchers found differences between people who are incarcerated and those declared NCRMD and who are hospitalized.

  • Higher level of schooling among those declared NCRMD (equivalent of Secondary 5)
    25% for people who are incarcerated versus 54% for those declared NCRMD
  • Greater use of specialized mental health services among those declared NCRMD
    40% for people who are incarcerated versus 73% for those declared NCRMD
  • Greater history of suicide attempts among people who are incarcerated
    66% for people who are incarcerated versus 34% for those declared NCRMD
  • Greater history of criminal activity with or without violence among people who are incarcerated
    71-80% for people who are incarcerated versus 25-29% for those declared NCRMD
  • More concomitant drug or alcohol disorders and a higher level of psychopathy among incarcerated people

“This study confirms the work of my colleagues at the IPPM: incarcerated people with a severe mental disorder have particular characteristics, along with criminal behaviour and psychopathic traits,” stated Jean-François Pelletier, a researcher at the IUSMM and an assistant professor at the University of Montreal’s Faculty of Medicine.

“People who are declared NCRMD and hospitalized use mental health services more, and they are often under psychiatric care before they commit the offence,” explained Mr. Pelletier.

“The characteristics of incarcerated people put them on a path to criminal behaviour and prevent them from getting the psychiatric care they need,” stated Dr. Dumais. “People who commit an offence need to serve their time, but they also need care if they suffer from an illness. New shared care models between the legal and health care systems need to be implemented so that these patients can get better treatment and so that we can reduce their risk of violent and antisocial behaviour. Some countries have launched initiatives in this area, but these programs haven’t been formally tested with rigorous research methods. Further studies should look at these models to determine which are ones are effective.”

An increasing volume of attacks using file-less malware and other anti-forensic measures is leading a greater-than-ever skill gap in the cybersecurity bizz. These tehniques leave little to no trace on physical disks, and unfortunately the good guys aren’t keeping up: There’s a shortage of skilled digital forensics practitioners who are able to efficiently investigate these types of offensives.

Image via welnet-tech

“Attackers know how forensics investigators work and they are becoming increasingly more sophisticated at using methods that leave few traces behind—we are in an arms race where the key difference is training,” says Alissa Torres, founder of Sibertor Forensics and former member of the Mandiant Computer Incident Response Team (MCIRT).

Torres reports that in the last year, there has been a rise in file-less malware, programs that avoid installation on the target’s file system and operates only in it’s volatile memory.

“Five years ago, to see sophisticated anti-analysis and acquisition techniques in the wild was like seeing a unicorn but that is no longer the case,” she said. “As techniques for detecting trace artefacts on a compromised system have improved, the more sophisticated attackers have adapted quickly.”

The SANS Institute estimates that possibly one in four digital forensics and incident response (DFIR) professionals has the level of training to successfully analyze the new types of self-defense techniques that include more sophisticated rootkit and anti-memory analysis mechanisms.

“The memory forensics field exploded around 2005 when a lot of the parsing tools started to become available and its use in forensics has been growing ever since,” explained Torres. “An incredible advantage this analysis method has is speed—a skilled expert in memory forensics can discover insights a lot quicker and pick up on information that is missed in traditional disk imaging.”

Although the tools at our disposal have improved, Torres pointed out that  “owning a hammer and saw doesn’t make you a carpenter—a deeper understanding of the operating system internals to include memory management allows the examiner to access target data specific to the needs of the case at hand.”



Face matching is, simply put, the practice of asserting if a face in a number of different pictures belongs to the same individual. And while many software companies and technology giants have invested heavily in such software (Hulu’ss facial recognition software, for example, or Facebook’s newly unveiled facial matching one), it is encouraging to see that the best of the best at it are the ones that try to protect us from those that go staby-stab in the night: forensic experts.

The first study to test the skills of FBI agents and other law enforcers who have been trained in facial recognition has provided a reassuring result – they perform better than the average person or even computers on this difficult task. The team working on the data included colleagues at the National Institute of Standards and Technology and the University of Texas at Dallas in the US, and their findings were published the Proceedings of the Royal Society B.

Image via theguardian
Image via theguardian

For the study, the researchers tested an international group of 27 facial forensic examiners with many years of experience who were attending a meeting of the Facial identification Scientific Work Group. The group’s member agencies include the FBI, police and customs and border protection services in the US, Australia and other countries.

The experts were given three tests where they had to decide if pairs of images were of the same person. Their performance was compared to that of a control group of non-experts who were attending the same meeting, as well as a group of untrained students. The pairs of images used were selected to be particularly challenging, reflected in the fact that computer algorithms were 100 percent wrong on one of the tests. Participants were given either two seconds, or a more generous 30 seconds to decide depending on the test.

“Overall, our study is good news. It provides the first evidence that these professional examiners are experts at their work. They were consistently more accurate on all tasks than the controls and the students,” says White.

The findings suggest that forensic examiners trained for this task identify individuals in a different way from those that just have a knack for it, those naturally very good at face matching, the so-called super-recognizers.

“Super-recognizers tested in previous studies appear to rely on automatic, holistic processes when they compare facial images, but forensic examiners use analytical methods,” says research leader UNSW psychologist Dr. David White.

“The examiners’ superiority was greatest when they had a longer time to study the images, and they were also more accurate than others at matching faces when the faces were shown upside down. This is consistent with them tuning into the finer details in an image, rather than relying on the whole face.”

With the rise of CCTV imagery and hand-held cameras on mobile phones comes a huge pool of information that forensic experts can use. The comparison of facial features to identify suspects has thus become a powerful, efficient and important source of evidence to clear a name or imprison a felon.

“These identifications affect the course and outcome of criminal investigations and convictions. But despite calls for research on any human error in forensic proceedings, the performance of the experts carrying out the face matching had not previously been examined,” says White.

“However, it is important to note that although the tests were challenging, the images were relatively good quality. Faces were captured on high-resolution cameras, in favorable lighting conditions and subjects were looking straight at the camera,” says White. “This is often not the case when images are extracted from surveillance footage,” he went on to add.

Research collaborators included Alice O’Toole, Matthew Hill and Amanda Hahn from the University of Texas at Dallas and Jonathon Phillips from the National Institute for Standards and technology in the US.



A new study from researchers at the Harvard School of Public Health shows that the microbial communities each of us carries on our skin or in our bodies can be used to uniquely identify individuals, much like a fingerprint. The team behind the study showed that personal microbiomes contain enough distinguishing features to identify a person over a long amount of time from a research study population of hundreds of people. It is the first published work that shows microbiome identification is feasible.

Taken together, DNA sequences from four microbial species distinguish the starred person's microbiome from the microbiomes of five other people Image via
Taken together, DNA sequences from four microbial species distinguish the starred person’s microbiome from those of five other people
Image via

“Linking a DNA sample to a database of DNA ‘fingerprints’ is the basis for forensic genetics, now a decades-old field.”

“We’ve shown that the same sort of linking is possible using DNA sequences from microbes inhabiting the human body — no human DNA required. This opens the door to connecting human microbiome samples between databases, which has the potential to expose sensitive subject information — for example, a sexually-transmitted infection, detectable from the microbiome sample itself,” said lead author Eric Franzosa, research fellow in the Department of Biostatistics at Harvard Chan.

More than just a gut feeling – it’s gut forensics

The team used publicly available microbiome data mined from the Human Microbiome Project (HMP), which surveyed microbe samples from stool, saliva, skin and other sites from up to 242 individuals over a month-long period. They adapted a computer algorithm to crunch the data and obtained combinations of stable and distinguishing sequence features from the initial samples that work as individual-specific “codes”.

When compared to microbiome samples collected at follow-up visits with the same individuals and to samples from independent groups of individuals, the codes were shown to be unique among hundreds of individuals. A large fraction of the microbial signature remained stable over a one-year sampling period, those obtained from gut samples in particular. Here, more than 80% of individuals could be identified without a trace of doubt for up to a year after the sampling period.

“Although the potential for any data privacy concerns from purely microbial DNA is very low, it’s important for researchers to know that such issues are theoretically possible,” said senior author Curtis Huttenhower, associate professor of computational biology and bioinformatics at Harvard Chan School. “Perhaps even more exciting are the implications of the study for microbial ecology, since it suggests our unique microbial residents are tuned to the environment of our body — our genetics, diet, and developmental history — in such a way that they stick with us and help to fend off less-friendly microbial invaders over time.”



Whether it's cybercrimes, psychological profiling, or simply data analysis, artificial intelligence is starting to play a more and more important role in forensics and...