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Microbiomes could be the new fingerprints

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 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.”


Caltech works on the next generation of data-security programes

The technology industry and academia have always been closely knit together, working to engage today’s brains into being tomorrow’s professionals, to ensure students are learning essential skills and cultivate talent. And in today’s world, industry and businesses have come to rely on the bright minds to address emerging cyber threats.

Image via datumbox

Guidance Software, a software company headquartered in Pasadena, has funded a program at the California Institute of Technology (Caltech) to support data security research using advanced anomaly science. Discoveries will be published and used to enhance data breach detection and incident response capabilities.

“Hackers are relentless. Breaches of major corporate or government data centers are on the rise to the tune of billions of dollars in losses per year,” said Michael Harris, CMO of Guidance Software. “Our industry is facing a massive labor shortage of cybersecurity specialists. To address this shortfall, we are working with data scientists at Caltech, one of the most respected research universities in the world, to use anomaly detection, complex event processing, and machine learning to help us thwart these breaches and reduce the damage to taxpayers and corporate profits.”

The program can rely upon some of the best brains in the biz, being run out of Caltech’s new lab, the , in collaboration with NASA Jet Propulsion Laboratory (JPL). Principal scientist Julian Bunn will be heading the research and professor emeritus Mani Chandy. The pair has developed algorithms and processes to detect anomalous patterns in data sets used in critical areas such as earthquake prediction and now in the detection of advanced malware and their polymorphic variants.

Timely and effective breach detection of modern threats requires a different approach that that most defensive software employs. Traditional approaches deal with data security issues through the use of signatures, blacklists or shared threat intelligence. They however leave systems vulnerable to unknown of zero-day malware. Based on machine learning and statistical models, a software that relies on anomaly detection can find such infiltrations by focusing on detection of anomalous or atypical behavior that may indicate unauthorized access to sensitive data.

“We are thrilled to be working with Guidance Software on such an important initiative,” said Karina Edmonds, executive director for corporate sponsorships at . “Our institute is focused on applying science to expand human knowledge and benefit society through research. This work to solve for breach detection and malware discovery is consistent with our mission.”


FBI hair-matching gave fautly evidence for decades, but the cases are being reviewed.

What juror won’t take the word of a federal agent, and who in the jury box won’t be swayed by evidence found, analyzed and presented by a federal agent? It’s all in the title. “They know what they’re doing, so if they bring evidence to the courtroom it’s bound to be fail proof, right?” asks the idealistic, stars-and-stripes juror. Well, it seems that no, FBI agents are just as human as the rest of us.

A strand of human hair under the microscope. Image via wrongfulconvictionsblog A strand of human hair under the microscope.
Image via wrongfulconvictionsblog

To err is human, to overstate is just convenient

Hair matching has long been used by the FBI as a means to incriminate or exonerate a suspect of a crime. But the FBI’s hair-comparison unit actually gave unscientific testimony against criminal defendants for more than 20 years before 2000, according to the FBI and the Justice Dept. Among the FBI’s 28 microscopic hair experts, 26 “overstated forensic matches” to favor the prosecution in nearly all of the 268 cases reviewed so far, the reports.

“The FBI’s three-decade use of microscopic hair analysis to incriminate defendants was a complete disaster,” says Peter Neufeld, who helped found the Innocence Project.

The cases reviewed include 32 defendants given the death sentence, of which 14 have already died in prison or were executed. About 2,500 cases where hair-matching was used to incriminate are being looked at in total.

Even if other evidence may have sufficed to convict those founds guilty in the cases, the FBI acknowledged the problem (hats off to them for manning up and admitting their mistake, at last) and agreed to work with the National Association of Criminal Defense Lawyers (NACDL) and the Innocence Project in reviewing cases between 1972 and 1999.

Courts in 46 states and the District of Columbia are receiving information that can lead to appeals if defense lawyers, prosecutors or judges will be able, and willing.

The process of hair matching has been used by the FBI to obtain evidence for nearly three decades now.
Image via arstehnica

The Post reports that there isn’t any scientific standard for matching hair. Worse, the forensic-hair scandal is only part of an ongoing review of all criminal forensics, which the Post has reported on , , and .

“The forensic science system … has serious problems that can only be addressed by a national commitment to overhaul the current structure,” a science panel concluded back in 2009.


Weak Link Between Psychosis and Violence, Study Finds

It’s common held belief that violent criminals often suffer from a long history of mental illness that drives their destructive or murderous behavior. But new research published Clinical Psychological Science by APS fellow Jennifer Skeem and colleagues form University of California says the link between mental illness and violence isn’t so strong as we thought.

Image via medicaldaily

To investigate the relationship between psychosis – that they defined as a severe mental disorder accompanied by delusions and hallucinations – and acts of violence, the team mined data from the . This gave them information on over 1,ooo violent offenders, who were interviewed every 10 weeks for a year after their release from incarceration.

The aim of the MacArthur study was to examine if participants committed any violent acts (for example physical injury, sexual assaults or use of a weapon) and whether the acts were preceded by psychotic events. The study also included data on the participants’ other personality traits or disorders, cognitive abilities and problematic behaviors.

“The Scream” is considered an illustrative work of art for feelings of anxiety and is associated with psychotic events.
Image via lookfordiagnosis

The team’s results showed what experts have been saying for years – most violent crimes can be traced back to a small group of repeat offenders. About 10% of individuals were responsible for 50% of the violent incidents that occurred in the year after their release. Out of these, about half reported symptoms of psychosis such as delusions or hallucinations at one point during their interviews. However, only 12% of incidents were preceded by symptoms consistent with psychosis, suggesting that the link between the two was rather weak.

But Skeem and his colleagues wanted to know whether some individuals routinely experienced psychosis before each violent act, if they acted as the trigger for the incidents, however infrequent the instances of psychosis-preceded violence proved to be.

Using multilevel modeling, they determined that there were mainly two types of repeat violent offenders: those that at no point experienced psychotic events before violence (80% of the sample) and those that only occasionally experienced psychosis before violence (15%).

The popular conception of violent criminals, driven to kill by a psychotic event is thus actually pretty rare, characteristic to only 1 in 20 of repeat offenders.

“There is little evidence for a subgroup with exclusively psychosis-preceded violence,” the study concludes.

The findings also shed some light on the inner workings of individuals who sometimes experience psychosis prior to committing violent acts and those who never did so. Those with occasional psychosis were more likely to also show bipolar disorders, schizophrenia, and other mental disorders. Those who never displayed psychosis prior to violence tended to score lower on verbal intelligence and showed greater antisocial tendencies. These patterns were subtle, however, and the authors suggest that they provide interesting avenues for further research.

Skeem and colleagues conclude that although symptoms of psychosis should be tracked and evaluated in violent offenders, prescribing different treatments to different types of offenders based on diagnoses of psychosis may not be the best use of resources.

“Effective treatment of psychosis will have negligible direct effects on violence for most patients and important but partial effects for the remainder,” the researchers write.

Instead, the authors recommend that “programming for individuals with repeated violence may need to encompass factors associated with social deviance, whether patients occasionally engage in acts of violence related to psychosis or not.”

In other words, providing anger management treatment to all repeat violent offenders may be more effective at reducing violent crime than offering specialized treatment to those who experience psychosis.

To read more of the researchers’ work exploring links between mental illness, personality, and crime, check out , , and .

Let bring some heat back to cold cases

A brand new forum named Cold Case Collective debuted a few days back, set up for those that would like to turn their hand at working in investigations, or those that already are but have that one cold case still bugging them.

Image via Idolbin


The forum gives you a place to share data, facts and theories with others, to put your brain to work on solving a case or get a fresh perspective on your work.

It’s a really powerful resource. People working on a missing person’s case are encouraged to post their findings in the MP section, by name or state, so that people may pitch in with information or theories. The Forensics section may help with linking two pieces of information, or matching evidence to the case.

If you are not sure what cold case to begin working on, you may like to start working on either a john or jane doe or a case that has gone cold in your own home town. Go to  and start looking around or ask Google for “cold cases” in your area and find something that piques your interest.

Or just visit the General Discussions board and get a feel of the community before you dip into the forum.

The more people join, the more information will be available for sharing, more eyes be put to good use and theories will become wilder, and probably more true. So why not become a consulting investigator?

You can visit the forum at .


Stone Age massacre, torture and mass graves: the Schoeneck-Kilianstaedten site

A Stone Age site near Frankfurt, Germany, shows evidence of a “final lethal crisis of the first Central European farmers of the Early Neolithic Linearbandkeramik Culture”, says .

The 7,000 year old conflict left a chilling legacy: the mass graves of 26 Linearbandkeramik  (LBK) victims, with smashed skulls, arrow wounds and even smashed shin bones.

Settling in small villages in the central part of Europe around 5500 B.C, the LKB people (named so after the German name of their style of pottery) lived for the most part along the waterways of the continent. They lived in large longhouses and farmed wheat, peas and barley, also turning their hand to raising cattle. Their craftsmen made excellent stone tools and traded in obsidian.

They were a prosperous people, and as it usually happens other, less well-to-do neighbors wanted in on a slice of their pie.

The pebbles really bring out the flavor.
Image via centenarylandscaping

A growing body of evidence shows that the last phase of their settlement in the region was marked with “unequivocal lethal violence on a large scale.”

Two other sites, Talheim, Germany and Aspam/Schletz in Austria show mass graves that date from around the same time and show fatal violence. But the site at Schoeneck-Kilianstaedten stands out amongst the others due to the brutality of the victim’s treatment, say researchers from the University of Mainz and the University of Basel.

Such shin fractures were found at the site.
Image credits PNAS University of Basel

The skeletons found were almost all male, but also included children.

“Although the absence and possible abduction of younger females has been suggested for other sites previously, a new violence-related pattern was identified here: the intentional and systematic breaking of lower limbs,” the team found. “The abundance of the identified perimortem fractures clearly indicates torture and/or mutilation of the victims.”

One of the most disturbing finds are the injuries on the bodies. Several researchers have maintained that the wounds ,Including smashed teeth and broken lower limbs, were inflicted after death as part of ritualistic behavior. But the new findings contend that the perimortem injuries were clearly intended to be parts of torture or mutilation.

The LBK people, who spread westward along the Danube into the continent, began to disappear from the archaeological record after about 600 years – in 4900 B.C., according to archeological accounts.



More guns mean more officers in the morgue

A new study comes to buckle the widely-held belief that cities with high rate of crime translate directly to higher numbers of police fatalities.

The findings, published in the American Journal of Public Health shows that states with more guns also have the highest rates of police officers killed in the line of duty.

The UIC study found that police officers in states with high private gun ownership are more than three times more likely to be killed on the job than in states with the lowest gun ownership.
Image credits: Megan Strand/UIC

When data from cities such as Camden and Newark, New Jersey,  is compared to numbers from the state of Montana, something interesting comes up. While the two cities are known for their more violent nature, they have relatively-low rates of homicide amongst police officers, and the Big Sky Country has some of the greatest per-capita dangers to law enforcement, according to David Swedler, research assistant professor of environmental and occupational health sciences in the University of Illinois at Chicago School of Public Health.

It all boils down to guns, and places where private ownership of guns means occupation hazards for officers, Swedler went on to explain.

“If we’re interested in protecting police officers, we need to look at what’s killing them, and what’s killing them is guns,” he said. “We know that 92 percent of police officers killed in the line of duty are killed by guns, three-quarters of which are handguns.”

The scientists looked at all killings of police officers from 1996 to 2010. Of the 782 homicides of police over the period, 716 were committed using guns, and 515 with handguns, they found.

A correlation between more gun ownership and higher incidence of cops killed existed. And it all makes sense. Officers are surprisingly resistant to frying pans or nerf guns I’ve been told.

But somehow they just can’t handle flying bullets. Who would have thought?
Image via hdwallpaperscool

And the correlation stands across America. Alabama, Alaska, Arkansas, Mississippi, and Montana were all in the top quintile for gun ownership and law-enforcement homicides. Connecticut, Massachusetts, New Jersey, New York and Rhode Island were at the opposite end, in the lowest quintile for guns and cop homicides.

“We found that officers aren’t being killed in stats with high violent-crime rates. While violent crime rates didn’t track closely to officer homicide rates, it was public gun ownership that had the strongest relationship,” Swedler added.

Rates of gun ownership studied ranged from 4.8 percent of households in Washington D.C., to 62 percent in Wyoming. Overall, 38 percent of U.S. households have at least one gun.

So, who wants to become a policeman?

Forensic teams scour rhino killing scenes in Kruger park

Rhino horn powder is a desperately sought after ingredient for traditional medicine in countries such as Vietnam. And the only thing barring the way to traditional health in such places is just a bit of legislation – rhinos are endangered, and killing them is illegal. But sadly (or gladly, depending who you ask) there are always those willing to kill for enough money, poachers, and there’s a lot of them.

Government data paints a grim picture. 1,215 animals were killed in South Africa last year, a triple of the 448 recorded in 2011. Out of these, 827 victims were took down out of Kurger Park’s population of 9000 animals.

Hey dude, pull my horn.
Image via

Confronted with the surge in poaching incidents, Kruger national park has the keepers on high alert, and rhino killings are treated like a crime scene and scoured by forensic experts.

The last victim in the Kruger National Park’s poaching business is a black rhino, killed under the light of the fool moon. The shot alerted park keepers that rushed to the scene and in the ensuing firefight, shot and killed one of the poachers while his accomplice ran away.

Four days later, investigators – with a group of journalists in tow – arrived to collect DNA and other evidence to help trace the weapon and prove the origin of the horn sawn off for sale overseas. The scene that media were invited to this month was a few hundred meters off a dirt road in the bush, and not far from a perimeter fence – a poaching “hot spot”.

A game ranger stands guard as police investigate the scene around the carcass of a black rhinoceros that had been shot by poachers in the Kruger National Park, in this picture taken August 4, 2015.
Image via yahoo

Most poachers come from neighboring Mozambique, the world’s poorest country, sharing a 350 km (210 mile) wide border with Kruger, and from the small villages that surround the Park. The largest part of killings take place in the marginal areas of the park, and it makes sense – given the economic hardships of life around Kruger.

The forensic work was undertaken by police surgeon Silence Mdluli, who wore a face mask and was clad in blue surgical overalls, and investigator Bella Khosa.

The rotting corpse lay sprawled on its left side, its ribs picked clean by scavengers. The horn had been hacked off.

The forensic team’s work included taking tissue samples and cutting away a toenail for DNA analysis.

“If we recover the horn, this can be matched to the DNA,” Khosa explained.

The corpse was marked as exhibit A, while a pair of shell casings found about 10 m away were marked as exhibits “2” and “3”. They have been discharged from a .458 caliber rile – basically, an elephant gun. If it is ever retrieved, the shells could be matched to it. A metal detector was also used to locate any bullets still lodged in the corpse, but none were found. Given the high powered weapon use and the size of the animal (Black rhinos are the rarer and smaller of Africa’s two species – the other being the white rhino ) of around 200 kg (440 lb), investigators believe the slugs went right through it.

Mdluli also tied a plastic ribbon to the branch of a tree. “If a chopper sees the carcass, this will tell them it is a known crime scene,” he said.

Such investigations, combined with red-handed arrests made by rangers, are starting to yield results. In Mpumalanga province which borders Kruger, the conviction rate in rhino cases is currently 100 percent.



Detecting Organic Constituents of Gunshot Residue

Analysis of Organic Gunshot Residue (OGSR for shot) may improve how reliable we can tell whether a suspect discharged his weapon or not, as this type if residue are less likely to be contaminated by the environment.

A new In Brief from NIJ’s Forensic Technology Center of Excellence takes a look as how ion spectrometry and mass spectometry can be used to detect OGSR materials. Portable x-ray fluorescence devices have promise as a rapid and efficient screening method for inorganic constituents.

The evaluation, conducted by West Virginia University, found that performance of any instrument was more likely to be affected by the hand swabbing technique used rather than instrument limitations. All three instruments showed promise for detecting OGSR, but significant work remains to fine tune these approaches.