New PCM could supply 36PB of memory to CPUs

Read an article this past week on how quantum geometry can enable a new form of PCM (phase change memory) that is based on stacks of metallic layers (SciTech Daily article: Berry curvature memory: quantum geometry enables information storage in metallic layers), That article referred to a Nature article (Berry curvature memory through electrically driven stacking transitions) behind a paywall but I found a pre-print of it, Berry curvature memory through electrically driven stacking transitions.

Figure 1| Signatures of two different electrically-driven phase transitions in WTe2. a, Side view (b–c plane) of unit cell showing possible stacking orders in WTe2 (monoclinic 1T’, polar orthorhombic Td,↑ or Td,↓) and schematics of their Berry curvature distributions in momentum space. The spontaneous polarization and the Berry curvature dipole are labelled as P and D, respectively. The yellow spheres refer to W atoms while the black spheres represent Te atoms. b, Schematic of dual-gate h-BN capped WTe2 evice. c, Electrical conductance G with rectangular-shape hysteresis (labeled as Type I) induced by external doping at 80 K. Pure doping was applied following Vt/dt = Vb/db under a scan sequence indicated by black arrows. d, Electrical conductance G with butterfly-shape switching (labeled as Type II) driven by electric field at 80 K. Pure E field was applied following -Vt/dt = Vb/db under a scan sequence indicated by black arrows. Positive E⊥ is defined along +c axis. Based on the distinct hysteresis observations in c and d, two different phase transitions can be induced by different gating configurations.

The number one challenge in IT today,is that data just keeps growing. 2+ Exabytes today and much more tomorrow.

All that information takes storage, bandwidth and ultimately some form of computation to take advantage of it. While computation, bandwidth, and storage density all keep going up, at some point the energy required to read, write, transmit and compute over all these Exabytes of data will become a significant burden to the world.

PCM and other forms of NVM such as Intel’s Optane PMEM, have brought a step change in how much data can be stored close to server CPUs today. And as, Optane PMEM doesn’t require refresh, it has also reduced the energy required to store and sustain that data over DRAM. I have no doubt that density, energy consumption and performance will continue to improve for these devices over the coming years, if not decades.

In the mean time, researchers are actively pursuing different classes of material that could replace or improve on PCM with even less power, better performance and higher densities. Berry Curvature Memory is the first I’ve seen that has several significant advantages over PCM today.

Berry Curvature Memory (BCM)

I spent some time trying to gain an understanding of Berry Curvatures.. As much as I can gather it’s a quantum-mechanical geometric effect that quantifies the topological characteristics of the entanglement of electrons in a crystal. Suffice it to say, it’s something that can be measured as a elecro-magnetic field that provides phase transitions (on-off) in a metallic crystal at the topological level. 

In the case of BCM, they used three to five atomically thin, mono-layers of  WTe2 (Tungsten Ditelluride), a Type II  Weyl semi-metal that exhibits super conductivity, high magneto-resistance, and the ability to alter interlayer sliding through the use of terahertz (Thz) radiation. 

It appears that by using BCM in a memory, 

Fig. 4| Layer-parity selective Berry curvature memory behavior in Td,↑ to Td,↓ stacking transition. a,
The nonlinear Hall effect measurement schematics. An applied current flow along the a axis results in the generation of nonlinear Hall voltage along the b axis, proportional to the Berry curvature dipole strength at the Fermi level. b, Quadratic amplitude of nonlinear transverse voltage at 2ω as a function of longitudinal current at ω. c, d, Electric field dependent longitudinal conductance (upper figure) and nonlinear Hall signal (lower figure) in trilayer WTe2 and four-layer WTe2 respectively. Though similar butterfly-shape hysteresis in longitudinal conductance are observed, the sign of the nonlinear Hall signal was observed to be reversed in the trilayer while maintaining unchanged in the four-layer crystal. Because the nonlinear Hall signal (V⊥,2ω / (V//,ω)2 ) is proportional to Berry curvature dipole strength, it indicates the flipping of Berry curvature dipole only occurs in trilayer. e, Schematics of layer-parity selective symmetry operations effectively transforming Td,↑ to Td,↓. The interlayer sliding transition between these two ferroelectric stackings is equivalent to an inversion operation in odd layer while a mirror operation respect to the ab plane in even layer. f, g, Calculated Berry curvature Ωc distribution in 2D Brillouin zone at the Fermi level for Td,↑ and Td,↓ in trilayer and four-layer WTe2. The symmetry operation analysis and first principle calculations confirm Berry curvature and its dipole sign reversal in trilayer while invariant in four-layer, leading to the observed layer-parity selective nonlinear Hall memory behavior.
  • To alter a memory cell takes “a few meV/unit cell, two orders of magnitude less than conventional bond rearrangement in phase change materials” (PCM). Which in laymen’s terms says it takes 100X less energy to change a bit than PCM.
  • To alter a memory cell it uses terahertz radiation (Thz) this uses pulses of light or other electromagnetic radiation whose wavelength is on the order of picoseconds or less to change a memory cell. This is 1000X faster than other PCM that exist today.
  • To construct a BCM memory cell takes between 13 and 16  atoms of W and Te2 constructed of 3 to 5 layers of atomically thin, WTe2 semi-metal.

While it’s hard to see in the figure above, the way this memory works is that the inner layer slides left to right with respect to the picture and it’s this realignment of atoms between the three or five layers that give rise to the changes in the Berry Curvature phase space or provide on-off switching.

To get from the lab to product is a long road but the fact that it has density, energy and speed advantages measured in multiple orders of magnitude certainly bode well for it’s potential to disrupt current PCM technologies.

Potential problems with BCM

Nonetheless, even though it exhibits superior performance characteritics with respect to PCM, there are a number of possible issues that could limit it’s use.

One concern (on my part) is that the inner-layer sliding may induce some sort of fatigue. Although, I’ve heard that mechanical fatigue at the atomic level is not nearly as much of a concern as one sees in (> atomic scale and) larger structures. I must assume this would induce some stress and as such, limit the (Write cycles) endurance of BCM.

Another possible concern is how to shrink size of the Thz radiation required to only write a small area of the material. Yes one memory cell can be measured bi the width of 3 atoms, but the next question is how far away do I need to place the next memory cell. The laser used in BCM focused down to ~1.5 μm. At this size it’s 1,000X bigger than the BCM memory cell width (~1.5 nm).

Yet another potential problem is that current BCM must be embedded in a continuous flow of liquid nitrogen (@80K). Unclear how much of a requirement this temperature is for BCM to function. But there are no computers nowadays that require this level of cooling.

Figure 3| Td,↑ to Td,↓ stacking transitions with preserved crystal orientation in Type II hysteresis. a,
in-situ SHG intensity evolution in Type II phase transition, driven by a pure E field sweep on a four-layer and a five-layer Td-WTe2 devices (indicated by the arrows). Both show butterfly-shape SHG intensity hysteresis responses as a signature of ferroelectric switching between upward and downward polarization phases. The intensity minima at turning points in four-layer and five-layer crystals show significant difference in magnitude, consistent with the layer dependent SHG contrast in 1T’ stacking. This suggests changes in stacking structures take place during the Type II phase transition, which may involve 1T’ stacking as the intermediate state. b, Raman spectra of both interlayer and intralayer vibrations of fully poled upward and downward polarization phases in the 5L sample, showing nearly identical characteristic phonons of polar Td crystals. c, SHG intensity of fully poled upward and downward polarization phases as a function of analyzer polarization angle, with fixed incident polarization along p direction (or b axis). Both the polarization patterns and lobe orientations of these two phases are almost the same and can be well fitted based on the second order susceptibility matrix of Pm space group (Supplementary Information Section I). These observations reveal the transition between Td,↑ and Td,↓ stacking orders is the origin of
Type II phase transition, through which the crystal orientations are preserved.

Finally, from my perspective, can such a memory can be stacked vertically, with a higher number of layers. Yes there are three to five layers of the WTe2 used in BCM but can you put another three to five layers on top of that, and then another. Although the researchers used three, four and five layer configurations, it appears that although it changed the amplitude of the Berry Curvature effect, it didn’t seem to add more states to the transition.. If we were to more layers of WTe2 would we be able to discern say 16 different states (like QLC NAND today).


So there’s a ways to go to productize BCM. But, aside from eliminating the low-temperature requirements, everything else looks pretty doable, at least to me.

I think it would open up a whole new dimension of applications, if we had say 60TB of memory to compute with, don’t you think?


[Updated the title from 60TB to PB to 36PB as I understood how much memory PMEM can provide today…, the Eds.]

Photo Credit(s):

Enhanced LIDAR maps out 45km rather than 215m

I’ve used small LIDAR sensors on toy (Arduino based) robots and they operate well within 1m or so. Ultrasonics sensors are another alternative but we found them very susceptible to noise and surface abrasion. With decent LIDAR sensors used in drones and vehicles, they work up to 215m or so.

But research in the lab (ScienceDaily article: Want to catch a photon, start by silencing the sun) has created LIDAR sensors that uses a novel form of analog/optical noise suppression that is capable of using these same LIDAR sensors and using them to map up to 45km of space.

The researchers were able to add a quantum marker to LIDAR beam photon(s) and then filter beam reflections to only honor those reflected photons with the quantum marker. The ScienceDaily article was based on a Nature Communications article, Noise-tolerant single photon sensitive three-dimensional imager.

What’s been changed?

They call the methodology implemented by their device, Quantum Parametric Mode Sorting or QPMS. It’s not intended to compete with software or computational approaches for noise filtering but rather complement those capabilities with a more accurate LIDAR, that can eliminate the vast majority of noise using non-linear optics (see Wikipedia article on Non-linear optics to learn more)..

It turns out the researchers are able to image space with their new augmented LIDAR using a single photon per pixel. They use an FPGA to control the system and programable ODL(optical delay line, delay’s optical signals), with up conversion single photon detector (USPD, that takes one or more photons at one frequency and converts them to another, higher frequency photon) and a silicon avalanche photo diode (SI-APD, which detects a single photon and creates an avalanche [of multiple electrons?] electrical signal from it.

How well does it work?

To measure the resolution capabilities of the circuit they constructed a 50x70mm (~2×2 3/4″) CNC machined aluminums depth resolution calibration device (sort of like an eye chart only for depth perception) see (2c and 2d below) and were able to accurately map the device column topologies.

They were also able to show enhanced perception and noise reduction when obscuring a landscape (Einstein’s head) with an aluminum screen which would be very hard for normal solutions to filter out. The device was able to clearly reconstruct the image even through the aluminum screen.

The result of all this is an all optical fibre noise reduction circuit. I’m sure the FPGA ,SI-APD, USPD, MLL, Transciever, ODL and MEM are electronics or electro-mechanical devices,, but the guts of the enhanced circuit seems all optical.

What does it mean?

What could QPMS mean for optical fibre communications. It’s possible that optical fibres could use significantly less electro-optical amplifiers, if a single photon could travel 45km without noise.

Also LiFi (light fidelity) or open air optical transmission of data could be significantly improved (both in transmission length and noise reduction) using QPMS. And rone could conceivably use LiFi outside of office communications, such as high bandwidth/low-noise, all optical cellular data services for devices. .

And of course boosting LIDAR length, noise reduction and resolution could be a godsend for all LIDAR mapping today. I readi another article (ScienceDaily: Modern technology reveals … secrets of great, white Maya road) about archeologist mapping the (old) Maya road through the jungles of central America using LIDAR equipped planes. I imagine a QPMS equiped LIDAR could map Mayan foot paths.


DNA IT, the next revolution

I’ve been writing about DNA computing and storage for quite awhile now (see DNA computing and the end of natural evolution, DNA storage and the end of evolution part 2, & Random access DNA object storage system). But in the last few months there’s been a flurry of activity in this space that seems worthy of note.

DNA programing language

First up, A logic programing language for computational nucleic acid devices, a research article in ACS Synthetic Biology magazine. The research describes a new approach to programming DNA computers, that’s uniquely designed to mimic molecular algorithmic capabilities for DNA devices. T\

The language uses logical statements and predicates (reminds me of Prolog). Indeed, the language was modeled after Prolog with equational and molecular extensions to represent DNA functionality. As with Prolog, output is a function of declarative, predicate logic rather than control flow and assignment in normal programming languages. Logic programming takes a different mind set and demands an understanding of formal logic.

The article talks about applications for DNA computing for in vitro (chemical/protien) manufacturing, diagnosis, and therapeutics (operating inside living cells) devices (cells).

DNA storage device

Next up, a recent article in Scientific Reports, Demonstration of end-to-end automation of DNA data storage.

The intent here is to create a fully automated data storage device that uses DNA as its recording media. The current device (seen in the bottom right above) is a lab prototype, that fits on a bench and costs $10K that can store 5 bytes of data with error correction.

The system has three hardware modules: synthesis (writing), storage and sequencing (reading). It also includes encoding and decoding software that translates bits to nucleic acid bases and adds error correction to it. They need to add more bases to be compatible with the sequencing (reading) process.

The limits to storage may have something to do with the size of the storage vessel as well as the size of the DNA string that can be synthesized/sequenced. . Error correction is based on a 6 base (bit) hashing code (less than a byte for 5 bytes). The systems write to read-back time is ~21 hrs.

The device creates many copies of the DNA (data) strand. The 5 byte (“HELLO”) string took 4 micrograms of liquid and yielded 3469 DNA strands, 1973 of which aligned properly to their adapter sequence. Of those properly aligned DNA strands, 30 had extractable payload regions of which 1 was correct, the other 29 were corrupted.

This is a very poor BER (bit error rate). For comparison LTO-7/8 has a BER of 1:10**19 bits, and enterprise disk has a BER of 1:10**15 bits. This DNA storage device has a BER of 3469:1 or ~99.9% of all bits written were lost.

To get a better understanding of the BER, they stored a 100 base (~12 byte) data payload. Of the 25,592 strands created, 286 aligned properly and of those 251 were corrupted, 11 had invalid hashes, and 8 were corrupted but correctable (valid hashes invalid data) and 16 were perfect reads. So 25592 strands had 24 proper reads ~1K:1 BER (not entirely correct because the correctable strands actually had bit errors but we can give them that).

DNA computer architecture

Last up, an IEEE Spectrum article, discussing CalTech Research, DNA computer shows programmable chemical machines are possible, reporting on an article in Nature, Diverse and robust molecular algorithms using reprogrammable DNA self-assembly (paywall). This DNA computer system is made of just DNA and salt water. It computes algorithms on 6 bits of input and uses DNA logic gates.

The Caltech team created 2 input-2-output boolean gates out of DAN sequences, five of these gates are connected to form a computation layer. It supports 6 input and 6 output bits. But you can layer multiple computational levels on top of one another where the output of one layer can be fed in as input to the layer on top of it.

One key, is that the DNA computer self assemblies the computational layer. They use a seed layer as a starter DNA strand and then the input (mixed inside a vial) is attached to this seed layer and then the computational layers are attached one by one until the output is generated.

Each computational layer is made up of DNA computational tiles that attach together sort of like a circuit. they were able to create a 355 instruction set for their DNA computer. In comparison the IBM 360 had a one byte op code (at most 256 instructions).

They have a compiler that allows researchers to write a software algorithm and this translates code into DNA circuit tiles, computational layers and ultimately into a DNA computer.

According to the article, it takes 1-2 hours to grow the computational DNA crystal and another day or so for the computation to complete.

An interesting approach to DNA computation but it’s unclear if they have any branching mechanisms in their “instruction set”. And 6 bit input/output seems a bit limiting. However, by creating boolean gates with DNA, they could recreate any type of electronic computer that exists today.


Put it all together and someday you could have a DNA compute server and storage.

One thing that’s missing is a (packet switched or token ring) network for transferring data between cells (and maybe into and out of DNA storage). They could probably use some sort of vascular (network) system with a way to transfer data from inside a cell to the network and into another cell .

That way they could gang a number of DNA compute servers (cells) together and maybe create a cellular automata machine.

The future of computation looks wetter now.

Photo Credit(s):

Magnonics for configurable electronics

Read an article today in ScienceDaily on [a] New way to write magnetic info … that discusses research done at Imperial College Of London that used a magnetic force microscope (small magnetic probe) to write magnetic fields onto a dense array of nanowires.

Frustrated metamaterials needed

The original research is written up in a Nature article Realization of ground state in artificial kagome spin ice via topological defect driven magnetic writing  (paywall). Unclear what that means but the paper abstract discusses geometrically frustrated magnetic metamaterials.  This is where the physical size or geometrical properties of the materials at the nanometer scale restricts or limits the magnetic states that material can exhibit.

Magnetic storage deals with magnetic material but there are a number of unique interactions of magnetic material when in close (nm) proximity to one another and the way nanowire geometrically frustrated magnetic metamaterials can be magnetized to different magnetic moments which can be exploited for other uses.  These interactions and magnetic moments can be combined to provide electronic circuitry and data storage.

I believe the research provides a proof point that such materials can be written, in close proximity to one another using a magnetic force microscope.

Why it’s important

The key is the potential to create  magnonic circuitry based on the pattern of moments writen into an array of nanowires. In doing so, one can fabricate any electrical circuit. It’s almost like photolithography but without fabs, chemicals, or laser scanners.

At first I thought this could be a denser storage device, but the potential is much greater if electronic circuitry could be constructed without having to fabricate semiconductors. It would seem ideal for testing out circuitry before manufacturing. And ultimately if it could be scaled up, the manufacture/fabrication of electronic circuitry itself could be done using these techniques.

Speed, endurance, write limits?

There was no information in the public article about the speed of writing the “frustrated magnetic metamaterials”. But an atomic force microscope can scan 150×150 micrometers in several minutes. If we assume that a typical chip size today is 150×150 mm, then this would take 1E6 times several minutes, or ~2K days. With multiple scanning force microscopes operating concurrently we could cut this down by a factor of 10 or 100 and maybe someday 1000. 2 days to write any electronic circuit on the order of todays 23nm devices with nanowires and magnetic force microscopes would be a significant advance

Also there was no mention of endurance, write limits or other characteristics we have learned to love with Flash storage. But the assumption is that it can be written multiple times and that the pattern stays around for some amount of time.

How magnetics generate electronic circuits

Neither Wikipedia page, the public article or the paywall articles’ abstract describes how Magnonics can supply electronic circuitry. However both the abstract and the public article discuss applications for this new technology in hardware based neural networks using arrays of densely packed nanowires.

Presumably, by writing different magnetic patterns in these nanowire metamaterials, such patterns can be used to simulate hardware connected neurons. This means that the magnetic information can be overwritten because it can be trained. Also, such magnetic circuits can be constructed to: a) can create different path for electrons to flow through the material; b) can restrict or enhance this electronic flow, and c) can integrate across a number of inputs and determine how electronic flow will proceed from a simulated neuron.

If magnonics can do all that,  it’s very similar to electronic gates today in CPU, GPUs and other electronic circuitry. Maybe it cannot simulate every gate or electronic device that’s found in todays CPUs but it’s a step in the right direction. And magnonics is relatively new. Silicon transistors are over 70 years old and the integrated circuit is almost 60 years old. So in time, magnonics could very well become the next generation of chip technology.

Writing speed is a problem. Maybe if they spun the nanowire array around the magnetic force microscope…


Photo Credits:  Real space observation of emergent magnetic monopoles … Nature article

Realization of ground state in artificial kagome spin ice via topological defect driven magnetic writing, Nature article


Research reveals ~liquid nitrogen temperature molecular magnets with 100X denser storage

Must be on a materials science binge these days. I read another article this week in on “Major leap towards data storage at the molecular level” reporting on a Nature article “Molecular magnetic hysteresis at 60K“, where researchers from University of Manchester, led by Dr David Mills and Dr Nicholas Chilton from the School of Chemistry, have come up with a new material that provides molecular level magnetics at almost liquid nitrogen temperatures.

Previously, molecular magnets only operated at from 4 to 14K (degrees Kelvin) from research done over the last 25 years or so, but this new  research shows similar effects operating at ~60K or close to liquid nitrogen temperatures. Nitrogen freezes at 63K and boils at ~77K, and I would guess, is liquid somewhere between those temperatures.

What new material

The new material, “hexa-tert-butyldysprosocenium complex—[Dy(Cpttt)2][B(C6F5)4], with Cpttt = {C5H2tBu3-1,2,4} and tBu = C(CH3)3“, dysprosocenium for short was designed (?) by the researchers at Manchester and was shown to exhibit magnetism at the molecular level at 60K.

The storage effect is hysteresis, which is a materials ability to remember the last (magnetic/electrical/?) field it was exposed to and the magnetic field is measured in oersteds.

The researchers claim the new material provides magnetic hysteresis at a sweep level of 22 oersteds. Not sure what “sweep level of 22 oersteds” means but I assume a molecule of the material is magnetized with a field strength of 22 oersteds and retains this magnetic field over time.

Reports of disk’s death, have been greatly exaggerated

While there seems to be no end in sight for the densities of flash storage these days with 3D NAND (see my 3D NAND, how high can it go post or listen to our GBoS FMS2017 wrap-up with Jim Handy podcast), the disk industry lives on.

Disk industry researchers have been investigating HAMR, ([laser] heat assisted magnetic recording, see my Disk density hits new record … post) for some time now to increase disk storage density. But to my knowledge HAMR has not come out in any generally available disk device on the market yet. HAMR was supposed to provide the next big increase in disk storage densities.

Maybe they should be looking at CAMMR, or cold assisted magnetic molecular recording (heard it here, 1st).

According to Dr Chilton using the new material at 60K in a disk device would increase capacity by 100X. Western Digital just announced a 20TB MyBook Duo disk system for desktop storage and backup. With this new material, at 100X current densities, we could have 2PB Mybook Duo storage system on your desktop.

That should keep my ever increasing video-photo-music library in fine shape and everything else backed up for a little while longer.


Photo Credit(s): Molecular magnetic hysteresis at 60K, Nature article


Big science/big data ENCODE project decodes “Junk DNA”

Project ENCODE (ENCyclopedia of DNA Elements) results were recently announced. The ENCODE project was done by a consortium of over 400 researchers from 32 institutions and has deciphered the functionality of so called Junk DNA in the human genome. They have determined that junk DNA is actually used to regulate gene expression.  Or junk DNA is really on-off switches for protein encoding DNA.  ENCODE project results were published by Nature,  Scientific American, New York Times and others.

The paper in Nature ENCODE Explained is probably the best introduction to  the project. But probably the best resource on the project computational aspects comes from these papers at Nature, The making of ENCODE lessons for BIG data projects by Ewan Birney and ENCODE: the human encyclopedia by Brendan Maher.

I have been following the Bioinformatics/DNA scene for some time now. (Please see Genome Informatics …, DITS, Codons, & Chromozones …, DNA Computing …, DNA Computing … – part 2).  But this is perhaps the first time it has all come together to explain the architecture of DNA and potentially how it all works together to define a human.

Project ENCODE results

It seems like there were at least four major results from the project.

  • Junk DNA is actually programming for protein production in a cell.  Scientists previously estimated that <3% of human DNA’s over 3 billion base pairs encode for proteins.  Recent ENCODE results seem to indicate that at least 9% of this human DNA and potentially, as much as 50% provide regulation for when to use those protein encoding DNA.
  • Regulation DNA undergoes a lot of evolutionary drift. That is it seems to be heavily modified across species. For instance, protein encoding genes seem to be fairly static and differ very little between species. On the the other hand, regulating DNA varies widely between these very same species.  One downside to all this evolutionary variation is that regulatory DNA also seems to be the location for many inherited diseases.
  • Project ENCODE has further narrowed the “Known Unknowns” of human DNA.  For instance, about 80% of human DNA is transcribed by RNA. Which means on top of the <3% protein encoding DNA and ~9-50% regulation DNA already identified, there is another 68 to 27% of DNA that do something important to help cells transform DNA into life giving proteins. What that residual DNA does is TBD and is subject for the next phase of the ENCODE project (see below).
  • There are cell specific regulation DNA.  That is there are regulation DNA that are specifically activated if it’s bone cell, skin cell, liver cell, etc.  Such cell specific regulatory DNA helps to generate the cells necessary to create each of our organs and regulate their functions.  I suppose this was a foregone conclusion but it’s proven now

There are promoter regulatory DNA which are located ahead and in close proximity to the proteins that are being encoded and enhancer/inhibitor regulatory DNA which are located a far DNA distance away from the proteins they regulate.

I believe it seems that we are seeing two different evolutionary time frames being represented in the promoter vs. enhancer/inhibitor regulatory DNA.  Whereas promoter DNA seem closely associated with protein encoding DNA, the enhancer DNA seems more like patches or hacks that fixed problems in the original promoter-protein encoding DNA sequences, sort of like patch Tuesday DNA that fixes problems with the original regulation activity.

While I am excited about Project ENCODE results. I find the big science/big data aspects somewhat more interesting.

Genome Big Science/Big Data at work

Some stats from the ENCODE Project:

  • Almost 1650 experiments on around 180 cell types were conducted to generate data for the ENCODE project.   All told almost 12,000 files were analyzed from these experiments.
  • 15TB of data were used in the project
  • ENCODE project internal Wiki had 18.5K page edits and almost 250K page views.

With this much work going on around the world, data quality control was a necessary, ongoing consideration.   It took about half way into the project before they figured out  how to define and assess data quality from experiments.   What emerged from this was a set of published data standards (see data quality UCSC website) used to determine if experimental data were to be accepted or rejected as input to the project.  In the end the retrospectively applied the data quality standards to the earlier experiments and had to jettison some that were scientifically important but exhibited low data quality.

There was a separation between the data generation team (experimenters) and the data analysis team.  The data quality guidelines represented a key criteria that governed these two team interactions.

Apparently the real analysis began when they started layering the base level experiments on top of one another.  This layering activity led to researchers further identifying the interactions and associations between regulatory DNA and protein encoding DNA.

All the data from the ENCODE project has been released and are available to anyone interested. They also have provided a search and browser capability for the data. All this can be found on the top UCSC website. Further, from this same site one can download the software tools used to analyze, browse and search the data if necessary.

This multi-year project had an interesting management team that created a “spine of leadership”.  This team consisted of a few leading scientists and a few full time scientifically aware project officers that held the project together, pushed it along and over time delivered the results.

There were also a set of elaborate rules that were crafted so that all the institutions, researchers and management could interact without friction.  This included rules guiding data quality (discussed above), codes of conduct, data release process, etc.

What no Hadoop?

What I didn’t find was any details on the backend server, network or storage used by the project or the generic data analysis tools.  I suspect Hadoop, MapReduce, HBase, etc. were somehow involved but could find no reference to this.

I expected with the different experiments and wide variety of data fusion going on that there would be some MapReduce scripting that would transcribe the data so it could be further analyzed by other project tools.  Alas, I didn’t find any information about these tools in the 30+ research papers that were published in the last week or so.

It looks like the genomic analysis tools used in the ENCODE project are all open source. They useh the OpenHelix project deliverables.  But even a search of the project didn’t reveal any hadoop references.


The ENCODE pilot project (2003-2007) cost ~$53M, the full ENCODE project’s recent results cost somewhere around $130M and they are now looking to the next stage of the ENCODE project estimated to cost ~$123M.  Of course there are 1000s of more human cell types that need to be examined and ~30% more DNA that needs to be figured out. But this all seems relatively straight forward now that the ENCODE project has laid out an architectural framework for human DNA.

Anyone out there that knows more about the data processing/data analytics side of the ENCODE project please drop me a line.  I would love to hear more about it or you can always comment here.


Image: From Project Encode, Credits: Darryl Leja (NHGRI), Ian Dunham (EBI)