Cities and The Future of Fresh Water: Desalination and Deep Tunnels

It’s clear that seven billion humans cannot continue to rely on Earth’s natural cycles to provide for our increasingly urban civilization. To sustain our current and future needs, and to protect the rest of life on Earth, we need reliable systems that minimise our impact on the environment.

Clean fresh water provision and sewage treatment are two of the foundations of civilization – which together provide a huge boost in health, quality of life and productivity. Increasing demands on the natural water cycle and ageing legacy systems (that date back in some areas to Victorian or even Roman engineering) mean that new technologies and novel large-scale engineering projects are needed.

On the supply side: 96.5% of Earth’s water is locked up in the salty seas, while 40% of people on the planet already suffer from water shortage*, and half the world’s people live within 60km of a coastline* – so it’s obvious that desalination is a key water supply technology.
Advances in semi-permeable membrane production allow for fast high volume desalination, especially using reverse osmosis – where hydrostatic pressure is used to push fresh water through the membrane, leaving salts and micro-organisms safely trapped on the other side.
(*UN figures)

Even in the UK, London is at risk of water restrictions in times of drought, so the Thames Water Desalination Plant was built to offset this. The plant (in Beckton, East London) runs entirely on renewable energy and can take in brackish water from the tidal River Thames – removing salt using the reverse osmosis process to produce 150 million litres of clean fresh drinking water each day – enough for nearly one million people. Once treated the water is transferred to North East London in a new 12km long pipeline, which can hold a staggering 14 million litres of water.

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Photo: London at night, from the International Space Station. Credit: NASA/JSC
(public domain)

The flip-side of sustainable water management is sewage treatment: to prevent the spread of disease, minimise pollution reaching natural waterways, and to reclaim fertilizer for agriculture. Increasingly large cities produce massive sewage flows, requiring new engineering works on a heroic scale that might surprise even the late great engineering genius Isambard Kingdom Brunel.

Greater London has a population of over 8.7 million people and growing, yet like many cities it still has an extensive legacy combined sewer system, which also collects surface runoff. During heavy rainstorms excess rainwater and sewage automatically overflows to prevent flooding of the sewage treatment works. These Combined Sewer Overflows (CSOs) now pour 39 million tonnes of mixed stormwater and untreated sewage out of the 150 year old Victorian sewer system into the River Thames and River Lea every year.

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Image: Combined Sewer System. Credit: EPA (public domain)

To stop this pollution two huge tunnels are being commissioned to store the excess during storms, so it can be safely treated later: the 7.2m wide, 6.9km long Lee Tunnel is the first – it runs underneath the London Borough of Newham, from London’s largest CSO at Abbey Mills to the recently much enlarged Beckton Sewage Treatment Works.

The Lee Tunnel is London’s deepest-ever tunnel, because its shallowest point was set at 75m deep so as to capture flows from the lowest point of the massive new Thames Tideway Tunnel; a 7.2m wide, 25km long tunnel currently under construction below the River Thames – which will connect 34 of London’s most polluting CSOs to the Lee Tunnel, and hence to the Treatment Works.

While other smaller cities such as Philadelphia, USA have used various approaches under the umbrella term of Sustainable Drainage Systems (SuDS) to tackle excess storm flows, London has six times the population and sits on layers of impermeable clays and saturated gravels that severely limit the flows SuDS methods can cope with – which is why the giant Lee and Tideway Tunnels are essential to fix London’s river pollution problem.

UFEx Ep.6: Incredible Osiris-Rex Mission Launched to bring back Samples from Potentially Hazardous Near Earth Asteroid ‘Bennu’!

Image: to-bennu-and-back_mp4_4Images: NASA

Welcome to Episode 6 of Ultra Frontier Explorer with Dr Jon Overton.
In this episode there’s:
– Epic footage of NASA’s Osiris-Rex rocket launch on its journey from Earth to the potentially hazardous near Earth asteroid Bennu.
– All about WHY this Sample Return Mission is so exciting: what it might tell us about the Solar System and Earth’s past, including the origins of life on Earth. Also, how this mission will gather data to help protect us from the danger of catastrophic collisions in the future!
– Find out what the ‘Yarkovsky Effect’ is, and why understanding it is vital for Planetary Security and the survival of the Human Race versus Asteroid impacts!

Ultra Frontier Explorer- Episode 5: Celebrating the 10th Anniversary of New Horizons launch. Key findings from the Pluto & Charon flyby, plus latest photos & footage

It’s now the 10th Anniversary of New Horizons launch, and six months since the historic Pluto & Charon flyby (July 14th, 2015). New Horizons has spent those months beaming the data it collected back to us here on Earth, across 5 billion km of space. Recently, the New Horizons team have released some excellent photos and footage, and there has been an entire scientific conference focussing solely on the data from New Horizons (no doubt the first of many such conferences).

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Scroll down for UFEx Episode 5, which is Part 2* of my video coverage of New Horizons ground-breaking mission to flyby Pluto & Charon, (and onward, deeper into the Kuiper Belt), featuring new photos and footage, and covering:
– Some of the engineering that went into New Horizons construction to protect it from any micro-meteorite collisions.
– How New Horizons instruments are powered so far from the Sun.
– Some perspective on navigating New Horizons safely through the multi-body Pluto system at over 49,000km/hr.
– Fascinating geological and meterological phenomena on Pluto & Charon, and proposed explanations for these, including: the composition of Pluto’s “heart” (Sputnik Planum) and the mountain ranges around it (Hilary Montes, Norgay Montes); the discovery of what appears to be two enormous cryo-volcanoes (Wright Mons and Picard Mons) and their implications for Pluto’s interior structure; the probable composition and origin of the reddish-brown material (tholins) patchily distributed on much of Pluto’s surface and at one pole of Charon, (and what that material might have had to do with the origin of life on Earth); plus an explanation for Pluto’s breathtaking blue sky.
– And finally, which of the myriad unexplored Kuiper Belt worlds will be New Horizons next destination, and when it will arrive there.

All of this and more, covered in less than 23minutes! So make yourself a cuppa, sit back and discover how much more we now know about the mysterious worlds of Pluto & Charon than we did before flyby.

*See below for ‘UFEx Episode 4, “New Horizons Journey to Pluto” Part 1’ – covering New Horizon’s gravitational slingshot around Jupiter (9 years ago) and its observations of the Jovian system, especially the Galilean moons.

“Bunker busting” Antibody-antibiotic-conjugates (AACs) successfully used to target MRSA bacteria hiding inside the host’s cells

One of the difficulties in combating MRSA is that (Staphylococcus aureus) bacteria have the ability to live inside the host’s cells where they are effectively sheltered from the action of systemic antibiotics – it is this reservoir of infection that provides the seed for the relapses that are characteristic of MRSA.

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S. aureus bacteria escaping a white blood cell, x20,000 mag.
Credit: NIAID – Creative Commons CCBY2

A large team of researchers from Genentech in the USA and Symphogen in Denmark has developed a method to destroy these intracellular S.aureus bacteria that would otherwise be protected from antibiotics. The team used a novel conjugate of the antibiotic rifalogue together with monoclonal antibodies. These antibody-antibiotic-conjugates (AACs) are specifically immuno-targeted to S.aureus. The AACs remain inactive in the bloodstream, and only become active in the presence of the bacteria inside the host´s cells.

Once the AACs are taken into the host’s cells they are transported deeper – into the phagolysosomes which enclose the bacteria inside the cell. The phagolysosomes contain a proteolytic environment, and the protease enzymes found there cleave a small peptide group from the AACs – activating them. The active AACs are then able to bind to the surface of the bacteria effectively delivering their antibiotic payload to the infection’s hidden “bunker”.

Infected mice were treated with the AACs, and the team found this new treatment was much more effective than a systemic antibiotic (vancomycin). This work confirms the importance of intracellular S.aureus as a reservoir of MRSA infection, and raises the exciting possibility that these AACs might eventually be used to treat humans. The targeted approach of AACs would avoid damaging the patient’s beneficial microflora, and if their use becomes routine it would probably reduce the rate at which bacteria in general evolve resistance to any one particular antibiotic.

(This study was published in Nature:
Sophie M. Lehar et al. Novel antibody–antibiotic conjugate eliminates intracellular S. aureus, Nature (2015). DOI: 10.1038/nature16057 http://www.nature.com/nature/journal/v527/n7578/full/nature16057.html )

Child’s life saved from leukemia in ground-breaking use of gene-edited immune system cells

Doctors at Great Ormond Street Hospital (GOSH) successfully used “off the shelf” genetically engineered white blood cells (T-cells) in a last ditch effort to treat a one-year old girl, called Layla, who was suffering from acute lymphoblastic leukemia (ALL) that had resisted chemotherapy. This is the world’s first instance of this targeted cancer therapy in a human patient.

To achieve this GOSH doctors worked with research scientists at University College London’s (UCL) Institute of Child Health (ICH) and biotech company Cellectis. The gene-edited T-cells were modified using a “molecular toolkit” that scientists have pirated from a few genes found in certain bacteria – especially a biological editing tool called TALEN.
TALEN is a combination of a modular protein (TAL) that can effectively be “programmed” to find and bind very specific DNA sequences, together with an endonuclease (EN) which is a protein that can cut DNA, ready to replace that gene with the version desired.

The modified T-cells are called UCART19 cells, and they are produced to fight leukemia in a two step process:
First, they have a gene that programs for a characteristic cell surface protein deleted – so the UCART19 cells will be “invisible” and remain safe from the anitibodies that are given to leukemia patients to destroy their existing, diseased immune system.
Secondly, the T-cells have the gene for the CAR19 surface protein added – CAR19 will bind the UCART19 cells to a different protein called CD19, which is only found on the surface of immature white cells (called “blasts” – lymphoblasts in ALL) that proliferate in leukemia and “crowd out” other healthy blood cells, thus causing the disease symptoms. Once bound to the leukemia cells (lymphoblasts) the UCART19 cells recognise them as foreign and destroy them.

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(Above: The blood stream of a healthy subject vs. a leukemia patient.
RBCs = Red Blood Cells. WBCs = White Blood Cells.

Public domain image, credit: NCI, Alan Hoofring.
Modified by J.Overton)

Clinical trials taking place at the moment normally begin with white blood cells taken from the patient because these run least risk of causing auto-immune problems, but this “bespoke” method of production is expensive. However, due to the chemotherapy and highly agressive nature of the leukemia she suffered, little Layla did not have enough white blood cells left to work with, so the team gave her “off the shelf” UCART19 cells created from donated T-cells.

Previously, this experimental treatment had only been tested on mice in the lab, in fact it was so new that GOSH had to convene an emergency ethics meeting to decide whether Layla should receive it. As routine chemotherapy and a bone marrow transplant had already failed to help Layla, and her condition was worsening, all the doctors had left to offer was either palliative care to relieve her suffering during terminal illness, or the hope of possible recovery with the UCART19 cells. So, together with Layla’s parents, they decided to opt for treatment.

After about two weeks of receiving the UCART19 cells, Layla got a rash which is characteristic of the expected immune response, and a few weeks later results showed her system was clear of leukemia cells. After two months Layla received a second bone marrow transplant, which was successful, and once her healthy blood cell count was high enough she was able to return home with her family to recuperate further. While it is still too early to declare Layla cured, and she is still being monitored in case the leukemia returns, so far she is doing well.

Hopefully, further trials will show similar success and this targeted treatment may then become more widely available for other leukemia sufferers.

(Clinical information from GOSH Press Release, biotechnology information from New Scientist  and The Tech Museum of Innovation)

Heart Transplant Breakthrough comes to UK: “Dead” Donor Heart Revived and Transplanted Successfully

Last year surgeons in Sydney, Australia pioneered a ground-breaking new technique that should increase the availability of viable donor hearts. In what was described as the biggest heart transplant breakthrough in a decade, two patients received hearts that had been restarted following the terminal cardiac arrest of donor circulatory death (DCD). Previously, hearts had to be taken from donors who had suffered brain death, but whose hearts were still beating, which severely limited the number of donor organs available.

This year, medics at Papworth Hospital in Cambridge, UK successfully carried out a heart transplant using the new procedure. The patient recovered rapidly, only spending 4 days in the hospital’s critical care unit, before being well enough to return home.

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(Public domain image, colourised by J.Overton)

The new technique, which was first developed by researchers from St. Vincent’s Hospital in Sydney and the Victor Chang Cardiac Research Institute, can be applied to hearts that have stopped for as long as 20 minutes. First, the unbeating heart is restarted inside the donor’s body, where it is assessed for any problems using ultrasound over a 50 minute period. The heart is then removed from the donor and is kept beating, warmed and perfused with blood by an organ care system (a “heart-in-a box” machine) for up to 3 hours before transplantation.

As reported in the Guardian: Consultant surgeon at Papworth, Stephen Large, predicted that, “the use of this group of donor hearts could increase heart transplantation by up to 25% in the UK alone.” Notably, five other specialist heart transplant centres around the UK plan to adopt the procedure soon, which may reduce waiting times for heart transplant patients.

This development came just two years after the world’s first successful “warm liver” transplant in King’s College Hospital, London. Using the “OrganOx” organ support system (developed over a 15 year period by scientists at Oxford University), the liver was warmed to body temperature and kept perfused with blood. This system can keep the donated liver alive outside the body for up to 24 hours – twice as long as a liver kept “on ice” – which increases the time window available for donor-patient matching, transport and transplantation.

It seems that the old technique of keeping donor organs chilled prior to transplant will soon be superseded by these new warm “organ-in-a-box” methods, to the great benefit of patients.

Ultrasound Treatment for Dementia Improves Memory in Mice

An Australian research group has used ultrasound to successfully improve memory in mice suffering from dementia. The ultrasound treatment helps the mice break down peptide plaques in their brains that seem to contribute to their Alzheimer’s-like memory loss.

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(Public domain photo, credit: NASA)

Scientists worked with mice who have a genetic predisposition to produce greater than usual amounts of the peptide beta-amyloid. Just like human Alzheimer’s patients these mice have a build up of beta-amyloid brain plaques and suffer memory problems.

The mice received a non-invasive treatment with ultrasound once a week for five to seven weeks. The treated mice showed between a 50% reduction to complete clearance of brain plaques, without any apparent harm to their brain tissue. They also performed much better in memory tests, such as navigating mazes, in contrast to untreated mice.

The researchers showed that treatment had stimulated microglial cells, which are part of the brain’s immune system, these microglial cells then engulfed and broke down the beta-amyloid plaques.

One of the researchers, Juergen Goetz of the University of Queensland (Brisbane), said he was very excited by this result, but he pointed out that research is still at a very early stage, and we are some years away from human tests. The treatment will next be trialled in sheep, and data should be obtained from those experiments late in 2015.

It’s worth noting that although the mice in this study suffered from beta-amyloid plaques they did not have the cell damage and lost neural connections that are the other two main features seen in the brains of human Alzheimer’s patients. Nevertheless, this looks like a promising line of ongoing research into a disease that currently blights the lives of 50 million sufferers worldwide.

(This study was published in the journal Science Translational Medicine.)

Welcome to Once and Future Science

Welcome to Once and Future Science, where I’ll be blogging about scientific & technological advances in general, and advances in space science, medicine and energy in particular.

I’m Dr Jon Overton – you might be familiar with my space science series Ultra Frontier Explorer (that I produce for www.alwaysaround.net ) – you can catch up on UFEx here: https://www.youtube.com/playlist?list=PLtHji6t6ST4TMSidaU3SGEE1NSNI_QrHE

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The background image I’ve used above is “The Day The Earth Smiled” which is an amazing composite photograph of Saturn, its rings and moons, with some planets of the Inner Solar System in the background. The Earth, as seen from 898million miles away (on Sat 19th July 2013) appears as the Pale Blue Dot in the lower right of the image. This image was produced by NASA’s Cassini mission, and is public domain, credit: NASA/JPL. You can see annotated and larger versions of this image here: http://www.nasa.gov/mission_pages/cassini/multimedia/jpl/pia17172.html#.VjVW8qe6tH0