All posts by Andrew Shorthouse

How far is a bridge too far? Matthew Gilbert PhD 5th July 2021

This was every bit an inform­at­ive talk laced with some quite chal­len­ging math­em­at­ical con­cepts which inform on best bridge design.

Computational mod­el­ling and optim­isa­tion are able to pre­dict how a bridge’s com­pon­ents and struc­tures will behave under spe­cific con­di­tions, and thereby improv­ing design, effi­ciency and man­u­fac­tur­ing tech­nique e.g. with 3D print­ing

What are the span limits for any bridge form?


For example, those made from stone have a very lim­ited span. Steel fares a bit better. So what altern­at­ive forms are more effi­cient and allow for a greater span?


Robert Hooke 1635–1703 invest­ig­ated the shape of an arch by hanging weights from a straight beam. He then inver­ted this shape to deduce the optimal arch shape for effi­cient bridge con­struc­tion.

Forces gen­er­ated by the weight of a stone arch bridge limit span to just 120m.

Other mater­i­als e.g. rein­forced con­crete or metal can extend that limit to around 400m.The steel rail bridge at Newcastle upon Tyne would be a good example.

Fig 1 Types of arches 

Cable sup­por­ted

The most usual form is the sus­pen­sion bridge, for example the Humber Bridge

Fig 2 Humber Bridge

The main towers were built first and linked together with a pair of cables spun each side of the bridge and ver­tical cables hanging down to sup­port the deck. Deck sec­tions were then made to com­plete it. It was opened 40 years ago and was the inspir­a­tion for Dr Gilbert’s future career in civil engin­eer­ing on a school trip.

Other examples are the planned Halsafjorden in Norway which will span 2050m. Wind engin­eer­ing aspects are import­ant with a bridge of this size, with wind tunnel aero­dy­namic test­ing, wind buf­feting, flut­ter and vortex induced vibra­tion lead­ing to ongo­ing modi­fic­a­tion of the bridge deck geo­metry. There will be a float­ing tower in the middle anchored to the fjord bed below.

The span of a simple sus­pen­sion bridge is the dis­tance of sus­pen­ded road­way between towers and the 2km span of the Akashi Kaikyõ Bridge in Japan is the limit.

Cable-stayed form

Long span arches need cable-stays. Cables dir­ectly con­nect the towers to the road­way by a series of diag­onal stays between tower and deck. This bridge form is effi­cient as the main con­struc­tion steps are sim­ul­tan­eous. The main tower with pro­gress­ive lat­eral deck exten­sion on each side increases the span. Deck exten­sions then meet and are joined together.

Fig 3 Queensferry Crossing

The Queensferry Forth Replacement Crossing is a 4-span cable-stayed bridge with main spans of 650m

Hybrid sus­pen­sion and cable-stayed bridges are even more effi­cient. Diagonal cables are dropped to sup­port the deck

while being exten­ded. The middle part is sup­por­ted by main cables. The longest bridge in the world, 164.8km long, is the hybrid Danyang Kunshan Grand Bridge in China

Danyang Kunshan Grand Bridge in China









The best form of bridge

The most import­ant ques­tion is the optimal min­imal volume of mater­ial required to build the most resi­li­ent struc­ture. As bridge span increases, pro­gress­ively more of the struc­ture is neces­sary to simply carry its own weight, thereby lim­it­ing the span.

Steel cur­rently is the mater­ial of choice, so the only altern­at­ive at present is to adapt the effi­ciency of bridge design. A simple bracket with an attached weight is a good ana­logy. A large dif­fer­ence in volume is achieved using an ortho­gonal bracket shape (Fig 5).

Fig 5 — orthogaonal is on the left

Computer mod­el­ling has shown that com­plex ortho­gonal lay­outs are best for achiev­ing equi­lib­rium of bridge struc­ture (Fig 6).

Fig 6

But not all ten­sion and com­pres­sion ele­ments are ortho­gonal because the weight of the struc­ture itself needs to be factored in.

Development of the ideal is ongo­ing. There are eco­nomic issues, and factors such as wind load­ing and mater­i­als; when sub­sti­tu­tion of steel by carbon graphene becomes tech­nic­ally feas­ible, the app (“try it your­self”) sug­gests the pos­sib­il­ity of a 10 km span.

Most of the forces on a bridge are dir­ec­ted down the tower. A new bridge form needs less mater­ial largely because the forces from the deck are trans­mit­ted from the super­struc­ture to the found­a­tions. This is achieved by keep­ing load paths short and main­tain­ing wide angles between the tensile and com­press­ive ele­ments. Sharp angles give large com­pres­sion forces. Changing the compression/tension ratio optim­ises change in shape and type of bridge

A bridge too far

A bridge has been pro­posed to link the UK with Ireland. Bridge length is a bigger prob­lem fur­ther south between Wales and Eire.  Scotland on the other hand adds to jour­ney time from England and the con­tin­ent. There are con­sid­er­able fin­an­cial, struc­tural and polit­ical chal­lenges but it is feas­ible. A com­bined tunnel bridge would be pos­sible.

Lady Mary Wortley Montagu 1689–1762 — Roger England -19th April 2021

Early life

Lady Mary Wortley Montagu

Lady Mary Wortley Montagu (neé Pierrepont) is recog­nised as one of the great female intel­lec­tu­als of the 18th cen­tury.

She was the daugh­ter of the Duke of Kingston-upon-Hull, born in 1689. Between 1692 and 1700 she went to her grand­mother at West Dean near Salisbury, then to Thoresby Hall near Ollerton. Here she was edu­cated (badly) by a gov­erness, but intel­lec­tu­ally motiv­ated, she taught her­self Latin and immersed her­self in books.

In London she met Edward Wortley Montagu, grand­son of the Earl of Sandwich. Through his sister Anne Wortley, Edward made it known he was keen on Lady Mary and they con­tin­ued to cor­res­pond and meet secretly. However arranged mar­riages were common amongst the aris­to­cracy and Clotworthy Skeffington, an Irish Peer, was her father’s altern­at­ive idea of a suit­ably wealthy aris­to­cratic suitor. Edward’s counter pro­posal was flatly rejec­ted by Lord Dorchester so they eloped and mar­ried in 1712. Their son Edward junior  was born in 1713.

Lady Mary Wortley Montagu with her son Edward

The fol­low­ing year Edward (senior) accep­ted accep­ted the post of Junior Commissioner of the Treasury. Mary rose to the highest levels of the social ladder in London and was intro­duced to the royal court. A bit of a scan­dal monger, she wrote anonym­ous poems for The Spectator between 1714–16, describ­ing mem­bers of roy­alty as “block­heads”.

In 1716 Edward was posted to Constantinople as British ambas­sador to nego­ti­ate an end to the Austro-Turkish War. They trav­elled over­land via Vienna, accom­pan­ied by 200 Turkish troops, phys­i­cian and ser­vants. A daugh­ter was born in 1718. She wrote “Letters from Turkey” and is cred­ited as the first female travel writer.

Lady Mary vis­ited zena­nas in the Ottoman Empire to learn about the cus­toms of segreg­ated Muslim and Hindu women. She wrote about a visit to a Turkish bath, her gender and status provid­ing access to female spaces that were no-go areas for men. The Ottoman women were hor­ri­fied by her stays (of cor­setry), believ­ing her to be “so locked up in that machine that it was not in my own power to open it, which con­triv­ance they attrib­uted to my hus­band”.  Her writ­ing was some­what erotic.

A paint­ing, inspired by Mary Wortley Montagu’s detailed descrip­tions of nude ori­ental beau­ties, by Jean Auguste Dominique Ingres

She looked far more com­fort­able there out of cor­setry.

Lady Montagu in Turkish Dress by Jean-Étienne Liotard c.1756


Smallpox was first recor­ded in China in third cen­tury and by the tenth cen­tury nasal inocu­la­tion of pus­tu­lar mater­ial to achieve immunity was prac­tised.

Smallpox inocu­la­tion in China

Pox-swaddling in infec­ted clothes had been used for cen­tur­ies in parts of Wales to gain immunity. The English were unaware.

Lady Mary Wortley Montagu intro­duced vari­ola­tion to England, based on her Turkish exper­i­ence where small­pox was rife. She had sur­vived the dis­ease her­self at the age of 26 but her face was dis­figured. Her brother had died from it two years earlier in 1713. She was there­fore alert to the its implic­a­tions and in 1717 she wrote about the effect­ive Turkish prac­tise of vari­ola­tion (inocu­la­tion) for small­pox in “Letter to a Friend”. Pustules from an infec­ted person were scratched into the skin of an unin­fec­ted person. Acquired immunity res­ul­ted in just mild dis­ease and no (doc­u­mented) mor­tal­ity with min­imal scar­ring.

She per­suaded Charles Maitland, embassy sur­geon, to inocu­late her 5 year old son Edward. Back in England in 1721 her daugh­ter Mary (many years later buried in Wortley church) was inocu­lated by Maitland, arous­ing the interest of Caroline of Ansbach, Princess of Wales. Maitland was reluct­ant to do it in the public glare of London, fear­ing the poten­tial scan­dal of unin­ten­ded death with an untried remedy! He would only agree on con­di­tion that rep­res­ent­at­ives of the Royal College of Physicians were present as wit­nesses.

Controversy raged. More “clin­ical trials” were needed. In 1721 the King agreed to pardon six con­demned Newgate pris­on­ers if they agreed to volun­teer for vari­ola­tion. All sur­vived and were pardoned. Maitland kept impec­cable records.

Six Newgate pris­on­ers pardoned

In 1722, six orphans also sur­vived vari­ola­tion under scru­tiny and royal approval was finally gran­ted. The Princess of Wales had already lost one daugh­ter from small­pox and wished to be inocu­lated, together with her son and two other daugh­ters. Even then, the “anti­vaxxers” were hard at work.

Variolation was not com­pletely safe. Deaths sub­sequently happened. In the 1760s there were mul­tiple anec­dotal reports of pro­tec­tion against small­pox by prior cowpox infec­tion, a closely related virus but dis­tinct from small­pox and never pro­du­cing other than mild symp­toms in humans. Cowpox was par­tic­u­larly common in milk­maids. In 1774, farmer Benjamin Jesty inocu­lated his family with pus­tu­lar mater­ial from infec­ted cows and the chil­dren remained healthy in a sub­sequent small­pox epi­demic.

Edward Jenner vac­cin­at­ing

In 1796 Edward Jenner ( inocu­lated James Phipps with cowpox from milk­maid Sarah Nelms. He was the first to apply sci­ence when he later vari­olated Phipps, this time with actual small­pox, and he was immune. Jenner’s res­ults were met with ini­tial scep­ti­cism but by 1800 vac­cin­a­tion was increas­ingly accep­ted. The term “vac­cin­a­tion” was a Latin nod to its origin (vacca=cow).

The modern small­pox vac­cine con­tains vac­cinia virus, closely related but genet­ic­ally dis­tinct from cowpox. Smallpox was declared erad­ic­ated by WHO in 1980 shortly after an acci­dental, but fatal, labor­at­ory escape in Birmingham in 1978 (COVID ana­logy here?). The blog­ger con­siders him­self lucky to remain alive after his stu­dent days doing a vir­o­logy course at St Mary’s where the only live English stocks of small­pox virus were kept only feet away in a freezer at the time before their final jour­ney via Porton Down to the Centers for Disease Control and Prevention (CDC) in Atlanta Georgia.

The blog­ger also recalls the ori­ginal pre­served hide of the donor cow Blossom  in the lib­rary when he worked at Jenner’s alma mater, St George’s Hospital at Hyde Park Corner. When the hos­pital was trans­ferred to Tooting in 1977 it went to its cur­rent home at the Jenner Museum at Berkeley, Gloucestershire.


Lady Mary Wortley Montagu’s later years

Lady Mary con­tin­ued to write satir­ical art­icles and pub­lished her news­pa­per “Nonsense of Common-Sense” but her out­spoken beha­viour was increas­ingly embar­rass­ing to her hus­band, which led to sep­ar­a­tion and divorce. When she was 47 years old she met 24 year old Algarotti which caused a bit of a scan­dal. She left for Venice but the fact that Algarotti was bisexual didn’t help. Having then settled in Avignon in 1742, the English and French went to war in 1744 and she returned to Italy.

Her son Edward was a tear­away, drunk­ard, burg­lar and bigam­ist with an ille­git­im­ate child, before absolv­ing him­self with a dis­tin­guished career in the army. They didn’t get on.

Lady Mary joined Count Palazzi in Gottolengo to lead a quiet rural life before return­ing to England, by which time she had writ­ten her travel diar­ies. Lady Mary’s daugh­ter refused pub­lic­a­tion, but shortly after her death from breast cancer in 1762, they were pub­lished in the Netherlands from copies of the ori­gin­als which had been quietly stolen and returned without her know­ledge.

Lady Mary Wortley Montagu’s extens­ive body of work is freely avail­able in print but has been poorly recog­nised until now, but per­haps this is about to change


Surviving Warsaw 1939–45 — Dr Marek Szablewski — 1st March 2021

Dr Marek Szablewski

What a fant­astic, emo­tion­ally charged talk by Marek about his family ori­gins in Warsaw during the Nazi occu­pa­tion of Poland!

Marek him­self grew up in Sheffield in the 1960s, leav­ing for Durham in 1992 for an aca­demic career in applied chem­istry and phys­ics.

Much of his talk centred on the war­time exper­i­ence of his father. Witold Szablewski, per­haps unusu­ally, spoke freely to Marek before his death in 2008. This was the cata­lyst for the award of a Winston Churchill Fellowship in 2011 to explore the family’s involve­ment during the occu­pa­tion in more detail. The aim was to ensure that the hor­rors of that time are never for­got­ten or diluted. In the words of Primo Levi, an Auschwitz sur­vivor, “It happened, there­fore it can happen again: this is the core of what we have to say. It can happen, and it can happen every­where”.

Poland’s his­tory was almost oblit­er­ated during World War II. So Marek now spends a good deal of his time talk­ing about his family’s time in Warsaw during the Nazi occu­pa­tion to groups like ours and par­tic­u­larly school chil­dren.

Marek’s father, Witold Szablewski, was a tool maker, set­tling in Sheffield after the war

Witold Szablewski

and seen here cyc­ling with a friend in Warsaw before the Ghetto was estab­lished (fig 2)

A younger Witold Szablewski on the right

The build­ing in the back­ground is the only pre-war build­ing left in that street, a vivid example of the whole­sale anni­hil­a­tion of the city by the Nazis.

Witold Szablewski returned to the rebuilt city in 2004 as a hero in recog­ni­tion of his role in the Warsaw Uprising and in remem­brance of the thou­sands of Poles whose lives were lost.

Poland’s tur­bu­lent his­tory is also rep­res­en­ted by a series of maps of its ever-changing bor­ders from war­fare.

Reference: Norman Davies “God’s Playground Vol 1 Clarendon Press Oxford 1989

The absence of black (upper right) indic­ates loss of Poland’s sov­er­eignty in 1791–1807, 1874–1918, 1939–45 by Prussia, Russia and Austro-Hungary respect­ively.

Grandfather Stefan seen here upper cent­ral

was a printer and trade uni­on­ist, arres­ted by the Russian author­it­ies on mul­tiple occa­sions for organ­ising strikes, and spend­ing time in Tsarist pris­ons. He had a Russian wife and was con­scrip­ted into the Army. Captured by the Germans, he escaped from Lamsdorf (later StalagVIIIB) and fought in the Polish upris­ing which led to inde­pend­ence, by which time his Russian wife and child had dis­ap­peared. He filed for divorce.

He became a police­man, remar­ried and Marek’s father was born to his second wife, who died a few years later

His Grandfather’s reac­tion­ary beha­viour overtly tempered after he became a detect­ive. He then mar­ried a Jewess, and was work­ing at the Škoda fact­ory in the mid-1930s, prob­ably also under­cover when cor­rup­tion in the com­pany was rife, for instance, issu­ing false qual­ity cer­ti­fic­ates.

He then man­aged blocks of flats claim­ing that he lost his police job “because his wife was Jewish”.

Marek’s father, Witold, became an appren­tice tool maker in spe­cial­ist sur­gical equip­ment in the Ghetto. During the occu­pa­tion, the family house was exchanged to one out­side the Ghetto wall. He had to travel in and out every day to work but often car­ried money, obtained by selling con­tra­band, into the Ghetto.

Jews were expec­ted to walk in the gutter if a Nazi passed by, schools were shut, only a basic edu­ca­tion was avail­able, Jewish bank accounts were frozen, and Chopin was banned. Life was very dif­fi­cult and viol­ent. For instance a state­ment in a 1940 issue of Völkischer Beobachter, the Nazi news­pa­per; “In Prague, big red posters were put up on which one could read that seven Czechs had been shot today….  if I had to put up a poster for every seven Poles shot, the forests of Poland would not be suf­fi­cient to man­u­fac­ture the paper”.

The Ghetto was large with an area of 1.5 square miles and 300,000 Jews within. Enclosure walls across tram tracks had “typhoid” notices to keep people out. It was com­pletely des­troyed by the Nazis at the end of the war as the Russians’ moved in.

This pic­ture shows Josef Blösche, the Warsaw SS-Rottenführer, (with the machine gun) round­ing up Jews during the Uprising. He was nick­named Frankenstein because of his cruelty and he was sub­sequently executed for war crimes.

Marek’s father, who was not car­ry­ing Jewish papers him­self, was sworn into the Resistance. As a keen pho­to­grapher, he recor­ded troop move­ments. At one point he was arres­ted by the Gestapo with a gun to his head but bluffed his way free and lying that he had no know­ledge of his Jewish mother’s where­abouts. On another occa­sion he was car­ry­ing a hidden mes­sage for the Leader of the Jewish Council, when the offices were raided by the Gestapo. He was lent a Star of David arm­band to evade cap­ture within the Ghetto.

Witold gave Stefan’s daughter’s (Russian) birth cer­ti­fic­ate to his Jewish wife, together with its Nazi tax stamps. She was then able to mas­quer­ade as his own daugh­ter as a non-Jewess.

With the help of a local his­tor­ian, after return­ing to Poland, Marek found the ruin of a gues­t­house run by Carmen Achmarańska, and where his Jewish step-grandmother had worked during the occu­pa­tion. It was a favour­ite Nazi water­ing hole. They deman­ded to stay the night. She evac­u­ated the guest house, and was accused of being Jewish, which she denied. She was to be taken to Warsaw 15km away but was shot in the head on the way. The locals were instruc­ted to leave her in the ditch as a warn­ing. She had saved so many lives. The ‘Carmencita’ guest house was burned down in the 1950s.

At the end of the occu­pa­tion in August-October 1944, after the Warsaw Uprising in which Witold took part, there was sys­tem­atic destruc­tion by the Nazis as the Russians moved in. No more than 1000 people remained in the ruins of the city, left hidden under rubble in cel­lars when the city was lib­er­ated by the Red Army in January of 1945.

During the Uprising, German pris­on­ers were extrac­ted from the cel­lars of the tele­phone exchange in Warsaw. According to Marek’s father, women miners dug their way into the build­ing to allow the res­ist­ance fight­ers access, as they were smal­ler and could gain access more easily. His father was heav­ily involved in the Uprising which res­ul­ted in 250000 deaths. The Nazis plundered much art work and other valu­ables, scorch­ing the city before the Red Army moved in. It has now been beau­ti­fully restored to its ori­ginal state in the old town.

At the end of the Uprising, Witold was taken pris­oner and trans­ferred to Germany as a POW, like his Father in Lamsdorf.  His par­ents and half-sister were taken to Berlin as slave labour­ers for the build­ing of Berlin’s Templehof air­port. He came to Hardwick Hall after the war and was employed at Gilbow Tools, Bridge Street Sheffield, and then at W.Tyzack Sons and Turner Ltd of Little London Road in Heeley.

Further recom­men­ded read­ing and pod­cast:

9780131719187: Conversations with an Executioner …

East West Street by Philippe Sands | Waterstones

Marek’s report for the Winston Churchill Memorial Trust:

Marek’s recent pod­cast for Holocaust Memorial Day:

Research into Neurology: Bedside to Lab and Back Again — Nick Verber — 2nd Nov 2020

Nick Verber is a research regis­trar work­ing for his PhD at the Sheffield Institute for Translational Neuroscience Institute (SITraN), University of Sheffield. He gave an excel­lent talk, very suc­cess­fully over­com­ing the tempta­tion of many medics to litter their lec­tures with clin­ical jargon. It was clearly delivered and easily fol­lowed by a large Zoom gath­er­ing of 44 Probus mem­bers.

Although there is a long way to go before there is a cure for motor neuron dis­ease (MND), the Institute here in Sheffield, led by Dame Prof Pamela Shaw, is a world leader in clin­ical and sci­entific research into this and other chal­len­ging and dis­tress­ing con­di­tions.

Nick began with a typ­ical case his­tory which illus­trated the pro­gress­ive nature of MND over a two year period, although there is a great deal of vari­ation in the rate of pro­gres­sion from patient to patient. MND is cruel to patients, rel­at­ives and their friends. It affects all vol­un­tary muscles through­out the body and the case his­tory illus­trated how it pro­gressed from minor weak­ness of the limbs to slurred speech, dif­fi­culty in swal­low­ing which can result in saliva, food and drink going down into the lungs, and breath­ing prob­lems.

Cause of MND

This is com­plic­ated and not fully under­stood. The vast number of nerves con­trolling vol­un­tary muscles become dam­aged and cease to func­tion prop­erly (in con­trast to sens­ory nerves bring­ing sig­nals to the brain about touch, smell, sight, pain etc. and to auto­nomic nerves which con­trol the gut, bowels, water­works and sexual func­tion, all of which remain unaf­fected in MND).

Dr Weaver’s amaz­ing dis­sec­tion — for details see last para­graph

These motor nerves carry sig­nals from the brain to muscles involved with move­ment, pos­ture, speech, swal­low­ing, laugh­ing, and coordin­a­tion of eye move­ments. Eye and facial move­ments are affected much later. Poor strength in the head and neck leads to deformed pos­ture, as seen in the famil­iar wheel­chair pos­ture of Stephen Hawking.

Stephen Hawking. Note the effect of wast­ing of head and neck muscles and fail­ure to sup­port the head

As muscles pro­gress­ively weaken, mental fac­ulties usu­ally remain uncom­prom­ised, caus­ing immense dis­tress and frus­tra­tion. But patients are often prag­matic and pos­it­ive, and are keen to par­ti­cip­ate in, and raise funds for, research.


MND is rel­at­ively rare, with 5000 people having the con­di­tion in the UK. It has the same life­time risk as the more common mul­tiple scler­osis (MS), but there are sub­stan­tially fewer people with MND due to the poor life expect­ancy.


Successful treat­ment is indi­vidu­al­ised and patient focussed, led by a team of spe­cial­ists, nurses, physio­ther­ap­ists, dieti­cians etc. who make the dia­gnosis by clin­ical exam­in­a­tion and invest­ig­a­tion with blood tests, brain MRI, lumbar punc­ture. Treatment centres around indi­vidu­al­ised mul­tidiscip­lin­ary care with pro­vi­sion of social, psy­cho­lo­gical and diet­ary sup­port.

Medication has lim­ited use­ful­ness but Riluzole may slow nerve deteri­or­a­tion. Other inter­ven­tions include diet­ary sup­ple­ments, homo­gen­ised food, gast­rostomy (feed­ing tube inser­ted through the abdom­inal wall into the stom­ach), physio­ther­apy, splints, highly soph­ist­ic­ated wheel­chairs, assisted vent­il­a­tion, occu­pa­tional ther­apy, mobil­ity and cut­lery aids.

Mobility and Cutlery aids

Speech and lan­guage ther­apy is import­ant, and voice bank­ing is avail­able. The inab­il­ity to swal­low saliva (nor­mally 500ml per day) and drool­ing is dis­tress­ing and helped by simple med­ic­a­tion. Approximation of voice with regional accents has recently become pos­sible, over­com­ing to some extent the imper­sonal Dalek sound of the com­puter. Communication prob­lems as speech and motor func­tion decline can be addressed by eye sig­nals facil­it­at­ing com­puter typing.

The main aim of treat­ment and long-term mon­it­or­ing is to allow the patient to retain inde­pend­ence and qual­ity of life.


Nick touched on how MND research is con­duc­ted, using bio­mark­ers

Biomarker research

to assess change in patient con­di­tion, with the aim of provid­ing evid­ence to guide appro­pri­ate treat­ment. Blood tests, nerve con­duc­tion stud­ies, MRI and con­stant mon­it­or­ing of dis­ease are all part of this pro­cess, and are par­tic­u­larly import­ant for assess­ing pro­gress during clin­ical trials

Research is expens­ive. Identifying a useful bio­marker is cru­cial for attract­ing research fund­ing. Charitable fund­ing is helped by high pro­file patients such as Doddy Weir and Rob Burrows who make a pos­it­ive con­tri­bu­tion towards dis­ease treat­ment through research.

MND com­prises sub­groups of patients with sim­ilar but dis­tinct dis­ease pro­files. One research aim in Sheffield is to improve defin­i­tion of these sub­groups in order to improve their treat­ment and avoid any inter­ven­tion found not to work. Some bio­mark­ers differ between MND patients, or between patients and healthy volun­teers.

Skin biopsies are simple, quick, pain­less (fol­low­ing local anaes­thetic admin­is­tra­tion) and read­ily access­ible (with patient con­sent). Fibroblasts are present within them. These are imma­ture cells with mat­ur­a­tion poten­tial to develop new skin or scar tissue (in the case of trauma). Another research strategy in Sheffield is to give genetic inform­a­tion to these fibro­blasts to con­vert them to nerve tissue in a labor­at­ory set­ting. This over­comes a major prob­lem in neur­o­lo­gical research of being unable to access live brain or nerve tissue for exper­i­ment­a­tion.

Nick con­cluded by giving his grat­it­ude to the patients and volun­teers that have donated their time and samples to his research.

If anyone has any interest in volun­teer­ing for research, then please get in touch via his email address at the bottom.


Couldn’t resist this one! Dr Weaver’s amaz­ing dis­sec­tion of Harriet Cole’s nervous system (its huge com­plex­ity is illus­trated by the fact it took from 1888 to 1893 to com­plete the dis­sec­tion, which can still be seen in Philadelphia) (Barton M. The Nervous System of Harriet Cole. Past Medical History. Aug 18, 2018)

Correspondence address:

Those of you who were impressed by the work that Nick and his col­leagues are research­ing can make a dif­fer­ence by donat­ing by copy­ing and paste this into your search engine.




How the Internet Changed the World — Past Present Future — Peter Ivey 5th October 2020

Peter Ivey gave a suc­cinct over­view to a Zoom record of 45 mem­bers on how the inter­net works, and a very useful talk as most like me were fairly clue­less; bits, bytes, HTML, 5G are famil­iar words ban­died around but never quite sure exactly what they all mean.

Peter’s back­ground includes a phys­ics degree at Bristol, BT labs, chair in Electronics and Electronic Engineering in Sheffield, then his own com­pany con­sult­ing on micro­chips.

The inter­net concept began in 1960 when JCR Licklider envis­aged a system of massive inform­a­tion stor­age and retrieval shared by centres and indi­vidual users.

JCR Licklider

At around the same time, Paul Baran (RAND Organisation) poin­ted out the vul­ner­ab­il­ity of US Government com­mu­nic­a­tions and pro­posed a decent­ral­ised net­work that would solve the prob­lem.

Paul Baran

These ideas led in 1969 to the first internet-like net­work (the Advanced Research Projects Agency net­work – ARPAnet), which was developed by Leonard Kleinrock at UCLA, and others, for shar­ing data between uni­ver­sit­ies in California and Utah for research.

Leonard Kleinrock

By 1973 ARPANET had expan­ded across the USA, and by 1975 to London., From this base the net­work has expan­ded across the UK and sub­sequently it has become a huge net­work extend­ing right across the World.

In 1989 Tim Berners-Lee, the inventor of the World Wide Web (www), was work­ing at CERN and was frus­trated by his dif­fi­culty in access­ing the inform­a­tion he needed. He cre­ated a new com­puter lan­guage HTML (Hypertext Markup Language) which remains the stand­ard format of most web pages today. Hypertext allows you to get a doc­u­ment by click­ing on a coded word or phrase. He also developed the tech­no­logy for trans­fer of data across the web; HTTP (Hypertext Transfer Protocol), URLs (web addresses), a web browser and web server soft­ware. He pub­lished the first ever web­site which is still avail­able on the inter­net.

CERN res­isted the tempta­tion to patent, with amaz­ing foresight made the WWW public domain and widely avail­able so it could develop and expand as rap­idly as pos­sible.

The first web browser to become pop­u­lar with the gen­eral public was MOSAIC in 1993. TimBL was knighted in 2004.

Tim Berners Lee

WWW is soft­ware and a means of using the inter­net, which itself is the infra­struc­ture facil­it­at­ing it and mainly hard­ware. There are layers of hard­ware and soft­ware as shown:

The inter­net works by shift­ing binary inform­a­tion. Basic require­ments are a machine plus elec­tri­city and a means to send and receive inform­a­tion. A bit con­tains a single binary value of 0 or 1. Other than defin­ing “True” and “False” it has little other use. 8-group clusters of bits are “bytes”. At least one mil­lion bytes per second are required, for example, to down­load a song and achieved by increas­ing the band width for faster down­load. All com­mu­nic­a­tions over the inter­net  are “splintered” into pack­ets which can be routed along dif­fer­ent chan­nels, then recom­piled into the cor­rect order at the receiv­ing end

To com­mu­nic­ate over long dis­tances light beams are trans­mit­ted via fibre-optic cables, which can send mul­tiple bytes sim­ul­tan­eously at the speed of light with very little signal loss. Radio sig­nals are cheaper than fibre-optics, so 1s and 0s can be con­ver­ted into radio waves by WiFi for con­ver­sion back to fibre-optic and/or copper cable at the receiver end.

The inter­net is vast, with an aver­age of 7 con­nec­ted devices for every human in the world e.g. phone, smart TVs, Sky boxes, Alexa, routers. Telehouse North is one of four data centres in London dis­trib­ut­ing to the whole of the UK and con­tains a huge net­work of optical cables, tidy in front, chaos behind.

Global net­works are con­nec­ted both by sub­mar­ine cables and satel­lites.

If the unthink­able happened and the inter­net went down, it would be impossible to return to the pre-internet days of the 1960s.

Mobiles wouldn’t work, land­lines would be swamped, traffic lights would seize, hos­pital data couldn’t be accessed, cash machines and credit cards would stop, shops would run out of stock and, heaven forbid, Amazon would fail!

It would be an extremely unlikely event in peace­time but is a poten­tial threat in war. Cyberwarfare is a real­ity: the Middle East and India in 2008, Stuxnet worm in 2010, and ter­ror­ism e.g. sab­ot­age of under­sea cables, satel­lite attack but also acci­dent­ally by solar flares.

The “Internet of Things” (IOT) is a hot topic and defined as “the inter­con­nec­tion via the inter­net of com­put­ing devices embed­ded in every­day objects, enabling them to send and receive data”. Examples are remote con­trol of cent­ral heat­ing, mon­it­or­ing chil­dren, pulse oxi­metry, Alexa, trans­port, driver­less cars, logist­ics, agri­cul­ture, indus­trial util­it­ies and smart cities (e.g. park­ing). The IOT is on the way to match­ing the import­ance of inter­net com­mu­nic­a­tion and inform­a­tion e.g. WhatsApp, Google.

5th Generation Cellular will make a massive dif­fer­ence. Peter was def­in­itely not a fan of Huawei. 5G net­works are cel­lu­lar. The ser­vice area is split into small geo­graph­ical areas called cells, access­ible every­where. Devices are con­nec­ted to the inter­net and phone net­work by radio waves through an antenna in the cell, with the bene­fit of greater band­width and much higher down­load speeds. The all too famil­iar 4G video buf­fer­ing on Zoom or Facetime will become a thing of the past.

The Aberfan Disaster of 1966 — Prof Dave Petley — 13 July 2020

Dave Petley gave a superb talk to 41 mem­bers, guests, and an unknown number of wives and girl­friends. It was the second highly suc­cess­ful Probus Zoom present­a­tion since COVID-19 lock­down (thanks to Peter, Graham, Richard and Jacko).

Dave is Vice President for Research and Innovation, University of Sheffield. His research focus is inter­na­tional land­slide mech­an­isms and he advises the Hong Kong Government, blogs with the American Geophysical Union and is a Council member of the Royal Geographical Society. He has a great gift for put­ting over dif­fi­cult con­cepts clearly and con­cisely.

There were seven large spoil tips rising up the hill­side and close to the vil­lage of Aberfan, where 116 chil­dren at Pantglas school and 28 adults lost their lives in the infam­ous land­slide of the morn­ing of 21 October 1966 (Fig 1).

Fig 1 Aberfan land­slide 1966

A prim­it­ive rope­way led to a crane at the top, where there had been loose tip­ping for sev­eral years. The tip­ping gang (Fig 2) arrived at the top at 7.30am and found it had sub­sided overnight.

Fig 2 Ropeway and tip­ping gang on the spoil heap

Finding that the tele­phone to the pit below wasn’t work­ing, one of gang walked down to raise the alarm. The crane driver stayed at the top and saw its tip move again, but rising up ini­tially. The solid mass, as it broke free, rotated and “bull­dozed” ahead, caus­ing the ini­tial rise then the down­hill slide. Rotation pulled away solid blocks which then frag­men­ted into a 40000 ton flow onto the vil­lage

Landslides result from a grav­it­a­tional effect on loose spoil, sat­ur­ated by under­ly­ing nat­ural springs within weak gla­cial depos­its. Solid spoil con­verts to a flow of water, sludge and debris, and a rota­tional slide between loose spoil, gla­cial depos­its and under­ly­ing solid bed­rock occurs (Fig 3).

Fig 3 Mechanics of land­slide form­a­tion

The NCB knew of the Aberfan springs (Fig 4), making no earlier attempt to divert the water and fail­ing to anti­cip­ate, mon­itor and rec­tify

Fig 4 Pre-spoil heap topo­graphy of Aberfan and adja­cent hill­side with the springs circled.

They were aware of sim­ilar tips with land­slide poten­tial. Furthermore, uncon­trolled tip­ping on top of loose layers pro­gress­ively weakened the base to facil­it­ate a slide. There were earlier land­slides in the area at Abercynon (1939), Aberfan (1944 and 1963), and Rhondda (1965). The NCB, nation­al­ised in 1946 and headed by Lord Robens, chose to ignore the danger.

The school was inund­ated and the chil­dren at the rear of the school had no chance. Classrooms at the front remained intact and some sur­vived. Parents, many of them miners, attemp­ted to rescue their own chil­dren and others before the more formal rescue effort could begin.

The Tribunal was con­duc­ted by Lord Justice Edmund Davies, who had sen­tenced the Great Train Robbers. He was highly crit­ical of the NCB, in denial until day 65, but par­tic­u­larly its chair­man Lord Robens, whose invest­it­ure at the University of Surrey was coin­cid­ent­ally and cyn­ic­ally on the night of the dis­aster. He chose not to go to Aberfan. However he even­tu­ally made amends by set­ting up the Health and Safety Executive, a world leader.

Removal of tips was recom­men­ded after the Tribunal but the NCB pleaded it would lead to bank­ruptcy. £150,000 was cov­ertly sequestered (!) from the £1m+ dis­aster fund by the NCB. This was even­tu­ally repaid into the dis­aster fund by the Blair Government, but without interest, until Gordon Brown finally repaid in full. Compensation was capped at £500 for each family, Lord Robens claim­ing that they “wouldn’t be able to cope with a larger sum”.

There was another land­slide at Tylorstown in February 2020, due to rota­tional spoil heap fail­ure. Spoil heaps now have mixed own­er­ship and are not neces­sar­ily well-monitored. Degradation and cli­mate change is renew­ing interest in future poten­tial land­slides in Wales.

Landslides are a major prob­lem around the world. Loss of life is rising with time, con­firmed by evid­ence from Dave Petley’s own data col­lec­tion from 2004. Tibet, Brazil and recently Myanmar have had dis­astrous rota­tional land­slides, in the latter case pre­cip­it­ated by unem­ployed jade miners scav­en­ging and dis­turb­ing spoil heaps.

It was a sur­prise to learn there is no book writ­ten on the Aberfan dis­aster, des­pite the emo­tional memor­ies linger­ing on and a detailed sequence in Netflix series “The Crown”. Dave’s retire­ment pro­ject maybe?

Those inter­ested in more of Dave’s work can access:

Twitter: @davepetley   Blo:

Beware the cliffs!