2020年7月25日 星期六

留聲機(phonograph)亦稱唱機(gramophone)

留聲機(phonograph)亦稱唱機(gramophone),是一種使唱片發出聲音機器
其聲音儲存在以聲學方法在黑膠唱片平面上刻出的弧形刻槽內。聲音振動波形已雕刻、蝕刻、切割或壓印到旋轉圓柱或盤的表面的溝槽裏,稱為「記錄」。為了重新創造聲音,旋轉表面,使用針頭跟蹤凹槽並因此被它振動,可以非常微弱地再現所記錄的聲音。在早期的聲學留聲機中,針頭振動了一個振膜,振膜產生的聲波透過喇叭,或透過聽診器式耳機直接傳播到聽眾的耳朵。
第一個留聲機最早於1877年由美國發明家愛迪生(Thomas Alva Edison,1847-1931年)發明,而第一個使用唱片的留聲機於1888年由德裔美國發明家伯利那(E.Berliner,1851-1929)首先演示。唱片後來逐漸取代了筒式留聲機,因為唱片能比較方便地大量複製,播放時間也比大多數筒形錄音介質長。
***
Usage of terminology is not uniform across the English-speaking world (see below). In more modern usage, the playback device is often called a "turntable", "record player", or "record changer", although each of these terms denote categorically distinct items. When used in conjunction with a mixer as part of a DJ setup, turntables are often colloquially called "decks".[5] In later electric phonographs (more often known since the 1940s as record players or, most recently, turntables[6]), the motions of the stylus are converted into an analogous electrical signal by a transducer, then converted back into sound by a loudspeaker.[7]
Close up of the mechanism of an Edison Amberola, circa 1915
The term phonograph ("sound writing") was derived from the Greek words φωνή (phonē, "sound" or "voice") and γραφή (graphē, "writing"). The similar related terms gramophone (from the Greek γράμμα gramma "letter" and φωνή phōnē "voice") and graphophone have similar root meanings.[8] The roots were already familiar from existing 19th-century words such as photograph ("light writing"), telegraph ("distant writing"), and telephone ("distant sound"). The new term may have been influenced by the existing words phonographic and phonography, which referred to a system of phonetic shorthand; in 1852 The New York Times carried an advertisement for "Professor Webster's phonographic class", and in 1859 the New York State Teachers Association tabled a motion to "employ a phonographic recorder" to record its meetings.
Arguably, any device used to record sound or reproduce recorded sound could be called a type of "phonograph", but in common practice the word has come to mean historic technologies of sound recording, involving audio-frequency modulations of a physical trace or groove. In the late-19th and early-20th centuries, "Phonograph", "Gramophone", "Graphophone", "Zonophone", "Graphonole" and the like were still brand names specific to various makers of sometimes very different (i.e. cylinder and disc) machines; so considerable use was made of the generic term "talking machine", especially in print. "Talking machine" had earlier been used to refer to complicated devices which produced a crude imitation of speech, by simulating the workings of the vocal cords, tongue, and lips – a potential source of confusion both then and now.

John Goodenough, The Enrico Fermi Award 的獎金究竟多少?









"Be enthusiastic about life. Be thankful for life and be thankful to people who like to engage in meaningful dialogue with you."
Happy birthday to Chemistry Laureate John Goodenough, the oldest person to receive a Nobel Prize. He turns 98 today.





**** The Enrico Fermi Award 的獎金究竟多少? Wiki 中/日 vs 英文版不同
Goodenough was a co-recipient of the 2009 Enrico Fermi Award for his work in lithium-ion batteries, alongside Siegfried S. Hecker of Stanford University who had received the award for his work in plutonium metallurgy.[40]


The Enrico Fermi Award is an award honoring scientists of international stature for their lifetime achievement in the development, use, or production of energy. It is administered by the U.S. government's Department of Energy. The recipient receives $50,000, a certificate signed by the President and the Secretary of Energy, and a gold medal featuring the likeness of Enrico Fermi.[1]


古迪納夫是一個2009年恩里科·費米獎的共同獲得者。這個總統大獎是一種美國政府最古老和最負盛名的獎勵,並有一個37.5萬美元的獎金。


恩里科·費米獎(Enrico Fermi Award),是美國政府機構原子能委員會頒發的一項國際獎,於1954年設立,費米去世前成為首位獲獎者,獎金為32萬5千美元恩里科·費米獎每年頒發一次,用來獎勵在核物理有高度成就的傑出人士,候選人由美國全國科學院院士、各科學技術學會的官員投票選出。恩里科·費米獎不授予單一成果,而是以候選人終生的成就做為評價標準,予以獎勵,算是一種終身貢獻獎。

In Vitro Fertilization, IVF

 In Vitro Fertilization, IVF


Nobel Prize


Who else can say that the method of their conception was worthy of a Nobel Prize?
On this day in 1978 the first IVF baby, Louise Brown was born, being held here by Nobel Laureate Robert Edwards, whose research enabled IVF. Although the media referred to Louise Brown as a "test tube baby", her conception actually took place in a petri dish.
A private donation enabled the project to continue after other funding had been withdrawn since Edward’s research grew increasingly controversial. Several bishops and ethicists demanded that the project be stopped, whereas others supported it. Critics considered the research ethically questionable; one of their concerns was that children conceived through IVF might have birth defects. The British Medical Research Council questioned both the safety and the long-term usefulness of infertility treatment and turned down an application for research funding.
Robert Edwards viewed these ethical questions with profound earnestness. However, he considered the risks of IVF to be small and was determined to bring his work to fruition. He was awarded the 2010 Medicine Prize "for the development of in vitro fertilization". Since the birth of Louise Brown, his contributions have helped millions of people bring new life into the world.





Hybrid embryos of northern white rhinos and their cousins from the south may pave the way for the creation of pure northern-white embryos

受精し分裂した卵(胚)を子宮内に移植することを含めて体外受精・胚移植(IVF-ET)(ET; embryo transfer)という。 胚盤胞まで成長させてから子宮内に移植する場合は、IVF-BT(BT; blastocyst transfer)という。

体外受精 - Wikipedia

https://ja.wikipedia.org/wiki/体外受精

英: In Vitro Fertilization, IVF

2020年7月23日 星期四

How Play Energizes Your Kid’s Brain



How Play Energizes Your Kid’s Brain

Scientists have long studied play to gain insights into the developing human mind.
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CreditCredit...By Nick Little


By Cassandra Willyard
July 21, 2020

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Swiss psychologist Jean Piaget, one of the founding fathers of developmental psychology, spent hours each day observing his children as they grew. He recorded his observations in a raft of notebooks. Lore has it that his wife even carried a notebook on her necklace to jot down observations that Piaget himself missed.

One day, in 1925, his 7-month-old daughter, Jacqueline, was playing with a plastic duck in her crib. She tried to grasp it, but the duck slid down behind a fold in the sheet. Jacqueline saw the duck fall, “but as soon as the duck has disappeared — nothing more!” Piaget wrote. She seemed to forget the duck’s existence. Piaget picked up the duck and held it out and, just as Jacqueline was about to grasp it, he moved it “very obviously” under the sheet. But she still didn’t look for it.

This disappearing duck trick didn’t work forever. Piaget observed that babies do begin to hunt for and retrieve hidden toys starting at about 8 months. He saw this understanding that an object you can’t see still exists — what we now call “object permanence” — as a significant achievement (and perhaps why peek-a-boo loses its appeal).


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To the untrained eye, play can seem aimless, repetitive, wild or foolish. But play can offer a window into the developing mind. Piaget viewed certain kinds of play as milestones, signs that a child had reached a new stage of development. Studies conducted over the past few decades suggest play serves a more crucial role. Play can help kids learn, plan and even persevere in the face of adversity.

Do you believe in magic?

Babies start playing almost as soon as they become aware of their surroundings. They even conduct their own tiny science experiments to help them better understand the world. But some research suggests that they might not have to learn everything from scratch, that kids are born with surprisingly sophisticated expectations about how the world should work, like a basic grasp of gravity or math.

“That’s knowledge that has accrued through evolution,” said Lisa Feigenson, Ph.D., a professor of psychological and brain sciences at Johns Hopkins University and co-director of their child development lab. Decades of research have shown that if you present something to babies other than what they’re expecting, they get interested. “You want to figure out, why did I get this wrong?” she said.

Take gravity, for instance. Dr. Feigenson and Aimee Stahl, Ph.D., a psychologist at the College of New Jersey, showed 11-month-old infants toys that behaved in expected ways — a ball that rolled down a ramp and hit a wall — and toys seemingly imbued with a bit of magic, such as a ball that appeared to roll through a solid wall.

Babies paid more attention to the “magic” toys and even preferred them over other new toys. And when the researchers offered babies these magic toys, the infants seemed to understand how they were surprising, banging the wall-traversing ball against their high chair tray to test its solidity.

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The researchers then gave these toys some unique feature. They showed babies that the ball squeaked, for example. Babies who observed the magic ball absorbed this information better than babies who saw a boring old ball that bumped against the wall. When the researchers presented the ball again along with a distracting new toy and played the squeak, the babies still tended to gaze at the ball. These same patterns held when Dr. Feigenson and Dr. Stahl did a modified version of the experiment with 3- to 6-year olds.
Let’s just pretend

As babies become toddlers, their play gets more complex. Instead of simply making objects move through space, they begin to make believe. A banana might become a telephone and a pencil might take flight like an airplane. This penchant for pretend presents a conundrum: Why would kids, who are only just beginning to make sense of the real world, spend time making up new worlds?

One common idea is that, by pretending, children are practicing deciphering others’ emotions and beliefs. But an alternate hypothesis is that pretend play helps kids develop a skill known as counterfactual reasoning.

Adults use this skill to consider events that haven’t occurred and ponder what would happen if they had. For example, what would have happened if I had grabbed my wallet off the dresser before catching a cab to the airport? Mulling over past “what ifs” helps us better plan for the future.

“That’s a very important, very distinctive human ability,” said Alison Gopnik, Ph.D., a developmental psychologist at the University of California, Berkeley. That means separating actual events from possible events and pretend play helps children do that. What would happen if I could use this banana to call my grandma? What if this pencil could take flight?

To investigate this link between pretend play and counterfactual reasoning, Dr. Gopnik and her colleagues gave 3- and 4-year-olds a stuffed monkey, a “birthday machine” and some special blocks called “zandos.” The researcher explained that it was Monkey’s birthday, and told them that they could use the birthday machine to play “Happy Birthday.” To activate the machine, they would have to locate a zando and place it on top. Non-zandos, she said, do not make the machine play “Happy Birthday.” The children then placed the blocks on the birthday machine to determine which block would make the music play and which would not.

Once the children understood the cause-and-effect relationship, the researcher asked them a series of hypothetical questions. “What if this block were not a zando?” And then, “What if this block were a zando; what would happen if we put it on the machine?” About two-thirds of the kids answered correctly.


Then the fun really began. One of Dr. Gopnik’s team members knocked on the door and repossessed the Happy Birthday machine. “Everyone’s very crestfallen,” Dr. Gopnik said. But then the researcher suggested another way to surprise Monkey. She offered up a plain wooden box and asked kids to pretend it was the birthday machine. Then she suggested a different block as a pretend zando. “What will happen if we put this zando on the machine?” the researcher asked. “What if we pretend this isn’t a zando, then what will happen?”

Again, about two-thirds of the kids answered correctly, the same children who performed well in the first experiment. That is, the ones who could imagine hypotheticals that hadn’t occurred were also the best at pretending to operate an imaginary machine with an imaginary zando.

Dr. Gopnik and her colleagues have shown in other experiments that asking kids to pretend before presenting them with hypotheticals improves their performance. These studies suggest that pretend play is a steppingstone to the important adult skill of planning.
The Batman effect

Pretend play might also help kids regulate their emotions and persevere through difficult, tedious or frustrating tasks. In one experiment, researchers at the University of Minnesota put a toy inside a glass lockbox and handed 4- and 6-year-olds a ring of tiny keys. Open the box, they told the kids, and you’ll be able to play with the toy.

They asked a quarter of the children to pretend to be someone else while they completed the task — Batman or an intrepid adventurer like Dora the Explorer. They even offered them props to make them feel more like that character.

Stephanie Carlson, Ph.D., a developmental psychologist at the University of Minnesota who ran the experiment, and her colleagues hoped to get the kids to step outside themselves. They hypothesized that this kind of psychological distancing might help the children better manage their emotions during what turned out to be a frustrating task.

And the kids did get frustrated. In an odd twist, none of the keys actually worked (though the kids did get to play with the toy at the end). The children who pretended to be the hardworking fictional characters stayed calmer. They also spent more time trying to open the box and tried more keys.



This “Batman effect” — coined by Dr. Carlson and her colleagues — was most evident in younger kids and those with poor self-control and working memory. The Batman effect also helped kids persevere when faced with another, more boring, task. It’s a trick that might come in handy when you need your preschooler to help, say, pick up Legos.

For kids, of course, play isn’t about learning or planning or regulating emotions. It’s about having fun. Play may be “evolution’s way of building in an insurance policy” to learn and develop, said Dr. Feigenson. It’s so enjoyable that most kids can’t resist, and along the way they develop the skills they need to succeed as adults.

2020年7月18日 星期六

Magnetometers based on diamonds will make navigation easier

基於鑽石的磁力計將使導航更加輕鬆
This new form of magnetic navigation is so accurate that it might supersede GPS for aerial navigation

2020年7月16日 星期四

Nobel Prize Museum. .Sancar's DNA model pictured, built in 1986, was used as a working tool as well as in his lectures to explain his discovery.

Living cells have DNA molecules that carry an organism's genes. For the organism to live and develop, its DNA cannot change. DNA molecules are not completely stable, and they can be damaged.
In 1983, through studies of bacteria, Aziz Sancar showed how certain protein molecules - repair enzymes - repair DNA damaged by ultraviolet (UV) light. These discoveries have increased our understanding of how the living cell works, the causes of cancer and ageing processes.
Sancar's DNA model pictured, built in 1986, was used as a working tool as well as in his lectures to explain his discovery. It was later donated to the
Nobel Prize Museum
.
In 2015 Sancar shared the Nobel Prize in Chemistry with Tomas Lindahl and Paul Modrich "for mechanistic studies of DNA repair."

2020年7月12日 星期日

Polio: An American Story by David M. Oshinsky《他們應當行走:美國往事之小兒麻痹症 》;兒童期的弱小兒麻痺病毒 (可能療程不完全)可突變成致癱瘓的病毒John Franklin Enders, “Father of Modern Vaccines”









John Franklin Enders, a Yale graduate, is known to many as the “Father of Modern Vaccines” due to his integral role in developing both the polio and measles vaccines. Read the full story on Manuscripts and Archives, Yale University Library page: http://campuspress.yale.edu/mssa/
Access the John Franklin Enders collection here: https://archives.yale.edu/repositories/12/resources/4495……
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Polio: An American Story 








POLIO: AN AMERICAN STORY
by David M. Oshinsky
© 2004 Oxford University Press Inc.
The following excerpt begins on page 282:
Sometimes forgotten amidst these triumphs and controversies are the lives that were affected most by
this devastating disease. Today the word “polio” describes a vaccine to be taken, not a disease to be
feared. “It’s interesting”, a polio survivor observed, “but even with my limp and all my braces I’ve worn
over all the years, people usually don’t have any idea what’s wrong with my legs.” Another survivor
recalled a young neighbor asking him whether his parents practiced “a strange sort of religion” that didn’t
permit vaccination. “To her, and to most others her age,” the man added, “there had always been a polio
vaccine.”
By conservative estimates, there are at least 400,000* survivors of paralytic polio in the United States.
Some recovered much of their muscle function through a process of muscle regeneration whereby
surviving nerve cells developed extra branches, known as axonal sprouts, which reattached themselves
to orphaned muscle fibers. Others endured multiple surgeries to reconstruct a “dropped foot,” realign a
shortened leg, or straighten a badly curved spine – surgeries that required stapling of bones, the
lengthening of tendons, and the fusing of joints. Many still walk with the aid of canes and crutches, wear
a built-up shoe to compensate for a shorter leg, use motorized wheelchairs to move about, or need a
respirator to help them breathe. What polio survivors have always had in common, however, is a drive to
excel in the face of physical disability. Studies have compared them to the hard-driving over-achieving
individuals associated with Type A personality. In the words of one survivor: “We were [taught] to be
tough and gritty. I did what was expected…I needed to have a disciplined life with a no-quit attitude.
That was what worked.”
According to Dr. Lauro Halstead, director of the post-polio program at the National Rehabilitation Hospital
in Washington, D.C., most survivors developed “a special relation to their bodies unknown to able-bodied
persons. They experienced a new mastery over their muscles and movements, an element of
control…that carried over into other aspects of their lives and probably accounts for why so
many…excelled at school and work.” Surveys have shown polio survivors to be better educated than the
general population, with higher incomes and marriage rates as well. “Don’t let any [of us] tell you they
just want to be ‘normal’ like everyone else,” a survivor wrote in a questionnaire, We have to be better than
anyone else just to break even…and that may not be enough.”
Following years of surgery, rehabilitation and exercise, polio survivors came to regard their condition as
stable. They saw polio as a static disease, unlikely to return or worsen with age. But this comforting
assumption was challenged in the 1980’s, as polio survivors began to experience health problems eerily
reminiscent of their earlier ordeal. *(400,000 to 1,000,000 is another figure often used)
The symptoms were alarming: joint pain, sensitivity to cold, difficulties with breathing
and swallowing, progressive muscle weakness, and extreme fatigue. There were so many cases that
polio survivors formed support groups to pool information and alert the medical community to their plight.
Most American doctors of the post-Salk, post-Sabin era had never treated a case of polio. Their
ignorance of the disease, beyond the importance of immunization, was distressing.
In 1984, Dr. Halstead and others organized the first international conference on the delayed effects of
polio. The idea was to increase public awareness and spur medical research. The organizers attached a
handle to these multiple symptoms – Post-Polio Syndrome (PPS). “Without a name there was, in
essence, no disease,” Halstead recalled.” “Having a name -even if imprecise and misleading as to
causation – at least confers an element of credibility.”
In the past two decades, researchers have studied PPS at some length. Most believe that the fatigue and
muscle weakness experienced by so many polio survivors are due to wear and tear on existing nerve
cells – a theory bolstered by the three to four decades it took for these complaints to be voiced. According
to researchers, the motor neurons that survived the initial polio attack and sprouted extra branches have
degenerated over time. Part of this is due to the normal aging process, but a larger part, it appears, is
caused by the heavy demand put on these remaining motor neurons. “It’s as if you had a ten-cylinder car
Page 2 of 2
before you had polio and have a four-cylinder car afterward – a car that has driven just fine for forty years
or more,” a researcher explained. “At some point, the engine is going to break down.”
Though no conclusive diagnostic test yet exists for PPS, the percentage of polio survivors suffering from
progressive muscle weakness and extreme fatigue is estimated to be as high as 50 percent. Moreover,
those who endured the severest cases of polio and made the greatest functional recovery are the most
likely to be affected. Dr Halstead presents himself s an example. Contracting polio as a college student
in 1954, he moved, “from iron lung to wheelchair to foot brace and then to no assistive device at all.”
Though his right arm remained paralyzed, he sped through medical school, took up competitive squash
and mountain climbing, and convinced himself that “polio is behind me. I have finally conquered it.” But
in the early 1990’s, Halstead wrote, “I had begun developing new weakness in my legs. As the weakness
progressed over a period of month, I went from being a full-time walker who jogged up six flights of stairs
for exercise to having to use a motorized scooter full-time at work.” Halstead had no doubts about his
condition. It was the same one he had been diagnosing in other polio survivors for a decade.
The recognition of PPS has had a powerful bonding effect on a group that showed great trouble
acknowledging its past. “Until recently,” a polio survivor noted, “most of us tended to avoid [each] other
and polio help groups. We knew we weren’t physically normal, but if we thought about it at all, we
considered ourselves as inconvenienced, not disabled.” Brought together by common fears and
concerns, polio survivors began to relive the memories they had long suppressed: the splitting headaches
and widening paralysis that signaled the disease, the excruciating spinal tap that confirmed it, the terror of
the isolation ward, the grief-stricken parents, the long separation from family, the multiple surgeries, the
months spend in a body cast, the feeling of helplessness, humiliation, and loss. Dr. Richard Owen, a
polio survivor who founded the Post-Polio Clinic at the Sister Kenny Institute in Minneapolis, recalled that
he and other victims were often treated at teaching hospitals, where, “clad only in little cloth things that
hardly covered us and our embarrassment,” they became perfect subjects for clinical demonstration. “For
many of us,” Owen added, “the acute illness and convalescence was during adolescence with the impact
of polio superimposed on all the usual stresses and strains of growing up. Barriers to building, activities,
opportunities, and associations added to frustration and, in some cases, social isolation of young people
with the residuals of poliomyelitis. Many barriers…were self-imposed. Various coping mechanisms often
covered true feelings of loss. Denial often led to distorted reality.”
Those days are over. The concerns over PPS created a powerful network to deal with physical and
psychological issues facing polio survivors, which in turn fueled a growing disability-rights movement
across the United States. Polio survivors played a key role in lobbying for the passage of the Americans
with Disabilities Act of 1990, which prohibits discrimination against the disabled and requires physical
access to most public spaces. More symbolically, they joined with disability-rights activists to protest a
new memorial for Franklin Delano Roosevelt in Washington, opened by the National Park Service in
1997, which largely ignored the president’s struggle with polio. The park service insisted it was only
reflecting FDR’s own desire to portray himself as able-bodied. “With the country ravaged by the Great
Depression and yearning for strong leadership,” it said, “Roosevelt realized the need to continue this
façade.” But polio survivors wanted Americans to remember him “as both heroic and disabled,” arguing
that his disability had been integral to his character, and an essential part of who he was and what he
accomplished. In the end, the park service reluctantly added a ten-foot statue of Roosevelt seated in his
wheelchair. The concession spoke volumes to those who best understood the late president’s dilemma.
“Our national disability politics has come a long way since the 1930’s,” an activist explained. “Shouldn’t
our national aesthetics now take up the challenge to transform the meaning of disability?




---

Man found to have been shedding virulent strain of polio for 30 years


Weakened form of polio from childhood immunisations lived on in subject’s gut, mutating into a strain which could cause paralysis in the unvaccinated
The polio virus. The British man was found to be carrying a form of the virus which had mutated from the weakened form used in vaccines. Photograph: Dennis Kunkel/Microscopy, Inc.


Emily Mobley

Thursday 27 August 2015 19.00 BSTLast modified on Friday 28 August 201511.42 BST




A British man with an immune deficiency has been shedding a highly virulent, mutant strain of polio virus for nearly 30 years as a result of childhood vaccinations.

The discovery has prompted scientists to warn of other patients who could unwittingly trigger fresh outbreaks of the disease in regions where people are not sufficiently protected against the illness.



Africa's year free of polio is giant step towards eradication

Read more

Researchers analysed more than 100 stool samples from the man and found mutated versions of the polio virus capable of causing paralysis. They believe he has been shedding the mutated strain for 28 years.


The man had a full course of polio vaccinations, which included three doses of weakened live virus at 5, 7 and 12 months, followed by a booster jab when he was about seven years old. He was later diagnosed with a condition that suppresses the immune system, affecting its ability to kill viruses in his gut.


Tests on the viruses found in the man’s stool samples revealed they had mutated from the weakened form used in the vaccines into a more dangerous strain.


People who are fully vaccinated against polio are not at risk, but in countries where routine vaccination is not encouraged, similar immune-deficient patients could potentially start a new polio outbreak.


The man received the older oral polio vaccine (OPV) that contained a weakened form of the virus, and was often given on a sugar cube. In 2004, the UK switched to an inactivated polio vaccine (IPV) which is injected.


The discovery, reported in the journal Plos Pathogens, has implications for health officials who are close to eradicating polio from the three remaining countries where the virus is still circulating: Pakistan, Afghanistan and Nigeria.


Before the disease can be completely wiped out, mutated strains of polio virus derived from vaccines must be tackled. To that end, the World Health Organisation is set to trial a new vaccine next April.


But work still needs to be done to eradicate polio worldwide, and this discovery of a mutated poliovirus in the UK, among others in Slovakia, Finland and Estonia, presents an extra hurdle before the finish line.


“These viruses could potentially cause poliomyelitis in susceptible people, so it is very important to maintain high levels of vaccine coverage,” said Javier Martin of the UK National Institute for Biological Standards and Control.


“We are working on an end-game strategy,” he added.