Photochemical Smog The brownish shroud

We can survive without food for several days, without water for a few days, but we cannot survive more than a few minutes without air. Yet we are altering the chemical make-up of air via rampant emissions of gaseous and particulate matters. The pollutants vented into the atmosphere come from a number of different sources natural and man-made. Among the man-made sources, most harmful are the effluents from vehicles and emissions from industries. They are precursors to the formation of smog, a term coined to describe a mixture of smoke and fog.
Smog is produced through a complex set of photochemical reactions involving particulate matter (dust, soot, etc) and various gases nitrogen oxides, water vapor, carbon monoxide, and carbon dioxide which come out through the exhaust system of a vehicle. They react in the presence of sunlight to produce a witch's brew of virulent pollutants. Among some of the worse are formaldehyde, peroxyacyl nitrate (PAN), and acrolein. Furthermore, ozone is formed at the ground-level through chemical reactions involving unburned hydrocarbons in gasoline, volatile organic compounds, various oxides of nitrogen, and sunlight. The net result is a brownish orange shroud of air pollution called photochemical smog. In addition, smog in industrial towns forms when smoke and sulfur emissions from burning fossil fuels combine with fog. Smog occurs more frequently in communities situated in valleys with surrounding hills and mountains where there is less air circulation and more accumulation of pollutants in the air.
Ozone is one of the most prevalent chemicals in smog. Problematic ozone levels occur mostly on hot summer afternoons when there is little wind and temperatures soar above 30 degrees Centigrade. Effects of ozone are primarily health related. Lungs are ozone's primary target. It aggravates respiratory diseases, particularly asthma, emphysema, and chronic bronchitis. When inhaled, ozone can inflame pulmonary membranes causing significant temporary reduction in lung capacity, from 15 to 20 percent. Adults with respiratory diseases are most susceptible to the adverse effects of ozone. Even healthy adults engaged in strenuous outdoor activities like jogging, gardening, manual labor, etc., will suffer from ozone-related health effects. Ozone can also impair our immune system.
In tandem with ozone, the inherent toxicity in smog can cause chest pains, coughing, throat irritation, and shortness of breath. In the worst case scenario, it may contribute to lung cancer. Formaldehyde, a component of smog, is a colorless gas with pungent smell. It is toxic and will cause burning sensations in the eyes, nose, and throat. The PANs are extremely potent oxidant. They are irritating and harmful. They act like tear gas and irritate the skin, eyes, and nasal passages. The other component of smog, acrolein, is a colorless liquid with an acrid smell. It is a strong irritant for the eyes. Unfortunately, human body has very little defense against these pernicious effects of smog.
Children with asthma are especially vulnerable to the harmful effects of ozone and smog alike. Because of their physiology, they are much more likely than adults to develop smog-related lung damage. Even healthy children are at risk because their respiratory systems are still in the developmental stage.
To make a bad situation worse, smog remains under siege for days if it is accompanied by temperature inversion (TDS, 8 January 2013). We witnessed it earlier this month when major parts of China were trapped in a toxic blanket of smog leaving the citizens literally breathless. Scenes of Chinese cities smothered by smog are a disturbing reminder of the Great London Smog of 1952 which killed over 4,000 people. Ironically, smog-related problems are non-local. The pollutants in smog drift in the wind and can travel to faraway places making the smog in those places more severe.
For many years we viewed pollution as a sign of progress. Today, pollution is seen as signs of failed technologies. The “airpocalypse” in China is clear evidence our atmosphere is too finite to absorb the pollutants dumped into it. Also, it is disquieting to note that except for our lungs, we have run out of place to put them away. If we want to pursue a reasonably healthful existence, we have to live by the maxim “solution to pollution is dilution.” The air we breathe should not make us cough.
Next time you see the setting Sun painting the sky pink and orange, remember it is smog which made the colors so brilliant. There is an ugly story “behind every pretty picture.”

8 fake Rab men held for looting Tk 1cr

Detective Branch of police in an overnight drive on Friday arrested eight people on charge of looting Tk 1.08 crore of a garment factory, identifying themselves as members of Rapid Action Battalion.
Police recovered Tk 40.54 lakh of the looted money and seized a private car during the drive conducted in Dhaka, Gazipur and Tangail.
Masudur Rahman, deputy commissioner of Dhaka Metropolitan Police Media Centre, told reporters while addressing a press briefing at the media centre on Saturday.
The arrestees are Md Tohinur Islam, 35, Arifuzzaman Khan, 35, Abu Sayeed, 35, Md Selim, 32, Shajahan, 32, Kabir Hossain, 33, Bibhash Mandal, 35, Akhtaruzzaman Liton, 26,
The DC said three staff of a garment factory of Azmat Group withdrew Tk 1.08 crore from a local bank on January 10.
As they were returning to the factory located at Ashulia, the gang intercepted their car identifying themselves as Rab members, he said.
Later, they tied up the staff and took away the money, he added.

US congressional delegation due today

A four-member US congressional delegation, led by Jack Kingston, arrives in Dhaka on Saturday on a two-day visit to discuss bilateral issues, including GSP facility.
The other members of the delegation are Scott Tipton, Adam Schiff and Ed Whitfield.
During their stay in Bangladesh, the delegation members will meet Prime Minister Sheikh Hasina, Foreign Minister Dipu Moni, and visit a number of garment factories in the city, officials said.
Meanwhile, Bangladeshi Ambassador in Washington Akramul Quader met congressmen separately and handed over a document demanding continuation of the Generalised System of Preferences (GSP) facility for Bangladeshi products in the US market to maintain the trade potential with the US.
On January 8, the US Trade Representative (USTR) office sought public comments from the stakeholders by January 31 on the possible withdrawal, suspension or limitation of Bangladesh’s duty-free benefits under the GSP.
“The GSP subcommittee is seeking public comments on the effect of a withdrawal, suspension, or limitation of GSP benefits on products imported into the United States from Bangladesh,” said a notice of the Washington-based US Trade Representative.
Some of the members of the US congress had assured that they would take up Bangladesh’s GSP facility issue at the appropriate level of the US authorities so that it could be resolved taking Bangladesh’s best interest into account.

21 get death sentence for Egypt football violence

An Egyptian court has sentenced to death 21 defendants over clashes between rival football fans in which 74 people were killed last February.
The riots began after a league game at Port Said stadium between local side al-Masry and Cairo club al-Ahly.
The violence - Egypt's worst football disaster - sparked riots in Cairo during which a further 16 people died.
The sentences came after a day of clashes between security forces and supporters of the secular opposition.
Hundreds of thousands took to the streets across Egypt to mark the second anniversary of the revolution that ousted ex-President Hosni Mubarak and voice their opposition to Islamist President Mohammed Morsi.
At least seven people were killed in Friday's unrest.
Last year's football riots led to the suspension of the league.
It began when al-Masry fans invaded the pitch, hurling stones and fireworks at the visitors.
At the time some fans - who said security forces appeared to do little to prevent the clashes - accused supporters of toppled President Hosni Mubarak of instigating the incident.
Seventy-three people, including policemen, were tried.
The judge said he would announce the verdict for the remaining 52 defendants on 9 March.

Indonesian authorities battle floods in capital

Authorities were working Friday to repair a dike that collapsed amid torrential rains that have swamped the Indonesian capital, while thousands of police and soldiers worked to help victims of the flooding that has taken nine lives.
Police deployed at least 40 rubber boats, along with those from the army, to help evacuate or bring supplies to people still trapped by the floodwaters that have inundated much of the city of 14 million people since Wednesday, said Jakarta Police Spokesman Col Rikwanto. Elsewhere, hundreds of soldiers were deployed to repair a collapsed canal dike that let floodwater pour into parts of downtown Jakarta.
Rikwanto said the current death toll of nine did not include three people who were reportedly swept into the basement of a building in central Jakarta, where a search was still underway.
The floods are the most widespread to hit the city in recent memory. Few areas were spared, from wealthy suburbs to riverside slums and gleaming downtown business blocks. Offices and schools were deserted and traffic ground to a halt. The international airport was operating normally, but travellers were finding it hard to get there.
"This is horrible," said Yanitha Damayanti, a bank teller stranded downtown. "For the first time in my life, downtown Jakarta has flooded."
The city has long been prone to floods, but successive governments have done little to mitigate the threat. Heavy downpours Wednesday and Thursday added pressure to rivers already swollen by a long monsoon season.
Deforestation in the hills to the south of the city, chaotic planning and the rubbish that clogs the hundreds of rivers and waterways that crisscross the city are some of the factors behind the floods. The city's vulnerability exposes the country's poor infrastructure even as it has posted impressive economic growth in recent years.
On Thursday President Susilo Bambang Yudhoyono had to stand in water up to his shins — his trousers rolled up — at the palace waiting for the arrival of Argentina's leader on a state visit. The president then used a rubber boat to inspect some parts of the inundated capital.
"I have no problem with the palace being flooded, "Yudhoyono said. "The most important thing is the people are protected."
In some places, water levels were up to 2 meters (6 1/2 feet) high. Seen from above, the main road through the heart of the city resembled a muddy river. Even as authorities struggled to rescue those trapped and provide them food and shelter, some were thinking of the economic cost.
"This is an extraordinary disaster," said Syamsuddin Basri. "I had to cancel many important business deals."

Eating greens makes people optimistic

People who eat plenty of fruits and vegetables tend to be more optimistic about the future, new research suggests, reports UK-based news portal Mail Online.
Scientists have discovered that optimistic folk have higher levels of plant compounds called carotenoids in their blood
A commonly-known carotenoid is beta-carotene, a pigment found in high levels in orange fruit and green, leafy vegetables.
Previous studies have shown that high blood levels of antioxidants - of which carotenoids are one form - may be a marker of good health.
Antioxidants help keep other molecules in the body from producing free radicals, which can damage cells and contribute to disease.
'Individuals with greater optimism tended to have greater levels of carotenoids such as beta-carotene,' said lead investigator Julia Boehm, of the Harvard School of Public Health.
'This is the first study of its kind to report a relationship between optimism and healthier levels of carotenoid concentrations,' she added.
One theory is that antioxidants might have a de-stressing effect.
The current study evaluated blood concentrations of nine different antioxidants, including carotenoids such as beta-carotene and vitamin E in nearly 1,000 American men and women ages 25 to 74.
Participants filled out a questionnaire about their life attitudes and provided blood samples to the researchers, according to the report in Psychosomatic Medicine.
They also measured the degree of optimism in the same group.
Researchers found that people who were more optimistic had up to a 13 per cent increase in carotenoid concentrations in their blood compared with people who were less optimistic.
The researchers believe that higher levels of fruit and vegetable consumption among more optimistic people may at least partially explain the results.
They found that people who ate two or fewer servings of fruits and vegetables a day were significantly less optimistic than people who ate three or more servings a day.
They added that the relationship between optimism and carotenoid levels was only partially explained by the fact that more optimistic people tended to engage in healthier behaviors such as eating fruits and vegetables and avoiding cigarette smoking.
Last year, scientists at Warwick University found that people who ate seven portions of fruit and vegetable a day are the happiest.
The study found that those who ate around eight portions of fruit and vegetables a day had an average score that was one point higher than people who did not eat any.
The link remained even when people’s exercise levels and overall diet – both of which can influence mood – were accounted for.
Although it is not known exactly how fruit and vegetable improve wellbeing, they contain chemicals known as antioxidants, which are thought to reduce stress levels.
At the time, lead researcher Professor Andrew Oswald said he was 'stunned ' when he looked at the data.
‘We think we’re on to something really important here,' he said. 'However, we don’t really know why this is – whether there is something in the biochemistry of the fruit and vegetable which works inside humans.
‘We know that fruit and vegetable carry a lot of antioxidants and those protect us against attacks on the body. But how that works through into our minds and emotions, researchers have no idea.'
The Department of Health has spent at least £4million on its ‘five a day’ advertising campaign since it was launched in 2003.
In contrast, the French are told to eat ten portions a day, the Canadians between five and ten, and the Japanese 13 portions of vegetables and four pieces of fruit.

Bailey bridge collapses in Patuakhali

A bailey bridge collapsed at Lebukhali Ferry ghat in Patuakhali Friday morning disconnecting tourist spot Kuakata from the other parts of the country.
Long tailbacks were created as few hundred vehicles including busses, trucks and private cars got stranded on both sides of the ferry ghat on Barisal-Kuakata road following the collapse of the bridge, reports our correspondent in Patuakhali.

The bailey bridge collapsed around 4:00am when a electric pole-laden truck was about to get on it, said Kamolendu Mojumder, executive engineer of Pauakhali Roads and Highways Department.
“We are working on emergency basis to repair the bridge to resume the road communication”, he said.
People were requested to use alternative Patuakhali-Mirjaganj-Bakerganj road until the repair work was complete, he added.

Impending solar storm

The end of the 5,126-year long Mayan calendar on December 21, 2012 was interpreted by many as the day Earth would cease to exist. The doomsday of Mayan calendar has come and gone. But the apocalyptic fears for a calamitous end of the world did not materialize. The Earth is still spinning and orbiting the Sun.
However, fears of an Armageddon have been heightened once again after NASA issued a bulletin warning that the Earth could be subjected to a solar storm of biblical proportions this year. If there is a direct hit, the impact could be catastrophic, costing trillions of dollars in damage to our economic and high-tech infrastructures and affecting some hundreds of millions of people. The doomsday believers are once again speculating that fall-out from the ominous solar storm could be the end of our planet.
A solar storm consisting of many solar flares is the most violent form of solar activity. A flare occurs when magnetic energy that has built up in sunspots is suddenly released. First discovered by Galileo in 1610, sunspots are relatively cool, dark floating islands of electromagnetic storms on the surface of the Sun called the photosphere. Near large sunspots, about a hundred flares occur each day. Typical length and width of a flare are 30 and 15 Earths stacked end to end, respectively.
A flare, accompanied by a burst of ultra-high speed protons and electrons, together with X-rays, ultraviolet, and visible radiation, is followed by a colossal amount of coronal mass ejection (CME). The energy packed in a large flare is equivalent to a nuclear explosion magnified a billion-fold! Relax, the entire energy does not reach the Earth; substantial amount is used up in heating the space surrounding the Sun, its corona (a tenuous uppermost layer of the solar atmosphere) and beyond to 100 million degrees Centigrade.
As the flare races toward Earth, its radiation and CME rip through the upper atmosphere and ionize neutral atoms by removing electrons from them. Most CME's take 18 to 30 hours to reach the Earth. Luckily Earth's magnetosphere guards us from the hazards of such outbursts by absorbing the worst of the radiation. Occasionally, charged particles flowing outwards from a CME escape into the solar wind. If the charged solar wind reaches the Earth, electrons in the wind collide with atmospheric atoms and excite them. The atoms quickly de-excite, emitting visible radiation which gives rise to a spectacular display of colors - auroras (borealis or australis) in the sky.
Flares are most common when numerous sunspots are visible on the solar surface. The time interval between waxing and waning of flares, called solar or sunspot cycle is approximately 11 years. The largest solar storm on record occurred in 1859. It was called the Carrington Event, named after the British Astronomer Richard Carrington, the discoverer of solar flares. It bathed "two-thirds of the Earth's skies in a blood-red aurora a night later, and crippled all of global navigation and global communication, such as it was at that time.”
Two recent massive storms that pummeled the Earth are the Great Aurora of March 1989 and the Halloween Sun Storm of October 2003. The “geomagnetic storm” of 1989 blacked out lights for millions of people in Québec, Canada. Its violence marked the prelude to the solar activity cycle that peaked in July 1989. The Halloween storm disabled many satellites and damaged instruments on a Mars orbiter.
Between 2007 and 2009 the number of sunspots was at a minimum and solar activity went into hibernation. There were practically no flares of consequence during this time. The Sun came out of dormancy last year, spewing off numerous powerful flares, but the gigantic one is waiting in the wings for this year.
NASA believes that the size of the impending solar storm will eclipse the Carrington Event. If the storm hits the bull's-eye, it will disrupt everyday life and leave global economy in a bedlam. The energy released by the storm will cripple Earth's technological infrastructure, mess up satellites, radio communications, internet, and navigation signals from GPS satellites, halt aviation and severely damage electric power grids.
So are we going to witness the end of the world this year? The doomsday prophets will once again be disappointed. The thought of a solar Armageddon in 2013 is far-fetched because the thousands of miles thick magnetosphere 40,000 miles above won't fail us. Besides, lot of the CME is faced away from Earth and consequently the danger is lessened. In fact, other than the usual inconveniences caused by solar storms, we will be entertained to a dazzling show of the auroras. Nonetheless, in the future we can expect a monstrous solar storm that would make the Carrington Event look like a rain shower.

The writer is a Professor in the Department of Physics & Engineering Physics, Fordham University, New York.

The Endgame Homing in on the Higgs boson

The Higgs boson cannot be seen or detected directly. Being a heavy particle (about 125 times as heavy as a proton), it decays to lighter particles immediately after being created in a collision. Some of these decay products may decay to yet lighter particles. Depending on the final decay products, a number of techniques have been developed to search for the Higgs. There are five important search channels, with the Higgs decaying into:
two photons (diphoton channel),
two Z bosons, each of which decays into two electrons or two muons (4-lepton channel),
two W bosons, each of which decays into an electron or a muon and a corresponding neutrino (lvlv channel),
two tau leptons, which can decay in various ways (tautau channel),
two bottom quarks, with the Higgs being produced in association with a W or a Z boson (bb channel).
Of these, the first two channels are the most sensitive, in that they provide the cleanest signatures of Higgs-like events. In each of these two channels, a number of events were found that looked very Higgs-like.
But when and how was it decided that a particle had been discovered?
In high-energy physics, a specific quantitative measure is used to determine whether or not a discovery has occurred. This is necessary because, for example, events that are not from Higgs boson decays can look like Higgs decays, thus generating a fake Higgs signal. A particular set of events constitutes a discovery when the probability of these events being fakes is less than about 3 parts in 10 million. This is a very small number, and means that the analyzers are highly confident that what they see is a real signal. This probability is interpreted in terms of a significance: the significance necessary to claim a discovery is 5 sigma.
With the data collected by June 2012, ATLAS found that while the diphoton and 4-lepton channels individually had significances of less than 5 sigma, a combination of the two yielded a significance of 5 sigma. At that point, ATLAS was ready to declare a discovery. Meanwhile, the CMS experiment had been analyzing their own data, and they also found that a combination of the diphoton and 4-lepton channels gave 5 sigma significance. So the ATLAS results were independently confirmed. Moreover, the mass of the Higgs boson measured in each of the two channels by each experiment was around 125 GeV, which strengthened our conviction that we are all seeing the same particle. For comparison, the mass of a proton is a little less than a GeV.
The two experiments announced their discoveries in a heavily attended seminar at CERN on the morning of July 4, 2012. I have written about my emotions and experiences on that day previously in a short article, so I will not repeat them, except to say that this was the event of a lifetime in a very true sense.
Progress since the discovery
The Higgs discovery was not the end of the story by any means, since much remained to be done. For a starter, it is not known for certain that the discovered particle is in fact the Higgs boson predicted by the Standard Model: there are many models of particle physics that go beyond the Standard Model and predict one or more Higgs or Higgs-like particles. To ascertain whether this is the Standard Model Higgs, it has to be observed in all five of the decay modes listed in the previous section.
Since July 2012, a large amount of additional data has been collected, and the search for the Higgs in the lvlv, tautau and bb channels has continued in addition to the two sensitive channels. None of the less sensitive channels is able to discover the Higgs on its own as yet, but some of them show hints of a Higgs signal. With all channels combined, the significance currently stands at 7 sigma, meaning that the probability of the discovery being spurious is 1 part in a trillion!
Another important step is the measurement of the spin and parity quantum numbers of the discovered particle. Any Higgs-like particle must have spin 0, while the Standard Model Higgs must have even parity. These measurements have already started. At this point, it is definitely starting to look like the Standard Model Higgs, or at least a very Standard Model-like Higgs.
What lies ahead…
2012 has been a phenomenal year for us; Higgs search and measurement results using the full 2012 dataset will be presented at major conferences in the spring and summer of 2013. It is expected that these measurements will go a long way toward answering the vital question: is this the Standard Model Higgs?
Notwithstanding, a full closure of the issue will require much more data than we have now. After a two-year break for upgrades, the LHC will start taking data again in 2015, at the substantially higher collision energy of 13 TeV. The event rate will also be higher, leading to a faster accumulation of Higgs-like events. We will be prepared to analyze these events, increase the accuracy of our measurements and explore the Higgs sector in detail.
Throughout all the Higgs excitement, we firmly keep in mind that this is only one of the principal goals of the LHC. High-energy physics at this crossroads faces a number of intriguing questions: What constitutes the so-called Dark Matter? Is SuperSymmetry a fuller explanation of nature than the Standard Model? Are quarks and leptons really elementary particles, or are they composed of something even more fundamental? We will be looking to answer these questions and more as the LHC program continues through the 2010s, the 2020s and possibly the 2030s.

The writer did his undergraduate studies at Yale University, received a PhD in Physics from Harvard University, and is now a postdoctoral researcher with CERN/University of Wisconsin-Madison. He is based at CERN in Geneva, Switzerland.

Toothy Tale Wings and teeth

A newly discovered bird of the dinosaur age, identified from a fossil, had some of the most elaborate teeth ever seen in a bird, scientists say.
What makes it all the more interesting, they add, is that this bird flourished at a time when other bird species had already begun an evolutionary journey toward toothlessness.
"Maybe differences in diet played a part" in explaining the unusual features of the species, said Jingmai O'Connor of the University of Southern California, lead author of a new study on the findings.
Published in the latest issue of the Journal of Vertebrate Paleontology, the analysis suggests the animal, called Sulcavis geeorum, lived on a tough diet that may have included crabs. The researchers believe the teeth of the new specimen greatly increase the known diversity of tooth shape in early birds, and hints at previously unrecognized ecological diversity.
The fossil hails from the early Cretaceous era, an estimated 121-125 million years ago, from what is now Liaoning Province, China. The bird is believed to a member of a lineage known as Enantiornithines, the most numerous birds from the time of the dinosaur.