Mars Likely to Have Enough Oxygen to Support Life: Study

Agencies
October 23, 2018

Oct 23: Salty water just below the surface of Mars could hold enough oxygen to support the kind of microbial life that emerged and flourished on Earth billions of years ago, researchers reported Monday.

In some locations, the amount of oxygen available could even keep alive a primitive, multicellular animal such as a sponge, they reported in the journal Nature Geosciences.

"We discovered that brines" - water with high concentrations of salt - "on Mars can contain enough oxygen for microbes to breathe," said lead author Vlada Stamenkovic, a theoretical physicist at the Jet Propulsion Laboratory in California.

"This fully revolutionises our understanding of the potential for life on Mars, today and in the past," he told AFP.

Up to now, it had been assumed that the trace amounts of oxygen on Mars were insufficient to sustain even microbial life.

"We never thought that oxygen could play a role for life on Mars due to its rarity in the atmosphere, about 0.14 percent," Stamenkovic said.

By comparison, the life-giving gas makes up 21 percent of the air we breathe.

On Earth, aerobic -- that is, oxygen breathing -- life forms evolved together with photosynthesis, which converts CO2 into O2. The gas played a critical role in the emergence of complex life, notable after the so-called Great Oxygenation Event some 2.35 billion years ago.

But our planet also harbours microbes - at the bottom of the ocean, in boiling hotsprings -- that subsist in environments deprived of oxygen.

"That's why -- whenever we thought of life on Mars -- we studied the potential for anaerobic life," Stamenkovic.

Life on Mars?

The new study began with the discovery by NASA's Curiosity Mars rover of manganese oxides, which are chemical compounds that can only be produced with a lot of oxygen.

Curiosity, along with Mars orbiters, also established the presence of brine deposits, with notable variations in the elements they contained.

A high salt content allows for water to remain liquid -- a necessary condition for oxygen to be dissolved - at much lower temperatures, making brines a happy place for microbes.

Depending on the region, season and time of day, temperatures on the Red Planet can vary between minus 195 and 20 degrees Celsius (minus 319 to 68 degrees Fahrenheit).

The researchers devised a first model to describe how oxygen dissolves in salty water at temperatures below freezing.

A second model estimated climate changes on Mars over the last 20 million years, and over the next 10 million years.

Taken together, the calculations showed which regions on the Red Planet are most likely to produce brine-based oxygen, data that could help determine the placement of future probes.

"Oxygen concentrations [on Mars] are orders of magnitude" - several hundred times - "greater than needed by aerobic, or oxygen-breathing - microbes," the study concluded.

"Our results do not imply that there is life on Mars," Stamenkovic cautioned. "But they show that the Martian habitability is affected by the potential of dissolved oxygen."

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News Network
April 28,2020

Los Angeles, Apr 28: People who experience loss of smell as one of the COVID-19 symptoms are likely to have a mild to moderate clinical course of the disease, according to a study which may help health care providers determine which patients require hospitalisation.

The findings, published in the journal International Forum of Allergy & Rhinology, follows an earlier study that validated the loss of smell and taste as indicators of infection with the novel coronavirus, SARS-CoV-2.

According to the scientists from the University of California (UC) San Diego Health in the US, patients who reported loss of smell were 10 times less likely to be hospitalised for COVID-19 compared to those without the symptom.

"One of the immediate challenges for health care providers is to determine how to best treat persons infected by the novel coronavirus," said Carol Yan, first author of the current study and rhinologist from the UC San Diego Health.

"If they display no or mild symptoms, can they return home to self-quarantine or will they likely require hospitalisation? These are crucial questions for hospitals trying to efficiently and effectively allocate finite medical resources," Yan said.

The findings, according to the researchers, suggest that loss of smell may be predictive of a milder clinical course of COVID-19.

"What's notable in the new findings is that it appears that loss of smell may be a predictor that a SARS-CoV-2 infection will not be as severe, and less likely to require hospitalisation," Yan said.

"If an infected person loses that sense, it seems more likely they will experience milder symptoms, barring other underlying risk factors," she added.

Risk factors for COVID-19 previously reported by other studies include age, and underlying medical conditions, such as chronic lung disease, serious heart conditions, diabetes, and obesity.

In the current study, the scientists made a retrospective analysis between March 3 and April 8 including 169 patients who tested positive for COVID-19 at UC San Diego Health.

They assessed olfactory and gustatory data for 128 of the 169 patients, 26 of whom required hospitalisation.

According to the researchers, patients who were hospitalised for COVID-19 treatment were significantly less likely to report anosmia or loss of smell -- 26.9 per cent compared to 66.7 per cent for COVID-19-infected persons treated as outpatients.

Similar percentages were found for loss of taste, known as dysgeusia, they said.

"Patients who reported loss of smell were 10 times less likely to be admitted for COVID-19 compared to those without loss of smell," said study co-author Adam S. DeConde.

"Moreover, anosmia was not associated with any other measures typically related to the decision to admit, suggesting that it's truly an independent factor and may serve as a marker for milder manifestations of Covid-19," DeConde said.

The researchers suspect that the findings hint at some of the physiological characteristics of the infection.

"The site and dosage of the initial viral burden, along with the effectiveness of the host immune response, are all potentially important variables in determining the spread of the virus within a person and, ultimately, the clinical course of the infection," DeConde said.

If the SARS-CoV-2 virus initially concentrates in the nose and upper airway, where it impacts olfactory function, that may result in an infection that is less severe and sudden in onset, decreasing the risk of overwhelming the host immune response, respiratory failure, and hospitalisation, the scientists added.

"This is a hypothesis, but it's also similar to the concept underlying live vaccinations," DeConde explained.

"At low dosage and at a distant site of inoculation, the host can generate an immune response without severe infection," he added.

Loss of smell, according to the study, might also indicate a robust immune response which has been localised to the nasal passages, limiting effects elsewhere in the body.

Citing the limitations of the study, the scientists said they relied upon self-reporting of anosmia from participants, which posed a greater chance of recall bias among patients once they had been diagnosed with COVID-19.

They added that patients with more severe respiratory disease requiring hospitalisation may not be as likely to recognise or recall the loss of smell.

So the researchers said more expansive studies are needed for validating the results.

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News Network
May 30,2020

May 30: Patients undergoing surgery after contracting the novel coronavirus are at an increased risk of postoperative death, according to a new study published in The Lancet journal which may lead to better treatment guidelines for COVID-19.

In the study, the scientists, including those from the University of Birmingham in the UK, examined data from 1,128 patients from 235 hospitals from a total of 24 countries.

Among COVID-19 patients who underwent surgery, they said the death rates approach those of the sickest patients admitted to intensive care after contracting the virus.

The scientists noted that SARS-CoV-2 infected patients who undergo surgery, experience substantially worse postoperative outcomes than would be expected for similar patients who do not have the infection.

According to the study, the 30-day mortality among these patients was nearly 24 per cent.

The researchers noted that mortality was disproportionately high across all subgroups, including those who underwent elective surgery (18.9 per cent), and emergency surgery (25.6 per cent).

Those who underwent minor surgery, such as appendicectomy or hernia repair (16.3 per cent), and major surgery such as hip surgery or for colon cancer also had higher mortality rates (26.9 per cent), the study said.

According to the study, the mortality rates were higher in men versus women, and in patients aged 70 years or over versus those aged under 70 years.

The scientists said in addition to age and sex, risk factors for postoperative death also included having severe pre-existing medical problems, undergoing cancer surgery, undergoing major procedures, and undergoing emergency surgery.

"We would normally expect mortality for patients having minor or elective surgery to be under 1 per cent, but our study suggests that in SARS-CoV-2 patients these mortality rates are much higher in both minor surgery (16.3%) and elective surgery (18.9%)," said study co-author Aneel Bhangu from the University of Birmingham.

Bhangu said these mortality rates are greater than those reported for even the highest-risk patients before the pandemic.

Citing an example from the 2019 UK National Emergency Laparotomy Audit report, he said the 30-day mortality was 16.9 per cent in the highest-risk patients.

Based on an earlier study across 58 countries, Bhangu said the 30-day mortality was 14.9 per cent in patients undergoing high-risk emergency surgery.

"We recommend that thresholds for surgery during the SARS-CoV-2 pandemic should be raised compared to normal practice," he said.

"For example, men aged 70 years and over undergoing emergency surgery are at particularly high risk of mortality, so these patients may benefit from their procedures being postponed," Bhangu added.

The study also noted that patients undergoing surgery are a vulnerable group at risk of SARS-CoV-2 exposure in hospital.

It noted that the patients may also be particularly susceptible to subsequent pulmonary complications, due to inflammatory and immunosuppressive responses to surgery and mechanical ventilation.

The scientists found that overall in the 30 days following surgery 51 per cent of patients developed a pneumonia, acute respiratory distress syndrome, or required unexpected ventilation.

Nearly 82 per cent of the patients who died had experienced pulmonary complications, the researchers said.

"Worldwide an estimated 28.4 million elective operations were cancelled due to disruption caused by COVID-19," said co-author Dmitri Nepogodiev from the University of Birmingham.

"Our data suggests that it was the right decision to postpone operations at a time when patients were at risk of being infected with SARS-CoV-2 in hospital," Nepogodiev said.

According to the researchers, there's now an urgent need for investment by governments and health providers in to measures which ensure that as surgery restarts patient safety is prioritised.

They said this includes the provision of adequate personal protective equipment (PPE), establishment of pathways for rapid preoperative SARS-CoV-2 testing, and consideration of the role of dedicated 'cold' surgical centres.

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News Network
January 17,2020

New Delhi, Jan 17: E-commerce major Amazon on Friday said it plans to create one million new jobs in India over the next five years through investments in technology, infrastructure and its logistics network.

These jobs are in addition to the seven lakh jobs Amazon's investments have enabled over the last six years in the country.

"Amazon plans to create one million new jobs in India by 2025," the company said in a statement, adding that the jobs - created both directly and indirectly - will be across industries, including information technology, skill development, content creation, retail, logistics, and manufacturing.

Amazon.com Inc chief Jeff Bezos had on Wednesday announced USD 1 billion (over Rs 7,000 crore) investment in India to help bring small and medium businesses online and committed to exporting USD 10 billion worth of India-made goods by 2025.

"We are investing to create a million new jobs here in India over the next five years," Bezos said.

"We’ve seen huge contributions from our employees, extraordinary creativity from the small businesses we've partnered with, and great enthusiasm from the customers who shop with us—and we’re excited about what lies ahead," Bezos added.

India has prioritised job creation and skilling initiatives – including the training of more than 400 million people by 2022 – in rural and urban areas.

"Amazon’s job creation commitment and investment in traders and micro, small and medium enterprises (MSMEs) complement this social inclusion and social mobility efforts by creating more opportunities for people in India to find employment, build skills, and expand entrepreneurship opportunities," the statement said.

The new investments will help to hire talent to fill roles across Amazon in India, including software development engineering, cloud computing, content creation, and customer support.

Since 2014, Amazon has grown its employee base more than four times, and last year inaugurated its new campus building in Hyderabad – Amazon’s first fully-owned campus outside the United States and the largest building globally in terms of employees (15,000) and space (9.5 acres).

The investments will also help in expanding growth opportunities for the more than 5,50,000 traders and micro, small, and medium-sized businesses – including local shops – through programs like Saheli, Karigar, and “I Have Space”.

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