IIT-G develops device that separates oil from water

Agencies
August 19, 2019

New Delhi, Aug 19: Researchers at the Indian Institute of Technology (IIT) Guwahati have developed a device that can continuously separate oil from water by strategic use of fish-scale and lotus-leaf inspired membranes.

The team developed the system of materials by combining the lotus leaf-inspired super-water repellence and fish scale-mimicked underwater super-oil repellence.

The membranes that are super-water repellent in air, and super oil-repellent in water, have been shown to separate complex mixtures of oil and water at practically relevant settings, according to the journal ACS Sustainable Chemistry & Engineering.

Oil-water separation is also important in environmental applications like oil spill management.

The team then developed a prototype of oil-water separation device using these membranes so that the separated oil and water were simultaneously collected in different containers.

"Oil-water separation is of current relevance because many industries, such as mining, textiles, food and petrochemicals, produce massive volumes of oily wastewater, which must be treated before discharge," said Uttam Manna, Assistant Professor, Department of Chemistry, IIT Guwahati.

The lotus leaf for example, is water repellent so that it does not get soggy in its living space, researchers said.

Fish, on the other hand, has a body surface that repels oil in order to survive in polluted waters, they said.

Scientists have studied the surface structures of lotus leaves and fish scales to understand what gives them their superhydrophobicity (super-water repellence) and superoleophobicity (super-oil repellence), so that these structures can be replicated artificially for oil-water separation applications.

Lotus leaf-inspired superhydrophobic materials and fish scale-inspired superoleophobic materials were developed following a single and unique deposition process and tested for gravity-driven removal of oil from water.

While these bio-inspired membranes are individually used to separate oil and water in the recent past, there is accumulation of water or oil on the membrane over time, which blocks further separation.

"There is yet another problem with conventional demonstration, where the superhydrophobic and superoleophobic materials are mostly used for two phase oil/water mixtures," Manna said.

"However, those approaches are inappropriate for separation of three-phase mixtures of heavy oil, light oil and water," he said.

These materials are required to operate under harsh conditions; they are subjected to severe stretching and bending during operation, which make them physically unstable, researchers said.

In order to overcome the problems, Manna and his team developed a system of 'super liquid repellent' materials, by combining the lotus leaf superhydrophobicity and fish scale superoleophobicity.

Layer-by-layer deposition technique was used to obtain alternating layers of 'chemically reactive polymeric nano-complex' and 'amino graphene oxide nanosheets' on a stretchable and fibrous substrate.

The durable and stretchable membranes that the team developed were super-water-repellent in air and super-oil-repellent in water.

"These separation systems allow continuous, parallel and selective separation of various oil/water mixtures, irrespective of surface tension, density, and viscosity of the oil phase and chemical complexity in the water phase," Manna said.

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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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Agencies
January 3,2020

Giving each and every app access to personal information stored on Android smartphones such as your contacts, call history, SMS and photos may put you in trouble as bad actors can easily use these access to spy on you, send spam messages and make calls anywhere at your expense or even sign you up for a premium "service", researchers from cybersecurity firm Kaspersky have warned.

But one can restrict access to such information as Android lets you configure app permissions. 

Giving an app any of these permissions generally means that from now on it can obtain information of this type and upload it to the Cloud without asking your explicit consent for whatever it intends to do with your data.

Therefore, security researchers recommend one should think twice before granting permissions to apps, especially if they are not needed for the app to work. 

For example, most games have no need to access your contacts or camera, messengers do not really need to know your location, and some trendy filter for the camera can probably survive without your call history, Kaspersky said. 

While decision to give permission is yours, the fewer access you hand out, the more intact your data will be.

Here's what you should know to protect your data.

SMS: An app with permission to send and receive SMS, MMS, and WAP (Wireless Application Protocol) push messages, as well as view messages in the smartphone memory will be able to read all of your SMS correspondence, including messages with one-time codes for online banking and confirming transactions.

Using this permission, the app can also send spam messages in your name (and at your expense) to all your friends. Or sign you up for a premium "service." You can see and conrol which apps have these rights by going to the settings of your phone.

Calendar: With permission to view, delete, modify, and add events in the calendar, prying eyes can find out what you have done and what you are doing today and in the future. Spyware loves this permission.

Camera: Permission to access the camera is necessary for the app to take photos and record video. But apps with this permission can take a photo or record a video at any moment and without warning. Attackers armed with embarrassing images and other dirt on you can make life a misery, according to Kaspersky.

Contacts: With permission to read, change, and add contacts in your address book, and access the list of accounts registered in the smartphone, an app can send your entire address book to its server. Even legitimate services have been found to abuse this permission, never mind scammers and spammers, for whom it is a windfall.

This permission also grants access to the list of app accounts on the device, including Google, Facebook, and many other services.

Phone: Giving access to your phone means permission to view and modify call history, obtain your phone number, cellular network data, and the status of outgoing calls, add voicemail, access IP telephony services, view numbers being called with the ability to end the call or redirect it to another number and call any number.

This permission basically lets the app do anything it likes with voice communication. It can find out who you called and when or prevent you from making calls (to a particular number or in general) by constantly terminating calls. 

It can eavesdrop on your conversations or, of course, make calls anywhere at your expense, including to pay-through-the-nose numbers, Kaspersky warned.

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Agencies
July 13,2020

New Delhi, Jul 13: The Income Tax Department has facilitated a new functionality for banks and post offices to ascertain TDS applicability rates on cash withdrawal of above Rs 20 lakh in case of a non-filer of the income-tax return and that of above Rs 1 crore in case of a filer of the income-tax return.

In a statement, the Central Board of Direct Taxes (CBDT) said that now banks and post offices have to only enter the PAN of the person who is withdrawing cash for ascertaining the applicable rate of TDS.

So far, more than 53,000 verification requests have been executed successfully on this facility, a statement by the CBDT said.

"CBDT today said that this functionality available as 'Verification of applicability u/s 194N' on www.incometaxindiaefiling.gov.in since 1st July 2020, is also made available to the Banks through web-services so that the entire process can be automated and be linked to the Bank's internal core banking solution," it said.

On entering PAN by the bank or the post office, a message will be instantly displayed on the departmental utility: "TDS is deductible at the rate of 2 per cent if cash withdrawal exceeds Rs 1 crore", in case the person withdrawing cash is a filer of the income-tax return.

In case the person withdrawing cash is a non-filer of income tax return, the message shown would be: "TDS is deductible at the rate of 2 per cent if cash withdrawal exceeds Rs 20 lakh and at the rate of 5 per cent if it exceeds Rs 1 crore."

The CBDT said that the data on cash withdrawal indicated that huge amount of cash is withdrawn by the persons who have never filed income-tax returns.

To ensure filing of return by these persons and to keep track on cash withdrawals by the non-filers, and to curb black money, the Finance Act, 2020 with effect from July 1, 2020 further amended IT Act to lower threshold of cash withdrawal to Rs 20 lakh for the applicability of this TDS for the non-filers and also mandated TDS at the higher rate of 5 per cent on cash withdrawal exceeding Rs 1 crore by the non-filers.

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