crushing and griding

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weird animal's...... It’s a Bear-Eat-Bear World Out There, Literally

So there you are, trundling through the forest. A powerful black bear, lord of the food web, you’re eating up berries, maybe catching some fish, when, all of a sudden, you’re being eaten by a massive grizzly.

That scene, or something like it, played out in Banff National Park in Alberta, Canada, earlier in August, when hikers came across a grizzly eating a black bear.

The U.S. Fisheries and Wildlife Service says that grizzly bears are opportunistic omnivores:

It will eat plants, as well as insects and other animals. Scavengers by nature, grizzlies spend most of their waking hours searching for food. Forbs, roots, tubers, grasses, berries and other vegetation, and insects comprise most of the bear’s diet. But grizzlies are very adaptable, finding and subsisting on a variety of foods if necessary.

In Yellowstone this means moths, snapped up by the tens of thousands. In Banff, apparently, it means other bears.

Steve Michel, who works at Banff, says “he suspects the kill was opportunistic,”

“Grizzly bears are opportunistic hunters,” he said. “They will take advantage of any food source that presents itself.”

Bears eating other bears isn’t entirely new—polar bears will eat each other, especially each others’ young. But for grizzlies it’s much more novel. Though how novel is up for debate. Michel told  that he “knows of four other instances when a grizzly has hunted, killed and eaten a black bear in Banff.”

“It may not be as rare as we think it is,” he said. “But it is rare that we actually are able to document it. We tend not to know about it all.”

Research may lead to inexpensive, flexible solar cells

Work by a team of chemical engineers at Penn State and Rice University may lead to a new class of inexpensive organic solar cells.

"Imagine if you could make solar cells as easily as you can print posters or newspapers—you could make sheets of this," said Enrique Gomez, assistant professor of chemical engineering. "It represents a fundamental shift in the way in which we make solar cells."

Most solar cells today are inorganic and made of crystalline silicon. The problem with these, Gomez explained, is that inorganic solar cells tend to be expensive, rigid and relatively inefficient when it comes to converting sunlight into electricity.

But organic solar cells offer an intriguing alternative that's flexible and potentially less expensive.

Not many organic solar cells currently exist. He said, "There are a bunch of prototypes floating around. You see them in places like in solar-powered laptop bags and on the top of some bus depots."

The problem is that the bulk of organic solar cells employ fullerene acceptors—a carbon-based molecule that's extremely difficult to scale up for mass production.

Gomez's approach skips the fullerene acceptor altogether and seeks to combine molecules in a solution.

The idea of utilizing molecular self-assembly for solar cells isn't new, but Gomez said, "It's not been well executed."

He continued, "It's like trying to mix oil and water." The issue is that weak intermolecular interactions and disorder at junctions of different organic materials limited the performance and stability of previous organic solar cells.

But by controlling the nanostructure and morphology, the team essentially redesigned the molecules to link together in a better way.

The engineers were able to control the donor-acceptor heterojunctions through microphase-separated conjugated block copolymers.

"We have not only demonstrated control of the microstructure, but also control of the interface responsible for the initial steps in charge photogeneration in a way never achieved before," Gomez said.

The result, which was detailed in a recent issue of the American Chemical Society's Nano Letters journal, is an organic solar cell made of block copolymers that's three percent efficient.

The team included Penn State chemical engineering graduate student Changhe Guo; undergraduate student Matt Witman; Rafael Verduzco, the Louis Owen Assistant Professor of Chemical and Biomolecular Engineering at Rice University; Joseph Strzalka, research scientist at Argonne National Laboratory; and research scientists Cheng Wang and Alexander Hexemer of Lawrence Berkeley National Laboratory.

Though the team's prototype is not as efficient as some solar cells that are commercially available, Gomez explained the work shows flexible organic solar cells are indeed possible.

"Our cells right now don't capture a lot of light. We need to look back and redesign the molecule. We think we can do better than 3 percent," he said.

HEC announces ranking of universities 2013

The Higher Education Commission (HEC) on Friday announced ranking of public sector universities in the country.

According to the ranking based on the 2011-12 data provided by the institutions, the University of Agriculture Faisalabad, Pakistan Institute of Engineering and Applied Science, Islamabad, Lahore University of Management Sciences (Lums), the Aga Khan University (AKU), Karachi, National University of Sciences and Technology, Islamabad, Quaid-i-Azam University Islamabad and the University of Faisalabad were placed on the top of the national list.

For the first time, some universities from the remote areas also managed to get into the top five positions in different categories. These are: Sindh Agriculture University, Tandojam, the Institute of Business Administration (IBA), Sukkur, the Mehran University of Engineering and Technology, Jamshoro, Gomal University D.I. Khan, University of Science and Technology, Bannu, and Liaquat University of Medical and Health Sciences, Jamshoro.

In the agriculture/veterinary category, the top five universities are: University of Agriculture Faisalabad, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, University of Veterinary and Animal Sciences, Lahore, the University of Agriculture Peshawar and Sindh Agriculture University, Tandojam.

In the engineering and technology category, the Pakistan Institute of Engineering and Applied Science, Islamabad, University of Engineering and Technology Lahore, Ghulam Ishaq Khan Institute of Engineering and Technology, Swabi, Mehran University of Engineering and Technology, Jamshoro, and Institute of Space Technology, Islamabad, were on top of the list.

In the business education, the Lahore University of Management Sciences (Lums), the Institute of Business Administration, Karachi, the Institute of Business Administration, Sukkur, and Shaheed Zulifikar Ali Bhutto Institute of Science and Technology, Karachi, were on the top.

In the medical category, the Aga Khan University (AKU), was ranked at the top followed by the University of Health Sciences, Lahore, Dow University of Health Sciences, Karachi, Liaquat University of Medical and Health Sciences, Jamshoro, Khyber Medical University, Peshawar, and King Edward Medical University, Lahore.

The general category has been divided into three sub-categories - large, medium and small. In the general universities (large), the National University of Sciences and Technology, Islamabad, University of the Punjab, Lahore, University of Karachi, the Comsats Institute of Information Technology Islamabad and Government College University Faisalabad were placed on the top.

The top general universities (medium) included Quaid-i-Azam University Islamabad, Government College University, Lahore, National University of Computer and Emerging Sciences, Islamabad, Fatima Jinnah Women University Rawalpindi and Gomal University, D.I Khan.

General universities (small): The top institutions are: University of Faisalabad, Beaconhouse National University, Lahore, Pakistan Institute of Development Economics (PIDE), Islamabad, University of Science and Technology, Bannu, Isra University, Hyderabad, and Foundation University, Islamabad.

Speaking to a press conference, HEC Chairperson Dr Javaid R. Laghari said the primary purpose of the ranking exercise was to drive the higher education institutions (HEIs) towards improved quality.

The ranking criteria for the universities revolve around three main parameters: implementation status of quality assurance criteria, teaching quality and research. The HEIs established after December 2008 and the distance education institutions like AIOU and Virtual University were excluded from the ranking list.

In reply to questions of the mediapersons, Mr Laghari said in general category universities having over 7,000 students were considered large, less than 7,000 students medium and universities having less that 3,000 students small.

He said there were different divisions of the HEC that verified the universities and awarded them marks for having facilities, PhD faculty members and research work. He said from the next year OIC will also adopt the criteria of HEC for ranking the universities of its member countries.