The last few years have witnessed tremendous changes in the syllabi of environmentally
related courses at Advanced Level and in tertiary education. Moreover, there have been
major alterations in the way degree and diploma courses are organised in colleges and
universities. Syllabus changes reflect the increasing interest in environmental issues,
their significance in a political context and their increasing relevance in everyday life.
Poverty is a severe problem in Africa, Asia, South America and even in pockets of the
developed world. Addressing poverty alleviation via the expanded use of biological
nitrogen fixation in agriculture was the theme of the 15th International Congress on
This report is a product of the Panel to Review the Critical Ecosystem Studies Initiative—a panel organized
by the National Research Council (NRC) in response to congressional concerns that the restoration of the greater
Everglades ecosystem be supported by the best possible science. The Critical Ecosystem Studies Initiative
(CESI) has been the primary investment by the U.S. Department of the Interior to provide scientific information
to advise restoration decision-making and to guide its own land management responsibilities for South Florida
Tham khảo sách 'biological nitrogen fixation: towards poverty alleviation through sustainable agriculture', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả
Spinal fusion remains at the center of many reconstructive procedures of the spine. However,
several new concepts have recently emerged, which led many spine surgeons to rethink
traditional approaches to common clinical problems.
The need for reconstruction of the torn anterior cruciate ligament (ACL) in
the active patient is not controversial. There are, however, many other
aspects of ACL reconstruction that are widely debated. Examples of the
topics under discussion include type of graft, single or double bundle, type
of fixation, and graft healing.
This issue of Clinics in Sports Medicine reviews some of the most common
topics of discussion for surgeons performing ACL reconstruction. Specifically,
this issue reviews the variety of grafts most commonly used.
Biological nitrogen fixation is a vital process in the global nitrogen
cycle, transforming dinitrogen in the atmosphere into ammonia.
Being a very energy-demanding and oxygen-sensitive process, both
expression and activity of the nitrogenase enzyme are tightly regu-lated. Rhodospirillum rubrumis a free-living, photosynthetic, purple
non-sulfur nitrogen-fixing bacterium, which has been extensively
used as a model organism for metabolic and regulatory studies
regarding nitrogen fixation.
Photosynthesis is the primary source of energy for all life forms (except chemolithotrophic prokaryotes). Much of the energy of photosynthesis is used to drive the synthesis of organic molecules from atmospheric CO2. How is solar energy captured and transformed into metabolically useful chemical energy? How is the chemical energy produced by photosynthesis used to create organic molecules from carbon dioxide?
The success of anterior cruciate ligament (ACL) reconstruction: Initial tensile properties of the graft tissue; the initial fixation of the graft; the healing at the graft fixation sites,
The biologic remodeling of the graft; type of postoperative rehabilitation program used.