Advanced Botany

  Plastic products have brought great convenience to our lives by way of its scalable manufacturing process, light weight, robust mechanical properties, versatility, low cost and resistance to corrosion. These products have been widely used in various fields such as packaging, food industry, electronics, construction and many other industries; among which about 16 billion disposable coffee cups are consumed every year and half billion plastic straws are discarded every day worldwide. However, it takes as long as 450 years or even longer for some plastics to degrade especially single-use plastics bags, lunchboxes and disposable cups, accounting for 40% of the total plastic production and rendering severe “white pollution”.  Meanwhile, every year about 8 million tons of plastic waste is dumped into oceans, which has caused significant harm to marine life. Current treatment to plastic includes land filling, incineration and recycling among which landfill treatment is the prim...

  It is difficult to give an exact definition for the life, as the nature of life is not clear. According to Encarta@ Wodd English Dictionary, definition of living is: "Spiritual existence transcending physical death; the period from birth to death; the quality that makes living animals and plants different from dead organisms and inorganic matter. Its functions include the ability to take in food, adapt to the environment, grow, and reproduce". The biological world is viewed as a hierarchy of levels. These levels include chemicals, organelles, cells, organs, organisms, and ecologies. There are three conceptions for life: as a loose cluster of properties, a specific set of properties, and metabolization. Several hundred years ago, people thought that there was a vitalism inside life bodies that keep the body to be a life. The scientific results absolutely denied the existence of vitalism. The demise of vitalism told us that no super physical substance or force or spirit...

  The first person to create a system of rules to classify living organisms was a Greek scientist and philosopher named Aristotle. He pointed out that classification requires two steps. First, organisms have to be carefully described and second to identify and describe their functions. For example in an electronics store, one way to classify items is by function. But before store owners can put an item in an aisle, they need to identify and then describe the function of the item. Earlier, living organisms were just given names that described where they were found. The same organism might have twenty different names, which led to confusion. Hence, living organisms are classified mainly to avoid confusion, to make study of organisms easy and learn how various organisms are related to each other. Scientists classified living organisms into different kingdoms, phylum, class, etc and are based on different criteria. Earth is a home for millions of living species including micr...

  The world has become an urban society, with over half the world’s populations living in urbanized areas. Historically, urbanization was related to positive economic development and provided many opportunities such as education and good infrastructure, but overexposure to stress caused mental health problems. Urbanization negatively affects mental health by influencing increased stressors and factors such as overcrowded and polluted environments, high noise levels, higher crime rates, reduced social support, and lack of calming scenery. Therefore, it is crucial to find ways of promoting mental health recovery in daily life. Forest therapy has been proposed as one of the solutions for stress recovery and health promotion and has recently received widespread attention as a novel approach to achieving physiological and psychological relaxation. Connecting with forests has been increasingly recognized as an effective method of dealing with mental problems. Inspired by the ...

  Atomic spectrometry is the most obvious choice of technique to be used for metal determination in vegetation samples. In WD-XRF spectrometry the characteristic radiation emitted from the sample is separated into wavelengths using a diffraction device. Usually in WD-XRF spectrometers, the analysis of different elements is carried out in a sequential way by scanning synchronously the orientation of the mono chromator device and the detector (2θ). In multi-channel spectrometers, the use of several diffraction devices set-ups allows one to measure several elements simultaneously. DEFINITION Wavelength dispersive x-ray fluorescence spectroscopy (WD XRF) is a non-contact, non-destructive technique used to measure elemental composition, elemental concentration per unit area, and film thickness. Due to its acute element sensitivity, it is particularly useful for identifying trace elements. WORKING OF WDXRF   In a WDXRF measurement, the sample is irradiated with high ...

  Photosynthetic organisms fuel their metabolism with light energy and have developed for this purpose an efficient apparatus for harvesting sunlight. Chlorophylls serve as light-harvesting antennae by capturing the sunlight and are assisted in their light-harvesting role by carotenoids. The light-harvesting complex (LHC) is an array of protein and chlorophyll molecules embedded in the thylakoid membrane of plants and cyanobacteria, which transfer light energy to one chlorophyll a molecule at the reaction center of a photosystem (the functional unit in photosynthesis). It consists of a number of chromophores which are complex subunit proteins. LHC is used by plants and photosynthetic bacteria to collect more of the incoming light than would be captured by the photosynthetic reaction center alone. The light which is captured by the chromophores is capable of exciting molecules from their ground state to a higher energy state, known as the excited...