eChapters

Plants play an important role in maintaining ecological balance by actively participating in the cycling of nutrients and gases like carbon dioxide, oxygen and air pollutants. Sensitivity and responses of plants to air pollutants is variable. Some plants are sensitive and act as bio indicators of air pollution (Kozhouharov et. al. 1985, Guderian, 1998). Others which are tolerant may act as sink to air pollutants. However this aspect needs more investigation for their use as indicators of air pollutants and in abatement of air pollution.

Air

Estimation of Total Suspended Particulate Matter (TSPM) and Respirable Suspended Particulate Matter (RSPM)

Requirements
Instrument

High Volume Sampler (HVS) APM 415-411 (Envirotech Instrument India), Respirable Dust Sampler (RDS) APM 451 (Envirotech Instrument India) with midget impinger containing absorbing solution were used.

Pollution is continuously increasing in India. To control ambient air pollution CPCB has prescribed National Ambient Air Quality Standards

True/False

Q.1.    Statistics in singular is used to denote a subject (branch) of science.
Q.2.    Statistics in plural is used to denote “data or methods”
Q.3.    Statistics is defined as a science of collection, compilation, analysis and interpretation of numerical data.
Q.4.    Statistics can be used for two major purposes: descriptive and infe-rential.

True/False
 
Q.1.    The set of observations or measurements collected on specific characteristics from each item (individual) constitutes data.
Q.2.    Each characteristic that is measured or observed, varies from item to item and is called “Variable”.
Q.3.    “Blood type”, “stage of disease” and “weight” observed on a group of cancer patients, are three distinct variables.
Q.4.    A variable that can be expressed in numbers such as age, height, blood pressure, is said to be “Quantitative variable”.

True/False

Q.1.    A set containing all possible outcome of a trial in a study is known as “Sample space”.
Q.2.    If we are interested in observing the blood type of a child born in a hospital then sample space may be a set S is of the form S = {A, B, AB, O}.
Q.3.    If outcomes are continuous in nature, the sample space is specified as an interval that contains all possible outcome values.
Q.4.    When the occurrence of one event excludes the occurrence of other events, the events are said to be “Mutually exclusive events”.
Q.5.    In case of testing the type of blood of a newly born baby in a hospital, the blood types A, B, AB, O or gender (male, female) are exclusive events.

True/False

Q.1.    The set of all possible outcomes of a variable along with the frequency (the number of occurrence) of each outcome or a group of outcome is called “Frequency Distribution”.
Q.2.    The frequency of an occurrence of each outcome of a trail divided by total frequency is known as “Relative frequency” of the outcome.
Q.3.    The distribution of total probability “1” into probabilities of occurrence of each outcome of a trial, is known as probability distribution of the outcome.

True/False

Q.1.    Collectivity (totality) of all sampling units is known as the “Population” and population size is denoted by “N”.
Q.2.    A list of all sampling units with their identification is known as “Sampling frame”. For example a list of all newly-born children in maternity home during a period of three months with specification of their sex, weight, name of their parents, their permanent address, etc. is known as sampling frame.
Q.3.    A function of all sampling units in the population is known as population parameter or population constant.

True/False

Q.1.    The process of knowing all the relevant information from the known sample to the unknown “Population parameter” is known as “Statistical inference.”
Q.2.    The method of estimating the unknown parameter of the population on the basis of known sample values is known “Estimation method.”
Q.3.    The “Point estimation and Interval estimation” are the two methods of estimating the unknown parameters of the population.

True/False

Q.1.    A hypothesis that sets the fundamental objective of scientific study is called the “Research hypothesis”.
Q.2.     A statistical assumption or statement about the unknown parameters of a population is known as Statistical hypothesis.

True/False

Q.1.    According to Prof. RA Fisher “ANOVA” is the separation of variance assignable to one group of causes from the variance assignable to other group of causes.
Q.2.    The basic purpose of ANOVA technique is to test the equality (homogeneity) of several population means from the same 
experiment.

True/False

Q.1.    Qualitative or categorical data are frequently collected in medical investigation.
Q.2.    Qualitative variables may be, e.g. sex, blood type, treatment, groups, classification of exposure or disease and patients survived or not.
Q.3.    Qualitative variables include the grouped quantitative variables such as age groups of mothers, pre term babies, birth weight groups, 
hypertensive or normotensive etc.

True/False

Q.1.    The most fundamental assumption for “Parametric inference” is that the random sample drawn is from “Normal” population.
Q.2.    The most fundamental assumption of “Non-parametric” test is that the random sample drawn is from “Continuous distribution”
Q.3.    The standard parametric methods are applicable for “Estimating the parameter” as well as for “Testing the hypothesis” about the parameters.
Q.4.    Non-parametric methods, are applicable only for testing the hypothesis about  distribution but not applicable for estimation purpose of parameter.

True/False

Q.1.    Two independent random variables (X,Y) are always uncorrelated but reverse may not be true

True/False

Q.1.    The purpose of most medical research is to identify the causes of disease and search out the ways to prevent or cure them.
Q.2.    Now a day, epidemiology has become a basic science for public health
Q.3.    The studies of diagnostics therapeutic and prognostic procedures have successfully incorporated into growing stream of “Clinical Epidemiology”.

True/False

Q.1.    In clinical practice and in public health, the objective is to find better ways to ‘prevent,  diagnose and treat disease’.
Q.2.    Among all research designs, experimental study designs are the most reliable and  ideal designs to evaluate the ‘effectiveness or value’ of interventions (like drugs,  medication etc.) for human disease and disabilities.

True /False

Q.1.    A diagnostic test enables the doctors to reach at a decision whether the patient is suffering from a particular disease or not.
Q.2.    The recent developments in the field by biotechnology have led to the development of many new medical tests.
Q.3.    The general principles in designing and conduct diagnostic test studies are not known well.

True/False

Q.1.    In many epidemiological studies with substantial follow up time, it is very often an interest to study the time taken for a particular event to occur.
Q.2.    The time taken for death or graft failure since transplant, time taken for relapse after treatment, time to death after treatment etc. are examples for survival time.

True/False

Q.1.    The accuracy of the measurement refers to how close the measured value is to the true value.
Q.2.    The precision refers to how close a set or group of measurements are together.
Q.3.    If the processes of measurement are repeated under identical condition, then precision explains that up to what extent these repeated values are reliable.

True/False

Q.1.    Demographic data and vital statistics are important tools for researchers, epidemiologists, health planners and health professionals.
Q.2.    The distribution of people across different geographic regions is known as population density.

True/False

Q.1.    In many clinical research studies, the regression analysis is used to develop models for prediction of an outcome from one or more explanatory variables.
Q.2.    Now a days, the linear, logistic and Cox (proportional hazards) regression models are used frequently in medical research.

True/False

Q.1.    The precision of an estimator increases as the sample size increases.
Q.2.    Statistical power is the probability that a statistical test will indicate a significant difference is true i.e. it is the probability of taking correct decision.

Abstract

Dietary phytochemicals and herbal medicines are under intensive investigation for their potential as chemopreventive agents against various diseases due to the wide variety of microbial and plant functionally relevant secondary metabolites. The chemical diversity of phytochemicals, as well as phytochemicals and complex metabolic interactions between the biological systems may exceed the capacity of the platforms of traditional analysis, and therefore pose major challenges in the study of chemopreventive phytochemical compounds.

Abstract

Biotechnology offers an opportunity to exploit the cell, tissue, organ or entire organism by growing them in vitro and to genetically manipulate them to obtain desired compounds. It plays a pivotal role in search for alternatives to production of desirable biomedical compounds. There are several approaches have been used to increase the yield of metabolites from cell cultures such as manipulation of nutrient medium, application of exogenous growth stimulators, chemical treatment, precursor feeding, elicitation, transformed cultures, metabolic engineering, micropropagation, bioreactor cultures and etc.

Abstract

Quercus species of family Fagaceae are very important from both economic and ecological perspectives. These exhibit irregular fruiting, and produce seeds recalcitrant to storage, thereby difficult to propagate through conventional procedures. Again because of their very difficult to root nature, extremely limited success has been observed in vegetative propagation. Application of new technological approaches like in vitro propagation may be of interest for accelerating tree improvement programs to these hardwood species. This review provides a summary of the advancement in the application of in vitro propagation to oak species of Kumaun West Himalaya India.

Abstract

Bamboo is nature’s unique gift to mankind. It has tremendous scope for use in eco-friendly agro-forestry programmes, to bring marginal lands into use. The requirement for bamboo is increasing for various traditional and industrial requirements. In India almost 99% of annual bamboo production comes from the natural forests and only about 1% is derived from plantations.

Abstract

Bacilli, a group of endospore forming bacteria present in soil, contribute directly or indirectly to crop productivity. Bacilli have many physiological unique traits like multilayered cell wall, stress resistant endospore formation, secretion of peptide antibiotics, peptide signal molecules, extracellular enzymes, which make them ubiquitous and assist to their survival under adverse environmental conditions for long time.

Abstract

Biosurfactants (BS) are amphiphilic compounds produced by microorganisms mainly bacteria and are known to contain hydrophobic and hydrophilic moieties that play a major role in reducing surface tension (ST) and interfacial tensions between individual molecules. Chemically, BS is a complex molecules consisting of lipopeptides, glycolipids, polysaccharide protein complex, fatty acids and phospholipids. They are known for their biodegradability, low toxicity, and renewable nature.

Abstract

Thermophiles mainly harbor in highly temperate environments such as hydrothermal vents, hot springs, fumaroles etc. The main importance of thermophiles is due to their thermostable proteins, enzymes and their adaptive mechanisms at higher temperature which are very useful for industrial applications. The main rationale behind this research was to isolate industrially important thermophilic bacteria from the Hot Springs of Sikkim which can be used as tools for genetic engineering and vector based research activities.

Abstract

Since the beginning of the civilization, medicinal plants have been used to prevent and treat various ailments. At present, most of the pharmaceutical/ nutraceutical industries highly depend on wild medicinal plants for the supply of raw materials for extraction of bioactive compounds. As medicinal plants receive increased scientific and commercial attention, there is increasing pressure on the wild medicinal plant populations.

Abstract

Modern world is experiencing energy insecurity because of extreme population pressure and depleting energy resources. Fossil fuels though have highly applauded for contributing to today’s development, are non renewable energy and debated for not sustainable. This has posed serious challenges to the scientific fraternity for finding the suitable alternatives. A cheap, eco-friendly, sustainable or renewable type of energy is visualized for development with added advantage of mitigating green house gases.

Abstract

Nanotechnology is an emerging field that offers various potential applications in the areas of agriculture, health and medicine. Recent advances in the design and synthesis of nano-materials aids for developing sophisticated nano-devices for clinical research and practice. Applications of nano materials in medicine includes disease diagnosis, early prognosis, detection of pathogens, tumor detection, tissue engineering, target  specific drug delivery,  development of  biomaterials  for oral health  and understanding of cellular mechanisms in live cells using molecular imaging.

Abstract

Cancer is a potent disease causing nearly 6 million deaths per year worldwide. There are a number of cancers such as skin, brain, lung, breast, stomach, colon and blood cancer caused due to number of factors like unbalancing of hormones, smoking etc. Cancer could be treated by chemotherapies or through irradiation therapies.

Abstract

As we have entered in the post genomic era where we have successfully completed the full genome sequencing of many important crop species and now the future challenge is to ascertain the functions of all genes present in plant genome.

Abstract

Meta analysis quantitatively summarizes the findings of a large collection of individual experiments. It is a powerful statistical tool since it integrates a vast literature and thus includes large sample size. It leads to a stronger conclusion than traditional literary review as studies are analyzed applying statistical methods. Meta- analysis is increasingly being applied in different fields of biological sciences. It has been emerged as an independent subfield of modern health science researches as in this field very few studies achieve statistical power in isolation. Meta- analysis has also become an integral part of plant science research, e.g., agricultural research, ethnobotanical research, tea and health science research etc. Meta-analysis has few limitations although rigorously conducted meta- analyses are considered more valuable than any single study contributing to the analysis.

Abstract
 
Food products can have moisture content as high as 90% which needs to be lowered to acceptable limits to prevent microbial growth and deteriorative reactions. Drying is one of the most common and cost effective techniques for removal of excess moisture from the food by application of heat. In addition to its role of extending the product shelf life and providing stability, drying also helps to produce variety of products from agricultural, horticultural and industrial products. But to obtain the desired quality product, adequate drying is essential which depends on type of dryer and drying technique employed which further requires proper understanding of drying process. Despite being important unit operation in food processing industry, appropriate scientific knowledge of the drying process is still limited. So, the fundamental principles and associated terminologies with drying has been discussed in detail in this chapter to have thorough understanding of the drying process. In addition, different models and calculation procedures for drying of different types of commodities has also been reviewed.

Abstract

Classification of the hundreds of possible dryers is essential to the logical selection of appropriate dryer for a given application. Diverse criteria for classification as well as selection of dryers are presented and discussed briefly. The advantages and limitations of different dryer types must be taken into consideration. Initial capital cost is often the key deciding criterion in industrial dryer selection. This is not a good strategy as the user must pay for the operating costs over a long period of life of the dryer. In general several different dryer types are suitable for a given product. Careful selection is essential for cost-effective operation of the dryer.

Abstract

Osmotic dehydration is gaining popularity due to several energy and product quality related advantages it offers. It has huge potential as a complementary process step prior to operations such as air-drying, microwave drying, freezing, frying etc, if not an alternative one, in the food process chain. It can be easily integrated with other processing steps in order to improve the overall efficiency of a given food process. Application of additional driving force either prior to or during osmotic dehydration can enhance the mass transfer rates in the osmotic dehydration. Role of mathematical modelling both in osmotic dehydration and rehydration have been discussed. Current limitations for the adaptation of osmotic dehydration in the food processing industry and possible solutions are also discussed in detail.

Abstract

Spray drying is one of the most preferred methods of converting food and pharmaceutical solutions into powder form. Very high product throughput, hygienic and highly automated process and relatively benign thermal and dehydration stress on products associated with this process has made it ubiquitous in powder manufacture. Compared to freeze drying, spray drying is significantly less expensive both in terms of operation and capital costs. In this chapter, key features of spray drying such as underlying operational principle, types of spray nozzles used, the flow pattern of droplets/particles and drying medium within the drying chamber, the particle formation process of individual droplet are discussed in considerable detail. The modelling aspect of a single droplet subjected to spray drying environment has also been included. Finally, the most commonly considered characteristics of spray dried powders including morphology, crystalline/amorphous nature and solubility are highlighted and discussed.  The content presented in this chapter will be very useful for practising engineers, technologists, researchers as well as postgraduate and undergraduate students.

Abstract

Hot air circulation is the most common industrial method of drying foods which has its own inherited disadvantages. Microwave drying can be an alternative method for removing moisture from foods and there has been a surge of interest in the application of microwave to process the foods, in past few years. The reason being that there is worldwide energy crisis and the growing acceptance and familiarity with domestic microwave ovens. It is well known that conventional means of heat processing irreversibly alter the flavor, colour, and texture of many foods. From the point of flavor alone, it is desirable to improve our present methods of processing foods. Some improvements have been made in this direction with a number of food products by use of high-temperature short- time processing.

Abstract

In recent years microwave processing have attained increasing recognition in food industries particularly in drying and dehydration. During microwave processing, electromagnetic energy is supplied directly to the food material for volumetric heating. This provides rapid temperature rise throughout the material with reduced thermal gradients. This unique heating mechanism reduces processing time and saves energy. In-spite of advantages of microwave heating it leads to overheating in food material and formation of cold and hot spots if applied improperly during drying. To overcome these challenges different microwave assisted hybrid drying technologies have been developed by many researchers. These techniques are microwave assisted hot air drying, microwave assisted osmotic dehydration, microwave assisted vacuum drying, microwave- infrared assisted hot air drying, microwave assisted rotary drying. This chapter comprises the fundamentals of microwave and provides comprehensive update of microwave assisted hybrid drying processes for food and agricultural materials.

Abstract

Drying is a very important unit operation in food processing. Being an energy intensive unit operation, drying process demands improvement to make it energy efficient. Beside this operating conditions used in drying affect product quality substantially; however, traditional dryers do not allow enough flexibility to meet quality requirements for several products. This has resulted in development of number of new drying techniques, to cope with both energy efficiency and product quality.

Abstract

The objective of this chapter is to provide an overview of heat pump dryer (HPD) and recent developments in its applications for drying of agricultural and food products. The basics of heat pump dryer, classification, operating principle, configuration and control system have been presented for better understanding. Many researchers have concluded that HPDs use energy more efficiently than electrical dryers. The heat pump dryer is best suited for drying high value commodities such as fruits, vegetables, spices, condiments, herbs, medicinal and aromatic plants at near ambient temperature for producing better quality dehydrated product.

Abstract
 
Grains are usually harvested above 20% (wb) moisture level and they are prone to microbial attack at high moisture level. In order to avoid both qualitative and quantitative losses that arise from microbial growth, grains are usually dried to safe moisture level. The safe storage moisture content may vary from 8-16% (wb), depending upon the grain and climate type. Therefore, drying is a necessary step in preventing these losses. Drying also reduces the bulk weight of the materials, thus easing transportation and storage. Drying can occur in thin layer or in deep bed. Different drying theories are proposed to characterize these drying processes. Theoretical as well empirical drying equations have been developed.

Abstract

Recently, the reduction of post harvest food losses around the globe is a critical issue for ensuring future food security. Drying techniques is important option to prevent losses and preserve food for long time. The solar thermal energy required to remove moisture from the food during the drying process can be optimized by designing suitable solar dryers. Moreover, the application of solar energy in drying of agricultural products has tremendous potential, since it can easily provide the low temperature heating required for drying and helps in reduction of CO2 emissions. Hence, the present chapter deals with descriptions of different types of solar dryers used to dry various types of agricultural food products and design of solar dryers. Also, the heat and mass transfer parameters with respect to various process variables to estimate the performance of the food dryer system were analyzed. The advantages of solar dryers in terms of net CO2 emissions mitigation potential and the quality attributes of dried food products are also discussed. It is suggested that properly designed solar dryers having low operational cost compared to electrically heated dryers may prove to be an energy saving device for drying of agricultural products. However, the techno-economical and environmental aspects of various efficient solar dryers are needed to be further studied for applications in various irregular shaped food products.

Abstract

The primary commercial energy sources such as coal, oil and natural gas poses an enormous challenge to our development goals including environmental degradation, as India is not well endowed with these exhaustible natural resources. Further, these conventional sources are also not available in right quantity and producing environmental pollution manifold in land, air and water. There are number of unit operations in food processing and value addition consuming bulk of conventional energy sources where renewable energy sources can easily be integrated for energy conservation and environment protection. There is significant potential for application of Renewable Energy Sources in different unit operation of food processing including drying of food products for energy conservation and for reducing hydrocarbon emissions.

Abstract
 
Drying is one of the most popular methods used for preserving products and extending their shelf lives by reducing moisture content to a low level to prevent microbial spoilage and moisture-mediated deteriorative reactions. As an efficient technology with high heat and mass transfer rates, impingement drying has been commonly used in various industrial drying such as tissue paper, textiles, photographic films, coated paper, nonwovens, carpets, lumber etc. In the past two decades, air impingement technology has got more and more attention in the field of food and agricultural products processing.

Abstract

There are several empirical models to describe deep bed drying dividing the domain into many thin layers. Empirical equations are seen as a resource that only serves to describe the thin layer drying kinetics of an agricultural product. Normally an empirical model is used to determine drying rate. The validity of following thin-layer drying models are accounted by coefficient of correlation (R2), standard error of estimated (SEE), root mean square error (RMSE). The properties of dried foods vary substantially depending upon the type of product, moisture content, drying type and ultimately drying conditions. To take care all above variables, a promising approach is to use Artificial Neural Network (ANN). In process control, the main objectives are food safety, high quality and yield at minimal costs. To obtain high quality products, on-line control techniques are required. Most food processes are highly nonlinear, with time varying dynamics, which complicates food automation. However, the recent developments in artificial intelligence based advanced control tools such as ANN to food processing have opened up novel possibilities for processing industries.

Abstract

Food dehydration is an oldest method to increase the shelf life of food by reducing the water activity. A dried food product provides advantages of increased shelf life and reduced cost due to decreased weight as well as transportation. However, there is a decrease in product quality due to inadequate control on drying process parameters such as drying temperature and moisture removal together with change in thermo-physical properties of food. Computational modeling and simulations can provide a unique insight on the drying parameters that influences the product quality, and optimize the process conditions which are difficult by experimental analysis. Moreover, the computational techniques are advantageous over experimental optimization methods by minimizing the time and cost. This chapter reviews different computational modeling techniques such as, finite element modeling, finite volume and finite difference methods for modeling of food dehydration process. Also, this chapter describes the application of modeling techniques for determining the influence of shrinkage and porosity during dehydration.

Abstract

It is well known that drying is an important unit operation in food processing industries, essentially used to extend the shelf life but also in making innovative processed products such as snacks with desired functionalities. Although drying of food products is carried out traditionally using several methods, the quality and energy aspects have been major focus of food drying research in the last decade or two. This is achieved by modifying and/or optimizing the existing drying systems, improving pre and post processing of the product, combination of more than one dryer type or developing altogether a new drying technique. There several dryer types which can give extremely good product quality, however, cost-effectiveness can be a major issue. It is necessary to balance both good product quality and minimum energy usage in order to sustain highly competitive market. This lecture will provide an overview of conventional drying methods used for foods, followed by some advances in these conventional methods and a discussion on some new drying techniques developed in recent years that are either commercialized or have potential of industrial use.