Search

Plant susceptibility to pathogens is usually considered from the perspective of the loss of resistance. However, susceptibility cannot be equated with plant passivity since active host cooperation may be required for the pathogen to propagate and cause disease. This cooperation consists of the induction of reactions called susceptible responses that transform a plant from an autonomous biological unit into a component of a pathosystem. Induced susceptibility is scarcely discussed in the literature (at least compared to induced resistance) although this phenomenon has a fundamental impact on plant-pathogen interactions and disease progression. This review aims to summarize current knowledge on plant susceptible responses and their regulation. We highlight two main categories of susceptible responses according to their consequences and indicate the relevance of susceptible response-related studies to agricultural practice. We hope that this review will generate interest in this underestimated aspect of plant-pathogen interactions.

Synopsis The connection between structure and function is one of the fundamental tenets of biology: a biological unit’s structure determines its function, and, conversely, its function depends upon its structure. Historically, important advances have been made either when understanding of structure leads to questions about function or when understanding of function raises questions about the structures involved. Consequently, considering the connections between structure and function from a broader perspective might lead to the development of novel hypotheses that move our understanding of the fundamental connections between structure and function forward. Better integration of structure and function is a key component in the broader goal of reintegrating biology within and across scales. Here, we provide examples of how integrating studies of structure and function as well as comparing structure–function relationships across biological scales can lead to scientific advances. We also emphasize the potential of integrating studies of structure and function across scales for bio-inspired design and for improving biology education.

Cell is the basic structural and biological unit of organisms. Conventional methods for detecting population cells often conceal individual differences between cells. Therefore, efficient single-cell analysis strategies are urgently needed for in-depth studies of cell life activities, revealing the mechanism of disease developments, and promoting individualized diagnosis and treatment. Micro-nano electrochemical sensors play an important role in real-time dynamic monitoring of single cells, due to its small size, high temporal and spatial resolution. At present, micro-nano electrochemical sensors have made important progress in the electrode preparation, high-performance sensing interface construction, theoretical analysis and breakthroughs have been made in single-cell real-time monitoring and related mechanism research. However, complex internal environment, low concentration of active molecules, and dynamic changes in time and space put forward higher requirements on the sensitivity and selectivity of micro-nano electrochemical sensors for single cell detection. Our research group has been engaged in the construction of micro-nano electrochemical sensing interface and its application in real-time dynamic monitoring of single cells and subcellular structures. This feature article mainly introduces our research progress in this field in the past 10 years, and discusses challenges and opportunities in the future.

In this study we followed the way in which evolves the behaviour of some honeybee families (Apis mellifera carpathica, Linnaeus), maintained in vertical beehives (modified Dadant type), in conditions of stationary bee keeping, having in view the natural queen cell’s build rhythm after the second acacia tree harvest (Robinia pseudoacacia L.) in Jucu area of Cluj County. There were taken into observation 20 biological units with queen bees of different ages. It was monitored the development rhythm of natural queen cells, which are in attendance by the working bees, and to put into evidence the swarming instinct strength, so in bee keeping practice to be known and to be avoided the natural swarming. The determination of occupied surfaces with covered brood and larval was effected with the Netz framework. The aim of our study was to understand how the swarming in honeybees occurs. By detailed observation, we want to describe and to explain the behaviour of honeybees before the swarming process. The obtained results are quantified in absolute values and expressed graphically in relative values, but in the next three apicultural years (2020, 2021 and 2022), the experiment will be repeated for a variance analysis, which will provide a statistical assurance. We hope that these data will give contribution for the apicultural practice, keeping attention on queen bees’ importance during active season and on careful supervision on development rhythm of the honeybee units during the natural swarming.

The cell is the basic functional and biological unit of life, and a complex system that contains a huge number of molecular components. How can we quantify the macroscopic state of a cell from the microscopic information of these molecular components? This is a fundamental question to increase the understanding of the human body. The recent maturation of single-cell RNA sequencing (scRNA-seq) technologies has allowed researchers to gain information on the transcriptomes of individual cells. Although considerable progress has been made in terms of cell-type clustering over the past few years, there is no strong consensus about how to define a cell state from scRNA-seq data. Here, we present single-cell entropy (scEntropy) as an order parameter for cellular transcriptome profiles from scRNA-seq data. scEntropy is a straightforward parameter with which to define the intrinsic transcriptional state of a cell that can provide a quantity to measure the developmental process and to distinguish different cell types. The proposed scEntropy followed by Gaussian mixture model (scEGMM) provides a coherent method of cell-type classification that is simple, includes no parameters or clustering and is comparable to existing machine learning-based methods in benchmarking studies. The results of cell-type classification based on scEGMM are robust and easy to biologically interpret.

Cells are a fundamental structural, functional and biological unit for all living organisms. Up till now, considerable efforts have been made to study the responses of single cells and subcellular components to an external load, and understand the biophysics underlying cell rheology, mechanotransduction and cell functions using experimental and in-silico approaches. In the last decade, computational simulation has become increasingly attractive due to its critical role in interpreting experimental data, analysing complex cellular/subcellular structures, facilitating diagnostic designs and therapeutic techniques, and developing biomimetic materials. Despite the significant progress, developing comprehensive and accurate models of living cells remains a grand challenge in the 21st century. To understand current state of the art, this review summarises and classifies the vast array of computational biomechanical models for cells. The article covers the cellular components at multi-spatial levels, i.e., protein polymers, subcellular components, whole cells and the systems with scale beyond a cell. In addition to the comprehensive review of the topic, this article also provides new insights into the future prospects of developing integrated, active and high-fidelity cell models that are multiscale, multi-physics and multi-disciplinary in nature. This review will be beneficial for the researchers in modelling the biomechanics of subcellular components, cells and multiple cell systems and understanding the cell functions and biological processes from the perspective of cell mechanics. This article is protected by copyright. All rights reserved.

In their paper “How Causal are Microbiomes? A Comparison with the Helicobacter pylori Explanation of Ulcers,” Lynch, Parke, and O’Malley successfully argue that certain causal attributions made to the microbiome have not satisfied Koch’s postulates nor the interventionist framework. However, their argument involves an implicit assumption that cases such as H. pylori are sufficiently similar to cases involving the microbiome, such that causal attributions to both should be evaluated according to the same causal framework. Our commentary targets this assumption. First, we introduce the historical circumstances that led to the formulation of Koch’s postulates in order to differentiate the case of the microbiome from that of infectious bacteria. Then, we introduce the concept of the holobiont, the idea that hosts and their symbionts should be conceptualized as a metaphysical and biological unit. Finally, using the holobiont concept, we argue that Koch’s postulates and the interventionist framework are ill-equipped to handle the microbiome. We conclude by suggesting that a revision of what counts as microbiological causality within the holobiont is justified.

Patterns of the development of acoustic signaling were traced in a honey bee family. The acoustic connections between queen bees competing for survival in the period of sociotomy were shown to originate at the initial phases of bee colony development. The response of bees to the queen’s singing (a pause in locomotion) developed, since this promoted a reduction in the time spent by the family on completing sociotomy. The development of sociality was associated with the acquisition of an unconditioned reflex-acoustic interaction between the signaling bees and the workers mobilized by them. The acoustic communication signals and sounds that accompany the life of bees have ensured the transformation of a bee family into an evolving biological unit in the species phylogeny.

The bioengineering of individual microbial organisms or microbial communities has great potential in agriculture, bioremediation and industry. Understanding community level drivers can improve community level functions to enhance desired outcomes in complex environments, whereas individual microbes can be reduced to a programmable biological unit for specific output goals. While understanding the bioengineering potential of both approaches leads to a wide range of potential uses, public acceptance of such technology may be the greatest hindrance to its application. Public perceptions and expectations of “naturalness,” as well as notions of disgust and dread, may delay the development of such technologies to their full benefit. We discuss these bioengineering approaches and draw on the psychological literature to suggest strategies that scientists can use to allay public concerns over the implementation of this technology.

In the first longitudinal study of bat microbiomes, we find that unlike the pattern described in humans and other mammals, the prominent dynamics in Egyptian fruit bats’ fur microbiomes are those of change over time at the level of the colony as a whole. Thus, on average, a pair of fur microbiome samples from different individuals in the same colony collected on the same date are more similar to one another than a pair of samples from the same individual collected at different time points. This pattern suggests that the whole colony may be the appropriate biological unit for understanding some of the roles of the host microbiome in social bats’ ecology and evolution. This pattern of synchronized colony changes over time is also reflected in the profile of volatile compounds in the bats’ fur, but differs from the more individualized pattern found in the bats’ gut microbiome.

Background: Skin prick test results are mostly reported as mean wheal diameter obtained with one concentration of allergen. Differences in technique between personnel causes variation in wheal size. The research question was whether the influence of differences in skin prick test technique among assistants and centers can be reduced by relating the allergen wheal response to that of histamine. Methods: Two methods for estimating skin reactivity, the method of Nordic Guidelines using histamine as a reference and the method of Brighton et al. [Clin Allergy 1979;9:591-596] not using histamine as a reference, were applied to data from two biological standardization trials, using the same batch of freeze-dried timothy pollen preparation. Results: The concentration defining the Nordic biological unit, defined as a concentration of allergen eliciting a wheal of the same size as that of histamine dihydrochloride 10 mg/ml, did not differ between the centers. When not using histamine as a reference, applying the method of Brighton et al., there was a 15-fold difference in the estimate of the biological activity between the trials that was eliminated by adjusting the allergen response to that of the histamine reference. Conclusions: To reduce the influence of differences in test technique among assistants and centers responses to allergen-induced skin prick tests should be compared to that of histamine.

Summary Life is based on the cell as the elementary replicative and self-sustaining biological unit. Each single cell constitutes an independent and highly dynamic system with a remarkable individuality in a multitude of physiological traits and responses to environmental fluctuations. However, with traditional population-based cultivation set-ups, it is not possible to decouple inherent stochastic processes and extracellular contributions to phenotypic individuality for two central reasons: the lack of environmental control and the occlusion of single-cell dynamics by the population average. With microfluidic single-cell analysis as a new cell assay format, these issues can now be addressed, enabling cultivation and time-resolved analysis of single cells in precisely manipulable extracellular environments beyond the bulk. In this article, we explore the interplay of cellular physiology and environment at a single-cell level. We review biological basics that govern the functional state of the cell and put them in context with physical fundamentals that shape the extracellular environment. Furthermore, the significance of single-cell growth rates as pivotal descriptors for global cellular physiology is discussed and highlighted by selected studies. These examples illustrate the unique opportunities of microfluidic single-cell cultivation in combination with growth rate analysis, addressing questions of fundamental bio(techno)logical interest.

The most evident aspect of biodiversity is the variety of complex forms and behaviors among organisms, both living and extinct. Comparative molecular and physiological studies show that the evolution of complex phenotypic traits involves multiple levels of biological organization (i.e. genes, chromosomes, organelles, cells, individual organisms, species, etc.). Regardless of the specific molecular mechanisms and details, the evolution of different complex biological organizations share a commonality: cooperation and conflict among the parts of the biological unit under study. The potential for conflict among parts is abundant. How then do complex systems persist, given the necessity of cooperative behavior for their maintenance, when the potential for conflict occurs across all levels of biological organization? In this Research Topic and eBook we present ideas and work on the question, how coexistence of biological components at different levels of organization persists in the face of antagonistic, conflicting or even exploitative behavior of the parts? The goal of this topic is in presenting examples of cooperation and conflict at different levels of biological organization to discuss the consequences that this “tension” have had in the diversification and emergence of novel phenotypic traits. Exemplary cases are studies investigating: the evolution of genomes, formation of colonial aggregates of cells, biofilms, the origin and maintenance of multicellular organisms, and the stable coexistence of multispecies consortia producing a cooperative product. Altogether, we hope that the contributions to this Research Topic build towards mechanistic knowledge of the biological phenomenon of coexistence in the face of conflict. We believe that knowledge on the mechanisms of the origin and evolutionary maintenance of cooperation has implications beyond evolutionary biology such as novel approaches in controlling microbial infections in medicine and the modes by studies in synthetic biology are conducted when designing economically important microbial consortia.The most evident aspect of biodiversity is the variety of complex forms and behaviors among organisms, both living and extinct. Comparative molecular and physiological studies show that the evolution of complex phenotypic traits involves multiple levels of biological organization (i.e. genes, chromosomes, organelles, cells, individual organisms, species, etc.). Regardless of the specific molecular mechanisms and details, the evolution of different complex biological organizations share a commonality: cooperation and conflict among the parts of the biological unit under study. The potential for conflict among parts is abundant. How then do complex systems persist, given the necessity of cooperative behavior for their maintenance, when the potential for conflict occurs across all levels of biological organization? In this Research Topic and eBook we present ideas and work on the question, how coexistence of biological components at different levels of organization persists in the face of antagonistic, conflicting or even exploitative behavior of the parts? The goal of this topic is in presenting examples of cooperation and conflict at different levels of biological organization to discuss the consequences that this “tension” have had in the diversification and emergence of novel phenotypic traits. Exemplary cases are studies investigating: the evolution of genomes, formation of colonial aggregates of cells, biofilms, the origin and maintenance of multicellular organisms, and the stable coexistence of multispecies consortia producing a cooperative product. Altogether, we hope that the contributions to this Research Topic build towards mechanistic knowledge of the biological phenomenon of coexistence in the face of conflict. We believe that knowledge on the mechanisms of the origin and evolutionary maintenance of cooperation has implications beyond evolutionary biology such as novel approaches in controlling microbial infections in medicine and the modes by studies in synthetic biology are conducted when designing economically important microbial consortia.

Petrochemical manufacturing wastewaters often contain a high concentration of biodegradable compounds that possess either toxicity or activity inhibition to the biological unit. In this paper, a comparison between aluminum and iron plate electrodes on COD and color removal from Petrochemical wastewaters by electro-Fenton process was studied. The experiments were conducted to evaluate the effects of reaction time, current density, pH, H 2 O 2 /Fe 2+ molar ratio, and H 2 O 2 of petrochemical wastewater (PW) (ml/l) on the performance of the process. Response surface methodology (RSM) was employed to assess individual and interactive effects of the five main independent parameters on the COD and color removal. The results show that COD and color removal efficiencies of iron electrode (67.3% and 71.58%, respectively) were more than those of aluminum electrode (53.94% and 67.35%, respectively).

Regularities of the appearance of family in the bee superfamily have been analyzed. It is shown that conversion in highly organized eusocial bee species into the biological unit is coupled to perfection of instincts of care of offspring of the female-founderer, an increase of its lifespan, with strengthening of various forms of domination. The concept is substantiated that development of offspring of dominating females under similar conditions ruling out the intranest competition as well as strengthening of interconnection and interdependence between members of the family have led to the appearance of family selection.

Honeybees communicate through a multichannel system implemented in complex instincts, realization of which is stimulated by bees’ needs that vary depending on physiological state and ecological situation. The mechanisms of generation and perception of communication signals are multifunctional. In species phylogeny, acoustical and other forms of communication promoted consolidation and transformation of the bee family into an evolutionary biological unit. The broad ecological valency of the honeybee is in great measure associated with development of an efficient, reliable, and economical communication system.

Stingless bees are eusocial hymenopteran and the colony is the biological unit of the species. Different castes (queen, drones and workers) are present in the colony that may be considered a superorganism since isolated individuals do not survive. The colony shows a spatial organization, given by its architecture, characteristic of each species, and a temporal organization, established by sequences of processes and behaviours repeated at regular intervals, equally species-specific. In the same colony several rhythms can be detected both in individuals and in the colony altogether. The properties of these rhythms may be different but phase relations are established among them, originating a general rhythmic expression, consequence of the internal temporal order of the colony. As is the case with metazoan organisms, the establishment of the internal temporal order assures the super-organism survival

From the beginning of the twenty-first century, there has been a shift towards studying biological processes using a holistic rather than a reductionist scientific paradigm thus establishing the approach now named “systems biology” or “systomics”. This method of biological investigation represents a synergy where life sciences, systems engineering, and information technology examine the interactions between biological pathways, rather than solely focusing on individual pathways in an isolated manner. To date, systems biology has often studied population averages rather than individual characteristics of cells which might display a significant spread. However, as a single cell is the smallest operational biological unit that encompasses all metabolites necessary for maintaining a viable living entity, the application of systems biology approaches to the study of distinct cells is fast becoming a goal of many research groups. In this chapter we will describe some of the technologies that enable the isolation of individual cells in a form that accommodates systomics studies, the biological methods that are then deployed on such isolated cells to generate system-level information, and finally describe some of the bioinformatics that is specifically directed towards single-cell studies.

Thermovision and thermometric methods were used to study temperature variations in honeybee nests and in aggregations of honeybees isolated from their families. Endogenous and exogenous circadian rhythms of thermoregulatory activity and their physiological mechanisms were revealed. The magnitude of changes in this activity in response to ambient temperature decreased from the beginning to the end of wintering, which was due to the existence of a genetically determined self-regulation program in honeybees. The improvement of this program in the course of the species evolution contributed to transformation of a honeybee family into a reproducible biological unit.

The combination of solar irradiation and Fenton reagent have been used to enhance the biodegradability (BOD(5)/COD) of chlorophenol wastewater, including 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), and 2,4-dichlorophenol (2,4-DCP). Results showed that the solar photo-Fenton process improved significantly the biodegradability of chlorophenol wastewater. Basically, increasing initial H(2)O(2) dosage was much more beneficial for increasing biodegradability of wastewater than increasing initial Fe(2 + ) dosage. Among the conditions studied, the optimum condition of increasing biodegradability of chlorophenol wastewater was found with a [H(2)O(2)](0)/[Fe(2 + )](0)/[chlorophenol](0) ratio of 10.0/0.2/1.0, 10.0/0.3/1.0, and 10.0/0.2/1.0 for 2-CP, 4-CP, and 2,4-DCP, respectively. As a result, the value of BOD(5)/COD was increased from 0 for untreated solution up to 0.231, 0.248, and 0.193 for 2-CP, 4-CP, and 2,4-DCP, respectively with a 15-min treatment. Under the operation of optimum conditions, the oxidative state of chlorophenol wastewater could be easily controlled into a higher biodegradability stage. The COD and TOC degradation efficiency could be in excess of 90% on the whole as the preoxidized chlorophenol solution was treated by a following batch-type biological unit. In the meanwhile, the microtoxicity of wastewater reduced more than 95%.

This article discusses the use of microneedles in automated diabetes therapy systems. Advanced bioengineered systems have the potential to close the loop between diagnostic and therapeutic elements of diabetes treatment, thus constituting a “smart” system. Prevalent insulin therapies, and most glucose sensing techniques, involve the transfer of physical entities through the skin. Micromachined needles (microneedles) can achieve this in a noninvasive or minimally invasive manner while contributing various other technological merits. The dynamics of autonomous diabetes therapy systems include highly complex interdependencies between the various physical and biological entities involved, thus warranting multidisciplinary research initiatives. The iterative development of a noninvasive, bioengineered interface such as microneedles necessitates a better understanding of the human skin, its molecular architecture as a polymer film, and its role as a functional biological unit. This review addresses application-specific requirements of a microneedle-based interface system specifically for autonomous diabetes therapy. Key design issues and related parametric interdependencies specific to this application are discussed.

For breastfeeding to start and continue, the newborn must be able to suck, swallow, and breathe; the mother must be able and willing to let her infant breastfeed; and surroundings must support the biological unit: the mother-baby dyad. This article reviews how birth practices, including epidural anesthesia, cesarean surgery, forceps, and vacuum extraction, can affect the newborn's ability to feed, the mother's motivation and lactation capacity, and the mother-baby relationship.

PiQSi facilitates the manual investigation of the quaternary structure of protein complexes in the Protein Data Bank (PDB). Users can browse and obtain an overview of the quaternary structure information of a given protein together with its evolutionary relatives, which helps in the determination of the biological quaternary state. I have used this framework to annotate over 10,000 structures from the PDB Biological Unit and corrected the quaternary state of approximately 15% of them. A benchmark shows that the annotations are of high quality and stresses the need for manual curation, in particular for ambiguous cases such as proteins in equilibrium between two quaternary states. The approximately 10,000 annotations already in the database can be used to improve the accuracy of analyses on protein structure or to benchmark methods that predict protein quaternary structure. In addition, PiQSi incorporates a community-based curation system, which I hope will allow us to reach an accurate and complete description of the biological quaternary state of proteins in PDB. PiQSi is accessible at http://www.PiQSi.org/.

The concept of the cell has been based on metaphor since its inception, and the history of cell theory has continued to rely on metaphor and analogy. In the nineteenth century, cells were most popularly conceived either as building stones or elementary autonomous organisms from which larger organisms are composed. With advances in physiology and the rise of modern biochemistry in the early twentieth century, the chemical factory or laboratory became the dominant metaphor for this biological unit. Today in the twenty-first century, the metaphorical imagery has become a reality, with cells acting as chemical factories for the synthesis of commercially valuable bio-products. The history of the cell shows how metaphors act as conceptual tools, with particular strengths for facilitating different sorts of questions and experimental techniques.

Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this paper, we calculated the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculated the mutual information, energy cost, and energy efficiency of an array of these bistable units. We found that the optimal number of units could maximize this array's energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection., Comment: 5 pages, 3 figures, submitted to Chinese Physics Letter

Infrared (IR) rays, which comprise approximately 40% of the solar radiation which reaches the earth's surface, have received relatively scant attention. As no standard method has yet been agreed upon for the biological evaluation of IR irradiation, the objective of this study is to suggest a new unit for IR irradiation.The skin temperature of 38 Korean volunteers was measured after IR irradiation with varying irradiance.Skin temperature after IR irradiation at an irradiance of 2.02 W/cm2 remained unchanged after 652+/-22 s (mean+/-standard error), which corresponds, in this case, to a total radiation dose of IR 1317.3+/-44.84 J/cm2. This quantity was designated as the minimal heating dose (MHD). We also demonstrated that MHD increased with increasing IR irradiance at lower IR irradiance (1.17 and 2.02 W/cm2), whereas it became constant at higher irradiance (2.87 and 3.22 W/cm2). No statistically significant correlations were detected between MHD and volunteers' ages, erythema index, or melanin index.We propose 'MHD' as a biological unit for the measurement of IR irradiation.

The movement of populations shapes the patterns and distribution of infectious diseases globally. The consequences of travel are seen in the traveller and in places and populations visited and may persist long after travel. The traveller can be seen as an interactive biological unit who picks up, processes, carries and drops off microbial genetic material. A traveller can introduce potential pathogens in the absence of signs or symptoms of illness. Travellers can serve as a sentinel population; study of them can provide insights into the presence and level of risk of transmission of infections in other geographical regions. Travellers can also be seen as couriers who inadvertently ferry pathogens and microbial genetic material to regions where researchers can carry out detailed analyses that can help to map the location and movement of strains, genotypes and resistance patterns. The laboratory plays a key role in the identification and characterization of pathogens, which can inform management of individual patients and the public health response. The connectedness and mobility in the world today facilitate the emergence of infectious diseases in humans and also in animals and plants. Many traditional barriers have been breached by travel, roads and technology. Population size and density favour spread of many infections. The rapid generation time of microbes and their capacity to adapt to changes in the physico-chemical and immunological environment will pose continuing challenges.

Despite the most unflattering epithets and fear, pain was and still remains the normal response of any living organism on strong physical, chemical or mechanical stimuli. It has the most important protection function in nature – at just the right time pain immediately signals about appearance of exogenic or endogenic destructive effects on a certain organ [1-6], and it is simply necessary for the organism’s survival as a biological unit. Unfortunately, it presents not only by disagreeable sensation. Being rather complex psychophysiological phenomenon pain (especially strong and continued) is often accompanied by very powerful emotional stresses [7-9], which can rapidly exhaust the body’s adaptation resources and cause the serious disorders of its vital functions. Obviously it is for this reason that International Association for the Study of Pain considers pain as a global factor causing problems in modern society not only of medical, but also of socio-economic character [10-13].

Over the past few decades there has been a lot of work in the field of synthetic biology, in order to understand the underlying concepts and cast them as a problem in chemistry, mathematics or engineering. Moulding it into control engineering, the majority of the problems arise, either due to synthesizability of the designed controller (as a Biological unit) or tackling robustness in a multi-network, to achieve the desired specifications. In this paper, we stress on how a biologically synthesizable robust controller could be designed using a novel approach of Linear Matrix Inequality (LMI) based loop shaping.

One constant challenge in biotechnological applications such as biosensors or biofuel cells is the immobilization of the bio-entity on respective surfaces. Beside widely used covalent binding, entrapment in polymers, or cross linking, protein or DNA grafting via supramolecular host–guest systems or metal–organic coordination, called affinity interactions, became a powerful alternative. One clear advantage of this principle is the facilitated formation of the biocomposite since the biological unit can be immobilized via self-assembly just by incubation of a surface, modified with a corresponding counterpart, in the biomolecule, bearing the other counterpart, containing the solution. The most important affinity systems to immobilize bioreceptor units onto transducer surfaces are summarized. Original examples of this immobilization strategy are not only used for biosensing applications but also for other biotechnological fields like biofuel cells.

The Protein Data Bank is a key source of knowledge about protein structure and function. As of June 2013, it contained over 91 000 experimentally determined structural models of proteins and nucleic acids. This chapter aims to outline the different types of problems associated with these models that prospective users should be aware of. The problems include errors of varying magnitude, both global and local. Not all structural models represent the entire protein, or the protein’s ‘biological unit’. Further problems arise with very large structures or complexes which advances in technology now allow to be solved.

Anaerobic treatment of tannery wastewater in high rate close type reactors leaves sulphide in the range 31–795 mg/l, COD 395–1886 mg/l, BOD 65–450 mg/l and TOC 65–605 mg/l. Thus post anaerobic treatment of wastewater was required to meet discharging standard. High sulphide concentration present in treated wastewater may render aerobic biological treatment unsuitable. Hence, it became essential to include sulphide removal unit operation preceeding aerobic biological unit. Among the techniques available oxidation of sulphide by air using activated carbon as catalyst gained importance for its removal of COD, BOD and TOC inaddition to elimination of sulphide in wastewater. The effect of [S2‐/O2] ratio and hydraulic loading rate on removal of sulphide and organics in counter current reactor containing activated carbon were discussed. The percentage removal of COD, BOD, TOC and Sulphide from anaerobically treated wastewater were respectively 81, 85, 82 and 100. The sulphate content of catalytically oxi...

Chlorophytum heynei Baker (1876: 322) was described based on a collection of Rottler from India in 1816. This species is characterized by elliptic-obovate with pseudopetiolate (petiole 5–8 cm channeled), scape shorter than the leaves, absence of sterile bracts; greenish flowers, anthers shorter than the filaments and papillose filaments (Robi et al. 2015). Most of the recent literature (Sasidharan & Sivarajan 1996, Sivarajan & Mathew 1997, Sasidharan 2013) misidentified this species with C. palghatense K.M.P.Kumar & Adsul (Prabhu et al. 2014: 282), but Robi et al. (2015: 78) resolved the taxonomy of these names. Unaware of this work, plants of Chlorophytum (Ker Gawler 1808: 1071) were described as C. clivorum Mathew & George (2015: 379), based on collections in the mountain forests of Achankovil (part of Achankovil Shear Zone), in Kollam district of Kerala. The critical analysis of the type specimens and protologues associated with both names shows that both the names C. heynei and C. clivorum apply to the same biological unit. Hence, C. heynei holds nomenclatural priority (McNeill et al. 2012, Art. 11.4).

The BIOMOL grant was for 'Local System Support for PDB Biological Unit Search and Display' to augment Rasmol's [Bernstein 2000] [Sayle, Milner-White 1995] existing macromolecular display functions with new capabilities by taking advantage of recent increases in local computing power in order to move functionality that is now scattered among various local and remote systems into one local package. Work included new algorithms for molecular surface display, an extended format for Protein Data Bank Entries, work on issues relating to the integration of multiple diffraction images formats.