Mechanism and nature

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Understanding the nature and mechanism of foot pain

Understanding the nature and mechanism of foot pain

Approximately one-quarter of the population are affected by foot pain at any given time. It is often disabling and can impair mood, behaviour, self-care ability and overall quality of life. Currently, the nature and mechanism underlying many types of foot pain is not clearly understood. Here we comprehensively review the literature on foot pain, with specific reference to its definition, prevalence, aetiology and predictors, classification, measurement and impact. We also discuss the complexities of foot pain as a sensory, emotional and psychosocial experience in the context of clinical practice, therapeutic trials and the placebo effect. A deeper understanding of foot pain is needed to identify causal pathways, classify diagnoses, quantify severity, evaluate long term implications and better target clinical intervention.

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Medieval Robots: Mechanism, Magic, Nature, and Art

Medieval Robots: Mechanism, Magic, Nature, and Art

Already in classical antiquity, the display of stunning artificial wonders was prioritized over their possible application to the necessities of life (in part, of course, because Aristotle had forcibly downgraded ‘useful knowledge’ as a lower form of praxis and philosophical occupation). Archytas of Tarentum, as early as the fourth century BC, apparently constructed a flying mechanical dove, and there are reports that two second- century writers, Ctesibius and Philo, wrote on water-organs, water clocks and automata. Finally, Hero of Alexandria, the most prolific ancient writer on mechanical devices, who flourished in the first century AD, covered a wide range of topics, including some explicitly aimed at exciting wonder – like, for instance, an automatic theatre retrofitted with thunder and burning fire. Hero, who appears to have worked in an environment where Aristotelianism was well-known, presented useful knowledge as competitive with philosophical writings and rhetorical displays; Hero’s earliest translators, and early modern pursuers of the Alexandrian school more generally, inherited this ambiguous conflation of technical illustration and philosophical pretension. Indeed, automata of Hero’s type and pseudo-Aristotelian mechanics, during the Middle Ages, were given a higher set of preoccupations in alignment with the philosophical trope of Natura artifex (Nature as artisan, or the description of Nature’s labor in artisanal terms), as opposed to the practical consequences of hydraulic engineering in farming, mining, transport and warfare.

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The nature, origin and mechanism of development off flavour in frozen cod (Gadus morhus)

The nature, origin and mechanism of development off flavour in frozen cod (Gadus morhus)

of t he mibetrete# If a radical lose occurs by the reactione shown in the general scheme, a number of products will b e produced whose amount and ty pe will depend not only on idiioh of the mechanisms 1,2 or 3 predominate but also on the relative iiq>ortanoe of the chain termination mechanism to that of the propagating mechanisms. When Im plied to the autoxidation of sp ecific lipid moi eties it has been shown that Aee radical abstraction of hydrogen from the li pid takes pl ace at the weakest oarbon-hydrogen bond^idiioh is situated at the methylene gtoap oC to the double bond position. fbr mono- enes, such as oleic acid, there are thus two positions of attack (Chart IT). After abstraction it has been observed that four monohydrop eroxides are

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A High-Throughput Method for Cloning and Sequencing Human Immunodeficiency Virus Type 1 Integration Sites

A High-Throughput Method for Cloning and Sequencing Human Immunodeficiency Virus Type 1 Integration Sites

Integration of retroviral DNA is nonspecific and can occur at many sites throughout chromosomes. However, the process is not uniformly distributed, and both hot and cold spots for integration exist. The mechanism that determines target site specificity is not well understood. Because of the nonspecific and widespread nature of integration, studies analyzing the mechanism and factors that control target site selection require the collec- tion and analysis of a large library of human immunodeficiency virus type 1 (HIV-1) proviral clones. Such analyses are time-consuming and labor-intensive using conventional means. We have developed an efficient and high-throughput method of sequencing and mapping a large number of independent integration sites in the absence of any selection or bias. The new assay involves the use of a modified HIV-1 (NL-Mme) containing a type IIS restriction site, MmeI, at the right end of viral DNA. Digestion of genomic DNA from NL-Mme- infected cells generated viral DNA-containing fragments of a discrete size. Subsequent ligation-mediated PCR yielded short integration site fragments termed Int-tags, which were concatemerized for determining multiple integration sites in a single sequencing reaction. Analysis of chromosomal features and sequence preference associated with integration events confirmed the validity of the new high-throughput assay. The assay will aid the effort in understanding the mechanisms of target site selection during HIV-1 DNA integration, and the described methodology can be adapted easily to integration site studies involving other retroviruses and transposons.

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Electronic Transport Processes In Two-dimensional Solid Solutions

Electronic Transport Processes In Two-dimensional Solid Solutions

electrical and optical properties, are potential candidates for use in various transducers, light modulators, and information storage units. However, until now not studied dc- and ac-electronic processes in layer GaSe 1  x S x crystals. The investigation of electric properties of materials in dc-and ac-electric fields gives information about the nature of charge transport and localization states in forbidden gap. For the establishment of mechanism of charge transport it is necessary to know the temperature and frequency dependences of dc-and ac-conductivity. The objectives of this work were to study the dc-and ac- electrical properties of GaSe 1  x S x single crystals, to gain insight into the mechanism of charge transport in the crystals, and to evaluate the parameters of localized states in their band gap.

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Sense and response in the cell

Sense and response in the cell

A precise determination of identity and strength of the stimulus is a pre-requisite for the signal transduction in the cell (Lahav, 2004; Batchelor, Loewer and Lahav, 2009; Batchelor et al., 2011; Purvis et al., 2012). This is crucial as downstream responses have to be graded according to the stress in order to induce flexible cellular outcomes. The classical understanding of cellular signal transmission comes from the receptor-ligand mechanism. Although the specificity of ligands for receptors facilitates activation of their respective signaling pathways by the precise identification of stimulus, its static nature to trigger the response at a fixed time does not necessarily manifest into the gradation of response (Lahav, 2004; Purvis and Lahav, 2013). Signal transduction through the static mechanisms could be assumed to follow ‘all or none’ principle where receptor-ligand complex association or dissociation at a given time either generates or terminates the downstream transmission. For instance, G-protein coupled receptors (GPCRs) activate cyclic adenosine monophosphates (cAMPs) upon ligand binding to control membrane channel functions.

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Native Functions of the Androgen Receptor are Essential to Pathogenesis in a Drosophila Model of Spinobulbar Muscular Atrophy

Native Functions of the Androgen Receptor are Essential to Pathogenesis in a Drosophila Model of Spinobulbar Muscular Atrophy

Spinobulbar muscular atrophy (SBMA) is a progressive, late-onset disease characterized by degeneration of motor neurons in the brainstem and spinal cord. The disease is caused by expansion of a polyglutamine tract in the androgen receptor (AR) and is dependent on exposure to AR ligand. The expanded polyglutamine tract confers toxic function to the protein through unknown mechanisms, although the ligand-dependent nature of SBMA suggests that the mechanism of pathogenesis may be tied to ligand-dependent alterations in AR function. However, whether toxicity is mediated by native AR function or a novel AR function is unknown. We systematically investigated ligand-dependent modifications of AR in a Drosophila model of SBMA. We demonstrate in vivo that nuclear translocation of mutant AR is necessary but not sufficient for toxicity and that DNA binding by AR is necessary for toxicity. Mutagenesis studies demonstrated that a functional AF-2 domain is essential for toxicity, a finding corroborated by a genetic screen that identified AF-2 interactors as dominant modifiers of degeneration. As proof of this principle, we perform epistasis experiments using the AR coregulator limpet, which we find modifies polyglutamine-expanded AR toxicity in an AF-2-dependent manner. In addition, we use expression profiling to examine the molecular phenotype of polyglutamine- expanded AR degeneration, revealing that expression of wild-type AR results in a molecular phenotype that is very similar to that caused by polyglutamine-expanded AR. These findings suggest that expanded-

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Inhibition Studies of the Synergistic Effect of Rosemary oil and Zinc Oxide on S41003 Ferritic Steel Corrosion in Dilute Sulphuric and Hydrochloric Acid Solutions

Inhibition Studies of the Synergistic Effect of Rosemary oil and Zinc Oxide on S41003 Ferritic Steel Corrosion in Dilute Sulphuric and Hydrochloric Acid Solutions

0.0568mm/y at 240 h. Addition of ROZ compound changed the electrochemical nature and mechanism of reaction of the acid test solutions. The corrosion rate of S41003 decreased sharply after 0% ROZ in both acids, showing similar trend in corrosion rate values at 0.5% - 2.5% ROZ with respect to exposure time due to the effective inhibiting action of ROZ compound. This observation is consistent with the OCP plot of potential vs time (Fig. 7). In the absence of ROZ compound S41003 had an OCP value of -0.066V in HCl; this value decreased to -0.083V at 876s and remained generally constant till 2700s. In H 2 SO 4 , the OCP value of S41003 started at -0.077V at 0s and decreased to -0.088V at 515s after which it remained generally constant till 2700s, signifying the dominant effect of the cathodic reaction mechanism during S41003 corrosion. Addition of ROZ compound significantly altered the active passive behavior of S41003 with a major shift in corrosion potential values to -0.024V and -0.018V in HCl and H 2 SO 4 solution. These values decreased to -0.047V at 1076s for both acids. The potential value of S41003 in HCl continued to decrease until -0.056V at 2700s while the value in H 2 SO 4 remained generally constant henceforth till 2700s. The corrosion rate plots in Figs. 6(a) and (b) shows ROZ efficiency is independent of concentration with the exception of 2.5% ROZ in HCl which attains a maximum inhibition of 98.92%. ROZ stifled the

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CHEMICAL PENETRATION ENHANCERS FOR TRANSDERMAL DRUG DELIVERY SYSTEM

CHEMICAL PENETRATION ENHANCERS FOR TRANSDERMAL DRUG DELIVERY SYSTEM

Chemical penetration enhancers are proven to increase the transport of drug across the skin layers. They show their effect by different mechanisms that depend on the chemical nature of penetration enhancer, the mechanism may include disruption of lipid bilayers of stratum corneum or extraction of intercellular protein; Keratin and thus modify the penetration ability of drugs 4 or may improve the partitioning of drug due to solvent action. Chemical penetration enhances temporarily diminish the barrier nature of skin and known to accelerate or enhance drug flux.

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A No-Holds-Barred Evolution Curriculum for Elementary and Junior High School Students

A No-Holds-Barred Evolution Curriculum for Elementary and Junior High School Students

Abstract Understanding the basic mechanism of evolution by natural selection together with examples of how it works in nature is crucial for explaining and teaching the workings of biology and ecology to young students. Dobzhansky said it best in his advice to educators of biology: “Nothing in biology makes sense except in the light of evolution. ” This premise is true at all levels of biology but especially so in the elementary years where foundations of science knowl- edge are laid. Elementary students are capable of learning cohesive and connected stories of biological principles and learning them within a no-holds-barred arena wherein concepts and processes usually reserved for high school years are taught with special care, appropriate exercises, and patient explanations. This story must include solid introductions to the fundamental principles of evolution by natural selection that are threaded within and alongside those of basic biology and ecology. This paper attempts to make the case for the inclusion of connected stories of biology in the earliest years of education and to include within that education the unifying theme of all biology and ecology studies—evolution.

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Optimal complementary auctions

Optimal complementary auctions

Consider the situation where two products are sold by the same seller, but to disjoint sets of potential buyers. Also that externalities may arise from each market outcome to the other. This paper examines the nature of the seller's optimal mechanism, and, for example in the case of positive externalities, it is shown that the allocation decision in either market depends on the highest types in both markets. The optimal mechanism can be implemented by an indirect mechanism that essentially charges winning bidders for the value of their externalities. The analysis is applied to the sale of public sector franchises including exploration and development rights for oil and gas tracts.

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Mechanistic and structural studies on myo inositol monophosphatase: the emerging target for lithium therapy

Mechanistic and structural studies on myo inositol monophosphatase: the emerging target for lithium therapy

The fact that the phosphorothioate analogues of Insl-P and 2'-AMP are processed by inositol monophosphatase, albeit slower than the phosphate versions, is another indication that inositol monophosphatase might operate via an adjacent displacement mechanism. Remembering that the first metal ion (Mg^^l) malces a strong binding interaction with the phosphate moiety of the substrate, one would expect a substantial reduction in rate with a phosphorothioate analogue due to the large size of the sulfur atom forcing the P-atom away from Mg^^l (Mn^^l in the case of 2'-AMPg) and reducing the binding affinity. However, this effect would also increase steric hindrance for an in-line attack by a nucleophile located on Mg^'^l and these two effects combined would be expected to cause a much more severe reduction in rate than is actually observed (typically 10—20% rate of hydrolysis for phosphomonoester substrate). Conversely, an adjacent attack mechanism would not encounter the second problem as the nucleophile could be positioned as to attack the phosphorothioate moiety from the opposite face to the sulfur atom.

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Comparison of damped oscillations in solar and stellar X ray
flares

Comparison of damped oscillations in solar and stellar X ray flares

Various aspects of stellar flares, including power super-flares seemed to be similar to those of solar flares (e.g., Aschwanden et al. 2008; Maehara et al. 2012). The similarity in solar and stellar flares, including the QPPs may give us hints to understand the nature of the flares and associated oscillations, as well as coronal plasma properties for various stars including the Sun (Balona et al. 2015; Chang et al. 2015). In particular, properties of oscillating loops could be estimated by applying an appropriate model to the frequency and amplitude modulation of the perturbation, which are independent on the sharpness and strength of the sources. Particularly, stellar X-ray flares can provide proper parameters such as the emission measure, temperature, abundance, and density of the flaring loops (e.g., Raassen et al. 2007; Pandey & Karmakar 2015), which are essential for the indirect determination of the coronal magnetic field strength. First attempts to use QPP for stellar coronal seismology have been made by Mitra-Kraev et al. (2005); Pandey & Srivastava (2009); Anfinogentov et al. (2013); Srivastava et al. (2013).

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The challenges facing the eastern African community in conflict intervention: a study of eastern African standby force (EASF) as regional security mechanism

The challenges facing the eastern African community in conflict intervention: a study of eastern African standby force (EASF) as regional security mechanism

EASFCOM suffers from weak bureaucratic processes and management systems poor information technologies; inadequate physical infrastructure; a lack of professional and motivated personnel; weak reputation, presence, and reach; and inadequate sources of funds. The force lacks hi-tech equipments for information gathering and collection. As a result the force`s early warning mechanism is very poor. It`s not able to efficiently monitor the volatile situation of its member states. With poor pay packages, the institutions becomes a transit camp for the professionals. They leave the institution after gathering the relevant work experience for the high-end organizations. As observed by CD that these civilians are very important for the institutional growth. But the rate at which they exit the force is quite alarming especially after acquiring relevant work experience. The EASF should consider giving them relatively good pay packages. This is bad for the growth of its various departments since the personnel with the know-how are not there to provide the expertise needed. Intervention missions would pose particular institutional challenges to the force at each stage of a mission‘s life cycle (i.e., planning, deployment, operations, and withdrawal). In the field, teams of qualified senior leaders, including the special representative, force commander, police commissioner and chief administrator are difficult to assemble and retain.

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Mechanism and Cyclic Voltammetry of Cu(en)2(ClO4)2 in Aqueous 0.2MNaClO4

Mechanism and Cyclic Voltammetry of Cu(en)2(ClO4)2 in Aqueous 0.2MNaClO4

measurements of different solvent activity. More recently, polarographic , kinetic and voltammetric results of the reductive cleavage of chlorine from 6- chloronicotinic acid on mercury electrode shows CECE process [27]. Most recently, a mechanism similar and related is the study of complexes of Cu(en) 2 X 2 .nH 2 O (n=0,for X=ClO 4 - , NO 3 - , SCN - and n=1 for Br - ) in some nonaqueous solvents[14].

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The nature and purpose of the corporation: A roundtable discussion

The nature and purpose of the corporation: A roundtable discussion

SM: That hasn’t been adequately theorised. How the argument tends to work is through a reading of John Rawls (1999). Just as Rawls established an argument for the social contract in society as a whole, we can imagine the stakeholders of the corporation in much the same way (see Freeman, 1994; Sacconi, 2006). So let’s imagine you’re a stakeholder of a company but you don’t know whether you’re an employee, a supplier, a customer, a shareholder, a lender, a member of the local community, etc. You don’t know what stake you’re going to have so what rules would you agree on with respect to the just distribution of corporate wealth? One of the main problems with this juxtaposition is precisely what you’ve put your finger on: there isn’t really a state of nature outside a single organisation within which all stakeholders might be considered formally equal. In social contract theory, citizens have a formally equal status which usually compels them to unite in the form of a state. I don’t think such an original equality can be theorised with respect to corporate stakeholders.

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Metallographic Study of Ayurvedic Bhasmas- An Analytical Study of Swarna Makshika (Chalcopyrite)

Metallographic Study of Ayurvedic Bhasmas- An Analytical Study of Swarna Makshika (Chalcopyrite)

At first the surface of the sample was made plain and smooth with the help of a specially designed motor driven emery belt. During the grinding, water was added frequently to facilitate to lower the temperature of the grinding surface, which may alter the nature of the grain of the sample. Grinding was done till the flat appearance of the sample. Then the sample was washed thoroughly with soap and water.

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Prevalence of Musculoskeletal Injuries among Adolescent Recreational Netballers in Kwa-Zulu Natal, South Africa

Prevalence of Musculoskeletal Injuries among Adolescent Recreational Netballers in Kwa-Zulu Natal, South Africa

The players’ lower extremities experienced the most injury, which confers with previous literature that indicated problems in the lumbar hip complex, knee joint, ankle and foot [2,5,6]. The most vulnerable anatomical site of acute injury in the present study was the knee, which differs from the previous studies, which indicated the ankle joint as the most common injured site [8,9]. Most players who sustained acute knee injuries cited poor landing as the primary mechanism of injury. This finding corresponds with Stuelcken et al. [2]. Single leg landing, which is common in netball, produces a large valgus force on the knee in the frontal plane, facilitating medial deviation of the tibia away from the femur [2], which can tear the medial collateral ligament and medial meniscus [9]. It is recommended that netball players be taught Saunders et al. therapeutic intervention programme, which emphasizes proper landing technique that has been reported to cause significant reduction in the incidence of ankle and knee injuries among adolescence netballers after the implementation [5].

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