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Recent advances in sensor technology and computing capabilities have enabled the creation of data-driven models that can support real-time decision making. Such a decision aid can allow for predictive maintenance (PdM) to be undertaken on a much greater scale in manufacturing plants. PdM includes data-driven prognostics and health management (PHM). A key element in developing prognostic models involves the acquisition of high-quality data, traditionally achieved through feature extraction methods to distill meaningful insights from extensive and noisy datasets. However, such methods may not handle noisy data well or address measurement errors adequately, potentially resulting in extracted features that inadequately represent the degradation process as a machine approaches failure or fault. Also, effects of sensor types on the feature extraction and prediction model have not been much explored yet. To overcome this limitation, we proposed a solution which involves dynamic feature extraction where a statistical penalty is introduced to mitigate the influence of noisy statistical features within a monotonic trend. Subsequently, the features extracted using this method are utilized to construct a health indicator (HI). Leveraging historical HI values, a probabilistic regression model may be used to forecast the time to failure (TTF) of rotating machinery with uncertainty propagation. To validate the proposed method, acceleration data were collected from rotating machinery for several run-to-failure cases. The proposed method is demonstrated to provide excellent forecasts of TTF for both accelerometer types. [ABSTRACT FROM AUTHOR]

Biological systems are homochiral, raising the question of how a racemic mixture of prebiotically synthesized biomolecules could attain a homochiral state at the network level. Based on our recent results, we aim to address a related question of how chiral information might have flowed in a prebiotic network. Utilizing the crystallization properties of the central ribonucleic acid (RNA) precursor known as ribose-aminooxazoline (RAO), we showed that its homochiral crystals can be obtained from its fully racemic solution on a magnetic mineral surface due to the chiral-induced spin selectivity (CISS) effect [Ozturk et al., arXiv:2303.01394 (2023)]. Moreover, we uncovered a mechanism facilitated by the CISS effect through which chiral molecules, such as RAO, can uniformly magnetize such surfaces in a variety of planetary environments in a persistent manner [Ozturk et al., arXiv:2304.09095 (2023)]. All this is very tantalizing because recent experiments with tRNA analogs demonstrate high stereoselectivity in the attachment of L-amino acids to D-ribonucleotides, enabling the transfer of homochirality from RNA to peptides [Wu et al., J. Am. Chem. Soc. 143, 11836 (2021)]. Therefore, the biological homochirality problem may be reduced to ensuring that a single common RNA precursor (e.g., RAO) can be made homochiral. The emergence of homochirality at RAO then allows for the chiral information to propagate through RNA, then to peptides, and ultimately through enantioselective catalysis to metabolites. This directionality of the chiral information flow parallels that of the central dogma of molecular biology—the unidirectional transfer of genetic information from nucleic acids to proteins [F. H. Crick, in Symposia of the Society for Experimental Biology, Number XII: The Biological Replication of Macromolecules, edited by F. K. Sanders (Cambridge University Press, Cambridge, 1958), pp. 138-163; and F. Crick, Nature 227, 561 (1970)]. [ABSTRACT FROM AUTHOR]

Society's consumption of natural resources and the impact of industrial activities on the environment have gained increasing attention over the last several decades. This paper provides a historical perspective on the origins of the environmental movement and its connection to industrial systems. Then, recent research related to product design, process improvement and change, green manufacturing planning, and the circular economy are described. With respect to product design, topics such as material selection and component light-weighting are considered. For process-related research, efforts such as operation changes and equipment design for reduced energy consumption are discussed. For manufacturing planning, new developments in process planning and production scheduling are highlighted that consider environmental performance. The concept of circular economy is examined critically, with particular emphasis placed on closing materials loops via recycling and remanufacturing. The paper concludes with a discussion of challenges and opportunities to achieve the goal of industrial sustainability. [ABSTRACT FROM AUTHOR]

Abstract In the U.S., bioenergy accounts for about 50% of the total renewable energy that is generated. Biomass may be used as a source of energy in a variety of ways. Using forest residues, which would normally be treated as waste, in a co-firing power plant application is one strategy for utilizing biomass. Every stage in the life cycle of using forest residues (e.g., growing biomass, harvesting biomass, transporting biomass, and co-firing with coal) has consequences in terms of the three dimensions of sustainability: economy, environment, and society. An integrated sustainability model (ISM) using system dynamics is developed for a bioenergy system to understand how changes in the bioenergy system influence environmental measures, economic development, and social impacts. Exogenous factors such as population growth, land-use change (LUC) patterns, and renewable energy policy are considered by the ISM. Predictions, such as soil carbon sequestration, greenhouse gas savings, monetary gain, and employment, can be made for a given temporal and spatial scale. Different policy scenarios varying the bioenergy share of the total electricity generation were identified and examined via the ISM. The results of the scenario analysis indicate that an increase in the bioenergy share of the total electricity generation will stimulate the bioenergy market for bio-power. Model projections provide comprehensive insights to key stakeholders and policy makers for supporting decision-making regarding bioenergy development. Highlights • An integrated sustainability model is proposed for a bioenergy system. • System dynamics is used to predict environmental and socio-economic impacts. • An increase in bioenergy share can stimulate the bioenergy market for bio-power. [ABSTRACT FROM AUTHOR]

Cyanamide is a prebiotically plausible compound that has previously been invoked as a phosphate activating agent. However, its reactions with phosphate monoesters are very slow and tend to be low yielding. We now report a fast and efficient phosphate activation reaction using cyanamide in the presence of glyoxylate or pyruvate. These simple 2-oxoacid salts are shown to function as catalysts and in an optimised system, adenosine-3′-phosphate was converted to adenosine-2′,3′-cyclic phosphate in 95% yield. [ABSTRACT FROM AUTHOR]

Non-enzymatic oligomerization of activated ribonucleotides leads to ribonucleic acids that contain a mixture of 2′,5′- and 3′,5′-linkages, and overcoming this backbone heterogeneity has long been considered a major limitation to the prebiotic emergence of RNA. Herein, we demonstrate non-enzymatic chemistry that progressively converts 2′,5′-linkages into 3′,5′-linkages through iterative degradation and repair. The energetic costs of this proofreading are met by the hydrolytic turnover of a phosphate activating agent and an acylating agent. With multiple rounds of this energy-dissipative recycling, we show that all-3′,5′-linked duplex RNA can emerge from a backbone heterogeneous mixture, thereby delineating a route that could have driven RNA evolution on the early earth. [ABSTRACT FROM AUTHOR]

Non-enzymatic oligomerization of activated ribonucleotides leads to ribonucleic acids that contain a mixture of 2′,5′- and 3′,5′-linkages, and overcoming this backbone heterogeneity has long been considered a major limitation to the prebiotic emergence of RNA. Herein, we demonstrate non-enzymatic chemistry that progressively converts 2′,5′-linkages into 3′,5′-linkages through iterative degradation and repair. The energetic costs of this proofreading are met by the hydrolytic turnover of a phosphate activating agent and an acylating agent. With multiple rounds of this energy-dissipative recycling, we show that all-3′,5′-linked duplex RNA can emerge from a backbone heterogeneous mixture, thereby delineating a route that could have driven RNA evolution on the early earth. [ABSTRACT FROM AUTHOR]

Linear dichroism provides information on the orientation of chromophores part of, or bound to, an orientable molecule such as DNA. For molecular alignment induced by hydrodynamic shear, the principal axes orthogonal to the direction of alignment are not equivalent. Thus, the magnitude of the flow-induced change in absorption for light polarized parallel to the direction of flow can be more than a factor of two greater than the corresponding change for light polarized perpendicular to both that direction and the shear axis. The ratio of the two flow-induced changes in absorption, the dichroic increment ratio, is characterized using the orthogonal orientation model, which assumes that each absorbing unit is aligned parallel to one of the principal axes of the apparatus. The absorption of the alienable molecules is characterized by components parallel and perpendicular to the orientable axis of the molecule. The dichroic increment ratio indicates that for the alignment of DNA in rectangular flow cells, average alignment is not uniaxial, but for higher shear, as produced in a Couette cell, it can be. The results from the simple model are identical to tensor models for typical experimental configurations. Approaches for measuring the dichroic increment ratio with modern dichrometers are discussed. [ABSTRACT FROM AUTHOR]

Background: Our study was performed to evaluate the image quality of 3 T MR wrist arthrograms with attention to ulnar wrist structures, comparing image quality of isotropic 3D proton density fat suppressed turbo spin echo (PDFS TSE) sequence versus standard 2D 3 T sequences as well as comparison with 1.5 T MR arthrograms.Methods: Eleven consecutive 3 T MR wrist arthrograms were performed and the following sequences evaluated: 3D isotropic PDFS, repetition time/echo time (TR/TE) 1400/28.3 ms, voxel size 0.35x0.35x0.35 mm, acquisition time 5 min; 2D coronal sequences with slice thickness 2 mm: T1 fat suppressed turbo spin echo (T1FS TSE) (TR/TE 600/20 ms); proton density (PD) TSE (TR/TE 3499/27 ms). A 1.5 T group of 18 studies with standard sequences were evaluated for comparison. All MR imaging followed fluoroscopically guided intra-articular injection of dilute gadolinium contrast. Qualitative assessment related to delineation of anatomic structures between 1.5 T and 3 T MR arthrograms was carried out using Mann-Whitney test and the differences in delineation of anatomic structures among each sequence in 3 T group were analyzed with Wilcoxon signed-rank test. Quantitative assessment of mean relative signal intensity (SI) and relative contrast measurements was performed using Wilcoxon signed-rank test.Results: Mean qualitative scores for 3 T sequences were significantly higher than 1.5 T (p < 0.01), with isotropic 3D PDFS sequence having highest mean qualitative scores (p < 0.05). Quantitative analysis demonstrated no significant difference in relative signal intensity among the 3 T sequences. Significant differences were found in relative contrast between fluid-bone and fluid-fat comparing 3D and 2D PDFS (p < 0.01).Conclusions: 3D isotropic PDFS sequence showed promise in both qualitative and quantitative assessment, suggesting this may be useful for MR wrist arthrograms at 3 T. Primary reasons for diagnostic potential include the ability to make reformations in any obliquity to follow the components of ulnar side wrist structures including triangular fibrocartilage complex. Additionally, isotropic imaging provides thinner slice thickness with less partial volume averaging allowing for identification of subtle injuries. [ABSTRACT FROM AUTHOR]

Either to sustain autotrophy, or as a prelude to heterotrophy, organic synthesis from an environmentally available C1 feedstock molecule is crucial to the origin of life. Recent findings augment key literature results and suggest that hydrogen cyanide--"Blausäure"--was that feedstock. [ABSTRACT FROM AUTHOR]

Organische Synthesen aus einer in der Umwelt verfügbaren C1-Quelle, ob nun zur Aufrechterhaltung von Autotrophie oder als Auftakt von Heterotrophie, sind ein zentraler Aspekt in der Frage nach dem Ursprung des Lebens. Neuere Befunde ergänzen Schlüsselergebnisse aus der Literatur und legen nahe, dass Blaus.ure (HCN) dieses Ausgangsmolekül war. [ABSTRACT FROM AUTHOR]

The article discusses the origin of biological homochirality by crystallization of an RNA precursor on a magnetic surface. It discusses the importance of achieving homochirality for a high-yielding prebiotic network capable of producing functional polymers, it also studies d the spin-selective crystallization of racemic ribo-aminooxazoline (RAO), an RNA precursor, on magnetite (Fe3O4) surfaces and which demonstrated prebiotically plausible way of achieving system-level homochirality.

A method for obtaining fluorescence polarization data from an instrument designed to measure circular and linear dichroism is compared with a previously reported approach. The new method places a polarizer between the sample and a detector mounted perpendicular to the direction of the incident beam and results in determination of the fluorescence polarization ratio, whereas the previous method does not use a polarizer and yields the fluorescence anisotropy. A similar analysis with the detector located axially with the excitation beam demonstrates that there is no frequency modulated signal due to fluorescence polarization in the absence of a polarizer. [ABSTRACT FROM AUTHOR]

Soon after the origin of RNA-based life, depletion of prebiotically synthesised ribonucleotides would have driven the evolution of a biosynthetic pathway to these key building blocks. Ribozyme-catalysed nucleosidation-the key biosynthetic step-requires that ribose and the nucleobases are produced by abiotic chemistry and are relatively stable to the conditions of their synthesis. The most plausible prebiotic synthesis of sugars involves photoreduction of cyanohydrins by hydrogen sulphide in the presence of copper(I) cyanide, and we therefore subjected ribose to these conditions whereupon it was partially converted to 2-deoxyribose. Furthermore, a derivative of uracil is reduced under similar conditions to thymine. Thus, DNA biosynthetic precursors can be formed abiotically from those of RNA allowing for an early evolutionary transition to life based on RNA and DNA. [ABSTRACT FROM AUTHOR]

Selection of bacterial strains for resistance to antimicrobial agents may affect fitness; and fluoroquinolone resistance has been shown to affect fitness of aerobic and facultative bacteria. The impact on bacterial fitness of resistance selection to three fluoroquinolones was examined in three wild-type strains of Clostridium perfringens: ATCC 13124, ATCC 3626, and NCTR. Selection for resistance to norfloxacin, ciprofloxacin, and gatifloxacin affected the fitness of nine mutant strains differently. In a series of pure cultures grown in the absence of drugs, the growth of each of the mutants was comparable to that of the corresponding wild type. In competition experiments between mutants and isogenic wild types, however, some of the mutants were less fit. The fitness of ciprofloxacin-resistant mutants was comparable for all three strains, but two gatifloxacin-resistant mutants and one norfloxacin-resistant mutant were significantly less fit than the corresponding wild types. We conclude that both the genetic background of the strain and the fluoroquinolone which induced resistance affected the fitness of the resistant mutants. This is the first time that the effect on fitness of resistance to antimicrobial agents has been measured for C. perfringens. [ABSTRACT FROM AUTHOR]

The quinolones are an important group of synthetic antimicrobial drugs used for treating bacterial diseases of humans and animals. Microorganisms transform antimicrobial quinolones (including fluoroquinolones) and the pharmacologically related naphthyridones, pyranoacridones, and cinnolones to a variety of metabolites. The biotransformation processes involve hydroxylation of methyl groups; hydroxylation of aliphatic and aromatic rings; oxidation of alcohols and amines; reduction of carboxyl groups; removal of methyl, carboxyl, fluoro, and cyano groups; addition of formyl, acetyl, nitrosyl, and cyclopentenone groups; and cleavage of aliphatic and aromatic rings. Most of these reactions greatly reduce or eliminate the antimicrobial activity of the quinolones. [ABSTRACT FROM AUTHOR]

A recent synthesis of activated pyrimidine ribonucleotides under prebiotically plausible conditions relied on mixed oxygenous and nitrogenous systems chemistry. As it stands, this synthesis provides support for the involvement of RNA in the origin of life, but such support would be considerably strengthened if the sugar building blocks for the synthesis-glycolaldehyde and glyceraldehyde-could be shown to derive from one carbon feedstock molecules using similarly mixed oxygenous and nitrogenous systems chemistry. Here, we show that these sugars can be formed from hydrogen cyanide by ultraviolet irradiation in the presence of cyanometallates in a remarkable systems chemistry process. Using copper cyanide complexes, the process operates catalytically to disproportionate hydrogen cyanide, first generating the sugars and then sequestering them as simple derivatives. [ABSTRACT FROM AUTHOR]

Purpose |!|#8211; The purpose of this paper is to estimate the extent of |!|#34;over-qualification|!|#34; (i.e. holding a qualification which is above that required to gain entry to the job being done) and |!|#34;skills under-utilisation|!|#34; (i.e. being in a job which does not make use of the knowledge and skills possessed) in the United Kingdom and to examine whether these conditions are correlated with age. Design/methodology/approach |!|#8211; The paper makes use of the 2006 Skills Survey. Cross tabulations of both conditions with age are produced and binomial probit estimates of both conditions are reported. Findings |!|#8211; It is estimated that 38 per cent are over qualified; 15 per cent are in jobs which do not make use of the knowledge and skills they possess; and age is correlated with the probability of being over qualified but not with the condition of under-utilising the knowledge and skills possessed. Social implications |!|#8211; Skills policy in the United Kingdom focuses almost exclusively upon increasing the supply of more highly qualified individuals. Given the extent of over-qualification and skills under-utilisation demonstrated in the paper, more effort should be made by policy makers to design and implement policies which increase the demand for highly skilled labour. Originality/value |!|#8211; The paper answers three questions: How prevalent are qualification mismatches? How prevalent are skills mismatches? To what extent are the two conditions of being over-qualified and being in a job which does not offer scope to make use of the knowledge and skills possessed correlated with age? [ABSTRACT FROM AUTHOR]

ABSTRACT A single-beam spectrometer equipped with a photoelastic modulator can be configured to measure a number of different parameters useful in characterizing chemical and biochemical materials including natural and magnetic circular dichroism, linear dichroism, natural and magnetic fluorescence-detected circular dichroism, and fluorescence polarization anisotropy as well as total absorption and fluorescence. The derivations of the mathematical expressions used to extract these parameters from ultraviolet, visible, and near-infrared light-induced electronic signals in a dichrometer assume that the dichroic signals are sufficiently small that certain mathematical approximations will not introduce significant errors. This article quantifies errors resulting from these assumptions as a function of the magnitude of the dichroic signals. In the case of linear dichroism, improper modulator programming can result in errors greater than those resulting from the assumption of small signal size, whereas for fluorescence polarization anisotropy, improper modulator phase alone gives incorrect results. Modulator phase can also impact the values of total absorbance recorded simultaneously with linear dichroism and total fluorescence. Chirality 24:706-717, 2012. © 2012 Wiley Periodicals, Inc.† [ABSTRACT FROM AUTHOR]

In this article Sutherland surveys over the period of the last 40 years (the length of an average full academic career) the changes which have occurred to the departmental structures and procedures in the teaching of and research into English Literature in British universities. He perceives a marginalization of the English department in the overall university organization and a set of pressures, which he conceives as deleterious: the introduction of an externally based inspectorial regime, professionalization (and a concomitant proletarianization), conference culture (and its associated jargons), field-specialism, optionalization and customerization. The conclusions reached are gloomy, if admittedly subjective. [ABSTRACT FROM PUBLISHER]

Prior to the Internet, information available to the public on white extremist groups, such as the United White Knights of the Ku Klux Klan, came from news events which prevented these groups from controlling the information presented to the public about themselves, their organization, ideals, or goals. But the Internet has allowed these groups to develop websites through which they can directly dictate their image to vast audiences. The purpose of this study was to explore the relationship between political orientation and fundamental Christian beliefs and agreement with the values of a white extremist group, as presented by the United White Knights on their website. Results suggest political orientation and Christian fundamental beliefs are significantly related, but not as strong as expected, to agreement with the values of the United White Knights: as levels of conservatism and Christian orthodoxy increase, the more likely a person is to be in agreement with the group's values/beliefs. These findings support the notion that some Klan organizations, such as the United White Knights, are taking steps to rebrand their image into a more mainstream organization with an ideology similar to white, religious and political conservatives. [ABSTRACT FROM PUBLISHER]

Daidzein (4′,7-dihydroxyisoflavone), a phytoestrogen found in soybeans mainly in the form of its glycoside daidzin, is metabolized by colonic bacteria to compounds with altered estrogenic activities, which may affect human health. Antibacterial agents used for the treatment of infections can alter the composition of bacterial populations in the colon and therefore can affect daidzein metabolism. To rapidly detect the effects of different concentrations of antibiotics on daidzein metabolism by colonic bacteria of monkeys and identify the subpopulation involved in daidzein metabolism, Etest strips containing antibacterial agents from three classes (tetracyclines, fluoroquinolones, and β-lactams) were used to eliminate the colonic bacteria that were susceptible to 0-32 μg/ml of each antibacterial agent and test the surviving bacteria for their ability to metabolize daidzein. The metabolism of daidzein by the colonic microflora was measured before and after the colonic bacterial population was exposed to antibacterial agents. The metabolites were detected by high performance liquid chromatography and mass spectrometry after incubation of the cultures for various times. Exposure of colonic microflora to antibiotics had various effects on daidzein metabolism. Tetracycline completely removed the bacteria metabolizing daidzein, metabolism of daidzein was not changed in cultures of bacteria after ceftriaxone treatment, and ciprofloxacin enriched for the bacteria metabolizing daidzein. In liquid cultures treated with various concentrations of ciprofloxacin, 4 μg/ml of ciprofloxacin favored the growth of bacteria that metabolized daidzein. This is the first time in which the Etest has been used to show that, whereas some antibiotics eliminate phytoestrogen-metabolizing bacteria in colonic microflora, others enrich them by eliminating the non-metabolizing strains in the population. [ABSTRACT FROM AUTHOR]

A variety of macromolecules and small molecules--(oligo)nucleotides, proteins, lipids and metabolites-- are collectively considered essential to early life. However, previous schemes for the origin of life--e.g. the 'RNA world' hypothesis--have tended to assume the initial emergence of life based on one such molecular class followed by the sequential addition of the others, rather than the emergence of life based on a mixture of all the classes of molecules. This view is in part due to the perceived implausibility of multi-component reaction chemistry producing such a mixture. The concept of systems chemistry challenges such preconceptions by suggesting the possibility of molecular synergism in complex mixtures. If a systems chemistry method to make mixtures of all the classes of molecules considered essential for early life were to be discovered, the significant conceptual difficulties associated with pure RNA, protein, lipid or metabolism 'worlds' would be alleviated. Knowledge of the geochemical conditions conducive to the chemical origins of life is crucial, but cannot be inferred from a planetary sciences approach alone. Instead, insights from the organic reactivity of analytically accessible chemical subsystems can inform the search for the relevant geochemical conditions. If the common set of conditions under which these subsystems work productively, and compatibly, matches plausible geochemistry, an origins of life scenario can be inferred. Using chemical clues from multiple subsystems in this way is akin to triangulation, and constitutes a novel approach to discover the circumstances surrounding the transition from chemistry to biology. Here, we exemplify this strategy by finding common conditions under which chemical subsystems generate nucleotides and lipids in a compatible and potentially synergistic way. The conditions hint at a post-meteoritic impact origin of life scenario. [ABSTRACT FROM AUTHOR]

Can we look at contemporary biology and couple this with chemical insight to propose some plausible mechanisms for the origin of life on the planet? In what follows, we examine some promising chemical reactions by which the building blocks for nucleic acids might have been created about a billion years after the Earth formed. This could have led to self-assembling systems that were based on an all-RNA metabolism, where RNA is both catalytic and informational. We consider the breadth of RNA enzymes presently existing in biology, and to what extent these might have covered a wider range of chemistry in the RNA world. Ultimately, the RNA world would probably have given way to protein-based life quite quickly, and the origins of peptidyl transferase activity are discussed below. [ABSTRACT FROM AUTHOR]

The origins of life represent one of the most fundamental chemical questions being addressed by modern science. One of the longstanding mysteries of this field is what series of chemical reactions could lead to the molecular biologists dream; a pool of homochiral nucleotides? Here we summarize those results we consider to be historically important and outline our recently published research aimed at understanding the chemoselective origins of the canonical ribonucleotides. 1 Introduction 1.1 Nucleotides: What's the Problem? 2 Synthesis of Activated Pyrimidines 2.1 Pyrimidine Elaboration by Cyanovinylation 2.2 Photochemical Epimerization and Cytidine to Uridine Conversion 2.3 Urea-Mediated Phosphoryl Transfer and Intramolecular Rearrangement 2.4 Pyrimidine Photosanitization 3 Chemoselective Purine Glycosylation 4 Future Scope for Investigation 5 Conclusion [ABSTRACT FROM AUTHOR]

Background: Transhiatal robot-assisted total esophagectomy (RE) has gained acceptance as a minimally invasive procedure with several clinical benefits. In this report, the authors describe their experience with the incidence of incarcerated hiatal hernia after RE. Methods: Between March 2007 and July 2009, 36 patients underwent RE at the authors' institution. A retrospective chart review was performed, and data were abstracted including gender, age, weight at surgery, presenting symptoms, pathologic diagnosis, operative time, estimated blood loss, mortality, and postoperative complications. Results: The study cohort consisted of 28 men and 8 women undergoing RE. Their average age was 65.4 ± 10.5 years, and their mean body weight was 86.2 ± 24.8 kg at surgery. A review of medical records indicated that 7 (19.4%) of the 36 patients had postoperative incarcerated hiatal hernias. Two of these patients had experienced two episodes of incarceration, which required reoperation. One patient died of complications related to hernia repair. Six (85.7%) of 7 patients had a preexisting diagnosis of hiatus hernia which was significantly higher in comparison to the incidence of this complication within the group of 29 patients without post-operative hernia incarcerations (11 of 29, 37.9%; Fisher's exact p = 0.04). Conclusions: The results indicate that postoperative incarcerated hiatal hernia after RE is an infrequently reported, albeit serious, complication. A preexisting hiatal hernia may put patients at a higher risk of incarceration. According to the authors' experience, a primary closure and reinforcement with mesh sutured to the gastric wall is recommended as a preventive measure. Diligent follow-up evaluation with regular computed tomography (CT) scans investigating likelihoods for incarceration is advisable, especially for patients with preexisting hernias. [ABSTRACT FROM AUTHOR]

The recent development of a sequential, high-yielding route to activated pyrimidine nucleotides, under conditions thought to be prebiotic, is an encouraging step toward the greater goal of a plausible prebiotic pathway to RNA and the potential for an RNA world. However, this synthesis has led to a disparity in the methodology available for stepwise construction of the canonical pyrimidine and purine nucleotides. To address this problem, and further explore prebiotically accessible chemical systems, we have developed a high-yielding, aqueous, one-pot, multicomponent reaction that tethers masked-sugar moieties to prebiotically plausible purine precursors. A pH-dependent three-component reaction system has been discovered that utilizes key nucleotide synthons 2-aminooxazole and 5-aminoimidazoles, which allows the first divergent purine/pyrimidine synthesis to be proposed. Due to regiospecific aminoimidazole tethering, the pathway allows N9 purination only, thus suggesting the first prebiotically plausible mechanism for regiospecific N9 purination. [ABSTRACT FROM AUTHOR]

Cultures of Mycobacterium vanbaalenii strain PYR-1 in a liquid medium were exposed to the toxic environmental contaminant acridine (260 μM). After incubation for 7 d, the cultures were extracted with ethyl acetate. Metabolites were purified using high-performance liquid chromatography and analyzed by mass spectrometry and 1H nuclear magnetic resonance spectroscopy. Four metabolites, 9,10-dihydroacridine, 4-hydroxyacridine, acridine cis-1,2-dihydrodiol, and acridin-9(10H)-one, were identified. [ABSTRACT FROM AUTHOR]

Abstract: Sustainability recognizes the interdependence of ecological, social, and economic systems – the three pillars of sustainability. The definition of corporate social responsibility (CSR) often advocates ethical behavior with respect to these systems. As more corporations commit to sustainability and CSR policies, there is increasing pressure to consider social impacts throughout the supply chain. This paper reviews metrics, indicators, and frameworks of social impacts and initiatives relative to their ability to evaluate the social sustainability of supply chains. Then, the relationship between business decision-making and social sustainability is explored with attention initially focused on directly impacting national level measures. A general strategy for considering measures of social sustainability is proposed, and a variety of indicators of CSR are described. Several of these indicators are then employed in an example to demonstrate how they may be applied to supply chain decision-making. [Copyright &y& Elsevier]

Abstract: Five tetranortriterpenoids, domesticulide A–E (1–5), were isolated from seeds of Lansium domesticum Corr. together with 11 known triterpenoids (6–16). Their structures were elucidated by analysis of their spectroscopic data. Compounds 2, 3, 4, 7, 8, 10, 11, and 15 showed antimalarial activity against Plasmodium falciparum with IC50’s of 2.4–9.7μg/ml. [Copyright &y& Elsevier]

Cultures ofUmbelopsis ramanniana(=Mucor ramannianus) were grown in fluid Sabouraud medium for 3 days, dosed with 0.23 mM benzo[f]quinoline, benzo[h]quinoline, or phenanthridine (benzo[c]quinoline), and incubated for another 18 days. Cultures were extracted and metabolites (66-75% of the UV absorbance) were separated by high-performance liquid chromatography. They were identified by mass spectrometry and nuclear magnetic resonance spectroscopy. Benzo[f]quinoline was metabolized to benzo[f]quinolinetrans-7,8-dihydrodiol, benzo[f]quinolineN-oxide, and 7-hydroxybenzo[f]quinoline, benzo[h]quinoline was metabolized to benzo[h]quinolinetrans-5,6-dihydrodiol, benzo[h]quinolinetrans-7,8-dihydrodiol, and 7-hydroxybenzo[h]quinoline, and phenanthridine was metabolized to phenanthridineN-oxide and phenanthridin-6(5H)-one. At least one of the metabolites produced from each compound was mutagenic and could not be considered detoxified. [ABSTRACT FROM AUTHOR]

This article reviews the advantages and disadvantages of the many pharmacologic treatments for glucose control and hyperglycemia in type 2 diabetes. Self-monitoring of blood glucose is an integral component of diabetes therapy and should always be included in the management plan. A registered dietitian familiar with diabetes should individualize medical nutrition therapy, preferably. A regular physical activity program is recommended for all patients with diabetes who are capable of participating. When a monotherapy fails, combine drugs with different mechanisms of action to achieve an additive effect. The combination of sulfonylurea and metformin has proven effective in many studies. One showed that initial treatment with glyburide/metformin improved glycemic control better than either glyburide or metformin monotherapy.

This article discusses the critical factors that practitioners can address to help depressed patients continue with the treatment and achieve the best outcome. It describes the different therapeutic options for depression, such as pharmacotherapy, combined pharmacotherapy and psychiatric consultation, herbal and nutritional products, and physical activities. Guidelines for medicating patients and setting expectations are presented, as well as an outline of the different factors in drug selection.

A mechanistic model for the prediction of tapping torque and axial force is developed. The model is capable of predicting tapping torque and axial force resulting from chip formation and tool flank/workpiece friction under various machining conditions, including dry tapping and tapping with different cutting fluids. Extensive tests on tapping torque and axial force measurements are conducted to verify the predictive model. Characteristics of the measured tapping loads are studied. It is found that the total tapping load consists of a base load and a chip packing load. The base load results from chip formation and tool/workpiece friction. The predicted tapping load is found to be in good agreement with measured base load. The chip packing load is the result of chip clogging in the flutes, and is random in nature. The chip packing load may be many times that of the base load, depending on tap geometries and the machining conditions. Factors causing severe chip clogging and excessive torque leading to tap breakage are also reported. [Copyright &y& Elsevier]

The residues located at the carboxyl terminus of helix D in interleukin-7 (IL-7) have previously been targeted as important for recruitment and binding to the γ chain component of the IL-7 receptor (IL-7R). In this study, Trp 143 of helix D was mutated to His, Phe, Tyr and Pro and these mutants, along with a W143A mutant previously described, were studied to determine the effects on activation of DNA synthesis and binding affinity to IL-7R positive 2E8 cells. The W143F and W143Y mutants were similar to wild type IL-7 in their binding properties and retained 85% and 74% of their activating properties, respectively. In contrast, the W143H mutant possessed a lower binding affinity and a corresponding decrease in activation, the W143A mutant possessed an over 100-fold decreased binding affinity and some residual activation activity and the W143P mutant possessed a greatly decreased binding affinity and did not activate. These results strongly suggest an aromatic residue is required at position 143 for IL-7R binding and subsequent signal transduction. [Copyright &y& Elsevier]

Profiles book collector and businessman Michael Sadleir. Hobbies of Sadleir; Apprehensions of Sadleir.

In this report, we show that a very common modification (especially in tRNA), dihydrouridine, was efficiently produced by photoreduction of the canonical pyrimidine ribonucleoside, uridine in formamide. Formamide not only acts as a solvent in this reaction, but also as the reductant. The other three components of the canonical alphabet (C, A, G) remained intact under the same conditions, suggesting that dihydrouridine might have coexisted with all four canonical RNA nucleosides (C, U, A, G) at the dawn of life. [ABSTRACT FROM AUTHOR]

Using different prebiotically plausible activating reagents, the RNA ligation yield was significantly increased in the presence of Mn(II). The mechanism of the activation reaction has been investigated using 5′-AMP as an analogue. [ABSTRACT FROM AUTHOR]

Presents a study which looked at the fungal biotransformation of 6-Nitrochrysene with Cunninghamella elegans. Information on 6-Nitrochrysene; Microbial metabolism of nitro-polycyclic aromatic hydrocarbons; Method used to conduct biotransformation experiments; Results of the study.

Presents a heuristic approach to the analysis of enzymic catalysis. Reaction of delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-alpha-aminobutyrate and delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-allyglycine catalyzed by isopenicillin N synthase isozymes; Expression; Purification; Characterization.

Focuses on the imbalance between the steady increase in the complexity of process-related technologies, and the much slower rate of increase in the sophistication of process control systems. Exploration of two avenues in which the imbalance can be attacked; Details on the avenues.

Reviews the history of psychoanalytic conceptualizations of the self. Examination of extra-clinical evidence from literature, philosophy and the social sciences for additional insights into the persistent features of the self; Characteristics of the human self in light of new insights from modern evolutionary biology.

The article discusses the role of the "sexy cover" on trade books of the late 1950s and early 1960s in the evolution of the modern British paperback novel. Topics addressed include the significance of the evolution of jacket artwork in the postwar period, the ways in which the jacket apparatus can play a leading interpretive role for the story, and the differences in the commercial and cultural origins of British and American paperbacks.

Deals with a study which analyzed mortality trends in the U.S. from 1950-1986 for the conditions that are or have been among the leading causes of death. Methods; Results; Discussion.

Provides information on the assessment of integrative systems. Information on recognizing integrative requirements; Detailed information on a taxonomy of integrative modes and intents.