bluuebunny/crossref_metadata_2025 huggingface dataset:
Scythe regulates apoptosis through modulating ubiquitin-mediated proteolysis of the Xenopus elongation factor XEF1AO
Authors: Minami Ryosuke , Shimada Masumi , Yokosawa Hideyoshi , Kawahara Hiroyuki
Published: July 2007

Scythe was originally identified as a novel Reaper-binding anti-apoptotic protein, although the mechanisms of its functions remain largely obscure. Our previous analysis revealed that Scythe can bind to a proteasomal subunit via N-terminal domains and that the domains are required for appropriate development of Xenopus embryos. In the present study, we show evidence that the N-terminus of Scythe interacts with XEF1AO, a maternal form of Xenopus laevis EF1A that was suggested to be a potential inducer of apoptosis in vertebrates, and that the binding enhances the poly-ubiquitin modification and subsequent degradation of XEF1AO. Scythe is required for degradation of XEF1AO, since immunodepletion of Scythe from embryonic extracts stabilized XEF1AO significantly. Furthermore, we show that apoptosis induced by accumulation of XEF1AO can be suppressed by co-expression of the full-length form of Scythe. These observations indicate that the proteolytic regulation of XEF1AO, mediated through Scythe, is essential to prevent inappropriate accumulation of XEF1AO and resulting apoptotic events during the course of Xenopus development.
Non-hypertensive tetraPEGylated canine haemoglobin: correlation between PEGylation, O2 affinity and tissue oxygenation
Authors: Acharya Seetharama A. , Acharya Vivek N. , Kanika Nirmala Devi , Tsai Amy G. , Intaglietta Marcos , Manjula Belur N.
Published: July 2007

TetraPEGylated canine Hb, [SP (succinimidophenyl)-PEG5K]4-canine-Hb, with PEGylation at its four reactive cysteine residues (α111 and β93) has been prepared and characterized. The hydrodynamic volume and the molecular radius of (SP-PEG5K)4-canine-Hb are intermediate to those of di- and hexaPEGylated human Hb as expected. However, the COP (colloidal osmotic pressure) of tetraPEGylated canine Hb is closer to that of hexaPEGylated human Hb than to that of diPEGylated human Hb. The O2 affinity of tetraPEGylated canine Hb is higher than that of canine Hb and comparable with that of hexaPEGylated Hb. The O2 affinity of tetraPEGylated canine Hb is not responsive to the presence of DPG (diphosphoglycerate) or chloride, but it retains almost full response to L-35, an allosteric effector that interacts at the αα-end of the central cavity. The tetraPEGylated canine Hb is vasoinactive in hamster in 10% top load infusion studies. It is also essentially non-hypertensive in an extreme exchange haemodilution protocol in hamster just as di- and hexaPEGylated human Hb. The O2 delivery by tetraPEGylated canine Hb is comparable with that of hexaPEGylated Hb but not as efficient as diPEGylated Hb. These results demonstrate that PEGylation-induced solution properties of PEG [poly(ethylene glycol)]–Hb conjugates are dictated by the level and chemistry of PEGylation and the interplay of these plays a critical role in tissue oxygenation. The studies imply the need to establish the right level (and/or pattern) of PEGylation and O2 affinity of Hb–PEG adducts in designing O2-carrying plasma volume expanders, and this remains the primary challenge in the design of PEGylated Hb as blood substitutes.
Effect of genetic resistance to gastrointestinal nematodes on plasma concentrations of insulin-like growth factor-1 and leptin in Merino sheep
Authors: Liu S. M. , Adams N. R. , Briegel J. B. , Smith T. L. , Martin G. B.
Published: July 2007

Gastrointestinal nematode infection in sheep changes the nutritional economy of the host, but little is known about the effects of infection on the hormonal systems that regulate the metabolism of the animal. This study examined two key hormones, insulin-like growth factor-1 (IGF-1) and leptin, in genetically resistant and random bred control Merino sheep in the presence or absence of nematode infection. Sixty-four 10-month-old Rylington Merino wethers, half from the parasite-resistant line and half from unselected control line, were initially maintained at two body conditions (body condition scores averaged 1.7 and 2.5) in individual pens in an animal house. The animals were kept parasite-free for 9 weeks, then ‘trickle-infected’ with Trichostrongylus colubriformis and Teladorsagia circumcincta larvae, each at a rate of 10 000 per week, for 13 weeks. Each body condition score group was subdivided into two groups at the beginning of the infection procedure and feed supply was controlled at 1× or 1.5× the maintenance metabolisable energy requirement. Plasma IGF-1 concentrations decreased marginally by day 21 of infection, then markedly by day 49, and then remained low until day 84. Plasma leptin concentrations tended to increase during the infection period. Both body condition and feed intake had significant effects on IGF-1 and leptin concentrations, and the higher concentrations were related to the good body condition or high feed intake. The parasite-resistant sheep had consistently higher concentrations of IGF-1 compared with the controls, whereas the concentrations of leptin were similar. The significant changes in IGF-1 but not leptin suggest that infection may have a more significant impact on protein anabolism, and least impact on lipid metabolism. Selection for parasite resistance appears to result in enhanced protein anabolism.
Temporal variation in cellular proliferation during recornification of mouse tail skin
Authors: Wilson R. P. , McLaughlin P. J. , Lang C. M. , Zagon I. S.
Published: July 2007

Abstract. The influence of the time of injury on subsequent epidermal regeneration is unknown. Epidermal cell proliferation of tail skin in C57BL/6J mice in response to tape stripping was followed for 7 days by radiolabeled thymidine incorporation and autoradiography. The homeostatic labelling index (LI) of the basal epidermis of unmanipulated, unwounded (control) animals was 7.6% and did not vary depending on the time of day. Tape stripping increased the LI of epidermal basal cells 110% above control values 24 h after injury. Labelling indexes of epidermal basal cells in the skin adjacent to the wounded area were 7.0%. Basal cell DNA synthesis stimulated by wounding exhibited a distinct temporal variation at 24 h postinjury, with tail skin wounded at 12.00 h found to be 275% greater than control values and elevated 78% from Lis recorded at any other time point. This temporal spike was due to the time of day at which wounding occurred rather than the time point when the LI was determined. Mice wounded at 12.00 h and terminated 27 h later (15.00 h) had Lis that were 52% greater than wounds created at 09.00 h and examined at 12.00 h the following day. Higher levels of DNA synthesis in tail skin injured at 12.00 h compared to wounding at 09.00 h was detected 12–48 h after injury. Furthermore, DNA synthesis in wounds created at 12.00 h returned to baseline levels 1–2 days earlier than tail skin wounded at 09.00 h. Investigation of other strains of mice detected differences in radiolabelling of epidermal basal cells 24 h after tape stripping at 12.00 h or 09.00 h in CD‐I and BALB/cJ mice, but not in the C3H/HeJ strain. These results indicate: (a) there is no diurnal variation in the LI of mouse tail skin under normal homeostatic conditions (b) tape stripping is a potent stimulator of basal cell turnover in the epidermis (c) the time of wounding determines the magnitude of the increase in the LI of basal cells following injury, and (d) the proliferative response to wounding of the tail is dependent on the strain of mouse.
HDAC3 is linked to cell cycle machinery in MiaPaCa2 cells by regulating transcription of skp2
Authors: Schneider G. , Reichert M. , Saur D. , Hamacher R. , Fritsch R. , Schmid R. M.
Published: July 2007

Abstract.  Objective: Histone deacetylases (HDACs) have been linked to cell cycle control in various models, involving regulation of the cyclin‐dependent kinase inhibitor p27Kip1. Results: Here, we demonstrate that HDAC inhibition by trichostatin A reduces S‐phase kinase‐associated protein 2 mRNA and protein abundance. Furthermore, in contrast to HDAC1, recruited to the skp2 promoter in the G0 phase, HDAC3 is bound in early S phase. Activating function of HDAC3 towards the skp2 gene has been validated using RNA interference techniques. siRNAs, targeting HDAC3 specifically, reduced skp2 transcription. Conclusion: These findings propose that the skp2 gene is a novel target of HDAC3, mediating cell cycle control and oncogenesis.
CD45RO: A Marker for BCR‐mediated Selection
Authors: Jackson S. M. , Harp N. , Patel D. , Henderson M. , Roy N. M. , Courtney M. A. , Johnson A. , Capra J. D.
Published: July 2007

We previously showed that IgH sequence alone minimally influenced germinal centre (GC) B‐cell survival fate. As end‐stage effector B cells are typically more mutated than founder GC B cells, we worked to develop an assay that would enrich for populations of GC B cells with progressively increasing numbers of somatic mutations, which could potentially be used as an indicator of positive selection. We targeted CD45 as it has been shown to influence activation‐induced cytidine deaminase (AID) expression. In this study, anti‐CD77 and anti‐CD45RO (RO) were used to subdivide CD19+IgD−CD38+CD77+ centroblasts (CB) and CD19+IgD−CD38+CD77− centrocytes (CC) into three contiguous RO fractions (RO−, RO+/− and RO+) and assessed whether mutation frequency and characteristics associated with selection varied with respect to increasing RO expression. Here, we show that the average number of mutations per IgVH4 transcript increased concordantly with RO for CC, but not for CB. CC also exhibited an RO‐associated increase in replacement mutations. Comparative analysis of clonally related sequences revealed that increased mutations were not due to the exclusive persistence of surface RO on highly mutated cells. RO‐expressing CC and CB pools showed increased signs of activation (CD69+) and were enriched for surface Ig+ cells. BCR‐crosslinking induced a significant increase in surface RO on total tonsillar and GC B cells, which collectively suggests that the RO‐associated increase in mutations is attributable, at least in part, to the cycling of cells that may have recently undergone BCR‐mediated selection, or are potentially in developmental transition between CC and CB stages.
Elevated MCP‐1 serum levels are associated with the H63D mutation and not the C282Y mutation in hereditary hemochromatosis
Authors: Lawless M. W. , White M. , Mankan A. K. , O’Dwyer M. J. , Norris S.
Published: July 2007

Monocyte chemoattractant protein‐1 (MCP‐1) is a major lymphocyte and inflammatory chemokine associated with persistent inflammatory states. Several abnormalities in the immune status of patients with hereditary hemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, inflammatory cytokines contributing to the pathogenesis of this disorder. The aim of this study was to assess MCP‐1 levels in patients with HH and correlate these results with HFE status and iron indexes. One hundred and thirty‐nine subjects diagnosed with HH (C282Y homozygotes = 87, C282Y/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N/N), and 18 normal subjects heterozygous for the H63D mutation served as age‐ and sex‐matched controls. Ferritin and transferrin saturation and the presence of HFE mutation status were correlated with MCP‐1 levels. Full white blood cell count analysis was also performed. We found a strongly significant decrease in MCP‐1 protein levels in the C282Y homozygotes compared with the H63D homozygotes (P = 0.0009) and C282Y/H63D heterozygotes (P = 0.002). Similarly, MCP‐1 protein levels in the C282Y homozygotes were decreased compared with the healthy controls (P = 0.00076). Furthermore, MCP‐1 serum levels were elevated in H63D patients compared with the healthy controls (P = 0.0008). This study suggests for the first time that a differential expression of MCP‐1 protein in patients with HH is associated with the specific HFE genetic component for iron overload. Therefore, these findings offer a possible explanation in the variable clinical spectrum of pathogenesis in patients with HH through abnormalities of an imbalance in the immune states of patients with HH.
The beta‐adrenoceptor antagonist propranolol counteracts anti‐inflammatory effects of isoflurane in rat endotoxemia
Authors: Boost K. A. , Flondor M. , Hofstetter C. , Platacis I. , Stegewerth K. , Hoegl S. , Nguyen T. , Muhl H. , Zwissler B.
Published: July 2007

Background:  Recent studies suggest that volatile anaesthetics have anti‐inflammatory and preconditioning properties and that beta‐adrenoceptors are involved in the signalling pathways for these effects. Concurrently, the blockade of beta‐adrenoceptors has been shown to augment the release of inflammatory mediators in response to pro‐inflammatory stimuli. We therefore aimed to investigate whether the beta‐adrenoceptor antagonist propranolol might modulate the anti‐inflammatory effects of isoflurane on the systemic and pulmonary release of pro‐inflammatory cytokines in endotoxemic rats.

Methods:  Forty anaesthetized and ventilated Sprague–Dawley rats were randomly treated as follows. Lipopolysaccharide (LPS) only (n = 8), endotoxemia with LPS [5 mg/kg, intravenously (i.v.)]. LPS‐isoflurane (n = 8): endotoxemia and continuous inhalation of 1 minimum alveolar concentration (MAC) of isoflurane. LPS‐isoflurane‐propranolol (n = 8): administration of propranolol (3 mg/kg) before continuous inhalation of isoflurane and induction of endotoxemia. LPS‐propranolol (n = 8): administration of propranolol (3 mg/kg) before endotoxemia without inhalation of isoflurane. Sham (n = 8): control‐group only with surgical preparation. After 4 h of endotoxemia, levels of tumour necrosis factor‐α (TNF‐α), interleukin‐1β (IL‐1β) and interleukin‐10 (IL‐10) in plasma and bronchoalveolar fluid (BALF) were analysed. Release of nitric oxide (NO) and amount of inducible nitric oxide synthase (iNOS) protein in alveolar macrophages was measured by Griess assay or determined by Western Blotting, respectively.

Results:  Inhalation of isoflurane reduced the release of TNF‐α (P < 0.05) and IL‐1β (P < 0.05) in plasma and IL‐1β (P < 0.05) in BALF. Co‐administration of propranolol significantly inhibited these effects. During inhalation of isoflurane, the increased release of NO and iNOS protein from alveolar macrophages was also completely inhibited by propranolol.

Conclusion:  Our results indicate for the first time, that blockade of beta‐adrenoceptors counteracts the anti‐inflammatory effects of isoflurane in endotoxemic rats.
Monitoring the neonatal brain: A survey of current practice among Australian and New Zealand neonatologists
Authors: Filan Peter M , Inder Terrie E , Anderson Peter J , Doyle Lex W , Hunt Rodney W
Published: July 2007

Aims:  There is considerable variation in the use of brain imaging and electrophysiological monitoring of encephalopathic term infants. The aims of this study were (i) to document the current practice among Australian and New Zealand neonatologists; and (ii) to identify the factors that influence local practice.

Methods:  A postal questionnaire was sent to all 152 neonatologists in Australia and New Zealand. A hypothetical scenario of an encephalopathic term infant was presented and clinicians were asked a series of questions relating to their use of magnetic resonance imaging (MRI), computed tomography, ultrasound, electroencephalography and amplitude integrated electroencephalography.

Results:  There was a 62% response rate. Twenty‐two per cent of respondents would not routinely perform an MRI brain scan in the given scenario. Limited availability, expense, logistics of transport and a lack of confidence in the ability of MRI to provide additional clinical information appear to be the main factors affecting practice. When a scan is performed, the majority of respondents (72%) perform the scan on day 5 or later. Twenty‐three per cent of respondents experience significant delays when they request an MRI scan. Regarding electrophysiological monitoring, amplitude integrated electroencephalography would be used by 62% of respondents in the given scenario.

Conclusions:  This study demonstrates that MRI is now widely used by neonatologists in Australia and New Zealand. However, local resource limitations and a lack of confidence in the utility of MRI continue to limit its use.
Hydrocarbon Substructures of Organic Molecules as Antennas and Amplifiers for External mid-IR Radiation
Authors: Jungclas Hartmut , Komarov V. V. , Popova A. M. , Schmidt L. , Stureiko I. O.
Published: July 2007

We consider organic polyatomic molecules, which contain hydrocarbon antennasi.e.substructures of identical periodically located C–H dipoles. In these antennas collective vibrational excitations (excimols) are coherently produced by resonant absorption of photons in the mid-IR energy range. The energy of an excimol is lower than the energy of the first vibrational excited state of an isolated antenna dipole and the excimol lifetime does not exceed 10-11s. The excimols are excited successively and independently in the C–H dipoles resulting in energy accumulation in the antenna. The accumulated vibrational energy can be transmitted to a trap bond, which is also forming a dipole inside the molecule, however, not acting as an antenna. The trap bond is cleaved, if the absorbed excimol energy is equal to its dissociation energy. Under certain conditions the accumulated energy can be transformed to electronic excitation of a molecular constituent resulting in molecular luminescence. The emitted luminescence photons have energies much higher than the energy of each of the IR photons, which induce an excimol. Thus the hydrocarbon antennas in organic molecules are able to work as amplifiers of external IR radiation. These intramolecular energy transmission processes complete within a time period less or equal to the excimol lifetime and thus can be referred to as super-fast compared to typical time scales calculated by statistical models. The model presented here predicts that the probabilities of the considered processes resonantly depend on the frequency and intensity of IR radiation. The presented theoretical model is supported by the results of our experimental studies of the considered type of molecular fragmentation.
Testosterone inhibits matrix metalloproteinase-1 production in human endometrial stromal cells in vitro
Authors: Ishikawa Tomonori , Harada Tatsuya , Kubota Toshiro , Aso Takeshi
Published: July 2007

Androgen receptor (AR) is reported to be expressed in human uterine endometrium, but not much information is available on the role of androgens in human endometrium. The purpose of this study is to investigate the role of androgens in the regulation of matrix metalloproteinase (MMP)-1, which is one of the important MMPs for menstruation and embryo implantation in human endometrium. Human endometrial stromal cells (HESCs) were obtained from human endometrium by enzymatic dissociation method. Purified HESCs were incubated with 17β-estradiol (E2), testosterone, or E2 + testosterone. Progestins (natural progesterone or medroxyprogesterone acetate) or vehicle (dimethyl sulfoxide) were also added to the media instead of testosterone. Furthermore, hydroxyflutamide (FLU),a specific AR antagonist, was also supplemented to cultured media. The amounts of MMP-1 in cultured media and in HESC lysates were examined by ELISA measurements and western blotting analysis respectively. The expression of ARmRNA in HESCs RNA was analyzed by RT-PCR. Testosterone significantly inhibited MMP-1 in both cultured media and cell lysates in a dose-dependent manner. Progestins also inhibited MMP-1. Furthermore, FLU completely recovered the decrease of MMP-1 induced by testosterone. ARmRNA was detected in all HESCs RNA. The present study demonstrated that the secretion and production of MMP-1 in HESCs in vitro were inhibited by testosterone through androgen receptors in a manner similar to that seen for progesterone. These findings indicate that androgen may play an important role in morphological and functional changes of human endometrium.
Business Ethics in Developing Countries: A Response to Rossouw
Authors: Schwartz Michael
Published: July 2007

“Business Ethics in Developing Countries: A Response to Rossouw” examines Gedeon J. Rossouw's account of business morality and those preconditions that he seeks in order to develop a moral business culture in South Africa, given the historical reality in that country. The paper argues that Rossouw does not take cognisance of history. Particularly of the decade after the election of the Nationalist Party Government in 1948, when that government strove to impose its ideology upon South African Society. If he did take cognisance of that history, then he would not be able to proffer those proposals which he believes would improve business morality there. The paper also extends a caution against the acceptance of economic advancement as a pre-condition for the appearance of moral business practices. Likewise for the contrary view that economic growth is the harbinger of moral decay.
Varieties of Postmodernism as Moments in Ethics Action-Learning
Authors: Nielsen Richard P.
Published: July 2007

Through an international case study, this paper illustrates how a conversation method was used effectively to address a cross-cultural ethics problem. The method included as moments in one continuous process three different dimensions of postmodernism—Gadamer reconstruction, Derrida deconstruction, and Rorty neopragmatism. In addition to including different dimensions of postmodernism, the method combines effective mutual learning and effective action. Strengths and limitations of the approach are discussed. The article demonstrates how it can be beneficial to build bridges between and within the postmodernism and organization ethics literatures. Also, the article demonstrates how postmodernism can be positively ethical and not necessarily aethical or nihilistic.
Guiding Principles of Jewish Business Ethics
Authors: Green Ronald M.
Published: July 2007

This discussion develops six of the most important guiding principles of classical Jewish business ethics and illustrates their application to a complex recent case of product liability. These principles are: (1) the legitimacy of business activity and profit; (2) the divine origin and ordination of wealth (and hence the limits and obligations of human ownership); (3) the preeminent position in decision making given to the protection and preservation (sanctity) of human life; (4) the protection of consumers from commercial harm; (5) the avoidance of fraud and misrepresentation in sales transactions; and (6) the moral requirement to go beyond the letter of the law. Although these Talmudic principles are clearly obligatory only for “Torah-obedient” Orthodox and Hasidic Jews, many Jews share a sensibility informed by them. Non-Jews, too, may be instructed by Jewish teachings about business ethics.
A Global Perspective of Ethics in Business
Authors: Yamaji Keizo
Published: July 2007

Business ethics should not just be a corporate code, but be implemented in the line of business as a corporate philosophy. As an example of the above, I would like to present corporate activities of Canon, Inc. based on the “Kyosei” Initiative which I directed, especially its global development. I would like to show that these activities are ahead of the times and result in great prosperity of a corporation, and to tell my dream to increase corporations which take the same types of actions based on the “Kyosei” Initiative.
The New Federalism: Implications for the Legitimacy of Corporate Political Activity
Authors: Christensen Sandra L.
Published: July 2007

The new push to move political issue activity from the federal to the state and local levels—a new New Federalism—has implications for the ethical and political legitimacy of business political activity. While business political activity at the federal level may be both less costly and less risky than when action shifts to states or localities, at the state or local level it is likely to be more visible, and individual firms may be perceived to have more power. Increased corporate power raises questions about the legitimacy of firm involvement in the political process at the state and local levels. The issue of legitimacy is viewed in the context of the literature on political subcultures being used to study state economic development.
Rethinking the Responsibility of International Corporations: A Response to Donaldson
Authors: Koehn Daryl
Published: July 2007

In "The language of International Corporate Ethics," Tom Donaldson largues that ethical languages focusing on avoidance of harm to human beings; on rights/duties: and on rules spelled out in a social contract are better for characterizing international corporate responsibility than languages promoting virtue; the mastering of the self; or the maximization of human welfare. While some of what Donaldson says about the strengths and weaknesses of individual theories is quite plausible and relatively noncontroversial, Donaldson does not, in my judgment, establish that the three theories he favors are indeed better equipped to cope with problems of corporate responsibility than the three he dismisses. I will focus upon four major problems with his analysis.
A Comparison of Japanese and U.S. Corporate Financial Accountability and its Impact on the Responsibilities of Corporate Managers
Authors: Hazera Alejandro
Published: July 2007

This paper addresses whether the adoption of Japanese financial practices by U.S. corporations can be used as a basis for encouraging U.S. managers to promote the interests of their (human) organizations over those of stockholders. An historical overview is provided of how the corporate organization in each country evolved and the corresponding development of managers’ responsibilities to the corporate organization versus shareholders. These concepts are then examined within the context of each country’s contemporary corporate financial structure and the corresponding financial responsibilities of managers to the corporate organization versus shareholders. A discussion is then provided of whether the values embodied in each system would affect the ability of the United States to encourage a more “corporate-oriented” ethic in its managers by adopting Japanese financial practices.
One Voice? or Many? A Response to Ellen Klein
Authors: Frederick William C.
Published: July 2007

If one disregards the several petty, and often blatantly unfair, complaints voiced by Dr. Ellen Klein, she raises an issue that is worth considering: Who is qualified to teach business ethics? Her answer is plain and straightforward: only philosophers need apply.
Freeman and Evan: Stakeholder Theory in the Original Position
Authors: Child James W. , Marcoux Alexei M.
Published: July 2007

We argue that the Rawlsian social contract argument advanced for stakeholder theory by R. Edward Freeman, writing alone and with William M. Evan, fails in three main ways. First, it is true to Rawls in neither form, nor purpose, nor the level of knowledge (or ignorance) required to motivate the veil of ignorance. Second, it fails to tailor the veil of ignorance to the fairness conditions that are required to solve the moral problem that Freeman and Evan set out to solve (whereas Rawls’s own use of the device surely tailors the veil of ignorance to the problem of designing a just social order). Third, the argument, considered apart from its claimed Rawlsian pedigree, fails to bolster the stakeholder theory because it fails to demonstrate the rationality of adopting the institutional rules that Freeman and Evan favor.
In Search of Experts: A Conception of Expertise for Business Ethics Consultation
Authors: Wicks Andrew C. , Glezen Paul L.
Published: July 2007

This paper explores the subject of ethics expertise. We suggest that this is a topic which has been badly neglected despite ongoing discussions about subjects which presuppose a particular conception of expertise (e.g., codes of conduct, certification requirements). In addition, given significant challenges to any conception of ethical expertise, we try to determine whether it is possible to provide a meaningful and substantive account of it. The paper moves from more abstract discussion of the idea to grounding a particular model, providing substance to it, and discussing specific traits or qualities of ethics experts.
Epilogue: Whither Method? And Why?
Authors: Frederick William C.
Published: July 2007

For those who, like myself, are enthusiastic advocates of normativelydriven empirical studies of business ethics and values, a display of expert knowledge concerning methods of the sort we see here is occasion for large measures of professional satisfaction. With all of their imperfections and qualifications, all of the tentativeness attached to the truths they yield, these methods (and similar others not included here) open vistas not accessible by other modes of inquiry. For these gains, scholars everywhere should be grateful.

Yet, questions nag at the back of one's mind, even as the positive accomplishments are registered.
The Feminine Firm: A Comment
Authors: Dobson John
Published: July 2007

In this comment I challenge two of the arguments made in the paper, “Toward the Feminine Firm.” First I challenge the claim that Gilligan's work on gender differences in moral orientation provides a logically and empirically sound foundation for an alternative theory of the firm. I cite recent work that discredits any concise notion of a feminine ethic. Second I challenge the claim that, if such a firm were to exist, it would flourish in a competitive market economy. I suggest that, far from flourishing, such a firm will rapidly perish.
Social Products Liability: The Case of the Firearms Manufacturers
Authors: Brenkert George G.
Published: July 2007

One of the most important and challenging issues of business ethics—or indeed of ethics more generally—is that of “moral responsibility.” And though this problem has been with us from the outset of reflection on ethics and business, the following developments in the late twentieth century have exacerbated its difficulty: the increased mobility among people, the development of increasingly complex technologies with ever more significant consequences, the extension of the distance between people’s actions and the effects of their actions, the extended distance between the manufacturers of products and the consequences of those products, the expanded possibilities for anonymous actions, and the collapse of many customary forms of restraints between both individuals and organizations. As a consequence, I believe, we are in the midst of rethinking and developing new and creative ways of extending our notion of responsibility.
The Impact of Legal Age Discrimination on Women in Professional Occupations
Authors: Kurland Nancy B.
Published: July 2007

This paper describes how anticipated age discrimination in the form of disparate treatment induces behavior that in effect constitutes gender discrimination. Potential employers often exhibit a common pattern of behavior that acts to discriminate against older workers entering a specific workplace. Women, at a decision-making point early in their lives, are aware of this pattern of discrimination. They perceive that it is important for them to establish their careers before they have a family because it will be more difficult for them to enter the work force at a later age and excel at their careers. This anticipated age discrimination disparately impacts women, resulting in gender discrimination.
Analysis of Roman Wall Paintings Found in Verona
Authors: Mazzocchin Gian Antonio , Rudello Danilo , Murgia Emanuela
Published: July 2007

The present paper deals with the analysis of roman wall paintings fragments recovered from twelve buildings of Verona, Italy. The analytical techniques used were Optical Microscopy, Scanning Electron Microscopy (SEM) equipped with an EDS microanalysis detector, Xray powder diffraction (XRD) Fourier Transform infrared spectroscopy (FTIR) and Raman Spectroscopy. The wall preparation generally consisted of three layer: the pictorial layer, an intonachino layer of hydrated lime and a plaster one made of slaked lime and sand. The pigments found in the studied domus are different reflecting the taste and culture of Xa Regio of Italy but also the economical possibilities of the dominus and the building period.
Mercury(II) Ion‐Selective Electrodes Based on Heterocyclic Systems
Authors: Mahajan Rakesh Kumar , Sood Pallavi , Mahajan Mohinder Pal , Marwaha Alka
Published: July 2007

Mercury ion‐selective electrodes (ISEs) were prepared with a polymeric membrane based on heterocyclic systems: 2‐methylsulfanyl‐4‐(4‐nitro‐phenyl)‐1‐p‐tolyl‐1H‐imidazole (I) and 2,4‐diphenyl‐1‐p‐tolyl‐1H‐imidazole (II) as the ionophores. Several ISEs were conditioned and tested for the selection of common ions. The electrodes based on these ionophores showed a good potentiometric response for Hg2+ ions over a wide concentration range of 5.0×10‐5‐1.0×10‐1M with near‐Nernstian slopes. Stable potentiometric signals were obtained within a short time period of 20 s. The detection limits, the working pH range of the electrodes were 1.0×10‐5 M and 1.6‐4.4 respectively. The electrodes showed better selectivity for Hg2+ ions over many of the alkali, alkaline‐earth and heavy metal ions. Also sharp end points were obtained when these sensors were used as indicator electrodes for the potentiometric titration of Hg2+ ions with iodide ions.
Die Anfänge der Organischen Photochemie
Authors: Roth Heinz D.
Published: July 2007

Photochemische Reaktionen unter dem Einfluß von Sonnenlicht finden auf dem Planeten Erde sicherlich schon seit Milliarden von Jahren statt. Wie sind nun Wissenschaftler auf die Idee gekommen, daß die Wechselwirkung von Materie mit Licht nicht nur physikalische Phänomene erzeugen kann, sondern manchmal auch die chemische Beschaffenheit der Materie verändert? Sobald die Sonnen wärme als Energiequelle für Destillationen genutzt wurde, war die Entdeckung photochemischer Reaktionen nur noch eine Frage der Zeit. Man kann sich drei Arten von Veränderungen vorstellen, die das Interesse eines Chemikers erweckt haben könnten: Farbänderungen, die Entwicklung von Gasblasen (zum Beispiel von Sauerstoff bei der Photosynthese) und die Ausscheidung eines Photoproduktes, das weniger löslich ist als die Ausgangsverbindung. Kaum vorhersehbar war dagegen die Beobachtung, daß Sonnenlicht Santoninkristalle zerspringen läßt, weil Santonin und sein Photoprodukt unterschiedliche Kristallgitter haben. – Im Laufe des achtzehnten und neunzehnten Jahrhunderts wurde eine Fülle unterschiedlichster photochemischer Reaktionen entdeckt, einige zufällig, andere als Ergebnis sorgfältig geplanter Versuche. Aber erst mit dem Anbruch des zwanzigsten Jahrhunderts war die Zeit schließlich reif für großangelegte, systematische Untersuchungen, die die Photochemie als ein wichtiges Teilgebiet der Chemie etablierten.
Sehr kurze C‐C‐Einfachbindungen und ihre Ursache; die Länge der zentralen Bindung in Bitetrahedryl
Authors: von Ragué Schleyer Paul , Bremer Matthias
Published: July 2007

Ein kleinerer C‐C‐Abstand und zugleich eine niedrigere Rotationsbarriere, das sind laut ab‐initio‐Rechnungen an Ethan die Folgen einer Vergrößerung des H‐C‐C‐Winkels. Daher ist in Verbindungen wie Bicubyl mit „zurückgebogenen”︁ Substituenten an der zentralen C–C‐Bindung diese Bindung viel kürzer als eine normale C‐C‐Einfachbindung. Da die Winkelvergrößerung eine Rehybridisierung mit einem höheren s‐Charakter der C–C‐Bindung bewirkt, kann die Bindung in Bitetrahedryl (berechnete Länge 1.438 Å) bezüglich der Hybridisierung mit der C‐C‐Einfachbindung in Butadiin (1.384 Å) verglichen werden.
Trinacren – das Produkt einer strukturgerechten Synthese
Authors: Ashton Peter R. , Isaacs Neil S. , Kohnke Franz H. , d'Alcontres Guglielmo Stagno , Stoddart J. Fraser
Published: July 2007

Eine vielversprechende – und wunderschöne – neue Hohlraumverbindung ist Trinacren 1, das nach einem alten Namen von Sizilien – Trinacrien – benannt ist. Die Synthese von 1 gelang in zwei Stufen durch sechs Diels‐Alder‐Reaktionen (2×3) hochsymmetrischer Vorstufen, wobei die zweite Stufe eine Hochdruckreaktion (10 kbar) ist. Das D3h‐symmetrische 1 zeigt wie erwartet nur fünf 1H‐NMR‐Signale.

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Hg8‐Cluster („Mercuban”︁) in Rb15Hg16
Authors: Deiseroth Hans‐Jörg , Strunck Axel
Published: July 2007

Isolierte, nahezu würfelförmige Hg8‐Cluster („Mercuban”︁) wurden in dem Rubidiumamalgam Rb15Hg16 erstmals nachgewiesen. Metallisch goldfarbene Einkristalle dieser bisher unbekannten Verbindung bildeten sich bei erfolglosen Versuchen zur Synthese von RbHg. Die Geometrie der Cluster left den Schluß nahe, daß die chemische Bindung zwischen den Hg‐Atomen infolge Elektronenübertragung vom elektropositiven Rubidium wahrscheinlich primär σp‐(6p) und nicht σs‐Charakter hat wie in den schon klassischen Polykationen des Quecksilbers Hg.
Dimerisiert Cyanacetylen beim Erhitzen zu 1,3‐Cyclobutadien‐1,2‐dicarbonitril?
Authors: Witulski Bernhard , Ernst Ludger , Jones Peter G. , Hopf Henning
Published: July 2007

Möglicherweise, lautet die Antwort auf die Titelfrage. Fest steht jedoch, daß beim Erhitzen von Cyanacetylen 1 auf 160°C in Benzol Intermediate entstehen, die sich so verhalten wie Cyclobutadien‐1,2‐dicarbonitril (2a,b). Dies konnte jetzt in Gegenwart von [2.2] Paracyclophan als Abfangreagens gezeigt werden, das die Diels‐Alder‐Addukte von 2a und 2b liefert.

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Biomimetische Synthese eines umgewendeten Porphyrinoids mit peripheren N‐Atomen
Authors: Schumacher Karl‐Heinz , Franck Burchard
Published: July 2007

Stickstoffatome in der Peripherie statt im Innern des Molekülskennzeichnen umgewendete Porphyrinoide, von denen als erstes1biomimetisch aus dem Hydroxymethylpyrrol2in 71% Ausbeute erhalten wurden.

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Peptide als „Schaltelemente”︁: Medium‐induzierte Konformationsübergänge von gezielt entworfenen Peptiden
Authors: Mutter Manfred , Hersperger René
Published: July 2007

Eine plötzliche reversible Umwandlung α‐Helix → β‐Faltblatt beim synthetischen Oligopeptid 1 wurde in Mischungen aus 45% 2,2,2‐Trifluorethanol und 55% H2O beobachtet. Das amphiphile 1 und zwei Isomere wurden extra für diese Untersuchungen konstruiert. Solche in mehreren Konformationen auftretende Peptide könnten als „Schaltelemente”︁ beim de‐novo‐Design künstlicher Proteine Verwendung finden.
Bis(1,4,7‐trithiacyclononan)gold‐Dikation: Ein paramagnetischer, einkerniger AuII‐Komplex
Authors: Blake Alexander J. , Greig John A. , Holder Alan J. , Hyde Timothy I. , Taylor Anne , Schröder Martin
Published: July 2007

Eindeutig einkernig ist der d9‐AuII‐Komplex, der bei der Umsetzung von KAuCl4 mit zwei Äquivalenten 1,4,7‐Trithiacyclononan ([9]anS3) in siedendem wäßrigem HBF4/MeOH entsteht (Struktur von [Au([9]‐anS3)2]2⊕ 1 siehe rechts). Das ESR‐Spektrum zeigt ein starkes Signal bei g = 2.010 (T = 77 K) mit deutlicher Hyperfeinkopplung. Eine Delokalisierung der positiven Ladung von 1 über die Liganden spielt wahrscheinlich nur eine untergeordnete Rolle.

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Cyclophane als Katalysatoren: Ein Porphyrin‐überbrücktes Cyclophan als Modell für Cytochrom‐P‐450‐Enzyme
Authors: Benson David R. , Valentekovich Robert , Diederich François
Published: July 2007

Zur Nachahmung der Monooxygenase‐Aktivität der Cytochrom‐P‐450‐Enzyme und zur supramolekularen Katalyse der Hydroxylierung polycyclischer Arene wurde das Porphyrin‐überbrückte Cyclophan 1 hergestellt. In Methanol kommt es in der unpolaren Hohlraum‐Bindungsstelle von 1 zur festen Einschlußkomplexierung von Arenen wie Anthracen, Acenaphthylen und Phenanthren. In 2,2,2‐Trifluorethanol in Gegenwart von Iodosobenzol katalysiert das Eisen(III)‐Derivat 2 die Oxidation von Acenaphthylen zu Acenaphthen‐1‐on (65% Ausbeute).

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Te, ein neues Tellur‐Polykation
Authors: Beck Johannes
Published: July 2007

Durch die Oxidation von Tellur mit WCl6 entsteht Te8[WCl6]2. Das bicyclische Te2˙8‐Kation ist im Kristall zu Ketten assoziiert (siehe 1) und kann als Tellurpolykation [Ten]n/4⊕ aufgefaßt werden. Solche Polykationen sind schon vor nahezu 20 Jahren von R. J. Gillespie postuliert worden, konnten aber bis heute nicht strukturell charakterisiert werden.

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[nBuLi·LiOtBu]4, Struktur eines n‐Butyllithium‐Lithium‐tert‐butoxid‐Komplexes im Kristall
Authors: Marsch Michael , Harms Klaus , Lochmann Lubomir , Boche Gernot
Published: July 2007

Auffallend kurze Li‐β‐C(Bu)‐ und Li‐β‐H‐Abstände (ca. 235 bzw. 205 pm) charakterisieren das Tetramer [nBuLi · LiOtBu]4 im Kristall. Die eine Hälfte der Li‐Atome ist dreifach koordiniert (an zwei O‐Atome und ein α‐C‐Atom), die andere vierfach (an ein O‐Atom, zwei α‐C‐Atome und ein β‐C‐Atom). Anhand der Struktur dieses Tetramers kann man vorsichtig über die Struktur der komplexen Superbasen („Lochmann‐Basen”︁) [RLi · MOR′] (M = Na, K, Rb, Cs) spekulieren.
Stereo‐ und Regioselektivität von chiralen, alkylsubstituierten ansa‐Zirconocen‐Katalysatoren bei der Methylalumoxan‐aktivierten Propen‐Polymerisation
Authors: Röll Werner , Brintzinger Hans‐Herbert , Rieger Bernhard , Zolk Ralf
Published: July 2007

Bis 94% Anteil an isotaktischen Pentaden wird bei der Polymerisation von Propen mit den ansa‐Zirconocen‐Katalysatoren 1 erreicht. Es zeigt sich, daß sperrige β‐Substituenten für die Stereo‐ und α‐Substituenten für die Regioselektivität entscheidend sind. α‐Substituenten begünstigen darüber hinaus den Aufbau langer Ketten (MW bis 9190). R1 = tBu, iPr; R2 = H, Me; μ‐X = Me2C‐CMe2, Me2Si.

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Imidazo[1,2‐e][1,3,5]triazepin‐Derivate: erste Verbindungen mit einem neuen Heterocyclensystem
Authors: Kaupp Gerd , Sailer Klaus
Published: July 2007

Im Eintopfverfahren sind die neuartigen Tetraazaheterocyclen 2 erhältlich, wenn man das Benzimidazolderivat 1 mit RNH2 in wasserfreiem Dichlormethan umsetzt (Raumtemperatur, Ausbeute ca. 60%). Die Verbindungen 2 sind potentielle Vorstufen für Tetraaza‐azulen‐Kationen und lassen wegen ihrer Verwandtschaft zu Pteridinen interessante biologische Wirkungen erwarten (R  H, Alkyl, Aryl).

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Synthese eines β‐Mannosyl‐Chitobiosyl‐Asparagin‐Konjugates—eines zentralen Elements der Core‐Region von N‐Glycoproteinen
Authors: Günther Wolfgang , Kunz Horst
Published: July 2007

Die korrekte β‐glycosidische Verknüpfung zwischen Mannose‐ und Chitobiosyl‐Asparagin‐Einheit in N‐Glycoproteinen gelang synthetisch erstmals beim Aufbau von 1. Entscheidend ist die intramolekulare nucleophile Substitution in 2; das Produkt dieser Reaktion wurde über ein Trisaccharid und ein Trisaccharidisothiocyanat in das Asparagin‐Derivat 1 umgewandelt.

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Abhängigkeit des magnetischen Superaustausches vom Cr…︁ Cr‐Abstand in zweikernigen Chrom(III)‐Komplexen
Authors: Bossek Ursula , Wieghardt Karl , Nuber Bernhard , Weiss Johannes
Published: July 2007

Die Spins ungepaarter Elektronen in zweikernigen CrIII‐Komplexen mit dem Strukturelement A sind antiferromagnetisch gekoppelt. Durch Messung der temperaturabhängigen Suszeptibilitäten wurde nachgewiesen, daß der Betrag dieser Kopplung umgekehrt proportional zur zwölften Potenz des intramolekularen Abstands zwischen den Cr‐Ionen ist (|J|∼r−12).

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Falsche Annahmen über die Zusammenhänge zwischen der Umweltverschmutzung und der Entstehung von Krebs
Authors: Ames Bruce N. , Gold Lois Swirsky
Published: July 2007

In der Öffentlichkeit gibt es zahlreiche falsche Vorstellungen über die Zusammenhänge zwischen Umweltverschmutzung und Krebs beim Menschen. Grundlage dafür ist die irrige Auffassung, daß von der Natur nur Gutes ausgehe. In diesem Beitrag werden acht Fehleinschätzungen herausgegriffen und wissenschaftlichen Erkenntnissen gegenübergestellt.
Mathematische Modellierung chemischer Reaktoren — Entwicklung und Einbindung neuer Technologien
Authors: Matros Yuri Shaevich
Published: July 2007

Die mathematische Modellierung der Prozesse in einem chemischen Reaktor ist ein wichtiges Werkzeug für die schnelle und zuverlässige Entwicklung und Auslegung solcher Reaktoren. Die Modelle beruhen auf grundlegenden Studien des Reaktionsmechanismus und der Kinetik, den Transportvorgängen und den Wechselwirkungen im System. Das eingehende Verständnis der elementaren Vorgänge bringt leistungsfähige und komplexe Modelle für die Simulation dynamischer und stationärer Reaktionsführungen hervor. Mit Hilfe experimentell bestimmter Parameter können neue Verfahren entwickelt und bestehende verbessert werden. Gute Ergebnisse, die unter idealisierten Laborbedingungen erhalten wurden, lassen sich allerdings selten vollständig in die großtechnische Praxis umsetzen. Dies liegt an Faktoren wie Übergangswiderständen, lokalen Gradienten, schwankenden Bedingungen, konstruktiven oder anderen Einschränkungen, die zu ungünstigeren Parameterwerten und höheren Kosten für die Kompensation dieser Unzulänglichkeiten führen. In diesem Beitrag werden auch einige Empfehlungen für Versuche gegeben, diese Unzulänglichkeiten zu beseitigen.
Hochleistungsmaterialien: Trends und Möglichkeiten am Beispiel flüssigkristalliner Polymere
Authors: Economy James
Published: July 2007

In den letzten zehn Jahren haben sich Forschung und Entwicklung vermehrt dem Gebiet der speziellen Polymere zugewendet. Das Interesse bezieht sich auf zwei Kategorien von Polymeren: a) auf Polymere, die in sehr kleinen Mengen als Zusatzstoffe dienen, um kritische Anforderungen als Teil eines Systems erfüllen zu können, und b) auf technische Kunststoffe mit einem hohen Leistungsprofil hinsichtlich des mechanischen Verhaltens und der thermischen Belastbarkeit. Die erste Kategorie reicht von Polymeren für leistungsfähige Resiste und Isolier‐schichten für mikroelektronische Schaltungen bis zu Membranen für Filtrationssysteme. Die zweite Kategorie umfaßt verbesserte Matrixharzsysteme für Hochleistungsverbundwerkstoffe sowie flüssigkristalline Polymere. Dieser Bericht gibt zunächst einen Überblick über Chancen für den Einsatz von Hochleistungsmaterialien und besonders für Spezialpolymere. Anschließend wird der Entwicklungsstand der flüssigkristallinen Copolyester diskutiert, wobei insbesondere auf die Interpretation ihrer Mikrostruktur eingegangen werden soll, ein Hauptproblem bei derartigen Materialien.
Entwicklungsperspektiven für hochtemperaturbeständige Polymere
Authors: Hergenrother Paul M.
Published: July 2007

Mit der Forschung auf dem Gebiet der hochtemperaturbeständigen Polymere wurde in den späten fünfziger Jahren begonnen, vorwiegend zur Erfüllung der Anforderungen in der Luft‐fahrt‐ und Elektronikindustrie. Seither wurde eine große Zahl hochtemperaturbeständiger Polymersysteme beschrieben, von denen mehrere jetzt kommerziell verfügbar sind. Diese Polymermaterialien werden in vielen Anwendungsgebieten eingesetzt, z. B. in der Mikroelektronik, zur Herstellung von Beschichtungen für Kochtöpfe oder Pfannen, von Bindemitteln für Bremssysteme, von Dichtungsmitteln für Brennstofftanks von Hochgeschwindigkeitsflugzeugen, von Zahnrädern in Kopiermaschinen, von Strukturkomponenten für Hochgeschwindigkeitsflugzeuge und Raumfahrzeuge sowie von Folien und Drahtumhüllungen als elektrische Isolierung. Der Weltverbrauch für hochtemperaturbeständige Polymere wurde 1988 auf 90 Mio. kg mit einem Wert von 2.3 Mrd. $ geschätzt. Der Markt wird sich voraussichtlich bis zum Ende des Jahrzehnts verdoppeln. Im Vordergrund des Beitrags stehen Polyimide und Poly(arylether).