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We report a gift exchange experiment. Firms make wage offers; workers respond by determining an effort level. Higher effort is more costly to workers, and firms have no mechanism for punishing or rewarding workers. Consistent with the gift exchange hypothesis, workers provide more effort at higher wages, but undergraduates provide substantially less effort than MBAs. Evidence suggests this results from differences in prior work experience. Firms' nonbinding effort requests are at least partially honored, resulting in increased overall effort for undergraduates. Although higher wages are relatively more costly for lower productivity firms, workers do not provide them with more effort.

This study reports the results of three experiments that examine how preferences for wealth and honesty affect managerial reporting. We find that subjects often sacrifice wealth to make honest or partially honest reports, and they generally do not lie more as the payoff to lying increases. We also find less honesty under a contract that provides a smaller share of the total surplus to the manager than under one that provides a larger share, suggesting that the extent of honesty may depend on how the surplus is divided between the manager and the firm. The optimal agency contract yields more firm profit than a contract that relies exclusively on honest reporting. However, a modified version of the optimal agency contract, which makes use of subjects' preferences for honest reporting, yields the highest firm profit. These results suggest that firms may be able to design more profitable employment contracts than those identified by conventional economic analysis.

The existence of base rate fallacy (BRF) bias is explored employing: (i) a context treatment with a narrative story applied to asset markets and (ii) an isomorphic abstract setting using balls-and-bingo cages. Probability estimates reflect a BRF bias in both treatments, but is stronger with context. Prices track highest expected dividend values (HEDVs) with context, resulting in strongly biased prices relative to the Bayesian norm when biased traders have HEDVs. In the abstract treatment prices do not track HEDVs nearly as closely, resulting in prices closer to the BRF bias only when most traders hold biased beliefs.

This study examines whether personally performing other audit tasks can bias supervising seniors' going-concern judgments. During an audit, the senior performs some audit tasks him/herself and delegates other tasks to staff members. When personally performing an audit task, the senior would focus on the evidence related to that task. We predict that such evidence will have greater influence on the senior's subsequent going-concern judgment. The results of our experiment are consistent with our predictions. When provided with an identical set of information, seniors who performed another audit task for which the underlying facts of the case reflected positively (negatively) on the company's viability, subsequently made going-concern judgments that were relatively more positive (negative). Our results also demonstrate that the well-documented tendency of auditors to attend more to negative information does not always dominate auditors' information processing. Subjects who performed the task for which the underlying facts reflected positively on the company's viability directed their attention to such positive information and, consequently, both their memory and judgments were more positive than those of subjects in the other conditions. Recent findings indicating that biases in seniors' going-concern judgments may not be fully offset in the review process are discussed along with other potential implications of our results.

A new numerical technique for the simulation of gas dynamic discontinuities in compressible flows is presented. The scheme's complexity and structure is intermediate between a higher-order shock-capturing technique and a front-tracking algorithm. It resembles a tracking scheme in that the front geometry is explicitly computed using a level set method. However, we employ the geometrical information gained in an unusual fashion. Instead of letting it define irregular part-cells wherever the front intersects a grid cell of the underlying mesh and separately balancing fluxes for these part-cells, we use the information for an accurate reconstruction of the discontinous solution in these mixed cells. The reconstructed states and again the front geometry are then used to define accurate effective numerical fluxes across those regular grid cell interfaces that are intersected by the front during the time step considered. Hence, the scheme resembles a capturing scheme in that only cell averages of conserved quantities for full cells of the underlying grid are computed. A side-effect is that the small subcell CFL problem of other conservative tracking schemes is eliminated. A disadvantage for certain applications is that the scheme is conservative with respect to the underlying grid, but that it is not separately conservative with respect to the pre- and post-front regions. If this is a crucial requirement, additional measures have to be taken.

Aryl- and heteroaryl carbamates (e.g. Carbaryl and Pirimicarb) are known as plant protection agents. Because many pests develop resistances, new carbamate structures are of interest in plant protection research. Our synthetic approach started with the preparation of heterocyclic enoles such as pyrones 3, quinolones 6, and coumarins, quinolines, and pyridones of the general structure 12. They were obtained from 1,3-dinucleophiles such as anilines 1 and 10, phenols 10, and azomethines 10 by cyclocondensation with malonates. The pyrones 3 reacts with dialkylcarbamoylchlorides 4 in the presence of a base to carbamates 5. Degradation of 3 gave 4-hydroxyquinolones 6 which reacted with 4 to carbamates 9. Methylisocyanate 7 led to carbamates 8. Anilines 10 (X = NH, R3-R3 = -CH=CH-CH=CH-) cyclize with 2-substituted malonates 11 to quinolones 12. Similarly, phenols 10 (X = O, R3-R3 = -CH=CH-CH=CH-) react to coumarins 12. Azomethins 10 (X = N-alkyl, N-aryl, R4 either alkyl, aryl or 6- or 7-membered rings) give with reactive malonates pyridones, tetrahydroquinolines or cycloheptapyridones 12. Monocyclic pyridones 12 were also accessible from dehydracetic acid, followed by oxygen exchange with amines. The reaction of dialkylcarbamoylchlorides 4 with enols 12 in the presence of bases formed carbamates 13. With methylisocyanate 7, carbamates 14 were obtained. The evaluation of the biological activity shows, that 2 representatives from structures 6 and 12 exhibit strong plant protection properties.

Energetics such as RDX, HMX, and CL-20 exhibit low sorption and natural degradation, resulting in widespread groundwater contamination. Alternatively, TNT exhibits strong sorption and degrades to toxic recalcitrant intermediates. Field scale abiotic, biotic, and coupled abiotic/bioremediation can be more cost effective than pump and treat or sediment removal, but rates of processes in relevant insitu conditions need to be understood.

Players bargained over chips with different exchange rates and with different information regarding these exchange rates. Offers generally reflected a self-serving definition of fairness. There is ample evidence that relative income shares entered players utility functions, resulting in predictable variations in both rejection rates and offers. However, offers were significantly more likely to be rejected when first-movers intentionally offered unequal money splits compared to when comparable offers were clearly unintentional. When both players were fully informed and first-movers had higher exchange rates, conflicting fairness norms developed, resulting in unusually high rejection rates. Journal of Economic Literature Classification Numbers: C72, C78, C92.

Previous work on hypothesis generation demonstrates that auditors tend to generate frequently occurring financial statement errors as their initial hypotheses to explain unexpected fluctuations. However, such work does not examine how the initially generated hypothesis affects subsequent performance at identifying an actual error. We hypothesized that the initially generated hypothesis would interfere with an auditor's ability to subsequently switch to a different hypothesis. Thus, if the initial hypothesis were incorrect, auditors would find it difficult to switch hypotheses in order to identify an actual error. Moreover, initially generating a frequent error would exacerbate this difficulty. Auditor-subjects were asked to generate an initial error hypothesis after seeing a pattern of fluctuations in which sales and accounts receivable were overstated. After they generated their initial hypothesis, half of the subjects were provided with additional information that was consistent with a very frequent error (sales cutoff) and the other half were provided with information consistent with an infrequent error (sales recorded twice). As expected, we found that initially generating the very frequent error (i.e., sales cutoff) versus some other less frequent error affected auditors' subsequent performance at identifying actual errors. Specifically, auditors who generated the very frequent error as their initial hypothesis performed best when it was the actual error, but performed worst when the infrequent error was the actual error. In contrast, auditors who generated a less frequent error as their initial hypothesis performed moderately well (i.e., between best and worst) both when the actual error was frequent and when it was infrequent. The implications of these results for audit efficiency and effectiveness are discussed.

Resume. Les travaux anterieurs qui ont porte sur la formulation d'hypotheses demontrent que les verificateurs ont tendance, dans la formulation de leurs hypotheses initiales, a attribuer les fluctuations imprevues aux erreurs qui se produisent frequemment dans les etats financiers. L'on ne s'interroge cependant pas, dans ces travaux, sur la nature de l'incidence des hypotheses initiales sur la performance subsequente dans le diagnostic de l'erreur veritable. Les auteurs avancent que l'hypothese formulee au depart et la capacite des verificateurs de passer par la suite a une hypothese differente interferent. Si, par exemple, l'hypothese initiale etait inexacte, il serait difficile pour les verificateurs de changer d'hypothese dans le diagnostic de l'erreur veritable. Plus encore, le fait d'invoquer initialement une erreur frequente exacerberait cette difficulte. L'on a demande aux verificateurs-sujets de produire une hypothese initiale relative a l'erreur apres avoir pris connaissance d'un modele de fluctuations dans lequel les ventes et les comptes clients etaient surevalues. Une fois formulee leur hypothese initiale, la moitie des sujets recevaient de l'information supplementaire revelant l'existence d'une erreur tres frequente (dans la demarcation des ventes) et l'autre moitie recevaient de l'information revelant l'existence d'une erreur peu frequente (celle de la double comptabilisation d'une meme vente). Conformement a leurs previsions, les auteurs constatent que le fait, pour les verificateurs, d'invoquer initialement l'erreur tres frequente (soit la demarcation des ventes) par rapport a une autre erreur moins frequente avait par la suite une incidence sur leur performance dans le diagnostic des erreurs veritables. Plus precisement, les verificateurs qui invoquaient l'erreur tres frequente dans leur hypothese initiale obtenaient les meilleurs resultats lorsque cette erreur etait l'erreur veritable, mais ils obtenaient les resultats les moins bons lorsque l'erreur peu frequente se trouvait etre l'erreur veritable. Les verificateurs qui invoquaient une erreur moins frequente dans leur hypothese initiale affichaient, pour leur part, une performance relativement bonne (c'est-a-dire se situant entre la performance la meilleure et la performance la moins bonne), aussi bien lorsque l'erreur veritable etait frequente que lorsqu'elle etait peu frequente. Les auteurs analysent les consequences de ces resultats sur l'efficience et l'efficacite de la verification.

We provide a list of Points to Consider (PTCs) to help researchers self-assess whether they have addressed certain common issues that arise frequently in accounting research seminars and in reviewers’ and editors’ comments on papers submitted to journals. Anticipating and addressing such issues can help accounting researchers, especially doctoral students and junior faculty members, convert an initial empirical accounting research idea into a thoughtful and carefully designed study. Doing this also allows outside readers to provide more beneficial feedback rather than commenting on the common issues that could have been dealt with in advance. The list, provided in the Appendix, consists of five sections: Research Question; Theory; Contribution; Research Design and Analysis; and Interpretation of Results and Conclusions. In each section, we include critical items that readers, journal referees, and seminar participants are likely to raise and offer suggestions for how to address them. The text elaborates on some of the more challenging items, such as how to increase a study’s contribution, and provides examples of how such issues have been effectively addressed in previous accounting studies.

Most large companies voluntarily disclose information about their corporate social responsibility (CSR) activities. We use experimental markets to examine how managers’ disclosures of a particular type of CSR, green investment, affect investors’ bidding behavior. We find that, although in our setting such investments have no impact on future cash flows, investors value knowing that a green investment was made and also respond more favorably to disclosures that focus on the societal benefits of the investment versus on the cost to the company. Managers appear to anticipate investors’ positive reaction, overwhelmingly disclosing when they made a green investment and more often focusing their disclosures on the societal benefits rather than on the cost to the company. Although managers and other current shareholders benefit when managers disclose their green investment, the benefit is always lower than the cost of the investment, and thus both the manager and other current shareholder always bear a cost when the manager makes a green investment. This suggests that many managers in our study make green investments because they value the associated societal benefits. Collectively, our results show that both investors and managers trade off personal wealth for societal benefits associated with CSR activities and help explain why voluntary CSR disclosures often focus on the benefits to society rather than on the cost to the company. Our study also demonstrates how experiments can effectively study important CSR issues that are difficult to address using archival data.

Firms have increasingly adopted open work environments. Although openness is thought to have benefits, it could also expose firms to an unanticipated cost. An open (closed) internal reporting environment makes it more (less) likely that managers will observe a colleague’s communications with senior executives. This increase in what one manager knows about another manager’s communication to senior executives could facilitate employee collusion to extract resources from the firm. To test whether internal reporting openness results in more collusion, we conduct an experiment in which two managers each make separate reports to the firm about cost information they know in common but that is unknown by the firm. Because both managers face the same truth-inducing contract, conventional economic theory predicts that they will not collude to misreport costs regardless of reporting openness. However, using behavioral theory involving trust and reciprocity, we predict and find that managers honor their non-binding collusive agreements and successfully collude more often in an open versus closed internal reporting environment, leading to lower firm welfare in the open environment. These results suggest that firms should consider how the cost of collusion compares to the benefits of openness.

Intuition dictates that figurative language and especially metaphorical expressions should convey sentiment. It is the aim of this work to validate this intuition by showing that figurative language (metaphors) appearing in a sentence drive the polarity of that sentence. Towards this target, the current article proposes an approach for sentiment analysis of sentences where figurative language plays a dominant role. This approach applies Word Sense Disambiguation aiming to assign polarity to word senses rather than tokens. Sentence polarity is determined using the individual polarities for metaphorical senses as well as other contextual information. Experimental evaluation shows that the proposed method achieves high scores in comparison with other state-of-the-art approaches tested on the same corpora. Finally, experimental results provide supportive evidence that this method is also well suited for corpora consisting of literal and figurative language sentences. © 2012 ACM.

Experimental markets were used to examine whether individual probability judgment biases affect market prices. This issue is important to accounts because users of accounting information (especially investors) face competitive market environments. The expectation was that it would be more difficult for prices to be unbiased in markets where biased traders had the highest expected payoffs than in markets where unbiased traders had the highest expected payoffs. This expectation arose from the observation that competitive forces would produce biased prices when biased traders had the highest expected payoffs unless either (1) biased traders learned to be unbiased as a result of market experience, or (2) biased traders were inactive, thus allowing unbiased traders to set prices. Consistent with expectations, prices were biased in a market where biased traders had the highest expected payoffs. That is, individual judgement biases persisted, biased traders remained active, and prices were biased accordingly. Results were less clear in a market where unbiased traders had the highest expected payoffs, with prices moving toward unbiased prices but remaining more biased than unbiased overall. The results of this study suggest that individual judgment biases can have a substantial effect on market prices, and, consequently, demonstrations of individual investor judgment biases should be of concern to accountants.

When providing users with data, accountants often must choose the proper level of aggregation. Research in accounting has shown that the level of aggregation can effect the behavior of decision makers. For example, decision maker's choices between alternatives, each of which involves the occurence of two independent events, often are made on the basis of the probabilities associated with the separate events rather than a comparison of the joint probabilities as prescribed by normative theory. Most evidence from prior studies in consistent with the sequence effect hypothesis, which suggests that people prefer the alternative with the higher probability of success for the first of the two events. This study provides the first evidence that people often use a different strategy which we call the “similarity strategy” to choose between two alternatives. This strategy involves choosing the alternative for which the event probabilities are more similar (i.e. the alternative for which the difference between the probability of success for the two independent events is small relative to the other alternative). The similarity strategy applies to a much broader set of managerial accounting and investment decision settings than the choice strategies identified in previous studies. Thus, an important contribution of this study is that it expands considerably the potential scope of accounting research in the area.

Management of the painful neuroma has been subject to controversy since the earliest descriptions of this disabling problem. Today, treatment is limited to resection of the neuroma and implantation of the nerve in a muscle at a location where it is safe from irritation and trauma. This however is not attainable in many cases and it is our clinical experience, that nerves without a target remain a source of constant discomfort and pain. Recently we reported of the feasibility of neuroma prevention through end-to-side neurorraphy into adjacent sensory and/or motor nerves to provide a target for axons deprived of their endorgan. Here we report of our first clinical experience with this method in sixteen patients with longstanding upper and lower extremity neuromas.16 patients were included in this study. All had neuromas of different sensory nerves of both the upper and lower extremity. 11 were of iatrogenic origin, 5 were caused by different traumas. 8 had previous attempts to surgically treat the neuroma. Finally, all were treated by end-to-side neurorraphy into adjacent nerves. Postoperatively quantitative sensorymotor testing was performed to evaluate possible changes of nerve function of the recipient nerves. Pain was evaluated by visual analogue score and changes in pain medication.In no patient a sensory or motor deficit or painful sensations were induced in the target area of the recipient nerve. Some had dysaesthesias for about 6 months, which finally subsided. All but 1 patient improved in their symptoms at a follow-up of more than 2 years.Previous experimental work and present clinical results suggest that axons of a severed peripheral nerve that are provided with a pathway and target through an end-to-side coaptation will either be pruned or establish some type of end-organ contact so that a neuroma can be prevented without inducing sensory or motor dysfunctions in the recipient nerve.

High-voltage burns represent a challenging surgical entity. Compared to conventional burns, these injuries are characterized by an increased morbidity and worse potential for rehabilitation. The aim of the present study was to analyse the management of high-voltage injuries during the early posttraumatic period with special emphasis on the surgical procedures.We retrospectively evaluated the medical records of patients with electrical injuries treated from 1995 - 2007. A total of 61 patients (57 men, 4 females, mean age: 34 +/- 13 years) with high-voltage burns was included for analysis.The majority of high-voltage burns was work-related (75 %). The mean total burn area was 35 % of the total body surface, with a mean of 29 % deep burns. An average of 4.8 +/- 4 operations were performed per patient (range: 1 - 23 operations). Surgical procedures included repeated debridement/necrectomy (100 % of all patients), early escharotomy/fasciotomy (47.5 %), and amputations (18 %). 14 patients (23 %) underwent reconstructive surgery using either local or free flaps. The mortality rate was 15 %.The surgical management of high-voltage burns is characterised by repetitive debridements and necrectomies. Despite an aggressive approach to remove necrotic tissue, the mortality in this type of injury is considerably high. Limb salvage may be achieved with the use of free microvascular flaps. However, an amputation of necrotic extremities must be considered in the copresence of septic complications.

Enhanced influx of blood-derived serum albumin into the brain is seen after blood-brain barrier disrupture and may induce neurodegeneration. The aim of the present study was to explore the effects of high levels of bovine serum albumin (BSA) on the survival of cholinergic neurons in organotypic brain slices of the basal nucleus of Meynert and in comparison in isolated primary astroglia. When brain slices were exposed to high BSA concentrations, a strong tissue shrinkage was observed accompanied with cholinergic cell death. The shrinkage was prevented by endothelial cell growth factor and heparin. In primary astrocytes, high BSA concentrations induced stress fiber formation, which was reduced by hydrocortisone or the phosphoinositol-3-kinase inhibitor LY294002. In conclusion, high BSA levels are neurotoxic for brain neurons. Cholinergic neurons are protected in an intact astroglial network, which might be of importance in neurodegenerative diseases, such as Alzheimer’s disease.

In order to master the growing complexity of analogue electronic systems, modelling and simulation of analogue hardware at various levels is absolutely necessary. This paper presents an original modelling method based on the graphical description of analogue electronic functional blocks. This method is intended to be automated and integrated into a design framework: specialists create behavioural models of existing functional blocks, that can then be used through high-level selection and specification. Applications of behavioural modelling are discussed. >

This study aims to assess the suitability of biodegradable membranes as transfer matrix materials for the culture of subconfluent fibroblasts and keratinocytes. The materials investigated were based on collagen, chitosan and enzyme-digestible cellulose. The proliferation and growth behaviour of human keratinocytes and dermal fibroblasts were analysed and morphology and distribution determined. Cultured fibroblasts exhibited no significant differences in proliferation for the different membrane types, whereas keratinocytes revealed significantly higher proliferation on collagen membranes compared with membranes based on cellulose and chitosan. Co-cultured fibroblasts and keratinocytes from the same donor on collagen membranes showed more homogenous cell distribution, but they segregated in heterologous co-cultures; this effect must be further investigated. Thus, collagen and collagen-coated chitosan membranes are suitable for the subconfluent transfer of human fibroblasts and keratinocytes.

We conducted an experiment in which participants acted as employees under either a bonus contract or an economically equivalent penalty contract. We measured participants’ contract preference, their degree of expected disappointment about having to pay the penalty or not receiving the bonus, their perceived fairness of their contract, and their effort level. Consistent with Luft (1994), we find that employees generally preferred the bonus contract to the penalty contract. We extend Luftŕss work by demonstrating that loss aversion caused employees to expend more effort under the penalty contract than under the economically equivalent bonus contract. That is, employees were more averse to having to pay the penalty than they were to not receiving the bonus, and consequently they chose a higher level of effort under the penalty contract to avoid paying the penalty. However, we also find evidence of reciprocity in that employees who considered their contract to be fairer chose a higher level of effort. Because our participants generally considered the bonus contract fairer than the penalty contract, reciprocity predicts higher effort under the bonus contract, a result opposite to our finding. Our overall result that employee effort was greater under the penalty contract is explained by the fact that, while higher perceived fairness did increase effort, this effect was dominated by the more powerful opposing effect of loss aversion. We discuss the implications of these results for explaining why in practice most actual contracts are bonus contracts rather than penalty contracts.

Nerve growth factor (NGF) is an important factor regulating survival in development and during regenerative or neuroinflammatory processes. The aim of this study was to investigate whether brain capillary endothelial cells (BCEC) respond to NGF and whether pro-inflammatory substances induce the secretion of NGF in these cells. Cells were incubated with the growth factors NGF or vascular endothelial growth factor or endothelial cell growth factor, and proliferation was observed by incorporation of 5-bromo-2'-deoxy-uridine. NGF-secretion was measured by ELISA and expression of the NGF-receptors trkA and p75(NTR) by Western blot. Proliferation of BCEC was enhanced by exogenous NGF (1-100 ng/ml.). BCEC expressed NGF receptors in vivo (P3, P10, P20, adult) and displayed secretion of endogenous NGF ( approximately 20 pg/ml) into the medium. Treatment of BCEC with the proinflammatory cytokine interleukin-1beta+lipopolysaccharide enhanced expression of p75(NTR) and the secretion of NGF ( approximately 35 pg/ml). The effects of NGF were blocked by anti-NGF antibodies (5 microg/ml). In summary, NGF shows proliferative activity in BCEC, and NGF is secreted after inflammation. Therefore, the NGF pathway can modulate BCEC and may influence blood-brain barrier functions.

A protein fragment of P450BM3 (residues 73-84) which participates in palmitoleate binding was subjected to scanning chimeragenesis. Amino acids 73-84, 73-78, 75-80, and 78-82 were replaced with the homologous fragments of the insect terpenoid hydroxylase CYP4C7. The four chimeric proteins, C(73-84), C(73-78), C(75-80), and C(78-82), were expressed, purified, and characterized. All the chimeric proteins contained all the cofactors and catalyzed monooxygenation of palmitate and of the sesquiterpene farnesol. Chimeragenesis altered substrate binding as shown by the changes in the amplitude of the palmitate-induced type I spectral shift. C(78-82) had monooxygenase activities close to those of P450BM3, while the rest of the chimeric proteins had monooxygenase activities that were inhibited relative to that of wild-type P450BM3. The extent of inhibition of the chimeric proteins varied depending on the substrate, and in the case of C(73-84), farnesol and palmitate oxidation was inhibited by 1 and 4 orders of magnitude, respectively. (1)H NMR spectroscopy and GC-MS were used to identify products of farnesol and palmitate oxidation. Wild-type P450BM3 and all chimeric proteins catalyzed oxidation of farnesol with formation of 9-hydroxyfarnesol and farnesol 10,11- and 2,3-epoxides. Three of the four chimeric proteins also formed a new compound, 5-hydroxyfarnesol, which was the major product in the case of C(73-78). In addition to hydroxylation of the C13-C15 atoms, the chimeric enzymes catalyze significant hydroxylation of the C10-C12 atoms of palmitate. In the case of C(78-82), the rates of formation of 11- and 12-hydroxypalmitates increased 7-fold compared to that of wild-type P450BM3 to 106 and 212 min(-)(1), respectively, while the rate of 10-hydroxypalmitate synthesis increased from zero to 106 min(-)(1). Thus, chimeragenesis of the region of residues 73-84 of the substrate binding site shifted the regiospecificity of substrate oxidation toward the center of the farnesol and palmitate molecules.

Most evidence regarding the independence of memory and judgment comes from studies that used memory measures consisting of Ss' recall of raw input data (recall measures). Such evidence provides the primary support for on-line judgment formation. The results of 2 experiments suggest that self-generated memory measures capture the contents of memory at the time of judgement more effectively than recall measures and, accordingly, are more likely to provide evidence that memory and judgment are related. When directly compared, a self-generated measure provided evidence of a memory-judgment relationship and a recall measure did not. Thus, memory-based judgment formation may be more prevalent than the on-line processing literature suggests.

Beiträge zur Lehrerbildung 9 (1991) 2, S. 241-247, Lehrmittel entstehen heute in der Regel im Team. Neben Fachwissenschaftern und Praktikern werden zur Erarbeitung zunehmend Fachdidaktiker beigezogen. Welches ist ihr Beitrag bei der Lehrmittelerarbeitung und -einführung? Wie beeinflusst die Lehrmittelarbeit das Fach- und Fachdidaktikverständnis? Wie sollen Lehrmittel in Grundausbildung und Fortbildung eingeführt werden? Wie qualifiziert sich ein Fachdidaktiker zum Lehrmittel(mit)autor? Diesen Fragen ging ein Gespräch zwischen drei Lehrmittelautoren nach, deren Aussagen wir hier - gekürzt - wiedergeben.

Galactosyltransferase (GalTF), sialyltransferase (SiaTF), fucosyltransferase (FucTF), 5'-nucleotidase (5'Nucl), and ADP-ribosyltransferase (RibTF) were determined in three subcellular fractions of tumor cells and adjacent control tissue from 20 patients with small primary infiltrating ductal adenocarcinomas of the breast. Viable, as pure tumor cell populations as possible were isolated, subfractionated, and their enzyme levels compared to those in the patients' sera. The activities in tumor cells of the three glycosyltransferases were two- to seven-fold higher, whereas 5'-Nucl and RibTF showed reduced activities when compared to adjacent noninvolved tissue. Serum GalTF and SiaTF were slightly elevated in early mammary carcinoma, whereas FucTF, 5'Nucl, and RibTF were decreased in comparison with a control group. The proposed tumor origin of circulating enzymes could not be confirmed. Surprisingly, only for RibTF could a correlation between tumor and serum activity be established; a weak correlation was found for SiaTF. However, no such relationship could be determined for GalTF, FucTF, or 5'Nucl. In conclusion, the enzyme profile of the tumor cell does not, except for RibTF, appear in the serum. Serum enzyme profiles, therefore, do not permit detection of the early stages of breast cancer. A high correlation between RibTF activity and cytosol estrogen and progesterone receptor levels has been determined in tumor cells, possibly indicating slower growing, more differentiated types of breast tumors.

The analytical modeling and simulation of conservative electrostatic, electromagnetic and electrodynamic transducers found in microsystems using a non-linear lumped-parameter approach is presented in this paper. A comparison is made between this approach and the linearized equivalent circuit method All models of transducers are written in HDL-A(TM), a proprietary analogue hardware description language (HDL). System-level simulation is performed in the SPICE simulator using behavioral models of the transducers. Finally, a parameter extraction and HDL model generation tool for devices is presented.

Early disease diagnosis is key for the effective treatment of diseases. It relies on the identification of biomarkers and morphological inspection of organs and tissues. Histopathological analysis of human biopsies is the gold standard to diagnose tissue alterations. However, this approach has low resolution and overlooks 3D structural changes that are consequence of functional alterations. Here, we applied multiphoton imaging, 3D digital reconstructions and computational simulations to generate spatially-resolved geometrical and functional models of human liver tissue at different stages of non-alcoholic fatty liver disease (NAFLD). We identified a set of new morphometric cellular parameters correlated with disease progression. Moreover, we found profound topological defects in the 3D bile canaliculi (BC) network. Personalized biliary fluid dynamic simulations predicted an increased pericentral biliary pressure and zonated cholestasis, consistent with elevated cholestatic biomarkers in patients’ sera. Our spatially-resolved models of human liver tissue can contribute to high-definition medicine by identifying quantitative multi-parametric cellular and tissue signatures to define disease progression and provide new insights into NAFLD pathophysiology.