bluuebunny/crossref_metadata_2025 huggingface dataset:
Negative Predictive Value of Biopsy Margins in Keratinocyte Carcinoma: A Literature Review
Authors: Purnell Joseph Chase , Duncan James Robert , Stratton Michael Slade , Huang Conway , Phillips Carlton Blake
Published: September 2019

BACKGROUND

Pathologists sometimes include commentary on margin involvement in shave biopsy reports of keratinocyte carcinoma (KC). This practice can lead to confusion regarding the need for further treatment. There is limited literature evaluating the reliability of reported histologic margin status in shave biopsies of KC.

OBJECTIVE

To evaluate the negative predictive value (NPV) of reported clear shave biopsy margins in basal and squamous cell carcinomas to determine whether this assessment is a reliable predictor of complete tumor removal.

METHODS

A literature review was performed using the PubMed database. The data were compiled, NPVs were calculated by the tumor subgroup, and a statistical analysis was performed.

RESULTS

Four studies met inclusion criteria. Two hundred twenty-one KCs were identified (n = 221). All specimens had negative-reported histologic margins (39 squamous cell carcinoma [SCC] and 182 BCC). Fifty-five cases initially noted to have negative margins on biopsy were found to have residual tumor on subsequent analysis: 5 SCC and 50 BCC, translating to 12.8% of all SCC (5/39) and 27.5% for BCC (50/182). Negative predictive values were found to be 75.1% for all KCs, 87.2% for SCC, and 72.5% for BCC.

CONCLUSION

Negative histologic margin status on shave biopsy specimens of KC has a poor NPV and is an inadequate predictor for complete tumor removal.
Discussion of “Dynamic Modeling and Projection-Based Reduction Methods for Bladed Disks With Nonlinear Frictional and Intermittent Contact Interfaces” (Mitra, M., Epureanu, B. I., 2018, ASME Appl. Mech. Rev., 71(5), p. 050803)
Authors: Wallaschek Jörg , Willeke Sebastian , Panning-von Scheidt Lars
Published: September 2019

Mitra and Epureanu have written a very good and complete overview on nonlinear vibrations of turbine blades. Nonlinearities due to friction and contact mechanics are the main focus. Questions related to modeling and model reduction are particularly addressed. This paper begins with an investigation of the vibration behavior of cyclic linear structures, in which a variety of considerations about the occurrence of standing and propagating waves play an important role. Subsequently, several methods of model-order reduction are presented, where cyclic sectors of tuned bladed disks are assumed. The classification of the linear vibration modes according to their nodal diameters (NDs) is explained in detail. Large models with a high number of degrees-of-freedom (DOF) occurring in the field of turbomachinery dynamics lead to very high computational cost. In this context, the authors consider model-order reduction with projection-based methods to be of particular interest. They give an overview of modern projection-based methods and compare them with regard to their respective advantages and disadvantages in the context of bladed disks with nonlinear friction and intermittent contact.
An observational study to examine how cumulative impact zones influence alcohol availability from different types of licensed outlets in an inner London Borough
Authors: Sharpe Carolyn A , Poots Alan , Watt Hilary , Williamson Chris , Franklin David , Pinder Richard J
Published: September 2019

Objectives

Cumulative impact zones (CIZs) are a widely implemented local policy intended to restrict alcohol availability in areas proliferated with licensed outlets. Limited previous research has questioned their effectiveness and suggested they may play a more nuanced role in shaping local alcohol environments. This study evaluates the association between CIZ implementation and the number of licence applications made, and the number issued, relative to a control region.

Design

A quantitative observational study.

Setting

The inner London Borough of Southwark, which currently enforces three CIZs.

Population

Licence applications received by Southwark Council’s Licensing Authority between 1 April 2006 and 31 March 2017 (n=1254).

Interventions

CIZ implementation.

Primary outcome measures

Five outlet types were categorised and evaluated: drinking establishments, eateries, takeaways, off sales and other outlets. Primary outcome measures were the number of applications received and the number of licences issued. These were analysed using Poisson regression of counts over time.

Results

Across all CIZs, implementation was associated with greater increases in the number of eateries in CIZ regions (incidence rate ratio (IRR)=1.58, 95% CI: 1.02–2.45, p=0.04) and number of takeaway venues (IRR=3.89, 95% CI: 1.32–11.49, p=0.01), relative to the control area. No discernible association was found for the remaining outlet types. Disaggregating by area indicated a 10-fold relative increase in the number of new eateries in Peckham CIZ (IRR=10.38, 95% CI: 1.39–77.66, p=0.02) and a fourfold relative increase in the number of newly licensed takeaways in Bankside CIZ (IRR=4.38, 95% CI: 1.20–15.91, p=0.03).

Conclusions

CIZs may be useful as policy levers to shape local alcohol environments to support the licensing goals of specific geographical areas and diversify the night-time economy.
Qualitative study exploring patients experiences of being diagnosed and living with primary bone cancer in the UK
Authors: Martins Ana , Whelan Jeremy S , Bennister Lindsey , Fern Lorna A , Gerrand Craig , Onasanya Maria , Storey Lesley , Wells Mary , Windsor Rachael , Woodford Julie , Taylor Rachel M
Published: September 2019

Objective

The aim of this study is to explore the experiences of patients with primary bone cancer.

Design

Qualitative study design using semistructured interviews and focus groups.

Setting

Hospitals across the UK and recruitment through UK sarcoma charities and support groups.

Methods

Semistructured telephone/face-to-face interviews and focus groups with a purposive sample of 26 participants. Data were analysed using Framework Analysis.

Participants

Patients (n=26) with primary bone cancer aged 13–77 years. The majority were male (69%), white (85%); diagnosed within 4 years (54%); and had lower limb sarcoma (65%). Ten participants had undergone an upper/lower limb amputation (39%).

Results

The health-related quality-of-life domains of physical, emotional and social well-being and healthcare professionals’ role were the overarching themes of analysis. The physical domain anchored patient experiences. The intensity and length of treatment, the severity of side-effects, the level of disability after surgery and the uncertainty of their prognosis had an impact on patient’s self-image, confidence, mood and identity, and caused disruption to various aspects of the patients’ social life, including their relationships (emotional and sexual) and participation in work/school and leisure activities. Adaptation was influenced by the way patients dealt with stress and adversity, with some finding a new outlook in life, and others struggling with finding their ‘new normal’. Family and friends were the main source of support. Healthcare professional’s expertise and support was critical. Rehabilitation services had a considerable role in patient’s physical and emotional well-being, but inequitable access to these services was apparent.

Conclusions

This study described the impact of primary bone cancer on patients’ well-being and adjustment over time with the identification of influencing factors of better/worse experiences. It showed that impact was felt after end of treatment and affected patients at different life stages. Holistic models of survivorship care are needed.
How European primary care practitioners think the timeliness of cancer diagnosis can be improved: a thematic analysis
Authors: Harris Michael , Thulesius Hans , Neves Ana Luísa , Harker Sophie , Koskela Tuomas , Petek Davorina , Hoffman Robert , Brekke Mette , Buczkowski Krzysztof , Buono Nicola , Costiug Emiliana , Dinant Geert-Jan , Foreva Gergana , Jakob Eva , Marzo-Castillejo Mercè , Murchie Peter , Sawicka-Powierza Jolanta , Schneider Antonius , Smyrnakis Emmanouil , Streit Sven , Taylor Gordon , Vedsted Peter , Weltermann Birgitta , Esteva Magdalena
Published: September 2019

Background

National European cancer survival rates vary widely. Prolonged diagnostic intervals are thought to be a key factor in explaining these variations. Primary care practitioners (PCPs) frequently play a crucial role during initial cancer diagnosis; their knowledge could be used to improve the planning of more effective approaches to earlier cancer diagnosis.

Objectives

This study sought the views of PCPs from across Europe on how they thought the timeliness of cancer diagnosis could be improved.

Design

In an online survey, a final open-ended question asked PCPs how they thought the speed of diagnosis of cancer in primary care could be improved. Thematic analysis was used to analyse the data.

Setting

A primary care study, with participating centres in 20 European countries.

Participants

A total of 1352 PCPs answered the final survey question, with a median of 48 per country.

Results

The main themes identified were: patient-related factors, including health education; care provider-related factors, including continuing medical education; improving communication and interprofessional partnership, particularly between primary and secondary care; factors relating to health system organisation and policies, including improving access to healthcare; easier primary care access to diagnostic tests; and use of information technology. Re-allocation of funding to support timely diagnosis was seen as an issue affecting all of these.

Conclusions

To achieve more timely cancer diagnosis, health systems need to facilitate earlier patient presentation through education and better access to care, have well-educated clinicians with good access to investigations and better information technology, and adequate primary care cancer diagnostic pathway funding.
Observational constraints on reheating in braneworld inflation
Authors: Sakhi Z. , Safsafi A. , Ferricha-Alami M. , Chakir H. , Bennai M.
Published: September 2019

The reheating era after inflation is analyzed in the framework of the braneworld models. We study reheating by calculating the reheating temperature in a braneworld inflation for various cosmological parameters. The variation of reheating [Formula: see text]-folding number and reheating temperature were obtained and analyzed as function of a spectrum of perturbation for a polynomial potential [Formula: see text]. We have applied the slow-roll approximation in the high energy limit to constraint the parameter potentials by confronting our results to recent Planck 2018 observations. We have shown that in general the best values of the predicted reheating temperature is of the order [Formula: see text] GeV, with a brane tension [Formula: see text] GeV4. We have also shown that the polynomial potential in the case [Formula: see text] provides the best fit results with recent observational constraints.
Complex Dynamics in a Love-Triangle Model with Single-Frequency and Multiple-Frequency External Forcing
Authors: Deng Wei , Liao Xiaofeng
Published: September 2019

In this paper, a new version of the nonlinear model with two women competing vehemently for an attractive man in a competitive love-triangle is proposed, which provides more insight into the dynamical behaviors of the complex love-triangle relationship. A notable and important feature of this model is that the effects of the competition, single-frequency and multiple-frequency external periodic forcing terms are introduced into the model, as environmental fluctuation on every individual in the love-triangle relationship. By analyzing the dynamical behaviors of the competitive love-triangle model through analytical techniques and numerical simulation, we find that under some simple parametric conditions, with the effects of external periodic forcing, the model gives rise to the appearance of various phenomena such as stability, quasi-limit cycles, and resonant responses. The results show that system parameters and external periodic forcing play a key role in the love-triangle relationship: system parameters can be the control parameters and their different appropriate values can produce different phenomena, while external periodic forcing can enhance or weaken the oscillations of the feeling density, and moreover, the interesting phenomenon called resonant response can occur under some suitable conditions. In this way, complex types of love feelings can be described and it is closer to the reality.
Chaotic Bursting Dynamics and Coexisting Multistable Firing Patterns in 3D Autonomous Morris–Lecar Model and Microcontroller-Based Validations
Authors: Bao Bocheng , Yang Qinfeng , Zhu Lei , Bao Han , Xu Quan , Yu Yajuan , Chen Mo
Published: September 2019

A three-dimensional (3D) autonomous Morris–Lecar (simplified as M–L) neuron model with fast and slow structures was proposed to generate periodic bursting behaviors. However, chaotic bursting dynamics and coexisting multistable firing patterns have been rarely discussed in such a 3D M–L neuron model. For some specified model parameters, MATLAB numerical plots are executed by bifurcation plots, time sequences, phase plane plots, and 0–1 tests, from which diverse forms of chaotic bursting, chaotic tonic-spiking, and periodic bursting behaviors are uncovered in the 3D M–L neuron model. Furthermore, based on the theoretically constructing fold/Hopf bifurcation sets of the fast subsystem, the bifurcation mechanism for the chaotic bursting behaviors is thereby expounded qualitatively. Particularly, through numerically plotting the attraction basins related to the initial states under two sets of specific parameters, coexisting multistable firing patterns are demonstrated in the 3D M–L neuron model also. Finally, a digitally circuit-implemented electronic neuron is generated based on a low-power microcontroller and its experimentally captured results faultlessly validate the numerical plots.
Jacobi Stability Analysis of the Chen System
Authors: Huang Qiujian , Liu Aimin , Liu Yongjian
Published: September 2019

In this paper, the research of the Jacobi stability of the Chen system is performed by using the KCC-theory. By associating a nonlinear connection and a Berwald connection, five geometrical invariants of the Chen system are obtained. The Jacobi stability of the Chen system at equilibrium points and a periodic orbit is investigated in terms of the eigenvalues of the deviation curvature tensor. The obtained results show that the origin is always Jacobi unstable, while the Jacobi stability of the other two nonzero equilibrium points depends on the values of the parameters. And a periodic orbit of the Chen system is proved to be also Jacobi unstable. Furthermore, Jacobi stability regions of the Chen system and the Lorenz system are compared. Finally, the dynamical behavior of the components of the deviation vector near the equilibrium points is also discussed.
Nonlinear Dynamics of Two Discrete-Time Versions of the Continuous-Time Brusselator Model
Authors: Rech Paulo C.
Published: September 2019

In this paper, we report results related with the dynamics of two discrete-time mathematical models, which are obtained from a same continuous-time Brusselator model consisting of two nonlinear first-order ordinary differential equations. Both discrete-time mathematical models are derived by integrating the set of ordinary differential equations, but using different methods. Such results are related, in each case, with parameter-spaces of the two-dimensional map which results from the respective discretization process. The parameter-spaces obtained using both maps are then compared, and we show that the occurrence of organized periodic structures embedded in a quasiperiodic region is verified in only one of the two cases. Bifurcation diagrams, Lyapunov exponents plots, and phase-space portraits are also used, to illustrate different dynamical behaviors in both discrete-time mathematical models.
The Unreasonable Fairness of Maximum Nash Welfare
Authors: Caragiannis Ioannis , Kurokawa David , Moulin Hervé , Procaccia Ariel D. , Shah Nisarg , Wang Junxing
Published: September 2019

The
maximum Nash welfare (MNW)
solution—which selects an allocation that maximizes the product of utilities—is known to provide outstanding fairness guarantees when allocating divisible goods. And while it seems to lose its luster when applied to indivisible goods, we show that, in fact, the MNW solution is strikingly fair even in that setting. In particular, we prove that it selects allocations that are envy-free up to one good—a compelling notion that is quite elusive when coupled with economic efficiency. We also establish that the MNW solution provides a good approximation to another popular (yet possibly infeasible) fairness property, the maximin share guarantee, in theory and—even more so—in practice. While finding the MNW solution is computationally hard, we develop a nontrivial implementation and demonstrate that it scales well on real data. These results establish MNW as a compelling solution for allocating indivisible goods and underlie its deployment on a popular fair-division website.
Alterations in Respiratory Mechanics and Neural Respiratory Drive After Restoration of Spontaneous Circulation in a Porcine Model Subjected to Different Downtimes of Cardiac Arrest
Authors: Yang Zhengfei , Zheng Houzhen , Lin Lin , Hou Jingying , Wen Cai , Wang Yue , Ling Qin , Jiang Longyuan , Tang Wanchun , Chen Rui
Published: September 2019

Background

The potential alterations of respiratory pathophysiology after cardiopulmonary resuscitation (
CPR
) are relatively undefined. While untreated arrest is known to affect post–cardiopulmonary resuscitation circulation, whether it affects respiratory pathophysiology remains unclear. We aimed to investigate the post–cardiopulmonary resuscitation changes in respiratory mechanics and neural respiratory drive with varying delays (5 or 10 minutes) in the treatment of ventricular fibrillation (
VF
).

Methods and Results

Twenty‐six male Yorkshire pigs were used. Anesthetized pigs weighing 38±5 kg were randomized into 3 groups (n=10 each in the
VF
5 and
VF
10 groups, with
VF
kept untreated for 5 and 10 minutes, respectively, and n=6 in the sham group without
VF
). Defibrillation was attempted after 6 minutes of cardiopulmonary resuscitation. Pulse‐induced contour cardiac output, respiratory mechanics, diaphragmatic electromyogram, blood gas, lung imaging, and histopathology were evaluated for 12 hours. Significantly elevated mean root mean square of diaphragmatic electromyogram, transdiaphragmatic pressure, and minute ventilation were observed, but reduced minute ventilation/mean root mean square, dynamic pulmonary compliance, and Pa
o
2
were noted in both
VF
groups. Despite recovery of spontaneous breathing, the abnormalities in respiratory mechanics and neural respiratory drive, Pa
o
2
, and extravascular lung water continued to last for >12 hours. The changes in imaging (
P
=0.027) and histopathology (
P
=0.012) were more severe in the
VF
10 group compared with the VF5 group.

Conclusions

There is an uncoupling between the respiratory center and ventilation after restoration of spontaneous circulation. Prolonged untreated arrest from cardiac arrest contributes to more serious alterations in lung pathophysiology.
CpG Oligodeoxynucleotide Promotes Apoptosis of Human Bladder Cancer T24 Cells Via Inhibition of the Antiapoptotic Factors
Authors: Luo Yang , Dong Yuhang , Liang Shengran , Yuan Lihong , Men Hongsheng , Zhang Shulin , Tian Sujuan , Fu Xiaoyi , Dong Bin , Meng Minjie
Published: September 2019

Objective:

Unmethylated cytosine-phosphorothioate-guanine oligodeoxynucleotide, a synthetic oligodeoxynucleotide, has been used as an adjuvant in clinic and in the antitumor activity. However, the antitumor mechanism of cytosine-phosphorothioate-guanine oligodeoxynucleotide against human bladder cancer is unknown. The purpose of this study is to evaluate the cytotoxicity and molecular mechanism of anticancer effect of cytosine-phosphorothioate-guanine oligodeoxynucleotide on T24 cells (a human bladder cancer cell line).

Methods:

The cytotoxic activity of cytosine-phosphorothioate-guanine oligodeoxynucleotide was examined by cell viability assay in the presence and absence of 5-fluorouracil, respectively. Apoptosis and cell-cycle phase distribution were detected by flow cytometry analysis. To investigate the molecular mechanisms of cytosine-phosphorothioate-guanine oligodeoxynucleotide cytotoxicity, the expression of antiapoptotic factors (B-cell lymphoma-2 and Survivin, β-actin as control) in RNA, and protein level was assayed by quantitative real-time polymerase chain reaction and automated capillary Western blot.

Results:

The inhibition ratio of T24 cells treated with both cytosine-phosphorothioate-guanine oligodeoxynucleotide and 5-fluorouracil was higher than those treated with either cytosine-phosphorothioate-guanine oligodeoxynucleotide or 5-fluorouracil alone. In the combination group (cytosine-phosphorothioate-guanine oligodeoxynucleotide and 5-fluorouracil), the apoptosis rate was significantly increased, and more cells were arrested at “S” and “G2/M” phases compared to those in cytosine-phosphorothioate-guanine oligodeoxynucleotide or 5-fluorouracil alone. Furthermore, the expression of antiapoptotic factors was decreased by cytosine-phosphorothioate-guanine oligodeoxynucleotide alone or combined with 5-fluorouracil.

Conclusion:

Cytosine-phosphorothioate-guanine oligodeoxynucleotide promoted apoptosis and enhanced the chemosensitivity of 5-fluorouracil in T24 cells. Cytosine-phosphorothioate-guanine oligodeoxynucleotide downregulated the expression of antiapoptotic factors and inhibited cell-cycle phase by arresting more cells at “S” and “G2/M” phases. This study indicated the potential ability of cytosine-phosphorothioate-guanine oligodeoxynucleotide as a candidate drug for human bladder cancer.
A survey exploring biomedical editors’ perceptions of editorial interventions to improve adherence to reporting guidelines
Authors: Blanco David , Hren Darko , Kirkham Jamie J. , Cobo Erik , Schroter Sara
Published: September 2019

Background: Improving the completeness of reporting of biomedical research is essential for improving its usability. For this reason, hundreds of reporting guidelines have been created in the last few decades but adherence to these remains suboptimal. This survey aims to inform future evaluations of interventions to improve adherence to reporting guidelines. In particular, it gathers editors’ perceptions of a range of interventions at various stages in the editorial process.  

Methods: We surveyed biomedical journal editors that were knowledgeable about this topic. The questionnaire included open and closed questions that explored (i) the current practice of their journals, (ii) their perceptions of the ease of implementation and the potential effectiveness of different interventions, (iii) the barriers and facilitators associated with these interventions, and (iv) suggestions for future interventions and incentives.

Results: Of the 99 editors invited, 24 (24%) completed the survey. Involving trained editors or administrative staff was deemed the potentially most effective intervention but, at the same time, it was considered moderately difficult to implement due to logistic and resource issues. Participants believed that checking adherence to guidelines goes beyond the role of peer reviewers and could decrease the overall quality of reviews. Journals incentivising adherence, and publishers and medical institutions encouraging journals to adopt strategies to boost adherence were two recurrent themes.

Conclusions: Further evaluation of interventions are required. These evaluations could take into account the points raised in this survey.
Projeto “Andanças Culturais”
Authors: Silva Lucas Emmanuel Nascimento , Gomes Neto Manoel Bastos , Grangeiro Rebeca da Rocha
Published: September 2019

Este relato tem como objetivo apresentar as experiências vivenciadas pelos estudantes e membros da comunidade acadêmica da Universidade Federal do Cariri no Museu Fundação Memorial Padre Cícero e no Geossítio Colina do Horto proporcionadas a partir do projeto “Andanças Culturais”. Este projeto, desenvolvido em parceria entre a Pró-Reitoria de Cultura (PROCULT) da Universidade Federal do Cariri (UFCA) e o Programa de Educação Tutorial do Curso de Administração (PETADM-UFCA), foi criado em 2015 com objetivo de promover um vínculo entre a comunidade acadêmica e a cultura local. O projeto possibilitou aos participantes o reconhecimento da importância histórica, política, econômica e social que o Padre Cícero teve na região do Cariri, sua relevância na esfera religiosa e suas influências no campo da gestão do município de Juazeiro do Norte. A partir da experiência vivenciada, pode-se perceber que os lugares além de serem instrumentos da preservação histórica, são fontes de manutenção da imagem do Padre Cícero como ícone religioso e político da região.
Leveraging Integrated Bike-Sharing with Existing Bus Rapid Transit (BRT) to Reduce Motor Vehicle in Central Jakarta Municipal
Authors: Daniella Daniella , Dharma Wangsa Achmad Amri
Published: September 2019

Jakarta is one of the most congested cities in the world due to a plethora of motor vehicles used in the city. One of the government actions to address the issue is by implementing Bus Rapid Transit (BRT) as an alternative public transportation mode. However, according to the convenience walking distance standard, the BRT coverage the inhabitant to choose motor vehicle rather than walking. This paper purposes Bike-Sharing as the smart transportation mode to overcome such issue and predict the three potential places to establish sharing-bike stations according to the convenience walking distance standard. In this paper the walking distance is classified into 100 mater range (300 meter, 400 meter and 500 meter) projected using the euclidean distance principle. As the result for 300 meter standard, there are 809 potential bike-sharing stations consist of 164 main stations and 645 feeder stations, while the 400 meter standard needs 541 potential stations with 140 stations serve the BRT station directly and 401 stations as the feeder. Furthemore, with 500 meter standard, 359 stations consist of 131 main stations and 228 feeder stations is needed.
Neonatal hyperbilirubinaemia necessitating exchange transfusion due to maternal sickle cell crisis
Authors: Ambulkar Hemant , Bhat Ravindra , Greenough Anne
Published: September 2019

Background

Pregnancy in women with sickle cell disease (SCD) is associated with a number of fetal complications such as intra-uterine death, intra-uterine growth restriction (IUGR), preterm birth, low birth weight and an increased perinatal mortality and morbidity. Hyperbilirubinaemia necessitating exchange transfusion in an infant of a mother with SCD, to the best of our knowledge, has not been previously described.

Case presentation

An infant was delivered at 33 weeks and 5 days of gestation due to a maternal sickle cell crisis. The infant had an unconjugated bilirubin level of 153 μmol/L on admission to the neonatal intensive care unit at 30 min of age. Phototherapy was immediately commenced, intravenous immunoglobulin administered and then a double-volume exchange transfusion was performed. There was, however, no evidence of haemolysis in the infant and the infant’s haemoglobin level remained stable following the exchange. No further exchange transfusions were required. The mother had a high unconjugated bilirubin level (151 μmol/L) prior to delivery.

Conclusion

High neonatal unconjugated bilirubin levels necessitating exchange transfusion can occur due to haemolysis in the maternal circulation, in this case due to SCD.
Wärmemessung bei Fermentreaktionen
Authors: Ohlmeyer Paul
Published: September 2019

Es wird ein Calorimeter beschrieben, das 50 bis 250 Milligrammealorien pro Stunde zu messen erlaubt. Die Wärmetönung der phosphatatischen Reaktion Adenosinmonophosphorsäure -> Adenosin + Phosphorsäure wurde zu - 1600 cal/mol bestimmt. Für die Wärmetönung der Reaktion Adenosintriphosphorsäure -• Adenosinmonophosphorsäure + 2 Phosphorsäure wurden in Übereinstimmung mit andersartigen Messungen von O. Meyerhof -24000 cal/mol gefunden. Die Messung der Reaktion Fumarat + Wasser -> l (-)-Malat ergab -3800 cal/mol, die Messung der Rückr^aktion + 3900 cal/mol. Aus diesen Werten in Zusammenhang mit dem Temperaturkoeffizienten der Gleichgewichtskonstante folgt für das System der Fumarase die Einstellung eines thermodynamischen Gleichgewichts, für das Ferment also die Natur eines echten Katalysators
Notiz zur Thermochemie des Bors
Authors: Roth W. A.
Published: September 2019

Abstrakt

Zwei moderne Arbeiten über die Bildungswärmen von glasigem B2O3 werden kritisch durchgerechnet; mit Hilfe der verbesserten Werte werden die Bildungswärmen der bisher thermisch untersuchten Borverbindungen neu berechnet und mit den Werten für analoge Verbindungen der Nachbarelemente verglichen
Zur Bose-Statistik (Nachtrag)
Authors: Schubert Gerhard
Published: September 2019

Zu der kürzlich 1 abgeleiteten Erweiterung der B o s e -Verteilungsfunktion um Glieder der Ordnung 1 /N (N = Teilchenzahl) wird eine Ergänzung gebracht.
Das Trennrohr mit hohem Druck und radialem elektrischen Feld 1 II. Erscheinungen der Turbulenz
Authors: Becker Erwin Willy
Published: September 2019

1. Der Entmischungsvorgang im Clusius-Dickelsehen Trennrohr wird erstmalig bei hohem Druck im Bereich von 1-26 atm untersucht (Wandabstand = 4,2 mm). Es zeigt sich, daß die Turbulenz besonders bei hohem Druck die Trennschärfe des Rohres gegenüber der Erwartung nach der laminaren Theorie außerordentlich vergrößert. Die Verbesserung der Trennschärfe wird durch eine Verminderung des Transportes so kompensiert, daß die Energieausbeute von turbulenter und laminarer Entmischung übereinstimmen. Die Tur-bulenz läßt sich in den laminaren Trennrohrformeln durch Einführung eines effektiven Wandabstandes berücksichtigen.

2. Die Wirbelbildung bei hohem Druck kann mit einem radialen elektrischen Feld stark beeinflußt werden. Im außen geheizten Trennrohr wird sie durch Elektrostriktions-kräfte vermindert, im innen geheizten dagegen verstärkt. Bei dem als Modellgas verwendeten Stickstoff-Kohlensäure-Gemisch unter 16 atm Druck kann der Wirkungsgrad der Trennung durch die Kombination von Turbulenz und Feld gegenüber den optimalen laminaren Verhältnissen verbessert werden. I m ersten Teil dieser Arbeit 1 wurde die Frage
Ergebnisse der Tieftemperaturforschung
Authors: Clusius Klaus , Wolf Gerhard
Published: September 2019

1. Es wird ein Goldkalorimeter beschrieben, in dem die kalorischen Eigenschaften von DCl, DBr und DJ zwischen 15° abs und dem Siedepunkt untersucht werden. 2. Die Reindarstellung dieser Gase und eine Anordnung zu ihrer Rektifikation wird angegeben. 3. Die wichtigsten Ergebnisse sind in Tab. 1 zusammengestellt und werden mit den entsprechenden Resultaten für die leichten Verbindungen verglichen. Es ergaben sich für das "normale" Verhalten der deuterierten gegenüber den leichten Verbindungen folgende Regeln: a) Die Molwärme der D-Verbindung liegt an entsprechenden Stellen der Molwärmenkurve im festen und flüssigen Zustand höher als die der II-Verbindung, b) Die Schmelztemperatur der D-Verbindung liegt um einige Zehntel-grade tiefer, ihre Schmelzwärme ist um einige cal kleiner als die der H-Verbindung, c) Der Tripelpunktsdruck der D-Verbindung ist 5 bis 15% kleiner als der der H-Verbindung. d) Die Umwandlungstemperaturen liegen bei den D-Verbindungen einige Grade höher, die Umwandlungswärmen sind um etwa 10% größer als bei den H-Verbindungen. - Das auffallendste Ergebnis, daß HBr drei, DBr dagegen nur zwei Umwand-lungspunkte zeigt, ist vor kurzem eingehend erörtert worden .

4. Schlieβlich werden noch die kalorischen und statistischen Entropien von DBr und DJ bei einer Atmosphäre Druck am Siedenpunkt miteinander vergleichen:
Zur Theorie der Diffusionspumpe
Authors: Jaeckel Rudolf
Published: September 2019

Im Anschluß an die grundlegenden Veröffentlichungen von Gaede werden im folgenden die physikalischen Vorgänge in der Diffusionspumpe theoretisch behandelt und an der Öldiffusionspumpe von Jaeckel-Schröder geprüft. Die Formeln für die quantitative Erfassung der physikalischen Vorgänge in den Pumpen werden in 1. und 2. Näherung aufgestellt. Auf Grund dieser Formeln ist es möglich, 1. die Leistungen von Diffusionspumpen zu berechnen, 2. die Dimensionierung einer Diffusionspumpe für eine bestimmte Leistung im voraus festzulegen.
Über elektrische Wellen längs eines dielektrischen Zylinders in einer dielektrischen Umgebung, wobei eines oder beide der beiden Medien Plasmen sind
Authors: Schumann Winfried Otto
Published: September 2019

Es wird die Ausbreitung elektromagnetischer Wellen längs Kreiszylindern untersucht: 1. Dielektrischer Zylinder in Plasmaatmosphäre, 2. Plasmazylinder in dielektrischer Atmosphäre, 3. Plasmazylinder in Plasmaatmosphäre. Ferner werden die stehenden Wellen (Eigen-schwingungen) untersucht, die durch zwei ebene, leitende Wände senkrecht zur Zylinderachse erzeugt werden. Infolge der Dispersion der Dielektrizitätskonstante eines Plasmas und der Tatsache, daß diese auch negativ werden kann, ergibt sich eine Vielzahl von Wellentypen, in den meisten Fällen die Möglichkeit einer Ausbreitung nur in endlichen, begrenzten Frequenzgebieten, und die Tatsache, daß die Phasengeschwindigkeit mit der Frequenz sowohl erheblich zu-als auch abnehmen kann. Am deutlichsten zeigt sich dies in Paradoxien des Verlaufs der Eigenfrequenzen des Systems des durch zwei Ebenen begrenzten Zylinders. Grenzflächenwellen mit geringer Phasen-und Gruppengeschwindigkeit und starker Energiekonzentration unmittelbar an der Grenzfläche Zylinder-Außenraum sind in allen Fällen möglich
Zur Stabilisierung der photochemischen Reaktionsprodukte in Ionenkristallen
Authors: Pick Von H. , Pohl R.W.
Published: September 2019

Durch Vergleich des photographischen Elementarprozesses mit photochemischen Dissoziationsprozessen an Alkalihalogeniden und MgO werden die Gründe für die Eignung des AgBr als photographische Grundsubstanz besprochen.
Die Löslichkeit von Bromsilber in komplexbildenden Lösungsmitteln
Authors: Jahn E.L. , Staude H.
Published: September 2019

Die Löslichkeit von AgBr wird mittels einer verbesserten Methode, die eine größere Genauigkeit zuläßt, in Natriumsulfit-Lösungen in Abhängigkeit von der Temperatur zwischen 2° C und 50° C bestimmt. Aus den erhaltenen Werten wird die Reaktionswärme, die Reaktionsarbeit und die Reaktionsentropie berechnet.
Über die Fehlerverteilung bei der photometrischen Bestimmung von Isotopenhäufigkeiten
Authors: Mattauch Josef
Published: September 2019

Bei der mit H. Ewald ausgearbeiteten photometrischen Methode der Messung relativer Isotopenhäufigkeiten gelangte ausschließlich eine bestimmte mit Hilfe von J. Eggert entwickelte Plattensorte der Agfa zur Verwendung. In der vorliegenden Arbeit wird an Hand des recht umfangreichen Beobachtungsmateriales die Verteilung der Streuung der nach dieser Methode gemessenen Isotopenhäufigkeiten untersucht und mit der Theorie der zufälligen Fehler verglichen. Es ergibt sich, daß der Fehler der Streuung etwa j 2-mal größer war, als theoretisch zu erwarten ist. Die plausibelste Annahme scheint zu sein, daß jeweils nur die Hälfte der Einzelbeobachtungen eines Häufigkeitsverhältnisses statistisch unabhängige Fehler zeigen, d. h. daß z. B. die Fehler von zwei aufeinanderfolgenden Beobachtungen genau die gleichen sind. Da die statistischen Fehler sicher zum größten Teil durch Inhomogenitäten der photographischen Schicht hervorgerufen werden, wäre der gefundene Effekt zu verstehen, wenn die Durchschnittsgröße der jeweils als homogen anzusehenden Bezirke so ist, daß durch sie im Durchschnitt die Intensitäten entsprechender Linien von zwei aufeinanderfolgenden Aufnahmen in der gleichen Weise beeinflußt werden.
Das Termsystem eines Ions mit zwei d-Außenelektronen in einem Feld oktaedrischer Symmetrie Farbe und Konstitution von Komplexverbindungen 3. Mitteilung
Authors: Ilse Friedrich Ernst , Hartmann Hermann
Published: September 2019

Es werden die Verschiebungen und Aufspaltungen der Terme eines Ions mit zwei d-Elektronen als Außenelektronen in einem elektrischen Feld oktaedrischer Symmetrie gruppen-theoretisch und unter Anwendung von Störungsrechnung untersucht.
Über die Lichtabsorption komplexer Ionen des dreiwertigen Vanadins mit oktaedrischer Symmetrie
Authors: Hartmann Hermann , Schläfer Hans Ludwig
Published: September 2019

Die Lichtabsorptionseigenschaften einer Reihe von Lösungen der Komplexionen des dreiwertigen Vanadins vom Typus [V A6]3+, wo A H2O, CH3OH, C2H5OH sowie iso-C4H9OH ist, wurden gemessen. Ferner wurden die Absorptionsspektren von kristallisiertem Ammonium-sowie Caesiumvanadin(III)-alaun aufgenommen.

Intensitätsverhältnisse und spektrale Lage der in allen Spektren auftretenden langwelligen Banden stehen in guter Übereinstimmung mit den Aussagen der Theorie für den Fall eines Zentralions mit zwei d-Elektronen bei Oh-Symmetrie des Komplexfeldes.
Sauerstoffisotopieeffekte und Hydratstruktur von Alkalihalogenid-Lösungen in H2O und D2O / Oxygen Isotope Effects and Hydrate Structure of Alkali Halide Solutions in H2O and D2O
Authors: Götz D. , Heinzinger K.
Published: September 2019

The fractionation of the oxygen isotopes in solutions of LiCl, NaCl. KCl, KBr, KJ and CsCl with H2O and D2O as solvent has been measured at 25 °C by means of the CO2-equilibration technique. As opposed to earlier measurements a slight anion dependence for the potassium halides has been found in H2O. This anion effect is much more pronounced in D2O. It even leads to a change in the directions of the 180 enrichment between cationic hydration water and bulk water for KCl and KBr. The absolute values of the fractionation factors for LiCl and CsCl, which differ in sign in H2O in agreement with positive and negative cationic hydration, respectively, as known from other kinds of measurements, is increased for LiCl and decreased for CsCl in D2O. There is no fractionation of the oxygen isotopes between hydration water and bulk water in both solvents for NaCl.

The solvent isotope effect is explained by the stronger anion influence on the structure of the bulk water in D2O as compared with H2O. This stronger influence is expected because of the higher structural order in D2O than in H2O at the same temperature.
Influence of the Environment on Proton Transfer in Symmetrical Hydrogen Bonds
Authors: Weidemann E. G. , Zundel G.
Published: September 2019

Symmetrical hydrogen bonds with a double minimum potential well or a largely flat potential are extremely easily polarisable, which leads to strong mutual interactions of such bonds and to interactions of the bonds with their environment. Particularly in the range of the rearrangement frequencies of the medium, the interactions depend to a marked extent on the fluctuation frequencies of the electromagnetic field and thus on the tunelling frequency of the proton in the hydrogen bond. On the other hand, the tunnelling frequency decreases due to the interactions. The correlation of the proton movements in two adjacent symmetrical hydrogen bonds and the resulting decrease of the tunnelling frequency is studied for the lowest group of levels. In addition, the decrease of the tunnelling frequency due to the effect of ion and dipole fields is calculated. In the tunnelling approximation the result depends in both cases on simple dimensionless parameters and indicates delay of the proton transfer in the bonds, but not complete hindrance. The lingering times in the potential wells are simply connected in both cases with the transition frequencies of the systems.
Identification of Thorium-236
Authors: Kaffrell N. , Trautmann N.
Published: September 2019

The new nuclide 236Th has been produced via the (γ, 2 p) reaction by irradiation of 238U with 140 MeV bremsstrahlung. After chemical separation of thorium, the half-life was determined to be 36 ± 3 min -from the growth-decay curve of the strongest γ-ray transition of the daughter nuclide, 9 min 236Pa.
Kinetics of the Ce3+/BrO2-Reaction in Sulfuric Acid Medium
Authors: Försterling H. D. , Lamberz H. J. , Schreiber H.
Published: September 2019

The reaction of Ce3+ with BrO2 in sulfuric acid solution (which is the starting step in the inorganic reaction subset of the Belousov-Zhabotinsky-reaction) is followed spectroscopically in a reaction mixture containing BrO2 at constant concentration. From first order kinetics (Br02 in excess) the rate constant for this reaction is evaluated.
Evaluation of Partial Structure Factors in the Small Q-Region with Amorphous Ni80P20 by Neutron Diffraction Using Isotopic Substitution
Authors: Schild K. , Frisius F. , Lamparter P. , Steeb S.
Published: September 2019

Amorphous Ni80P20-alloys were produced under He-atmosphere by the melt spin technique. With three specimens produced from P with natNi, 62Ni and 0Ni elastic scattering expriments were performed using neutrons with l = 5.4 Å in the Q-region 6 · 10−3 Å−1 ≦ Q ≦ 2.7 · 10−1 Å−1 . The measured intensities were corrected for absorption and background, desmeared, and normalized. The partial Bhatia Thornton structure factors SNN, SCC, and SNC w e r e evaluated and allowed the following conclusions: The a-Ni80P20-alloy contains regions with radii of about 6.5 Å caused by concentration fluctuations. A method is presented which allows to determine the composition of the regions and the total content of regions within the specimen. In the small Q-region (6 · 10−3 Å−1 ≦ Q ≦ 4 · 10−2 Å−1) the run of the partial structure factors is proportional to Q−3caused by concentration- and density-fluctuations. From the partial Fourier transforms follows a slight anisotropy concerning the chemical arrangement with correlation lengths elongated along the ribbon direction.
Konformationsuntersuchungen an Tetrahydroisochinolin- und Tetrahydronaphthalin-Semichinonen durch ESR-Spektroskopie
Authors: Scheffler Klaus , Stolze Klaus , Stegmann Hartmut B.
Published: September 2019

Semiquinones of 6,7-dihydroxy- 1,2,3,4-tetrahydroisoquinolines and -naphthalenes are investigated by ESR-spectroscopy in the presence of diorganothalliumhydroxide. The ESR-spectra show a significant temperature dependence of the coupling constants of the β-methylene protons due to ring inversion of the partially hydrogenated ring. Computer simulation of the spectra gave the rate constants and the activation parameters for this ring inversion process. The heterocyclic compounds show considerably lower rate constants due to implication of N-inversion. In comparison to analogous cyclohexene-semidione systems, our systems showed rate constants about 10 times higher than those of their monocyclic counterparts.
El acuerdo de pesca entre la Unión Europea y el reino de Marruecos y su protocolo de aplicación 2018-2022 a la luz de la última jurisprudencia del TJUE y del derecho internacional
Authors: Iglesias Berlanga Marta
Published: September 2019

Este trabajo examina, desde una perspectiva crítica, la celebración del Acuerdo de colaboración de pesca sostenible entre la Unión Europea (UE) y el Reino de Marruecos y su Protocolo de aplicación 2018-2022 a la luz, fundamentalmente, de: 1) la sentencia del Tribunal de Justicia de la Unión Europea (TJUE), de 27 de febrero de 2018, en el caso C-266/16, cuyo origen se remonta a una petición de cuestión prejudicial por parte del Tribunal Superior de Justicia (Inglaterra y País de Gales) de 2016, con respecto a la validez del Acuerdo de Colaboración de 2007 y de su Protocolo de aplicación 2014-2018, y de sus correspondientes actos de Derecho derivado; y 2) del Derecho internacional, en particular, a tenor de la aplicación territorial de los tratados y del principio de soberanía permanente sobre los recursos naturales.
Energy flow analysis and the study of Manihot esculenta Crantz
Authors: Morán Emilio F.
Published: September 2019

Abstract This paper makes use of energy flow language. It discusses how this energetics approach can be useful in research having to do with the interactions between man and the environment. All life processes have energy as their common denominator. The paper shows how this methodological approach aids in field preparation, organizes research while in the field and helps in the analysis of data. A discussion of manioc as an essential plant for man in the tropics is presented, and the myths surrounding the plant are indicated and recent research finds put in context. The potential of manioc as a food of the future is presented and suggestions are made for an energetics approach to the plant in situ. The plant's potential needs to be studied in the context of the real world in which tropical man utilizes it. Energetic models are presented as guides to the study of the plant as a system producing food.
A Trema micrantha (L) Blume como matéria-prima para a produção de celulose
Authors: Ribeiro Eloy Barbosa Penna , Luz Claudio Nazareno Reis
Published: September 2019

Sinopse São fornecidos dados sobre o estudo da Trema micrantha (L) Blume [Trema miocrantha, 1852], do ponto de vista de celulose e papel: obtenção de pasta química pelo processo Sulfato modalidade Soda-Enxofre; ensaios de alvejamento pelos processos CEHH, CED, CEDPD; resultados dos testes físico-mecânicos; análises químicas de madeira e estudo micrométrico. Essa essência é apresentada como uma espécie equivalente ou melhor que o Eucalyptus saligna para a obtenção de pasta química.
O ERRO COMO MEIO DE PRODUÇÃO DE CONHECIMENTO: MAX WEBER E A ENTWICKLUNGSGESCHICHTE
Authors: Freitas Renan Springer de
Published: September 2019

Resumo: A ideia de que erros bizarros podem conduzir a grandes acertos não é estranha à história da ciência. Este artigo examina o esforço realizado por Wolfgang Schluchter no sentido de mostrar que um determinado erro de Max Weber conduziu a um grande acerto - em razão de ter sido produzido nos marcos de uma perspectiva metateórica que conduz erros a acertos, a perspectiva "histórico-desenvolvimental" (Entwicklungsgeschichte). O erro: aplicar o conceito de "povo-pária" aos judeus da Antiguidade. Argumento de Schluchter: os historiadores mostraram que o conceito de "povo-pária" não se aplica aos judeus da Antiguidade, mas, não obstante, vale a pena insistir nesse erro porque ele conduz a um grande acerto: mostrar a importância da ruptura efetuada pelas missões Paulinas (com o particularismo judaico) para o desenvolvimento do racionalismo ocidental. Argumento do artigo: isto que Schluchter considera o grande acerto é apenas uma reverberação do pensamento teológico protestante do século XIX.
O DOM QUIXOTE DE ANTÔNIO JOSÉ DA SILVA, AS MARIONETES DO BAIRRO ALTO E AS PRISÕES DA INQUISIÇÃO
Authors: Chartier Roger
Published: September 2019

Resumo: Este estudo da peça Vida do grande Dom Quixote de la Mancha e do gordo Sancho Pança, de Antônio José da Silva liga três histórias: a história das adaptações teatrais da Segunda Parte de Dom Quixote, a história de uma prática teatral poucas vezes reconhecida, a do teatro de marionetes, situado entre o divertimento popular e a ópera, e a história de um dramaturgo, três vezes confrontado com a Inquisição e que viveu a dolorosa condição dos conversos às voltas com suas crenças íntimas e as permanentes suspeitas dos Inquisidores. O trágico destino de Antônio José da Silva oferece assim um caso limite para enfrentar a questão da relação entre as experiências de vida e as próprias obras.