bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlates of PDE5i Use Among Subjects with Erectile Dysfunction in Two Population-Based Surveys
Authors: Travison Thomas G. , Hall Susan A. , Fisher William A. , Araujo Andre B. , Rosen Raymond C. , McKinlay John B. , Sand Michael S.
Published: August 2011

Introduction

Erectile dysfunction (ED) is thought to affect some 150 million men worldwide, but many men with ED symptoms do not seek treatment. Existing surveys suggest that men with severe ED and who report support from their partners are more likely to receive treatment than were others. Less is known, however, concerning the influence of sociomedical factors such as income and body composition on receipt of treatment.

Aim

The aim of this study was to determine the importance of socioeconomic status, comorbidities, and body composition on receipt of treatment for ED symptoms.

Methods

We used data on 638 men enrolled in the Boston Area Community Health (BACH) survey reporting ED symptoms and/or treatment for ED as evidenced by phosphodiesterase type 5 inhibitor (PDE5i) use. Logistic regression was employed to assess the relative strength of association between receipt of treatment and socioeconomic factors, body mass index, and medical factors. A replication of these results was then provided via a parallel model using the 2004 follow-up of the Men's Attitudes to Life Events and Sexuality (MALES).

Main Outcome Measure

In BACH, ED was deemed present if a subject scored 16 points or fewer on the five-item International Index of Erectile Function or reported PDE5i use. In MALES, presence of ED was indicated by use of a validated single question querying ED severity.

Results

Controlling for age, body composition and other factors, increased household income, availability of a sexual partner, and provider diagnosis of high blood pressure were positively associated with treatment seeking via the use of PDE5i therapy in BACH. Results on data available in MALES produced similar results for household income and partner availability.

Conclusion

These data provide evidence that financial disadvantage may present a barrier to treatment of ED, an increasingly important sentinel marker of the cardiovascular and overall health among aging men.
The Effects of Chronic 5-Alpha-Reductase Inhibitor (Dutasteride) Treatment on Rat Erectile Function
Authors: Pinsky Michael R. , Gur Serap , Tracey Anthony J. , Harbin Andrew , Hellstrom Wayne J.G.
Published: August 2011

Introduction

Numerous clinical series have reported an association between 5-alpha-reductase inhibitors (5ARIs) and sexual dysfunction, but there are limited preclinical data available.

Aim

To further investigate the mechanisms of erectile dysfunction (ED) related to 5ARI therapy using a rat model.

Main Outcome Measures

Outcome measures include serum dihydrotestosterone (DHT), relaxant and contractile properties of cavernosal muscle, and nitric oxide synthase expression.

Methods

Twenty adult male Sprague-Dawley rats were randomized into control (N = 10) and dutasteride (0.5 mg/rat/day, in drinking water, N = 10) groups. Serum samples were obtained at baseline, from which DHT was measured after 30 days of treatment via radioimmunoassay (Beckman Coulter, Fullerton, CA, USA). Before the terminal blood draw, erectile response was measured using cavernosal nerve stimulation. The relaxant and contractile properties of cavernosal muscle strips were evaluated in tissue baths, and immunohistochemical (IHC) staining for nitric oxide synthase (NOS) and collagen deposition was performed.

Results

Mean serum DHT was suppressed by 86.5% (range 64.2–94.8%) after 30 days of 5ARI treatment and was statistically significant (P = 0.0024). In vivo erectile response in the dutasteride treated group decreased significantly compared with control (P < 0.001). While electrical field stimulation (EFS)-induced and acetylcholine-induced relaxation was decreased, EFS-induced and phenlyephrine-induced adrenergic contraction was significantly enhanced in the dutasteride group (P < 0.01). IHC studies demonstrated increased collagen deposition in the treatment arm as well as altered expression of neuronal NOS (nNOS) and inducible NOS (iNOS).

Conclusions

The 5ARIs, as demonstrated in these rat cavernosal smooth muscle studies, have a detrimental effect on erectile function. Enhanced iNOS expression may protect penile smooth muscle from fibrosis. The effect of 5ARIs on human sexual function warrants further investigation.
Synthesis, Cytotoxicity, and QSAR Study of New Aza‐cyclopenta[b]fluorene‐1,9‐dione Derivatives
Authors: Miri Ramin , Firuzi Omidreza , Peymani Payam , Zamani Meysam , Mehdipour Ahmad Reza , Heydari Zahra , Farahani Maryam Masteri , Shafiee Abbas
Published: August 2011

Thirty novel derivatives of aza‐cyclopenta[b]fluorene‐1,9‐dione were synthesized, and their cytotoxic activities were tested against HeLa, LS180, MCF‐7, and Raji cancer cell lines by MTT assay. Two derivatives containing nitrofuryl moiety, including 10‐(5‐nitro‐furan‐2‐yl)‐2,3‐dihydro‐4‐aza‐cyclopenta[b]fluorene‐1,9‐dione (IC50 range: 5.7–13.0 μm) and 10‐(5‐Nitro‐furan‐2‐yl)‐2,3,4,10‐tetrahydro‐4‐aza‐cyclopenta[b]fluorene‐1,9‐dione (IC50 range: 3.6–20.2 μm), as well as 10‐(2‐Nitro‐phenyl)‐2,3,4,10‐tetrahydro‐4‐aza‐cyclopenta[b]fluorene‐1,9‐dione (IC50 range: 3.1–27.1 μm) with nitrophenyl moiety on C10 position, were the most effective compounds. Furthermore, the effect of physiochemical descriptors on the cytotoxicity was evaluated by quantitative structure–activity relationship analysis. The quantitative structure–activity relationship results showed that molecular dipole moment, molar refractivity, fragment‐based parameters, and some topological indices were influential on the cytotoxic effect. Finally, the good correlation that was found among cytotoxic data obtained from different cell lines may be an implication of a common cytotoxic mechanism in these cell lines. These findings provide useful structural information for the rational design and synthesis of efficient chemotherapeutic agents for treatment for cancer.
Induction of Cell Death by a Novel Naphthoquinone Containing a Modified Anthracycline Ring System
Authors: Carvajal Denisse , Kennedy Steven , Boustani Andre , Lazar Monica , Nguyen Suong , DiCesare John C. , Sheaff Robert J.
Published: August 2011

The novel naphthoquinone adduct 12,13‐Dihydro‐N‐methyl‐6,11,13‐trioxo‐5H‐benzo[4,5]cyclohepta[1,2‐b]naphthalen‐5,12‐imine (hereafter called TU100) was synthesized as a potential chemotherapeutic agent. TU100 arrests tissue culture cells in S and G2/M phases of the cell cycle, followed by rapid induction of apoptosis. Evaluation by the Developmental Therapeutics Program at the National Cancer Institute revealed TU100 differentially inhibits growth of tissue‐specific human cancer cell lines and has in vivo efficacy in a hollow fiber assay. These data were evaluated against previously analyzed compounds using the COMPARE algorithm and predicted that TU100 has a unique mechanism of action. Further analysis revealed TU100 does not intercalate into DNA despite structural similarity to anthracyclines. Cells treated with the drug do exhibit DNA damage, however, as indicated by phosphorylation of histone H2A.X. This damage and effects on cell viability are likely mediated in part by TU100‐induced reactive oxygen species. Based on these results, TU100 shows promise as a chemotherapeutic drug owing to its unique structure, cellular targets, and efficacy against selected panels of tissue‐specific cancer cell lines.
Improving tracheostomy care: a prospective study of the multidisciplinary approach
Authors: Cetto R. , Arora A. , Hettige R. , Nel M. , Benjamin L. , Gomez C.M.H. , Oldfield W.L.G. , Narula A.A.
Published: August 2011

Clin. Otolaryngol. 2011, 36, 482–488

Objectives:  Suboptimal standards in tracheostomy care have been highlighted as a growing concern in view of the increasing demands for intensive care services. Our objective is to assess the impact of our model for tracheostomy care on patients with short‐term tracheostomies (<4 months in situ) following their discharge from the intensive care unit. The model has three components: The St Mary’s tracheostomy care bundle checklist, a dedicated tracheostomy multidisciplinary team and an educational programme.

Design:  A 38‐month prospective cohort study.

Setting:  A London Teaching Hospital.

Participants:  A total of 102 patients with tracheostomy within the 19‐month pre‐intervention cohort and 95 patients in the 19‐month post‐intervention cohort.

Main outcome measures:  The number of clinical incidents, mean time taken for decannulation, mean total tracheostomy time and total number of days spent in the intensive care unit were assessed before and after the intervention.

Results:  Time to decannulation following intensive care unit discharge decreased from 21 to 11 days, as did the mean total tracheostomy time, from 34 to 25 days (both statistically significant with a P < 0.0001 Mann–Whitney U‐test). The number of critical incidents, which included all patients prior to exclusion, substantially declined following the introduction of intervention from 58 to 7 in the second year after intervention.

Conclusions:  A multidisciplinary care model significantly expedited the decannulation process and reduced the overall time that a tracheostomy was in situ. The intervention was associated with a reduction in clinical incidents and shorter intensive care unit admissions, which can be associated with significant monetary savings.
A Nonionic Porphyrin as a Noninterfering DNA Antibacterial Agent
Authors: Mendes Sónia , Camacho Fábio , Silva Tito , Calado Cecília R. C. , Serra Arménio Coimbra , Rocha Gonsalves António M. d’A. , Roxo‐Rosa Mónica
Published: August 2011

The increasing interest in clinical bacterial photodynamic inactivation has led to the search for photosensitizers with higher bactericidal efficiency and less side effects on the surrounding tissues. We present a novel nonionic porphyrin, the 5,10,15‐tris(2,6‐dichlorophenyl)‐20‐[4‐N‐(6‐amino‐hexyl)sulfonamido)phenyl]‐porphyrin (ACS769F4) with substantial improvements in the efficiency of nonionic sensitizers. This porphyrin causes eradication of both Escherichia coli and Staphylococcus aureus by the photodynamic effect but in higher concentrations compared with 5,10,15,20‐tetrakis (4‐N,N,N‐trimethylammoniumphenyl)‐porphyrin p‐tosylate (TTAP4+), a known bactericidal tetracationic porphyrin. More important, under such conditions, ACS769F4 proved to be harmless to two mammalian cells lines (human embryonic and baby hamster kidney), causing no reduction in their viability or negative impact on their cytoskeleton, despite its accumulation in cellular structures. On the contrary, TTAP4+ is shown to accumulate in the nucleus of mammalian cells, in association to DNA, causing chromatin condensation after exposure to light. Furthermore, dark incubation with TTAP4+ was shown to have a deleterious effect on the microtubule network. Based on its bactericidal efficiency, also observed without exposure to light, and on the low tendency to be harmful or genotoxic to mammalian cells, ACS769F4 should be looked at as an interesting photosensitizer to be evaluated for clinical purposes.
How Work–Family Research Can Finally Have an Impact in Organizations
Authors: Kossek Ellen Ernst , Baltes Boris B. , Matthews Russell A.
Published: August 2011

Although work–family research has mushroomed over the past several decades, an implementation gap persists in putting work–family research into practice. Because of this, work–family researchers have not made a significant impact in improving the lives of employees relative to the amount of research that has been conducted. The goal of this article is to clarify areas where implementation gaps between work–family research and practice are prevalent, discuss the importance of reducing these gaps, and make the case that both better and different research should be conducted. We recommend several alternative but complementary actions for the work–family researcher: (a) work with organizations to study their policy and practice implementation efforts, (b) focus on the impact of rapid technological advances that are blurring work–family boundaries, (c) conduct research to empower the individual to self-manage the work–family interface, and (d) engage in advocacy and collaborative policy research to change institutional contexts and break down silos. Increased partnerships between industrial–organizational (I–O) psychology practitioners and researchers from many industries and disciplines could break down silos that we see as limiting development of the field.
Innovative Ideas on How Work–Family Research Can Have More Impact
Authors: Kossek Ellen Ernst , Baltes Boris B. , Matthews Russell A.
Published: August 2011

The commentaries on our focal article agreed with its main premise that work–family research should follow new strategies to improve its practical impact, and made suggestions clustering into three main themes. The first theme built on our suggestion to improve the research focus, terminology, and framing of work-family research. These essays offered additional ideas such as decoupling work-family from work-life research, and examining contextual factors more deeply. The second theme focused on how to better apply the findings from work family research. These commentaries provided social change approaches for making work-family issues more central to key stakeholders and to organizations. The third theme focused on broadening our scope to the societal level. These editorials advocated tactics supporting the development of basic rights of work–life balance within and across nations.
L‐tyrosine and L‐dihydroxyphenylalanine as hormone‐like regulators of melanocyte functions
Authors: Slominski Andrzej , Zmijewski Michal A. , Pawelek John
Published: August 2011

There is evidence that L‐tyrosine and L‐dihydroxyphenylalanine (L‐DOPA), besides serving as substrates and intermediates of melanogenesis, are also bioregulatory agents acting not only as inducers and positive regulators of melanogenesis but also as regulators of other cellular functions. These can be mediated through action on specific receptors or through non‐receptor‐mediated mechanisms. The substrate induced (L‐tyrosine and/or L‐DOPA) melanogenic pathway would autoregulate itself as well as regulate the melanocyte functions through the activity of its structural or regulatory proteins and through intermediates of melanogenesis and melanin itself. Dissection of regulatory and autoregulatory elements of this process may elucidate how substrate‐induced autoregulatory pathways have evolved from prokaryotic or simple eukaryotic organisms to complex systems in vertebrates. This could substantiate an older theory proposing that receptors for amino acid‐derived hormones arose from the receptors for those amino acids, and that nuclear receptors evolved from primitive intracellular receptors binding nutritional factors or metabolic intermediates.
Process Reliabilism and the Value Problem
Authors: JÄGER CHRISTOPH
Published: August 2011

Alvin Goldman and Erik Olsson have recently proposed a novel solution to the value problem in epistemology, i.e., to the question of how to account for the apparent surplus value of knowledge over mere true belief. Their “conditional probability solution” maintains that even simple process reliabilism can account for the added value of knowledge, since forming true beliefs in a reliable way raises the objective probability that the subject will have more true belief of a similar kind in the future. I argue that this proposal confronts significant internal problems and implicitly invokes higher‐level epistemic conditions that run against the spirit of externalism.
Reliability and Future True Belief: Reply to Olsson and Jönsson
Authors: JÄGER CHRISTOPH
Published: August 2011

In “Process Reliabilism and the Value Problem” I argue that Erik Olsson and Alvin Goldman's conditional probability solution to the value problem in epistemology is unsuccessful and that it makes significant internalist concessions. In “Kinds of Learning and the Likelihood of Future True Beliefs” Olsson and Martin Jönsson try to show that my argument does “not in the end reduce the plausibility” of Olsson and Goldman's account. Here I argue that, while Olsson and Jönsson clarify and amend the conditional probability approach in a number of helpful ways, my case against it remains intact. I conclude with a constructive proposal as to how their account may be steered in a more promising direction.
Australian New Zealand Clinical Trials Registry: history and growth
Authors: Askie Lisa M.
Published: August 2011

The problem of publication bias and the need for prospective trial registration to overcome this issue has been recognised for many years. Australia and New Zealand established a national clinical trials registry, the Australian New Zealand Clinical Trials Registry (ANZCTR, http://www.anzctr.org.au), in 2005. Much progress has been made over the past six years on this important research infrastructure resource, with the ANZCTR now housing over 5330 registered trial records. Recent reviews and initiatives have helped encourage prospective registration of Australian/New Zealand trials but several challenges remain. We continue to work to ensure all those interested in clinical trials being conducted in Australia and New Zealand (including consumers, clinicians, researchers, funders and regulators) are able to access information that is comprehensive, complete, current and compatible.
Thai Clinical Trials Registry
Authors: Tulvatana Wasee , Kulvichit Kittisak , Thinkhamrop Bandit , Tatsanavivat Pyatat
Published: August 2011

The Thai Clinical Trials Registry (TCTR) was established in 2009 by a group of university academics. The Thailand Center of Excellence for Life Sciences has supported the registry financially, while the basic infrastructure including the administration, staff and computer servers has been provided by the Clinical Research Collaboration Network and the Medical Research Foundation. In December 2010, the Ministry of Public Health of Thailand endorsed the registry. In addition to the major purposes of reducing publication bias, promoting research transparency, and reducing redundancy in clinical research, TCTR aims to create a collective database of the clinical researches in Thailand, in order to help construct a pool database for local researchers.
Low genetic diversity of symbiotic dinoflagellates (Symbiodinium) in scleractinian corals from tropical reefs in southern Hainan Island, China
Authors: ZHOU Guo‐Wei , HUANG Hui
Published: August 2011

Abstract  Endosymbiotic dinoflagellates in the genus Symbiodinium are among the most abundant and important group of photosynthetic protists found in coral reef ecosystems. In order to further characterize this diversity and compare with other regions of the Pacific, samples from 44 species of scleractinian corals representing 20 genera and 9 families, were collected from tropical reefs in southern Hainan Island, China. Denaturing gradient gel electrophoresis fingerprinting of the ribosomal internal transcribed spacer 2 identified 11 genetically distinct Symbiodinium types that have been reported previously. The majority of reef‐building coral species (88.6%) harbored only one subcladal type of symbiont, dominated by host‐generalist C1 and C3, and was influenced little by the host's apparent mode of symbiont acquisition. Some species harbored more than one clade of Symbiodinium (clades C, D) concurrently. Although geographically isolated from the rest of the Pacific, the symbiont diversity in southern Hainan Island was relatively low and similar to both the Great Barrier Reef and Hawaii symbiont assemblages (dominated by clade C Symbiodinium). These results indicate that a specialist symbiont is not a prerequisite for existence in remote and isolated areas, but additional work in other geographic regions is necessary to test this idea.
Exploring the Knowledge Strategies of Temporary Cluster Organizers: A Longitudinal Study of the EU Fabric Industry Trade Shows (1986–2006)
Authors: Rinallo Diego , Golfetto Francesca
Published: August 2011

abstract

Trade shows and other temporary clusters have recently emerged as key sites of theoretical relevance for scholars who are interested in the spatial consequences of interactive learning. Recent research has viewed these events as relational spaces in which countless actors interact and learn spontaneously without a central actor governing the process. In the case of permanent clusters, however, studies have started to unpack the practices through which key actors, such as entrepreneurial and professional associations, stimulate learning and interaction. In this article, we hold that these central subjects also have an important role in activating the benefits of colocalization with regard to temporary clusters. In an empirical study of the European Union clothing fabric trade shows between 1986 and 2006, we identified four types of practices through which trade show organizers shape learning and interaction at their events. Contrary to current views, our study found that exchanges of knowledge at these events do not always occur at the global level. Instead, the geographic scale of the processes of exchanging and acquiring knowledge in temporary clusters is socially and politically constructed at several levels—from the merely local to the truly global. We also found that organizers of trade shows facilitate vertical relationships between exhibitors and typical visitors (i.e., buyers), whereas other knowledge flows are neglected or even hindered. We conclude this article by highlighting the theoretical implications of our study for the literature on the spatial consequences of interaction and innovation.
Modeling and Simulation of a Mixing System With Water Saving Function
Authors: Corte-Real J. D. D. S. , Costa V. A. F. , Ferreira J. A. F.
Published: August 2011

This work focuses on the modeling and simulation of a mixing system for domestic use, which includes the water saving function. Water to be saved is the cold or partially cold water that reaches the mixing valve through the hot water inlet, as the tube length between the hot water source and the mixing valve is initially filled with cold water. Water saving function is obtained through a storage tank for accumulation of the initially cold or partially cold water, which is later used to feed the cold water inlet of the mixing valve. The accumulation system is designed such that accumulated water is preferably used than the cold water coming from the main cold water supply/distribution system to feed the cold water inlet of the mixing valve. Modeling considers fluid flow through the internal chambers of the system, the pressure evolution of water when flowing through the internal chambers of the system, and the temperature evolution of the separated and mixed water flows along the system. Simulation of the overall system is made using specialized tools to deal with stiff equations’ systems. Results show that, under real conditions, potable water savings of nearly 80% can be obtained relative to the water that is usually lost.
The Assessment of Melanoma Risk Using the Dynamic Infrared Imaging Technique
Authors: Pirtini Çetingül M. , Herman C.
Published: August 2011

Melanoma is the deadliest form of skin cancer. Each year more than 53,600 people learn that they have melanoma, and around 8700 people die from melanoma in the United States. Early detection is the key to improving survival in patients with malignant melanoma. We developed a thermal (infrared) imaging system that allows accurate measurements of small temperature differences on the skin surface with the aim to diagnose malignant pigmented skin lesions at an early stage of the disease. The imaging method we developed relies on active infrared imaging and a multimodal image analysis strategy, including involuntary body/limb motion correction and interactive lesion segmentation for detecting malignant lesions. The imaging system described in the paper was tested in a pilot patient study in which patients who possess a pigmented lesion with a clinical indication for biopsy were selected to participate. The lesion and the surrounding healthy skin were cooled by air at 15 °C for 30–60 s, and the thermal recovery was imaged with the infrared camera after the removal of this cooling stress. We found that the benign lesions have a thermal recovery similar to normal skin, whereas the thermal recovery of the melanoma lesion is different. It was observed that a malignant skin lesion has a higher temperature than healthy skin during the thermal recovery process (up to 2.2 °C higher for a Clark’s level II melanoma). The present study shows the feasibility of dynamic thermal imaging in distinguishing malignant pigmented lesions from benign, look-alike pigmented lesions.
Performance Predictions of a Moisture Management Device for Fuel Cell Applications
Authors: Killion Jesse D. , Garimella Srinivas , Determan Matthew D.
Published: August 2011

Moisture management in proton exchange membrane fuel cells is crucial to durability and performance. This frequently requires external humidification of the reactant gas streams to maintain sufficient humidity levels at the membranes, especially at higher operating temperatures. Direct-contact humidifiers using louvered fins brazed to rectangular tubes, similar to those frequently employed in automotive condensers and radiators, can be used to humidify a gas stream. A gas stream in which liquid water is sprayed flows through the passages formed by the louvered fins counter-current to a heating fluid flowing in the rectangular tubes sandwiching the fins. A mathematical model of this type of direct-contact humidifier is presented. The equations of energy and mass conservation are simultaneously solved for a number of segments along the humidifier. An equivalent resistance network is used to capture the temperature profile of the fins and liquid film surrounding them. The thickness of the liquid film is calculated from a shear balance at the film interface. The heat and mass transfer analogy is used with empirically derived transfer coefficients to solve the coupled heat and mass transfer problem in the gas phase. Predicted results are presented for typical operating conditions corresponding to a wide range of fuel cell operating conditions. The results show how the humidification process varies along the length of the humidifier. It is also shown that, although evaporation of the liquid film takes place throughout the entire humidifier, the direction of sensible heat transfer between the gas and liquid film can switch at some distance along the humidifier. This confirms the need for the equivalent resistance network model of the fin and film since simple fin efficiency models would fail in this situation. The model provides a basis for design optimization and performance predictions for this type of direct-contact moisture management device.
System-Level Metrics for Thermal Management Technology
Authors: Solovitz Stephen A. , Arik Mehmet
Published: August 2011

With the seamless advancements in modern electronics and shrinking thermal real estate, a number of candidate thermal technologies have been developed. As system designers evaluate these methods, they require unambiguous comparisons in order to properly assess the positives and negatives of advanced solutions. The most commonly used metrics, particularly thermal resistance, are limited in their applicability, especially because they account for only for single factors like the temperature of the heated device. To improve these comparisons, a new volumetric enhancement factor, EFv, is proposed, which can be justified based on lumped capacitance arguments. When coupled with the thermodynamic coefficient of performance, EFv allows a simple comparison that relates thermal performance, system input needs, and system size simultaneously. Using these metrics, several advanced technologies are compared, demonstrating that liquid cooling using microchannels can be in excess of 1000 times more effective than air cooling methods.
Study of Flow and Convective Heat Transfer in a Simulated Scaled Up Low Emission Annular Combustor
Authors: Patil Sunil , Sedalor Teddy , Tafti Danesh , Ekkad Srinath , Kim Yong , Dutta Partha , Moon Hee-Koo , Srinivasan Ram
Published: August 2011

Modern dry low emissions (DLE) combustors are characterized by highly swirling and expanding flows that makes the convective heat load on the gas side difficult to predict and estimate. A coupled experimental–numerical study of swirling flow inside a DLE annular combustor model is used to determine the distribution of heat transfer on the liner walls. Three different Reynolds numbers are investigated in the range of 210,000–840,000 with a characteristic swirl number of 0.98. The maximum heat transfer coefficient enhancement ratio decreased from 6 to 3.6 as the flow Reynolds number increased from 210,000 to 840,000. This is attributed to a reduction in the normalized turbulent kinetic energy in the impinging shear layer, which is strongly dependent on the swirl number that remains constant at 0.98 for the Reynolds number range investigated. The location of peak heat transfer did not change with the increase in Reynolds number since the flow structures in the combustors did not change with Reynolds number. Results also showed that the heat transfer distributions in the annulus have slightly different characteristics for the concave and convex walls. A modified swirl number accounting for the step expansion ratio is defined to facilitate comparison between the heat transfer characteristics in the annular combustor with previous work in a can combustor. A higher modified swirl number in the annular combustor resulted in higher heat transfer augmentation and a slower decay with Reynolds number.
Focused Evolution of HIV-1 Neutralizing Antibodies Revealed by Structures and Deep Sequencing
Authors: Wu Xueling , Zhou Tongqing , Zhu Jiang , Zhang Baoshan , Georgiev Ivelin , Wang Charlene , Chen Xuejun , Longo Nancy S. , Louder Mark , McKee Krisha , O’Dell Sijy , Perfetto Stephen , Schmidt Stephen D. , Shi Wei , Wu Lan , Yang Yongping , Yang Zhi-Yong , Yang Zhongjia , Zhang Zhenhai , Bonsignori Mattia , Crump John A. , Kapiga Saidi H. , Sam Noel E. , Haynes Barton F. , Simek Melissa , Burton Dennis R. , Koff Wayne C. , Doria-Rose Nicole A. , Connors Mark ,   NISC Comparative Sequencing Program, Mullikin James C. , Nabel Gary J. , Roederer Mario , Shapiro Lawrence , Kwong Peter D. , Mascola John R.
Published: August 2011

Broadly neutralizing antibodies to HIV with similar specificities can be found in multiple HIV-infected individuals.
Pyrazinamide Inhibits Trans-Translation in
Mycobacterium tuberculosis
Authors: Shi Wanliang , Zhang Xuelian , Jiang Xin , Yuan Haiming , Lee Jong Seok , Barry Clifton E. , Wang Honghai , Zhang Wenhong , Zhang Ying
Published: August 2011

The target of a first-line tuberculosis drug that acts against persister bacteria is identified.
Interpretation of electronic spectra of linear polynuclear p-quinones by the method of configuration analysis
Authors: Nepraš Miloš , Fabian Jürgen , Titz Miloš
Published: August 2011

Character of transition in a series of linear p-quinones has been investigated on the basis of configuration analysis. Correlation graphs of the states have been constructed enabling interpretation of the spectra in the terms of local transitions in the fragments and charge-transfer transitions between the fragments. Influence of various types of annelation on the first ππ* absorption band in the spectra of the mentioned compound class has been investigated qualitatively from the viewpoint of interaction of the frontier MOs of the fragments.
Theoretical study of electron structure and stability of quasiaromatic analogues of azulene
Authors: Zahradník Pavol , Ďurčíková Elena , Leška Jaroslav
Published: August 2011

Semiempirical CNDO/2 method was used in the study of 23 quasiaromatic azulene analogues containing a hydrogen bridge A..H-D, where A and D denote O, NH, or S. The values of the stabilization energy, interaction energy, and changes of Wiberg's indexes suggest that the stability of the studied compounds is caused by a strong hydrogen bond as well as by a strong delocalization of the π-electron system. Derivatives in which A and D are O and NH are especially stable. Derivatives containing an oxo or thio group are preferred in tautomeric equilibriums.
Catalytic activity of transition metals in hydrogenolysis of ethane calculated by the simplex method
Authors: Kuchynka Karel , Fusek Jiří , Štrouf Oldřich
Published: August 2011

The catalytic activity of transition metals in hydrogenolysis of ethane was approximated by a polynomial of second order with variables of basic physical importance, viz., molar heat capacity, covalent atomic radius of the metal, heat of melting, and first ionization potential of the metal atom. The physico-chemical significance of the correlation of these variables with the catalytic activity of transition metals is discussed.
Simplex search for mathematical representation of chemical class structure
Authors: Štrouf Oldřich , Fusek Jiří
Published: August 2011

A simplex algorithm useful in the search for the mathematical representation of the class structure is described. The use of this algorithm in combination with an appropriate pattern recognition classification method is discussed from the point of view of its application in chemistry.
Use of silica gel as a carrier of standards in the neutron activation analysis
Authors: Jiránek Václav
Published: August 2011

The optimum method of silica gel purification is described that makes possible its use as a carrier of standards in the neutron activation analysis. The achieved purity was checked by the instrumental neutron activation analysis. Silica gel was used as the carrier of Na, Br, Ba, Ca, Fe, Zn, Co, Cr, Sb, and Ni standards. The contribution of the carrier activity to the activity of the standard was less than 0.5%.
Mechanism of the Ullmann condensation
Authors: Vrba Zdeněk
Published: August 2011

It has been found that the condensation rate of 1-amino-4-bromoanthraquinone-2-sulphonic acid (I) with 1,3-diaminobenzene-4-sulphonic acid (II) giving 1-amino-4-(3'-amino-4'-sulphoanilino)anthraquinone-2-sulphonic acid (III) in media of NaHCO3-CO2 and NaHCO3-Na2CO3 with catalysis by CuI obeys the kinetic relation *u = k[I][II][Cu+][CO2-3], being controlled by the kinetic relation *u = k[I][II][Cu+]2[PO3-4] in media of NaH2PO4-Na2HPO4 buffers. The suggested reaction mechanism presumes formation of a bifunctional catalyst CuCO-3 or Cu2PO-4 which splits off the proton and bromide anion from the reaction intermediate in the rate-limiting step.
Symmetrical and unsymmetrical derivatives of distyrylbenzene
Authors: Arient Josef
Published: August 2011

The symmetrically substituted derivatives I-V of 1,4-distyrylbenzene have been prepared via the Horner reaction. A modification of the latter enabled preparation of unsymmetrical derivatives of 1,4-distyrylbenzene.
Preparation and absolute configuration at C(20) of 21-nor-5α-cholan-24→20-olide derivatives
Authors: Pouzar Vladimír , Havel Miroslav
Published: August 2011

The lactones X and XI were obtained on reaction of the aldehyde III with lithium salt of methyl propionate followed by hydrogenation of the intermediary esters IV and V. Treatment of the epoxides XXI and XXII with dilithium salt of acetic acid yielded the lactones X and XI. These lactones were also obtained by reaction of the epoxides XXI and XXII with sodium diethyl malonate through intermediates XXIII and XXV. The preparation of α-methylene lactones XXVII and XXVIII is also described. The 20R configuration was established for the lactones X, XXIII and XXVII while the lactones XI, XXV and XXVIII were assigned the 20S configuration both on the basis of 1H-NMR spectra and chemical correlations.
Fluorinated tricyclic neuroleptics with prolonged action: 3-Fluoro-8-trifluoromethyl derivatives of 10-(4-methylpiperazino)- and 10-[4-(2-hydroxyethyl)piperazino]-10,11-dihydrodibenzo-[b,f]thiepin
Authors: Šindelář Karel , Ryska Miroslav , Holubek Jiří , Svátek Emil , Metyšová Jiřina , Protiva Jiří , Protiva Miroslav
Published: August 2011

A reaction of (4-fluoro-2-iodophenyl)acetic acid with 4-(trifluoromethyl)thiophenol gave the acid VIII which was cyclized with the reagent consisting from methanesulphonic acid and phosphorus pentoxide and afforded the methanesulphonic enol ester XIX. The alkaline hydrolysis resulted in 3-fluoro-8-trifluoromethyldibenzo[b,f]thiepin-10(11H)-one (XVI) which was transformed via the alcohol XXIV to the chloro derivative XXV. Substitution reactions with 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine resulted in the title compounds IV and V. These products are very potent cataleptic neuroleptic agents with a prolongation of duration of the effects comparable to that of isofloxythepin and tefluthixol. A series of further synthetic experiments aimed at alternative syntheses of the acid VIII and the ketone XVI; their results were mostly not of use for preparative purpose but they led to isolation and characterization of a series of interesting heterocyclic products (XVII, XVIII, XXII, XXIII, XXIX-XXXI, XXXVI-XXXIX).
Synthesis and pharmacological screening of 1-[2-tert-aminoethyl]-8-fluoro-5-[4-fluorophenyl]-2,3,4,5-tetrahydro-1H-1-benzazepines, their 1-[aminoacetyl] analogues and 1-substituted 9-fluoro-6-[4-fluorophenyl]-5,6-dihydro-4H-s-triazolo[4,3-a]-1-benzazepines
Authors: Vejdělek Zdeněk , Svátek Emil , Holubek Jiří , Metyš Jan , Bartošová Marie , Protiva Miroslav
Published: August 2011

7-Fluoro-4-(4-flurophenyl)-1-naphthylamine (III) was identified as a by-product in the transformation of 7-fluoro-4-(4-fluorophenyl)-1-tetralone oxime to the lactam I. Reaction of 8-fluoro-5-(4-flurophenyl)-2,3,4,5-tetrahydro-1H-1-benzazepine (V) with chloracetyl chloride gave the chloramide VI which was treated with secondary amines to give the aminoacetamides VII, VIII, XI and XII. reduction with lithium aluminium hydride afforded the amines IX, X, XIV and XV. Acylation of the piperazinoethanols XII and XV led to the esters XIII, XVI and XVII. Reaction of the lactam I with phosphorus pentasulfide gave the thiolactam II which was treated with a series of acid hydrazides and gave the title compounds XVIII-XXIV. Some of the compounds exhibited only in relatively high doses anticonvulsant and central depressant effects in various tests.
Zur Hydrolyse von Trimetaphosphimat in alkalischen Lösungen
Authors: Töpelmann Werner , Thomas Berthold , Lehmann Hans-Albert , Mezník Lubomír , Novosad Josef , Dostál Karel
Published: August 2011

Der Verlauf der Hydrolyse von K- bzw. Na-Salzen des Trimetaphosphimats in alkalischen Lösungen wurde 31P-NMR-spektroskopisch verfolgt. Im Unterschied zu Angaben in der Literatur konnte während des bis zum Monophosphat führenden Abbaus das Auftreten einer Reihe verschiedener Zwischenprodukte nachgewiesen werden, von denen keines eine cyclische Struktur besitzt.
Calculations of quartet state spectra for diatomic species by INDO CI method including spin-orbit coupling perturbation
Authors: Minaev Boris F. , Zahradník Rudolf
Published: August 2011

Transition dipole moments for quartet-doublet transitions in diatomic species (NO, O+2 and CF) have been calculated on the basis of the INDO CI method and spin-orbit coupling (SOC) has been taken into account as a perturbation. Qualitative description of the first excited quartet and doublet states and occurrence of quartet states in photoelectron spectra are briefly discussed. The intensity and polarization of the components of the a4*P - X2*P transitions in NO and O+2 and the a4Σ- - X2*P transition in CF have been calculated. Fine structure constants (SOC constant A for 2*P and 4*P states, spin-rotation and zero-field splitting for the 4Σ- state) have been obtained and compared with experiment where possible.
Extraction of Am(III) by benzyldibutylamine from nitrate solutions of lanthanides
Authors: Vojtíšková Marta , Jedináková Věra , Kuča Libor
Published: August 2011

Benzyldibutylamine is a suitable extractant for the separation of Am(III) and Ln(III) from the acidic nitrate solutions. The effect of lanthanides and yttrium on the extraction of Am(III) has been followed under the conditions modelling the content of these components in the spent nuclear fuel. The separation factors αAm/Ln were evaluated for the optimum conditions found for the separation of Am(III) from the lanthanides. The coextraction of nitric acid and water into the organic phase is discussed.
Reactions of N-benzoyl isothiocyanate with anthranilic acid and methyl anthranilate
Authors: Kaválek Jaromír , Kotyk Milan , El Bahaie Said , Štěrba Vojeslav
Published: August 2011

N-Benzoyl-N'-(2-carboxy- and 2-methoxycarbonylphenyl)thioureas have been obtained by the reaction of N-benzoyl isothiocyanate with anthranilic acid and methyl anthranilate, respectively. Kinetics of cyclization of these compounds into 2-mercapto-3,4-dihydro-4-quinazolone have been studied in water and in methanol. In the base-catalyzed cyclization of N-benzoyl-N'-(2-carboxyphenyl)thiourea the proper cyclization is preceded by solvolysis of the benzoyl group. In the case of N-benzoyl-N'-(2-methoxycarbonylphenyl)thiourea the reaction rate is limited by the base-catalyzed cyclization of the starting benzoyl derivative; the benzoyl group is split off in a subsequent rapid step.
Preparation of high-molecular peptic acid by tomato pectinesterase
Authors: Markovič Oskar , Kohn Rudolf , Luknár Ondrej
Published: August 2011

Pectin was deesterified by pectinesterase of tomato either by the isolated enzyme or by the crude preparation, using a pH-stat and a continuous titration at pH 7.5 up to the esterification degree DE 2%. A simple procedure for preparation of high-molecular potassium pectate by enzymatic deesterification in a buffer solution of sufficient capacity was worked out. The final products of esterification degree DE = 10 ± 1% were obtained by immobilized pectinesterase of tomato. The molecular weight of the final products was identical with that of the original pectin.
Cross-reactivity study of oxytocin antibodies with oxytocin and its analogues modified in the cyclic part of the molecule
Authors: Hrbas Pavel , Slaninová Jiřina , Barth Tomislav , Franěk František
Published: August 2011

The specificity of oxytocin antibodies prepared by immunizing a pig with oxytocin that had been bound to thyreoglobulin by means of carbodiimide, was investigated using oxytocin analogues modified in position 1,2,4 and 6. All the modifications (deamination, substitution of sulfur in the disulfide bridge by a methylene group, methylation of the OH group of tyrosine or the substitution of the amino acid in this position and in position 4) resulted in analogues with a lower affinity to the antibodies than that of oxytocin.
[7-Glycine]deamino-1-carba-vasopressin: Synthesis and pharmacological properties
Authors: Brtník František , Barth Tomislav , Jošt Karel
Published: August 2011

[8-Arginine]deamino-1-carba-vasopressin and its 7-glycine derivative were prepared by condensation of the amino-terminal, cyclic part of the molecule with carboxy-terminal tripeptide amides. Replacement of proline by glycine in the position 7 results in a substantial decrease in the vasopressin-like activities, the oxytocin-like activities remaining unchanged.
Biological activity of some insulin derivatives
Authors: Šiševa Asja , Sirakov Ljuben M. , Slaninová Jiřina , Barth Tomislav
Published: August 2011

The ability of insulin and some of its derivatives to compete with 125I-insulin for the binding site in the membrane fraction prepared from the mammary gland of lactating mice is reported. The binding affinity decreased in the following order: insulin desoctapeptide-insulin tert-butyloxycarbonyl3-insulin tert-butyloxycarbonyl2-desoctapeptide-insulin. Insulin hexamethyl ester and its desoctapeptide in concentrations 5.5 . 10-11 - 2 . 10-5 M did not inhibit the binding of 125I-insulin. The comparison of the ability to decrease the blood glucose level showed that tert-butyloxycarbonyl3-insulin had 5% of the activity of insulin and that the other derivatives had less than 0.5% of that of insulin.
Viscosity of binary and ternary liquid nonelectrolyte mixtures. Derivation of correlation equations
Authors: Škubla Pavol
Published: August 2011

Equations for the correlation of viscosity of liquid binary and ternary mixtures were derived from the Eyring's theory of absolute reaction rates and from the three-molecule model of viscosity interactions. Another equation for the correlation of viscosity of binary mixtures was derived from the same theory and from the four-molecule model. Equations for the correlation of viscosity of binary and ternary mixtures were further derived from the quasi-crystalline model of liquids with the use of some relations of the kinetic theory of gases. The derived equations involve the same number of coefficients as the corresponding equations of McAllister or Chandramouli and Laddha and moreover are linear with respect to these coefficients.
Titration of sulphates and lead using lead ion selective electrode
Authors: Veselý Josef
Published: August 2011

Titration of sulphates with lead perchlorate employing lead ion selective electrode indication was studied using additions of various organic solvents at different pH' and ionic strength values. As the optimum emerged systems with 60-70% 1,4-dioxane, pH' 5.3-5.6. After dehydration with sodium hydroxide, dioxane must be freed from the electrode surface-oxidizing impurities by their reduction with sodium metal and subsequent distillation. The method was applied to determination of sulphates in mountain spring waters. Units of ppm can be determined; the limit of determination, however, depends considerably on the content of dioxane, total salt content in the sample, and speed of the semi-automatic titration. Lead can be determined with EDTA in concentrations down to c(Pb2+) = 5 . 10-6 mol l-1.
The role of electronic and steric effects in 29Si-NMR spectra of compounds with Si-O-C group
Authors: Schraml Jan , Chvalovský Václav , Mägi Märt , Lippmaa Endel
Published: August 2011

29Si-NMR chemical shifts are presented for several classes of compounds of general formula (CH3)4-n-mClnSi(OR)m (for n =0 m = 1-4 and for n = 1-3, m = 1). In most of the classes the shifts correlate linearly with polar constants of the substituents R or with Del Re net atomic charges on the silicon. The slopes in these correlations are all positive (i.e. the shielding decreases with electron withdrawal) and decrease with increasing n or m (i.e. the sensitivity of silicon shielding to substituent effects decreases with increasing number of electronegative substituents bonded to the silicon). This finding contradicts the available quantitative theories but can be accounted for by the qualitative model which considers back-bonding to silicon. Each methyl group in the γ position causes' a diamagnetic shift of 2 to 3 ppm, depending on the values of m and n, the effects are additive. Compounds with some heteroatoms in the γ position (R = CH2Cl, CH2Si(CH3)3, but not R = CH2Ge(CH3)3) behave anomalously, the origin of the anomalous shifts could not be ascertained.
NMR and quantum chemical study of empiric 2',3'-cyclic sulphites of nucleosides
Authors: Havlas Zdeněk , Synáčková Miroslava , Hřebabecký Hubert , Farkaš Jiří , Beránek Jiří
Published: August 2011

Quantum chemical calculations were applied to ethylene sulphite regarded as a model for the structures of 2',3'-cyclic sulphites of nucleosides. The structure of epimeric 2',3'-cyclic sulphites was investigated by spectroscopic methods including 1H-NMR, 1H-NMR with benzene-induced shifts and 13C-NMR. Five-membered cyclic sulphites are configurationally stable (barrier to inversion 180 kJ mol-1). The most stable conformation of the five-membered ring is represented by a twister envelope. According to 1H- and 13C-NMR measurements S configuration was assigned to those epimers of 5'-chloro-5'-deoxy-2',3'-sulphinyluridine and 5'-chloro-5'-deoxy-2',3'-sulphinyl-6-azauridine, which exhibit positive optical rotation. The both epimeric sulphites differ in the position and integral intensity of bands related to stretching vibrations of the S=O group. The epimer, which is more conformationally flexible (S configuration), is preferentially formed.