bluuebunny/crossref_metadata_2025 huggingface dataset:
Through a glass darkly: Cause and effect in refugee resettlement policies
Authors: Fass Simon M.
Published: July 2010

As the ongoing debate among philosophers and social scientists suggests, interpretation of cause and effect in human action is often extremely difficult. Especially complicated for the policy analyst is the problem of determining whether causal relationships are inferred from the evidence or imputed to it. This dilemma characterizes certain types of government activity in which distinctions between policy and implementation, between decisions and actions, and between inputs and outcomes are unclear. The efforts of the federal government between 1960 and 1985 to assist refugees in securing employment illustrate how the flow of events may elude causal explanation, and how conclusions and recommendation for improvement derived from the evidence may prove highly ambiguous. In such instances the most rational course open to policy analysts may be to concede ignorance.
Blind spots in policy analysis: What economics doesn't say about energy use
Authors: Stern Paul C.
Published: July 2010

This article describes the difficulties of reducing analysis of energy use to an application of economic theory. It shows how economic concepts of behavior direct attention selectively to some important determinants of consumer behavior and away from others; how available economic accounts of short‐term change in energy use, investment in energy efficiency, and the dynamics of investment limit understanding and narrow analysts' vision; how promising policy options are overlooked as a result; and how concepts and knowledge from the noneconomic behavioral sciences can compensate. Two strategies are discussed for improving analysis. Using economic theory to guide the improvement of existing models can help, conceptual blind spots will remain. A problem‐oriented approach drawing on concepts and methods from across the behavioral sciences can avoid the blind spots, but cannot be systematic. Analysis can be improved by using both approaches in concert; some implications of a combined strategy are sketched.
The political hand: Policy implementation and youth employment programs
Authors: Levin Martin , Fennan Barbara
Published: July 2010

Outstanding studies in the past decade have illuminated the sources of ineffective implementation and thus have suggested what not to do. To learn more about what to do, we analyzed a broad range of cases of effective implementation of youth employment programs in eight cities. The goal was to build an impressionistic model of the conditions contributing to flective implementation. We found that executives in the successful programs often acted as “fixers,” repairing the implementation process and protecting and correcting their programs, especially through coalition building and constant intervention in administrative detail. Some executives created patterns of interest convergence among the relevant actors, using incentives to turn mild interests into active support. They thus provided the public sector's missing “political hand,” analogous to the market's “invisible hand.”
Limits of the comprehensive services model: The case of adolescent pregnancy programs
Authors: Perlman Sylvia B. , Weatherley Richard A.
Published: July 2010

During the past 15 to 20 years a comprehensive services model, incorporating health, social, and educational components, has been the preferred mechanism for addressing the problems associated with adolescent pregnancy. This paper offers an assessment of the model based on a study of ten communities in four states. The widely recognized service needs of pregnant teenagers give the model a compelling logic, but we find inherent obstacles that seriously constrain its implementation. These constraints are exacerbated in an era of social welfare cutbacks. We conclude that short‐term local sewice programs, although better than no services at all, are unlikely to meet their objectives.
Negotiated rulemaking in practice
Authors: Perritt Henry H.
Published: July 2010

Until recently, parties interested in rulemaking by federal agencies were forced to voice their views primarily through adversarial procedures. An alternative, negotiated rulemaking, was proposed by the Administrative Conference of the United States (ACUS) in 1982. Since then, negotiated rulemaking has been used four times by federal agencies. The four completed negotiations show that negotiated rulemaking permits affected interests to retain greater control over the content of agency rules, while ensuring fairness and balance. It also permits agencies to obtain a more accurate perception of the costs and benefits of policy alternatives than can be obtained from digesting voluminous records of testimonial and documentary evidence presented in adversarial hearings. This article summarizes the results of a recently completed report prepared by the author for the Administrative Conference. It reviews the genesis of negotiated rulemaking, presents a framework within which to understand dynamics of the negotiation process and related administrative law issues, and presents recommendations for future agency use of negotiated rulemaking recently adopted in substance by the Administrative Conference.
Controllership in the public sector
Authors: Thompson Fred , Jones L. R.
Published: July 2010

Ineffective or incompetent controllership is, perhaps, the most common managerial failure found in the public sector. This failure affects outcomes and achievements in every area of public policy‐often profoundly. Controllers design and operate management control systems. The effectiveness of alternative control system designs depends upon the cost and production behavior of the good or service in question. But control strateg are seldom consciously or effectively matched to circumstances. As a consequence, public programs are too often simultaneously overcontrolled and out of control.
Federal tax reform and the financing of state and local governments
Authors: Chemick Howard , Reschovsky Andrew
Published: July 2010

Although the Reagan Administration tax reform proposals would reduce federal income tax liabilities for most taxpayers, federal tax reform would also create strong pressures on state and local governments to cut taxes and public services. These pressures would arise primarily because itemizers would no longer be able to deduct state and local taxes in determining their federal income tax liabilities. In New York City and Boston, it is likely that the Administration's tax reform would induce cuts in spending that range from 2.5 to 7.5 percent. While the elimination of state and local tax deductibility may promote allocative efficiency in the provision of local public goods, the cost would be a decline in the degree of redistribution through the state and local public sector, and a reduction in local public services for the poor.
Nonmoney income and the elderly: The case of the tweeners
Authors: Smeeding Timothy M.
Published: July 2010

This paper examines the degree of economic security experienced by the population aged 65 and over. Elderly people in the United States now enjoy an average degree of economic well being that is high relative to the younger population. Within that average there is variance, however. This analysis finds that elderly persons in the lower‐middle income range—within 100 and 200 percent of the poverty line—are economically more vulnerable than either those of high income or those below the poverty threshold. Virtually all of the elderly benefit from social security retirement income (OASI) and Medicare. The poor receive in addition substantial means‐tested cash and in‐kind transfers, and the well‐to‐do receive enough additional subsidies and tax‐free income to leave them better off after government intervention than before it. But those in between—the tweeners—are more likely to rent unsubsidized housing, are less likely to have non‐Medicare health subsidies, and are more likely to rely on OASI as their primary source of income. When facing economic or health problems, the only way they can improve their well being is to spend themselves down to penury and thereby qualify for means‐tested cash and in‐kind transfers, in the form of Medicuid and Supplemental Security Income. Policy implications of these findings are discussed in closing.
To pay or not to pay: A model of international defaults
Authors: Kohler Daniel F.
Published: July 2010

Most lenders in international financial markets accede to reschedule overdue payments when sovereign borrowers fail to meet repayment requirements rather than foreclose and force a default. This practice provides borrowers with strong incentives to avoid prompt payment and to sak rescheduling instead. Because lenders cannot distinguish between borrowers who are unable, and those who are merely unwilling, to repay the loan, they will agree to reschedule loans of borrowers who would choose to pay rather than face outright default. This paper augments the traditional lender‐borrower model by explicitly considering rescheduling, in addition to default and repayment, and places it in a game theoretic context. It develops a theory of unwillingness to pay, as opposed to inability to pay, and derives strategies by which lenders can at least partially protect themselves against rescheduling requests by borrowers unwilling, but not unable, to fulfill their obligation.
Ethics and education for the public service in a liberal state
Authors: Brown Peter G.
Published: July 2010

Graduate programs in public policy offer a variety of ethics courses focusing on framework theories, topical applications, and duties of office. Brown gives four reasons for making these types of courses an integral part of education for public service: they provide a common civic vocabulary; they give an essential perspective on analytical techniques; they challenge students' own presuppositions about public policy; and they help distinguish between empirical and conceptual issues. He argues that the growing emphasis in the policy programs on public management further enhances the importance of education in ethics, and that the current dearth of such courses in some programs seriously impedes their graduates.
Graduate education in public management: Working the seams of government
Authors: Elmore Richard F.
Published: July 2010

Public management means quite different things when it is understood in terms of its intellectual roots in policy analysis, in terms of what managers actually do in the public sector, and in terms of the knowledge and skills required for effective performance in higher‐level jobs in the public sector. As taught in the public policy schools, public management has inherited a deep skepticism about public intervention and an active decision‐forcing attitude toward the practice and teaching of management. These attributes distinguish it from public administration. The public management curriculum has developed in a number of different ways, and four broad models can be discerned from existing practice: the core survey model, the elective model, the modified MBA model, and the generic model. These models differ in several ways but share a common bias toward grounding in the technical core of management skills, a strong decision‐forcing emphasis, and an active view of the manager's role.
Privatization of public‐sector services in practice: Experience and potential
Authors: Poole Robert W. , Fixler Philip E.
Published: July 2010

Privatization—the transfer of assets and service responsibility from the public to the private sector—has been expanding at the state and local level. Empirical studies document significant cost savings, apparently due to incentives introduced by competition. The outlook is for continued expansion of privatization, including such areas as highways, transit, water supply, and education.
AID…Questions
Authors: Strong Paschal
Published: July 2010

As mentioned in our last issue, AID magazine and its editor Dr. Paschal Strong have given extensive support to the development of NSPI. The editorial reproduced below was printed in the August issue of AID. It brought to light several misunderstandings about the goals of NSPI which our president felt should be clarified. — Ed.
Substituent effect investigation of 3‐(2, 4‐dichlorophenyl)‐1‐(4′‐X‐phenyl)‐2‐propen‐1‐one. Part 1. Correlation analysis of 13C NMR chemical shifts
Authors: Perjéssy A. , Al‐Amood H. K. , Fadhil G. F. , Prónayová N.
Published: July 2010

A series of substituted chlorinated chalcones namely, 3‐(2,4‐dichlorophenyl)‐1‐(4′‐X‐phenyl)‐2‐propen‐1‐one, have been synthesized, X being H, NH2, OMe, Me, F, Cl, CO2Et, CN, and NO2. Dual substituent parameter (DSP) models of 13C NMR chemical shift (CS) have revealed that π‐polarization concept could be utilized to explain the reverse field effect at CO, the enhanced substituent field effect at CO, C‐2, and C‐5, and the decreased sensitivity of substituent field effect at C‐6. Chlorine atoms dipole direction at the benzylidene ring either enhances or reduces substituent effect depending on how they couple with the substituent dipole at the probe site. The correlation of 13C NMR CS of C‐2, C‐5, and C‐6 with σ and σ indicates that chlorine atoms in the benzylidine ring deplete the ring from charges. Both MSP of Hammett and DSP of Taft 13C NMR CS models give similar trends of substituent effects at C‐2, C‐5, and C‐6. However, the former fail to give a significant correlation for CO and C‐6 13C NMR CS. MSP of σq and DSP of Taft and Reynolds models significantly correlated 13C NMR CS of Cβ. MSP of σq fails to correlate C‐1′ 13C NMR CS. Investigation of 13C NMR CS of non‐chlorinated chalcones series: 3‐phenyl‐1‐(4′‐X‐phenyl)‐2‐propen‐1‐one has revealed similar trends of substituent effects as in the chlorinated chalcones series for C‐1′, CO, Cα, and Cβ. In contrast, the substituent effect of the non‐chlorinated chalcone series at C‐2, C‐5, and C‐6 did not correlate with any substituent constant. Copyright © 2010 John Wiley & Sons, Ltd.
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada
Authors: Stevens Christopher W. , Moorman Brian J. , Solomon Steve M.
Published: July 2010

Interannual changes in seasonal ground freezing and near‐surface heat flow beneath zones of bottom‐fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near‐shore zone of the Mackenzie Delta, Canada. Winter variability in ground thermal conditions was determined at three monitoring sites. Ground‐penetrating radar surveys were conducted in late winter to determine spatial variability in landfast ice conditions and the extent of ice‐bonded sediments. Shallow water sites (<0.5 m‐water depth) were characterised by early onset of BFI, freezeback of the active layer and mean winter sediment bed temperatures ranging between −3°C and −10°C. In contrast, deep water sites (>1 m of water) experienced prolonged periods of floating ice, which limited the duration of ice contact with the sediment bed and the depth of seasonal frost, and resulted in warmer winter ground temperatures (between −0.5°C and −2.6°C). Under similar water depths, interannual changes in ice growth altered the timing of BFI and winter heat loss from the ground. When comparing conditions over the two winters, 2005–06 was characterised by a decrease in ice thickness that limited the extent of BFI and seasonal cooling of the ground. These changes in ice conditions had a greater effect on the thermal conditions at sites where water depths were close to the maximum ice thickness. The short ice contact times at these sites are important to the thermal state of permafrost, as only minimal heat exchange contributing to permafrost cooling occurs prior to freezeback of the active layer. Copyright © 2010 John Wiley & Sons, Ltd.
Multifunctional cytotoxic agents fromAnacardium occidentale
Authors: Kubo Isao , Nitoda Teruhiko , Tocoli Felismino E. , Green Ivan R.
Published: July 2010

The effects of anacardic acids and cardols isolated from the cashew nut and appleAnacardium occidentale(Anacardiaceae) on murine B16‐F10 melanoma cells were tested. Although anacardic acids and cardols were found to inhibit tyrosinase, a key enzyme in melanin synthesis, melanogenesis in melanocytes was not suppressed in cultured cells but rather enhanced. Both anacardic acids and cardols exhibited moderate cytotoxicity. Copyright © 2010 John Wiley & Sons, Ltd.
Bromelain in the early phase of healing in acute crush Achilles tendon injury
Authors: Aiyegbusi A. I. , Duru F. I. O. , Anunobi C. C. , Noronha C. C. , Okanlawon A. O.
Published: July 2010

Bromelain, an enzyme extracted from the stem of the pineapple plant has been proposed as a treatment for reducing pain and swelling following acute muscle injuries but studies are yet to be done on its effect on tendon healing. This study therefore investigated the effects of bromelain on tenocyte proliferation and the tendon malondialdehyde (MDA) level in the early stage of healing in a crush injury to the Achilles tendon of Sprague‐Dawley rats.

Twenty four male rats were divided randomly into three groups; groups 2 and 3 had induced crush injury to the left Achilles tendon. Group 1; nil injury and nil treatment, Group 2; nil treatment, Group 3; oral bromelain treatment. Bromelain was given at a dosage of 7 mg/kg body weight daily over the first 14 days post‐injury. On day 15 post injury, the animals were killed and the tendons excised and processed for histological study and MDA assay.

The results showed a significant increase in the tenocyte population in the bromelain group; p < 0.05. There was, however, no significant difference in the MDA level.

Conclusion: Based on this study, 600 GDU bromelain given once daily in acute tendon injury at a dosage of 7 mg/kg promoted healing by stimulating tenocyte proliferation. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of food and gender on the pharmacokinetics of rhein and emodin in rats after oral dosing with Da‐Cheng‐Qi decoction
Authors: Gong Han Lin , Tang Wen Fu , Wang Hong , Xia Qing , Huang Xi
Published: July 2010

Da‐Cheng‐Qi decoction (DCQD), a traditional Chinese medicine preparation used to treat digestive diseases, is composed of dahuang (Rheum officinale Baill, Polygonaceae), houpu (Magnolia officinalis Rehd., Magnoliaceae), zhishi (Citrus aurantium L, Rutaceae) and mangxiao (sodium sulphate). Rhein and emodin are the major active components of Rheum officinale Baill. To investigate the effects of food and gender on the plasma concentrations of rhein and emodin after oral administration of DCQD, a rapid high‐performance liquid chromatographic method was developed and validated. A reversed phase C18 column (150 × 4.6 mm) and a mobile phase of methanol and 0.2% acetic acid (78:22, v/v) were employed with ultraviolet detection at 254 nm. Feeding was observed to decrease the absorption of rhein and emodin in rats receiving DCQD orally. No evidence for gender‐based differences in the pharmacokinetics of rhein was observed. However, the half‐life and area under the concentration–time curve for emodin differed significantly between male and female rats. Because food intake and gender are anticipated to influence the pharmacokinetics of DCQD in human subjects, it is recommended that oral doses of DCQD be reduced in fasting subjects and that female patients receive lower oral doses compared with male patients. Copyright © 2010 John Wiley & Sons, Ltd.
Anti‐heartburn effects of a fenugreek fiber product
Authors: DiSilvestro Robert A. , Verbruggen Marian A. , Offutt E. Jann
Published: July 2010

Frequent heartburn occurs in many people, some of whom prefer alternative treatments over conventional drugs. In a pilot study of subjects with frequent heartburn, 2 week intake of a fenugreek fiber product, taken 30 min before two meals/day, diminished heartburn severity. This conclusion was based on symptom diary results and reduced the use of a mild antacid as a rescue medicine. Improvement for each of the 2 weeks was judged by comparison with results from a baseline week. Placebo also produced some statistically significant effects, but the fiber product's effects differed significantly from the placebo. Moreover, the fenugreek fiber effects were generally similar to the results produced by an OTC antacid medication (ranitidine at 75 mg, twice a day). This study suggests that people with certain degrees of heartburn can benefit from a fenugreek fiber product. Copyright © 2010 John Wiley & Sons, Ltd.
Chloroform extract of aged black garlic attenuates TNF‐α‐induced ROS generation, VCAM‐1 expression, NF‐κB activation and adhesiveness for monocytes in human umbilical vein endothelial cells
Authors: Lee Eun Na , Choi Young Whan , Kim Hye Kyung , Park Jin Kyeong , Kim Hyo Jin , Kim Myoung June , Lee Hee Woo , Kim Ki‐Hyung , Bae Sun Sik , Kim Bong Seon , Yoon Sik
Published: July 2010

Aged black garlic is a type of fermented garlic (Allium sativum) which has been used in Oriental countries for a long time because of various biological properties of garlic derivatives. The current study explored the potential of the chloroform extract of aged black garlic (CEABG) in attenuating the activities of adhesion molecules in tumor necrosis factor‐α (TNF‐α)‐stimulated human umbilical vein endothelial cells (HUVECs). The study was performed on HUVECs that were pretreated with 30 μg/mL of CEABG before TNF‐α treatment. Treatment of HUVECs with CEABG significantly inhibited TNF‐α‐induced reactive oxygen species (ROS) formation. HUVECs treated with CEABG showed markedly suppressed TNF‐α‐induced mRNA expression of VCAM‐1, but little alteration in ICAM‐1 and E‐selectin mRNA expression. CEABG treatment also significantly decreased the TNF‐α‐induced cell surface and total protein expression of VCAM‐1 without affecting ICAM‐1 and E‐selectin expression. In addition, treatment of HUVECs with CEABG markedly reduced THP‐1 monocyte adhesion to TNF‐α‐stimulated HUVECs. Furthermore, CEABG significantly inhibited NF‐κB transcription factor activation in TNF‐α‐stimulated HUVECs. The data provide new evidence of the antiinflammatory properties of CEABG that may have a potential therapeutic use for the prevention and treatment of vascular diseases such as atherosclerosis through mechanisms involving the inhibition of VCAM‐1 expression and NF‐κB activation in vascular endothelial cells. Copyright © 2010 John Wiley & Sons, Ltd.
Theoretical study of the anthropogenic greenhouse gas (SF5CF3) and analysis of the reaction of SF6 with CF
Authors: Morgon Nelson H.
Published: July 2010

SF5CF3 was recently detected in the earth's atmosphere. This has lead to various experimental and theoretical studies aimed at establishing the properties of this molecule, from which to understand how it is formed, how it may impact on the atmosphere (it is a powerful greenhouse gas), and how it may be destroyed in the atmosphere. SF5CF3 is chemically very inert, and is not destroyed in the troposhere. Theoretical calculations using effective core potential (ECP) based on high‐level methods — QCISD(T), were performed for molecular systems related to SF5CF3. Existing values for the S–C bond dissociation energy in SF5CF3 span a wide range, from estimates of about 200 to 300 kJ mol−1, obtained from theoretical calculations on SF5CF3 using the DFT, G2, and G3 protocols, to 390 ± 45 kJ mol−1 derived from experimental studies of the photoionisation of SF5CF3. At the QCISD(T)/ECP + GCM (generator coordinate method) level, the dissociation energy ‐ Do (SF5 ‐CF3, 0 K), is 274.7 kJ mol−1. In addition to calculations on individual molecules, the reactions of SF6 with CF were studied. The first objective was to locate the reactant ion‐molecule complex, the transition state, and the product ion‐molecule complex for each of these systems. On the basis of literature thermochemistry, the reaction of SF6 with CF, in which the CF reactant anion abstracts F+ from SF6 to leave SF, is highly exothermic (−343 kJ mol−1). At the QCISD(T)/ECP + GCM level gives a value of −377.6 kJ mol−1. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Temperature dependence of the energetics and structure for the Ar dimer and trimer
Authors: Pérez De Tudela R. , Márquez‐Mijares M. , González‐Lezana T. , Roncero O. , Miret‐Artés S. , Delgado‐Barrio G. , Villarreal P.
Published: July 2010

A path‐integral Monte Carlo (PIMC) method has been used to investigate the dynamics of the Ar dimer and trimer with temperature. Energy and radial distributions are compared with estimates obtained from alternative approaches based on the calculation of the discrete and continuum rovibrational spectra of the two systems. The analysis of the Ar2 case reveals that the system only evolves between the equilibrium configuration and the breaking of the ArAr bond. This feature thus differs from the situation observed for the trimer in a previous study where the existence of a collinear isomer between the equilateral arrangement and the predissociative ArAr2 structure was manifested. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Hydrogen surface passivation of Si and Ge nanowires: A semiempirical approach
Authors: Miranda A. , Serrano F. A. , Vázquez‐Medina R. , Cruz‐Irisson M.
Published: July 2010

A semiempirical nearest‐neighbor tight‐binding approach, that reproduces the indirect band gaps of elemental semiconductors, has been applied to study the electronic and optical properties of Si and Ge nanowires (NWs). The calculations show that Si‐NWs keep the indirect bandgap whereas Ge‐NWs changes into the direct bandgap when the wire cross section becomes smaller. Also, the band gap enhancement of Si‐NWs showing to quantum confinement effects is generally larger than that of similar‐sized Ge‐NWs, confirming the larger quantum confinement effects in Si than in Ge when they are confined in two dimensions. Finally, the dependence of the imaginary part of the dielectric function on the quantum confinement within two different schemes: intra‐atomic and interatomic optical matrix elements are applied. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2448–2454, 2010
Multireference coupled‐cluster methods for ground and low‐lying excited states. A benchmark illustration on CH + potentials
Authors: Li Xiangzhu , Paldus Josef
Published: July 2010

Multireference (MR), general‐model‐space (GMS), state‐universal (SU) coupled‐cluster (CC) method that considers singly (S) and doubly (D) excited cluster amplitudes relative to the reference configurations spanning the model space (GMS SU CCSD), as well as its externally corrected (ec) version (N,M)‐CCSD that uses N‐reference MR CISD as an external source of higher‐than‐pair cluster amplitudes in a M‐reference GMS CCSD, are used to investigate low‐lying states of the CH+ ion. Relying on a simple ab initio model that enables a comparison with the exact full configuration interaction energies, the performance of the GMS‐based methods is assessed in the whole relevant range of internuclear separations. It is shown that the ec (N,M)‐CCSD version provides best results for both the singlet and the triplet states considered. For triplets, the use of high‐spin (MS = 1) references is to be preferred. The GMS‐based MR SU CC results for the ten low‐lying states of CH+ clearly indicate the usefulness and reliability of these approaches. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Structural and electronic study of neutral, positive, and negative small rhodium clusters [Rhn, Rh, and Rh]
Authors: Mora M. A. , Mora‐Ramírez M. A. , Rubio‐Arroyo Manuel F.
Published: July 2010

We have carried out a systematic study for the determination of the structure and the fundamental state of neutral and ionic small rhodium clusters [Rhn, Rh, Rh (n = 5–10)] using ab initio Hartree‐Fock methods with a LANL2DZ basis set. A range of spin multiplicities is studied for each cluster. We present the bond lengths and angles and geometric configuration adopted for the clusters in its minimum energy conformation showing the differences when the clusters have different number of unpaired electrons. In addition, we report the vertical ionization potential and the adiabatic potential calculated by the Koopman's theorem. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2541–2547, 2010
The QM/MM‐ER studies for the origin of the antioxidative properties of MCI‐186 in aqueous solutions
Authors: Takahashi Hideaki , Iwata Yuichi , Kishi Ryohei , Nakano Masayoshi
Published: July 2010

The anionic derivative of the pharmaceutical compound 3‐methyl‐1‐phenyl‐2‐pyrazolin‐5‐one (MCI‐186) is known to deactivate the free radicals in biological systems by donating its excess electron. For the purpose to investigate the mechanism that the MCI‐186 anion exhibits the antioxidative activity in aqueous solutions, we have performed a series of quantum mechanical/molecular mechanical (QM/MM) simulations based on the density functional theory in combination with the theory of energy representation (QM/MM‐ER). For the computational convenience, MCI‐186 has been modeled by 1,3‐dimethyl‐2‐pyrazolin‐5‐one (DMP) by substituting the phenyl group in MCI‐186 by a methyl one. We have applied the QM/MM‐ER approach to compute free energy change δGaqassociated with the electron detachment from DMP anion in water. To make comparisons, we have also performed the simulations for a natural radical scavenger, ascorbic acid modeled by 3,4‐dihydroxy‐furan‐2‐one (DHF). In the QM/MM‐ER approach, the distribution functions of the solute–solvent interaction energy, which serve as fundamental variables to describe the free energy, are to be constructed with the QM/MM force field. The free energy changes δGaqwere computed as 99.1, 108.3 kcal/mol for DMP and DHF anions, respectively, whereas that for hydroxyl anion OH−taken as a reference system was evaluated as 138.9 kcal/mol. Thus, it was revealed that the free energies δGaqfor DMP and DHF anions are much smaller than that for hydroxyl anion, which directly indicates the high activities of the molecules as electron donors. We found that the small δGaqvalues can be mainly attributed to the small values in the absolutes of the solvation free energies. The fractional charge analyses provided the evidence that the delocalization of the excess charge on the solute gives rise to the destabilization of these radical scavengers in the solute–solvent interaction. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Ab initio electron propagator methods: Applications to nucleic acids fragments and metallophthalocyanines
Authors: Zakrzewski Viatcheslav G. , Dolgounitcheva Olga , Zakjevskii Alexander V. , Ortiz J. V.
Published: July 2010

Electron propagator methods provide accurate and efficient determinations of electron binding energies and retain many interpretive advantages through their generation of associated Dyson orbitals. Methods that are based on the diagonal self‐energy approximation have been applied to nucleic acid fragments such as nucleotides and dinucleotides. These calculations can be made more feasible for larger systems through the introduction of quasiparticle virtual orbitals. Nondiagonal, renormalized self‐energies are needed for systems where correlation final states with low‐pole strengths are present. Applications to zinc phthalocyanine illustrate such capabilities. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Atomic radii in molecules for use in a polarizable force field
Authors: Swart Marcel , Van Duijnen Piet TH.
Published: July 2010

We report here the results for an ab initio approach to obtain the parameters needed for molecular simulations using a polarizable force field. These parameters consist of the atomic charges, polarizabilities, and radii. The former two are readily obtained using methods reported previously (van Duijnen and Swart, J Phys Chem A 1998, 102, 2399; Swart et al. J Comput Chem 2001, 22, 79), whereas here we report a new approach for obtaining atomic second‐order radii (SOR), which is based on second‐order atomic moments in scaled Voronoi cells. These parameters are obtained from quantum‐chemistry calculations on the monomers, and used without further adaptation directly for intermolecular interactions. The approach works very well as shown here for four dimers, where high‐level coupled cluster with singles and doubles, and perturbative triples (CCSD(T)) and density functional theory (DFT) Swart‐Solà‐Bickelhaupt functional including Grimme's dispersion correction (SSB‐D) reference data are available for comparison. The energy surfaces for the three methods are very similar, which is also the case for the interaction between a water molecule with either a chloride anion or a sodium cation. These latter systems had previously been used to criticize Thole's damped point‐dipole method, but here we show that with the correct use of the method, it is perfectly able to describe the intermolecular interactions. This is most obvious for the induced dipole moment as function of the chloride–oxygen distance, where the direct (discrete) reaction field results are virtually indistinguishable from those obtained at CCSD(T)/aug‐cc‐pVTZ. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Effect of Zn doping on the sublimation rate of pentaerythritol tetranitrate using atomic force microscopy
Authors: Mridha Subrata , Weeks Brandon L.
Published: July 2010

A series of Zn ion‐doped pentaerythritol tetranitrate (PETN) nanoislands in the form of thin films were prepared on Si substrates using spin coating. The effect of Zn concentrations on the sublimation energy was investigated by atomic force microscopy (AFM). The pure and Zn‐doped nanoislands are imaged by AFM in contact mode at room temperature after annealing isothermally for a given time. The volume of the islands starts to decrease after annealing at 45°C for pure PETN, whereas Zn‐doped nanoislands start to decrease in height and volume after annealing at 55–58°C. The minimum activation energy is found to be 29.7 Kcal/mol for 1,000 ppm Zn concentration. These studies are important for the long‐term stabilization of PETN. SCANNING 31: 181–187, 2009. © 2009 Wiley Periodicals, Inc.
Reflection confocal imaging of type I and type III isozymes of hexokinase in PC12 cells
Authors: Whallon Joanne H. , Preller Ana , Wilson John E.
Published: July 2010

Reflection confocal microscopy was used to determine the intracellular distribution of Type‐I and III isozymes of hexokinase (ATP:D‐hexose 6‐phosphotransferase, EC 2.7.1.1) in PC12 cells; detection was by staining with diaminobenzidine as a substrate for horseradish peroxidase‐conjugated antimouse immunoglobulins bound to isozyme‐specific monoclonal antibodies. With both isozymes, detection of the staining pattern was significantly enhanced by reflection confocal imaging compared with viewing with transmitted brightfield optics. For Type I, prominent staining of cytoplasmic organelles having a distribution consistent with that of mitochondria was noted. For Type III, intense staining at the nuclear periphery was observed. A distinct punctate pattern along the nuclear surface implied a nonuniform distribution of the Type III hexokinase and may represent preferential association with nuclear pore structures. A study of technical factors involved in optimizing the reflection image was conducted. We demonstrate that both the choice of objective and the thickness of the mounting medium are critical to successful imaging, and we describe a simple test for assessing the suitability of objectives in any system.
Electron microscopy of C. Sporogenes endospore attachment and germination
Authors: Panessa‐Warren Barbara J. , Tortora George T. , Warren John B.
Published: July 2010

The bacterial endospores of C. sporogenes ATCC 3584 are quite small (approximately 0.7–1.0 μm in length) and are difficult to examine during the attachment and germination process by conventional light microscopy methods. Although transmission electron microscopy provides high magnification and resolution, it has not been possible to date to visualize the attachment process and surface changes of intact clostridial endospores. With the advent of higher resolution conventional scanning electron microscopes (SEM), it is now possible to study these small spores attached to their nutrient substrate in their intact state and readily obtain detailed morphologic information about the attachment, germination, and outgrowth process. Spores were examined in their dormant, dehydrated state and allowed to germinate. Samples were prepared for light, transmission, and SEM under anaerobic conditions for morphologic and histochemical examination. SEM revealed that the spores developed a distinct polarity at the beginning of the germination process and that the exosporial membrane at this time produced projections that attached the spore to a substrate. These projections were altered by calcium chelation with EDTA and the presence of barium. Following colchicine and cytochalasin B treatment, the exosporial membrane projections were morphologically altered and the germination sequence was modified. Histochemical examination of the spores suggested that calcium was predominantly located in the protoplast and spore coat.
Imaging of immunolabeled membrane receptors in uncoated sem specimens
Authors: Heinzmann U. , Reininger A. , Autrata R. , Höfler H.
Published: July 2010

Epidermal growth factor receptors (EGFR) were labeled with 10 nm immunogold and examined on uncoated specimens of A431 human epidermoid carcinoma cells. A field emission gun and a high‐sensitivity YAG ring detector were used to demonstrate the affinity labeling simultaneously in the secondary‐electron (SE) and backscattered‐electron (BSE) modes with a low accelerating voltage (Vo). At Vo=2kV, the SE and BSE signals were too weak to identify all markers, while at Vo=3–7 kV labeling was observed unambiguously in both the SE and BSE modes with smaller and higher working distances. Increasing the Vo to above 7 kV sometimes provokes instability of the specimens. A Vo of ⩾ 10 kV produces charging artifacts in the SE image, but permits a BSE image of the gold markers providing additional topographic information. In conclusion, immunogold labeling can be used with good results for uncoated specimens.
Real‐time confocal microscopy of keratocyte activity in wound healing after cryoablation in rabbit corneas
Authors: Chew S. J. , Beuerman R. W. , Kaufman H. E.
Published: July 2010

A modified tandem scanning confocal microscope was used for real‐time in vivo examination of the rabbit cornea following a cryogenic injury. The corneas of New Zealand white rabbits were frozen with a probe that had been cooled by immersion in liquid nitrogen, effectively destroying keratocytes in a central 5 mm diameter zone throughout the total thickness of the cornea. In these eyes, keratocyte repopulation and corneal stromal wound healing proceeded similarly to that which occurs after epikeratophakia, a refractive surgical procedure designed to change the curvature and optical power of the cornea. In epikeratophakia, a cryolathed donor corneal stroma lenticule is sutured onto the bare stroma of the recipient cornea. The collagen tissue lenticule is repopulated by keratocytes (corneal fibroblasts) that migrate in from the host cornea. In our study, the confocal microscope permitted sequential, noninvasive examination of the corneal stroma in the treated animals. Necrosis of the keratocytes, followed by activation of the remaining viable cells in the corneal periphery, was observed in the first 2 to 3 days after cryo injury. A fine stromal fibrous network was seen to develop; in three eyes, this network progressed to the development of a retrocorneal fibrous membrane and dense stromal fibrosis, both of which resulted in significant loss of corneal clarity. Our results suggest that the confocal microscope may be a valuable tool to provide much needed information on wound healing processes at the cellular level after corneal surgery and injury.
In vivo observation of the corneal epithelium
Authors: Tsubota Kazuo
Published: July 2010

Specular microscopy is an important addition to the ophthalmologist's diagnostic armamentarium. Using this technique, it has been found that normal corneal epithelial cells are polygonal, with no abnormal specular reflex. There are no spindle‐shaped, large or small cells, as may be observed in a variety of pathologic conditions. Spindle‐shaped cells are characteristic of the wound‐healing process with cell migration. Large cells were observed not only in wound healing, but also in aphakic diabetic patients, extended‐wear soft contact lens wearers, and individuals with keratoconus. These changes may result from depressed mitosis or inhibited sloughing of superficial cells. Morphometric analysis adds a quantitative dimension to epithelial cell analysis.
The use of confocal microscopy in evaluating corneal wound healing after excimer laser keratectomy
Authors: Essepian John P. , Rajpal Rajesh K. , Azar Dimitri T. , New Kent , Antonacci Robin , Shields William , Stark Walter J.
Published: July 2010

Corneal wound healing following excimer laser keratectomy is the major cause of regression of treatment results. The amount of anterior strorhal haze that develops may be influenced by topical medications. Over a period of 6 months, we followed 15 New Zealand white rabbit eyes that underwent excimer laser keratectomy with the VISX 193‐nm ArF laser at a fluence of 150 mJ/cm2 for a depth of 130 μm. Eyes were randomized to treatment with prednisolone acetate, diclofenac sodium (Voltaren), a combination of both, and a control group. Drops were administered four times a day for 1 week, two times a day for 3 weeks, and the drops were then tapered. All eyes were reepithelialized by 5 to 7 days. The tandem scanning confocal microscope (TSCM) was used to evaluate the corneal wound in vivo weekly for a month and monthly for 6 months. During the early postoperative period, the TSCM revealed significant anterior stromal keratocyte activation with cell elongation and the spindle‐shaped appearance of fibroblasts in all groups. Collagenous stromal scarring was evident initially, then slowly decreased in all treatment groups. This study shows that TSCM is clinically useful for successive in vivo examinations of corneal wounds after excimer laser keratectomy and for comparing the effects of various topical medications.
Limitations in tandem scanning confocal microscopy as a diagnostic tool for microbial keratitis
Authors: Irvine John A. , Ariyasu Reginald
Published: July 2010

One potential application of tandem scanning confocal microscopy is the detection of in vivo pathogens. Our study of an experimental model of Acanthamoeba keratitis demonstrates that while this technology can successfully detect certain organisms, there are currently limitations. These limitations relate to instrument configuration, movement of either the tissue or the microscope, difficulty in reproducibly returning to the area of interest for serial examination, the lack of a distinctive morphology of some pathogens, and limited resolution of the microscope.
Surface plasmon and guided optical wave microscopies
Authors: Aust E. F. , Sawodny M. , Ito S. , Knoll W.
Published: July 2010

This article summarizes some recent developments in the field of surface plasmon and guided optical wave microscopies. It is shown that these imaging techniques based on evanescent light allow for a quantitative optical characterization of ultrathin films with a thickness sensitivity of a few Ångstroms and a lateral resolution of μm.
Evanescent‐field scanning microscope with fourier‐transform infrared spectrometer
Authors: Nakano T. , Kawata S.
Published: July 2010

An evanescent‐field scanning microscope for infrared microanalysis has been developed. This microscope uses an evanescent field produced by total internal reflection with a high refractive index prism to attain a high spatial resolution, better than the wavelength. This microscope was combined with a Fourier‐transform spectrometer. The principle of the method and experimental results for edge detection at different absorption wavelengths are described.
Contact angle analysis on polymethylmethacrylate and commercial wax by using an environmental scanning electron microscope
Authors: Brugnara Marco , Volpe Claudio Della , Siboni Stefano , Zeni Dario
Published: July 2010

The environmental scanning electron microscope (ESEM) represents one of the most exciting breakthroughs in electron microscopy since the invention of the electron microscope. Its ability to observe uncoated and hydrated samples enhances the possibility for investigating the wettability of surfaces at a microscopic level; by varying the relative vapour pressure or the temperature inside the chamber, it is possible to condense water drops on a micron scale. A large problem in measuring contact angles by ESEM is that the observation angle is not parallel or perpendicular to the surface; thus, the study of the droplets profile using the common algorithms such as spherical approximation or axisymmetric drop shape analysis (ADSA) is not possible, because only a spherical cap shape is commonly observed. In this paper we provide a useful mathematical model to calculate the real contact angle from the initial images. Initially, some simulated spherical caps with different contact and observation angles were created by an appropriate graphic package in order to test the mathematical model. Some real drops obtained by ESEM on wax and polymethylmethacrylate (PMMA) were then studied and the results compared with contact angles measured by common methods on the same materials.
Identification of DNA and RNA from retroviruses using ribonuclease A
Authors: Kuznetsov Yuri G. , McPherson Alexander
Published: July 2010

Retroviruses, such as human immunodeficiency virus (HIV), can be disrupted with chemical agents and made to disgorge their encapsidated nucleic acid. The products can be visualized by atomic force microscopy (AFM). Retroviruses may contain both viral genomic RNA and reverse transcribed DNA produced prior to integration into the host cell genome. It is necessary to know which molecules are RNA and which are DNA in order to interpret the events that transpire during infection. DNA, when imaged by AFM, is generally between one and two nanometers in thickness, more regular in its contours, and it is relatively uniform in height over its entire length; RNA, on the other hand, is less than a nanometer in thickness within single stranded regions, but varies dramatically in height over its length due to the presence of secondary structural domains. These observations, however, are often not definitive. Nonetheless, we have been able to tell one from the other using AFM, by exposing the molecules, in buffer, to moderate concentrations of RNase A. Upon exposure to the enzyme, the DNA, which cannot be cleaved, becomes coated with the protein, and the nucleic acid‐protein complex exhibits a height of about three times that of the native molecule, appearing as thick cords. RNA, however, is degraded by the single strand specific RNase A into short, stable, presumably double‐stranded segments, reflecting its pattern of secondary structure. Using this approach, we obtained evidence that reverse transcription of RNA into DNA may occur within the retroviral capsid.