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Human efforts to produce food and energy are changing the nitrogen (N) cycle of the Earth. Many of these changes are highly beneficial for humans, while others are detrimental to people and the environment. These changes transcend scientific disciplines, geographical boundaries, and political structures. They challenge the creative minds of natural and social scientists, economists, engineers, business leaders, and decision makers. The Second International Nitrogen Conference was designed to facilitate communications among all stakeholders in the “nitrogen community” of the world. The Conference participants’ goal in the years and decades ahead is to encourage every country to make optimal choices about N management in food production and consumption, energy production and use, and environmental protection. Scientific findings and recommendations for decision makers that emerged from the Conference are presented.

Electron transfer across proteins plays an important role in many biological processes, including those relevant for the conversion of solar photons to chemical energy. Previous studies demonstrated the generation of photocurrents upon light irradiation in a number of photoactive proteins, such as photosystem I or bacteriorhodopsin. Here, it is shown that Sn-cytochrome c layers act as reversible and efficient photoelectrochemical switches upon integration into large-area solid-state junctions. Photocurrents are observed both in the Soret band (λ = 405 nm) and in the Q band (λ = 535 nm), with current on/off ratios reaching values of up to 25. The underlying modulation in charge-transfer rate is attributed to a hole-transport channel created by the photoexcitation of the Sn-porphyrin., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The performance of organic electronic devices can be significantly improved by modifying metal electrodes with organic monolayers, which alter the physical and chemical nature of the interface between conductor and semiconductor. In this paper we examine a series of 12 phosphonic acid compounds deposited on the native oxide layer of aluminum (AlOx/Al), an electrode material with widespread applications in organic electronics. This series includes dodecylphosphonic acid as a reference and 11 benzylphosphonic acids, seven of which are fluorinated, including five newly synthesized derivatives. The monolayers are experimentally characterized by contact angle goniometry and by X-ray photoemission spectroscopy (XPS), and work function data obtained by low-intensity XPS are correlated with molecular dipoles obtained from DFT calculations. We find that monolayers are formed with molecular areas ranging from 17.7 to 42.9 Å(2)/molecule, and, by the choice of appropriate terminal groups, the surface energy can be tuned from 23.5 mJ/m(2) to 70.5 mJ/m(2). Depending on the number and position of fluorine substituents on the aromatic rings, a variation in the work function of AlOx/Al substrates over a range of 0.91 eV is achieved, and a renormalization procedure based on molecular density yields a surprising agreement of work function changes with interface dipoles as expected from Helmholtz' equation. The ability to adjust energetics and adhesion at organic semiconductor/AlOx interfaces has immediate applications in devices such as OLEDs, OTFTs, organic solar cells, and printed organic circuits.

The alignment of the electrode Fermi level with the valence or conduction bands of organic semiconductors is a key parameter controlling the efficiency of organic light-emitting diodes, solar cells, and printed circuits. Here, we introduce a class of organic molecules that form highly robust dipole layers, capable of shifting the work function of noble metals (Au and Ag) down to 3.1 eV, that is, ∼1 eV lower than previously reported self-assembled monolayers. The physics behind the considerable interface dipole is elucidated by means of photoemission spectroscopy and density functional theory calculations, and a polymer diode exclusively based on the surface modification of a single electrode in a symmetric, two-terminal Au/poly(3-hexylthiophene)/Au junction is presented. The diode exhibits the remarkable rectification ratio of ∼2·10(3), showing high reproducibility, durability (>3 years), and excellent electrical stability. With this evidence, noble metal electrodes with work function values comparable to that of standard cathode materials used in optoelectronic applications are demonstrated.

Oligoanilines are interesting candidates for organic electronics, as their conductivity can be varied by several orders of magnitude upon protonic doping. Here we demonstrate that tetraaniline self-assembled monolayers exhibit an unprecedented conductance on/off ratio of ∼710 (at +1 V) upon doping of the layers from the emeraldine base to the emeraldine salt form. Furthermore, a pronounced asymmetry in the current-voltage characteristics indicates dynamic doping of the tetraaniline layer by protons generated through field-enhanced dissociation of water molecules, a phenomenon known as the second Wien effect. These results point toward oligoanilines as promising substitutes for polyaniline layers in next-generation thin film devices.

The oriented assembly of molecules on metals is a requirement for rectification in planar metal-molecule-metal junctions. Here, we demonstrate how the difference in adsorption kinetics between dithiocarbamate and thioacetate anchor groups can be utilized to form oriented assemblies of asymmetric molecules that are bound to Au through the dithiocarbamate moiety. The free thioactate group is then used as a ligand to bind Au nanoparticles and to form the desired metal-molecule-metal junction. Besides allowing an asymmetric coupling to the electrodes, the molecules exhibit an asymmetric molecular backbone where the length of the alkyl chains separating the electrodes from a central, para-substituted phenyl ring differs by two methylene units. Throughout the junction fabrication, the layers were characterized by photoelectron spectroscopy, infrared spectroscopy, and scanning tunneling microscopy. Large area junctions using a conducting polymer interlayer between a mercury-drop electrode and the self-assembled monolayer prove the relationship between electrical data and molecular structure.

Nanosecond pulsed electric fields (nsPEFs) eliminates B16f10 melanoma in mice, but cell death mechanisms and kinetics of molecular events of cell death are not fully characterized. Treatment of B16f10 cells in vitro resulted in coordinate increases in active caspases with YO-PRO-1 uptake, calcium mobilization, decreases in mitochondria membrane potential with decreases in forward light scatter (cell size), increases in ADP/ATP ratio, degradation of actin cytoskeleton and membrane blebbing. However, there was no mitochondrial release of cytochrome c, AIF or Smac/DIABLO or generation of reactive oxygen species. Phosphatidylserine externalization was absent and propidium iodide uptake was delayed in small populations of cells. The results indicate that nsPEFs rapidly recruit apoptosis-like mechanisms through the plasma membrane, mimicking the extrinsic apoptosis pathway without mitochondrial amplification yet include activation of initiator and executioner caspases. nsPEFs provide a new cancer therapy that can bypass cancer-associated deregulation of mitochondria-mediated apoptosis in B16f10 melanoma., (Copyright 2010 Elsevier Inc. All rights reserved.)

Cancer continues to be a major risk to the health and well being among populations around the world. A new method using ion-ionizing radiation with nanosecond pulsed electric fields (nsPEFs) provides a novel means to treat cancer at local sites. NsPEFs promote cell death in several cell types and here we investigated mechanisms for cell death induction. In murine B16f10 melanoma, murine E4 squamous carcinoma, murine Hep1-6 and human HepG2 hepatocellular carcinoma, nsPEFs induced cell death in 90-95% of cells. Cell death coincides with decreases in the mitochondria membrane potential, increases in YO-PRO-1 uptake and active caspases in the presence or absence of cytochrome c release. The results indicate that nsPEFs induced cell death by multiple apoptosis mechanisms that involve mitochondrial responses, but not necessarily through cytochrome c release. Further, these in vitro studies suggest a potential to induce cell death that bypasses cancer mechanisms that evade apoptosis.

The structure and electrical properties of self-assembled monolayers of cyclic aromatic and aliphatic dithioacetamides (1,4-bis(mercaptoacetamido)benzene and 1,4-bis(mercaptoacetamido)cyclohexane) and of mixed dithioacetamide/alkanethiol monolayers are characterized by X-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM) and contact angle goniometry. Both dithioacetamides are found to pack densely on Au(111), however the monolayers are poorly ordered as a result of hydrogen bond formation between the amide groups. The coassembly and the insertion method are compared for the formation of mixed dithioacetamide/alkanethiol monolayers. By coassembly, islands of dithioacetamides in a dodecanethiol matrix can only be obtained at a low dithioacetamide/dodecanethiol concentration ratio in solution (1/10) and by thermal annealing of the resulting monolayers. Small and well defined dithioacetamide domains are realized by insertion of dithioacetamides into defect sites of closely packed octanethiol monolayers. These domains are used to determine the molecular conductance by means of STM height profiles and molecular lengths resulting from density functional theory (DFT) calculations. The difference in the tunneling decay constant beta measured for aromatic dithioacetamides (beta = 0.74-0.76/A) and for aliphatic dithioacetamides (beta = 0.84-0.91/A) highlights the influence of the conjugation within the cyclic core on molecular conductance.

Coprecipitation of urea-melt modified carbon nanotubes and calcium carbonate from an aqueous solution by two methods yielded microcrystalline composite particles. Powders obtained by colloidal crystallization from a supersaturated solution that were isolated and dried soon after precipitation were a mixture of raspberry-shaped and rhombohedral particles. These were shown by infrared and X-ray diffraction analyses to be mainly calcite. Particles that were kept wet for 1 day or longer before being isolated were typically entirely rhombohedral with edge lengths in the range of 5-30 microm. Scanning electron microscopy investigations revealed that the nanotubes were adsorbed on the particle surface and also incorporated into the interior matrix. Removal of the calcium carbonate component by treating the particles with acid yielded nanotube shells whose size and shape reflected those of the original particles.

The optical and electrical properties of 11-20 nm thick films composed of approximately 4 nm gold nanoparticles (Au-NPs) interlinked by six organic dithiol or bis-dithiocarbamate derivatives were compared to investigate how these properties depend on the core of the linker molecule (benzene or cyclohexane) and its metal-binding substituents (thiol or dithiocarbamate). Films prepared with the thiol-terminated linker molecules, (1,4-bis(mercaptomethyl)benzene, 1,4-bis(mercaptomethyl)cyclohexane, 1,4-bis(mercaptoacetamido)benzene, and 1,4-bis(mercaptoacetamido)cyclohexane), exhibit thermally activated charge transport. The activation energies lie between 59 and 71 meV. These films show distinct plasmon absorption bands with maxima between 554 and 589 nm. In contrast, the film prepared with 1,4-cyclohexane-bis(dithiocarbamate) has a significantly red-shifted plasmon band ( approximately 626 nm) and a pronounced absorbance in the near infrared. The activation energy for charge transport is only 14 meV. These differences are explained in terms of the formation of a resonant state at the interface due to overlap of the molecular orbital and metal wave function, leading to an apparent increase in NP diameter. The film prepared with 1,4-phenylene-bis(dithiocarbamate) exhibits metallic properties, indicating the full extension of the electron wave function between interlinked NPs. In all cases, the replacement of the benzene ring with a cyclohexane ring in the center of the linker molecule leads to a 1 order of magnitude decrease in conductivity. A linear relationship is obtained when the logarithm of conductivity is plotted as a function of the number of nonconjugated bonds in the linker molecules. This suggests that nonresonant tunneling along the nonconjugated parts of the molecule governs the electron tunneling decay constant (beta(N)(-)(CON)), while the contribution from the conjugated parts of the molecule is weak (corresponding to resonant tunneling). The obtained value for beta(N)(-)(CON) is approximately 1.0 (per non-conjugated bond) and independent of the nanoparticle-binding group. Hence, the molecules can be viewed as consisting of serial connections of electrically insulating (nonconjugated) and conductive (conjugated) parts.

The concept of medical necessity is a provision of commercial insurance contracts and federal government Medicaid requirements that limits the payment to only those services that are essential for treating a person's sickness, injury, or condition. The concept of medical necessity is one tool used by third-party payers to contain their financial risk in a seemingly nonarbitrary manner. Also, the definitions of medical necessity used by commercial insurers or by the federal government reflect their product's or program's philosophies. Expanding commercial insurance or Medicaid psychiatric coverage would require changing those philosophies. As long as society is faced with a greater demand for health-related service than resources to meet them, such systems of rationing will be used. Even with full parity for psychiatric benefits, mechanisms will be used by payers to limit or control demand, thereby controlling financial risk. The short-term challenge for psychiatric advocates is to secure the most acceptable definitions of medical necessity from third-party payers. The long-term challenge for MH/SA advocates and for all health care advocates, is to develop a system that pays for the greatest number of quality services for the greatest number of people in need, in an affordable manner, regardless of diagnosis.

In the 1970s and 1980s, several techniques for assessing the needs for substance user treatment were developed. Generally these techniques relied upon the data developed from large-scale data-gathering systems, originally designed to assess the capacity of the substance user treatment system nationwide. The need assessment techniques generally require making estimates of the prevalence of substance use disorders in the population and then applying them to the national utilitization experience. As first attempts often do, these approaches tended to simplify complex problems and tended to rely too heavily on the only available data. The result was that they tended to reify current practice rather than to define best practice. In the 1990s, new challenges face those attempting to assess needs for substance user services. As a result of the last decade's emphasis on cost containment, new concepts have challenged traditional views of needs assessment. This paper will discuss those new concepts and their impact on the needs assessment endeavor. In particular, the impact of the concept of medical necessity will be examined.

Tris (2,2'-bipyridyl)ruthenium(II)chloride hexahydrate (Ru[bpy]3(2+)) free in solution and adsorbed onto antimony-doped SnO2 colloidal particles was used as a photosensitizer for a comparison of the O2(1 delta g) and electron-transfer-mediated photooxidation of tryptophan (TRP), respectively. Quenching of excited Ru(bpy)3(2+) by O2(3 sigma g-) in an aerated aqueous solution leads only to the formation of O2(1 delta g) (phi delta = 0.18) and this compound was used as a type II photosensitizer. Excitation of Ru(bpy)3(2+) adsorbed onto Sb/SnO2 results in a fast injection of an electron into the conduction band of the semiconductor and accordingly to the formation of Ru(bpy)3(2+) and was used for the sensitization of the electron-transfer-mediated photooxidation. The Ru(bpy)3(3+) is reduced by TRP with a bimolecular rate constant kQ = 5.9 x 10(8) M-1 s-1, while O2(1 delta g) is quenched by TRP with kt = 7.1 x 10(7) M-1 s-1 (chemical + physical quenching). Relative rate constants for the photooxidation of TRP (kc) via both pathways were determined using fluorescence emission spectroscopy. With Np, the rate of photons absorbed, being constant for both pathways we obtained kc = (372/Np) M-1 s-1 for the O2(1 delta g) pathway and kc > or = (25,013/Np) M-1 s-1 for the electron-transfer pathway, respectively. Thus the photooxidation of Trp is more than two orders of magnitude more efficient when it is initiated by electron transfer than when initiated by O2(1 delta g).

A set of anti-melanoma immunoconjugates were prepared which contained chlorin e6: antibody molar ratios of 18.9:1, 11.2:1, 6.8:1, and 1.7:1. All immunoconjugates retained antigen binding activity regardless of the chromophore:antibody substitution ratio that was attained. In contrast, the ground-state absorption spectra of the immunoconjugates showed features which appeared to be dependent on the chromophore:antibody molar ratio. In addition, the quantum yield of singlet oxygen generated by the conjugated chromophores was observed to be significantly less than that observed with the unbound dye. Time-resolved absorbance spectroscopy of the chromophore excited triplet state indicated that the loss of singlet oxygen quantum yield resulted from diminished chromophore triplet yield. Analysis of data obtained from in vitro photolysis of target melanoma cells, in combination with that obtained from the immunochemical and photochemical studies, indicates that the observed immunoconjugate phototoxicity can be reasonably quantitatively represented by (1) the ability of the immunoconjugate to bind SK-MEL-2 cell surface antigen, (2) the amount of chromophore localized at the target cells by immunoconjugate binding, (3) the delivered dose of light at 634 nm, and (4) the singlet oxygen quantum yield of the antibody-bound photosensitizer. Though these data argue strongly for photolysis by the cumulative dosage of singlet oxygen at the cell membrane, nonetheless, the concurrent photoinduced release of other cytotoxic agents should not be ruled out.

In response to the needs both to develop new, nonduplicative alcoholism services and to contain cost, and in order to plan for the labor-intensive alcoholism treatment system, planning techniques are needed to assist in the rational planning for and allocation of manpower. Using data from the 1980 National Drug and Alcoholism Treatment Utilization Survey, it is possible to analyze the staffing patterns of various modalities of alcoholism treatment. Two regression equations were developed to identify key variables for predicting manpower needs in various facilities. Budget, service type, and treatment capacity were statistically significant predictions of direct-care FTE staff in inpatient/residential units. The best predictive ability for direct-care FTE staff in detoxification and longer-term residential facilities was obtained with a general regression model which was based on all types of services (e.g., detoxification, longer-term residential, and outpatient). For outpatient settings, however, direct-care FTE staff was best predicted by considering budgets and treatment capacities within outpatient settings only. Based on this study, a planner can predict, with reasonable confidence, FTE direct-care staff by varying the values of the independent variables in the regression equation to reflect the various characteristics of the services being planned.

Triplet-state properties of 1,4,8,11,15,18,22,25-octa-n-butoxyphthalocyanine and its zinc derivative were determined for the first time. The T1 state of the metal-free phthalocyanine was characterized by a short lifetime (tau T = 17 microseconds) and low quantum yield (phi T = 0.095), and quenching of the triplet by O2 occurred with a bimolecular rate constant (kT sigma = 1.3 x 10(8) M-1 s-1) that is indicative of an endogonic reaction. The zinc complex (ZnPc(OBu)8) was markedly better as a triplet photosensitizer with respect to both tau T (60 microseconds) and phi T (0.5). Quenching by O2 produced singlet oxygen with nearly 100% efficiency, and kT sigma (1.7 x 10(9) M-1s-1) was close to the spin-statistical diffusion-controlled limit. Phosphorescence measurements showed the energy of the T1 state of ZnPc(OBu)8 to be 100 kJ/mol, which is 6 kJ/mol above the 1 delta g state of O2. These photoproperties, together with Q-band absorption maxima in the mid-700 nm range indicate that metal-centered 1,4,8,11,15,18,22,25-octaalkoxyphthalocyanines have excellent potential as sensitizers in photodynamic therapy.

In response to an increasing emphasis on health services planning, a technique for projecting in-residence and outpatient alcoholism treatment and rehabilitation needs has been developed. This technique relies on services data from 34 comprehensive alcoholism treatment programs, funded by the National Institute on Alcohol Abuse and Alcoholism. For in-residence services, the methodology involves an analysis of the use of available in-residence services such that it is possible to determine how many beds of a given service type are needed to serve those admitted to the treatment system. Because all who come in contact with the system do not need or receive services, it is possible to calculate how many beds of a given service type are needed to serve each person coming in contact with the system. This is called the "beds per contact." The product of the beds per contact times the number in the identified target population is the number of beds of a given type needed to serve the target population. A similar methodology is used to project outpatient service needs. The assumptions underlying this technique, and its advantages and disadvantages, are discussed.

In an effort to address the complex realities of mental health service delivery in the 1980s, a systems model for planning and policy making has been developed. The model, called "the Nebraska Mental Health Desired Service System," can serve as a template for future service delivery system design. The development of the model and issues attendant to it are presented. Application of the model to planning, fiscal management, system management, politics, human resources development, and services coordination is presented.

An amphiphilic tris(2,2'-bipyridine)ruthenium(2+) derivative that is incorporated into the walls of phosphatidylcholine vesicles photosensitizes the irreversible oxidation of ethylenediaminetetraacetate(3-) dissolved in the inner aqueous compartments of the vesicle suspension and the one-electron reduction of heptylviologen(2+) dissolved in the continuous aqueous phase. The quantum yield of viologen radical production depends on the phospholipid-to-ruthenium complex mole ratios. A kinetic model is used to derive an order-of-magnitude estimate for the rate constant of electron transport across the vesicle walls. The results are inconsistent with a diffusional mechanism for electron transport and are interpreted in terms of electron exchange.

Several demand-based models for forecasting alcoholism/drug abuse bed needs have been developed over the past few years. Demand models have inherent problems for predicting future needs because of the unknown relationship between the demand group and the nondemand group. Nonetheless, these models hold promise for the alcoholism/drug abuse service system because of some of the unique characteristics of that system. Three models for forecasting alcoholism bed need and one for forecasting drug abuse bed need are discussed; the strengths and weaknesses of each are presented. Projections for the same geographic area are compared. Criteria for selecting one model over another are also recommended.

The photosensitized reduction of heptylviologen in the bulk aqueous phase of phosphatidylcholine vesicles containing EDTA inside and a membrane-bound tris(2,2'-bipyridine)ruthenium(2+) derivative is enhanced by a factor of 6.5 by the addition of valinomycin in the presence of K(+). A 3-fold stimulation by gramicidin and carbonyl cyanide m-chlorophenylhydrazone is observed. The results suggest that, under these conditions, the rate of photoinduced electron transfer across vesicle walls in the absence of ion carriers is limited by cotransport of cations. The rate of electron transfer across vesicle walls could be influenced further by generating transmembrane potentials with K(+) gradients in the presence of valinomycin. When vesicles are made with transmembrane potentials, interior more negative, the quantum yield of heptylviologen reduction is doubled, and, conversely, when vesicles are made with transmembrane potentials, interior more positive, the quantum yield is decreased and approaches the value found in the absence of valinomycin.

In this study, it was hypothesized that community mental health centers (CMHCs) with distinct alcoholism treatment programs (ATPs) would diagnose alcohol problems at a greater frequency than would centers without ATPs. It was also hypothesized that psychoses, personality disorders, and transient situational disturbances would be diagnosed more frequently in CMHCs without ATPs. Yearly diagnostic admission data from nine of Nebraska's CMHCs (four with ATPs, five without) were used. It was found that CMHCs with ATPs diagnosed significantly more alcohol problems than did CMHCs without ATPs (23.5% vs 4.2%). In addition, it was found that CMHCs with ATPs diagnosed significantly lower totals of transient situational disturbances than did CMHCs without ATPs. No differences were found between CMHCs on totals of other diagnostic categories. Practical implications and several alternative explanations for the findings are discussed.

Even when the prevalence of alcohol abuse and alcoholism allows for resource allocation based on differential problem size, further planning methods are necessary in order to determine what specific types of services should be developed to meet the estimated need. Using population-based variables (e.g., total population, White and minority populations) and easily obtainable alcohol indicator variables (consumption, revenue, alcohol-related deaths and arrests), regression models were developed to predict state bed capacity data, obtained from the 1980 National Drug and Alcoholism Treatment Utilization Survey (NDATUS). Prediction models are presented for detoxification, quarterway and halfway house, other residential, hospital, and outpatient. Several variables, particularly total population, deaths, and arrests, are predictive of alcoholism service levels by state, as reflected on NDATUS. Based on this study, estimates of specific service needs within a geographic area can be made by varying the values of the independent variables in the models to reflect the characteristics of the area.