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Numerical predictions of nearshore waves and shoreline runup are usually initialized on the inner shelf, seaward of the surfzone, with sea‐swell (SS) waves from local wave buoys or regional wave models. Lower frequency infragravity (IG) waves are not reliably measured by buoys or included in regional models. Here, co‐located pressure and velocity observations are used to characterize IG waves in 10–15 m depth in southern California. Shoreward propagating IG waves are often dominated by free waves, with the boundwave energy fraction <30% for moderate and low energy incident SS waves. Only 5% of records, with energetic long swell, show primarily bound waves. The shoreline slope of concave beaches increases by ∼3 between spring high and low tides, and free seaward and shoreward IG energy in 10–15 m vary tidally. The observed linear dependency of free IG energy on SS energy and period is consistent with Ardhuin et al. (2014, https://doi.org/10.1016/j.ocemod.2014.02.006)'s parameterization (R2= 0.71). Including the tide level as a proxy for beach slope and modifying the SS frequency dependency increases R2to 0.91. The ratio of free seaward to shoreward propagating IG energy suggests between 50 and 100% of the energy radiated seaward in depths of 10–15 m is trapped offshore and redirected shoreward. Free (random phase) and bound (phase‐coupled) IG waves are combined to initialize the SWASH numerical model. SWASH predicted runup is only weakly influenced by waves at the offshore boundary. Nonlinear IG generation and dissipation in the shoaling and surfzone overwhelm the effects of shoreward propagating waves observed at the offshore boundary. Infragravity (IG) waves are long‐period (25 s–2.5 min) waves that contribute to coastal flooding and beach erosion. IG waves, generated near the shoreline by short‐period sea‐swell (SS) wave groups (known by surfers as “sets”), have long wavelengths (100s of m) and do not typically curl and break like ordinary sea and swell waves. Instead, they can be reflected off the beach face and propagate seaward. Our study concerns IG waves on the inner shelf (10–15 m depth, ∼500–700 m offshore), seaward of the main region of IG generation. Similar to previous observations in Hawai'i and North Carolina, we find most of the reflected, seaward‐going IG energy cannot reach deep water and is trapped on the continental shelf. We develop an observation‐based estimate of IG wave energy on the inner shelf as a function of SS wave energy and tide level. Finally, we show with a numerical model that IG wave runup at the shoreline is influenced only weakly by IG waves on the inner shelf. Infragravity (IG) waves on the inner shelf (10–15 m depth) in San Diego, USA are often dominated by refractively trapped free wavesFree IG energies are parameterized as a function of local sea‐swell conditions and tide levelNumerically modeled wave runup is only weakly influenced by the shoreward propagating IG waves observed at the offshore boundary Infragravity (IG) waves on the inner shelf (10–15 m depth) in San Diego, USA are often dominated by refractively trapped free waves Free IG energies are parameterized as a function of local sea‐swell conditions and tide level Numerically modeled wave runup is only weakly influenced by the shoreward propagating IG waves observed at the offshore boundary

According to the classical Archimedes’ principle, ice floats in water and has a fraction of its volume above the water surface. However, for very small ice particles, other competing forces such as van der Waals forces due to fluctuating charge distributions and ionic forces due to salt ions and charge on the ice surface also contribute to the force balance. The latter crucially depends on both the pH of the water and the salt concentration. We show that a bulge in the air–water interface due to interaction of surface tension with the rising ice particle becomes significant when the particle radius is greater than 50–100 μm. The role of these forces in governing the initial stages of ice condensation has never been considered. Here, we show that small ice particles can only form below an exclusion zone, from 2 nm (in high salt concentrations) up to 1 μm (in pure water at pH 7) thick, under the water surface. This distance is defined by an equilibrium of upward buoyancy forces and repulsive van der Waals forces. Ionic forces due to salt and ice surface charge push this zone further down. Only after growing to a radius larger than 10 μm, will the ice particles eventually float toward the water surface in agreement with the simple intuition based on Archimedes’ principle. Our result is the first prediction of observable repulsive van der Waals forces between ice particles and the water surface outside a laboratory setting. We posit that it has consequences on the biology of ice water as we predict an exclusion zone free of ice particles near the water surface which is sufficient to support the presence of bacteria.

MicroRNAs (miRNAs) are endogenous small ribonucleotides that participate in the orchestration of the genome by regulating target messenger RNA translation. MiRNAs control physiological processes and misexpression of miRNAs is pathogenically involved in many diseases including cardiovascular diseases. Normalization of miRNA expression and thus downstream target networks may have enormous therapeutic chances but also risks. We here highlight and discuss recent advances in the development and use of miRNA therapeutics to target miRNAs in vivothat may translate into novel therapeutic strategies for cardiovascular diseases in the future.

MicroRNAs (miRNAs) are small ribonucleotides regulating gene expression. Circulating miRNAs are remarkably stable in the blood. We tested whether miRNAs are also detectable in urine and may serve as new predictors of outcome in renal transplant patients with acute rejection. We profiled urinary miRNAs of stable transplant patients and transplant patients with acute rejection. The miR‐10a, miR‐10b and miR‐210 were strongly deregulated in urine of the patients with acute rejection. We confirmed these data in urine of a validation cohort of 62 patients with acute rejection, 19 control transplant patients without rejection and 13 stable transplant patients with urinary tract infection by quantitative RT‐PCR. The miR‐10b and miR‐210 were downregulated and miR‐10a upregulated in patients with acute rejection compared to controls. Only miR‐210 differed between patients with acute rejection when compared to stable transplant patients with urinary tract infection or transplant patients before/after rejection. Low miR‐210 levels were associated with higher decline in GFR 1 year after transplantation. Selected miRNAs are strongly altered in urine of the patients with acute renal allograft rejection. The miR‐210 levels identify patients with acute rejection and predict long‐term kidney function. Urinary miR‐210 may thus serve as a novel biomarker of acute kidney rejection.

MicroRNAs (miRNAs) are small ribonucleotides regulating gene expression. Circulating miRNAs are remarkably stable in the blood. We tested whether miRNAs are also detectable in urine and may serve as new predictors of outcome in renal transplant patients with acute rejection. We profiled urinary miRNAs of stable transplant patients and transplant patients with acute rejection. The miR-10a, miR-10b and miR-210 were strongly deregulated in urine of the patients with acute rejection. We confirmed these data in urine of a validation cohort of 62 patients with acute rejection, 19 control transplant patients without rejection and 13 stable transplant patients with urinary tract infection by quantitative RT-PCR. The miR-10b and miR-210 were downregulated and miR-10a upregulated in patients with acute rejection compared to controls. Only miR-210 differed between patients with acute rejection when compared to stable transplant patients with urinary tract infection or transplant patients before/after rejection. Low miR-210 levels were associated with higher decline in GFR 1 year after transplantation. Selected miRNAs are strongly altered in urine of the patients with acute renal allograft rejection. The miR-210 levels identify patients with acute rejection and predict long-term kidney function. Urinary miR-210 may thus serve as a novel biomarker of acute kidney rejection.

Electrochemical reactivity patterns have been established by cyclic voltammetry, EPR, and UV/vis spectroelectrochemistry for the transition [(C6Me6)ClOs]⁺/[(C6Me6)Os] in mononuclear and dinuclear complexes with the 2,2‘-azobispyridine (abpy) and 2,2‘-bipyrimidine (bpym) bridging ligands. The isolated electron reservoir intermediate {[(μ-abpy)[OsCl(C6Me6)]2}^•+ could be analyzed by X band and W band EPR with regard to ¹⁸⁹Os hyperfine splitting and g anisotropy as an abpy anion radical species with significant contribution from the metal centers. The function of the π-conjugated acceptor ligand in mediating the interaction between two equivalent electron and atom transfer sites was analyzed through simulation of the cyclic voltammograms. In comparison with the system bridged by 2,2‘-bipyrimidine, the dinuclear abpy complex displays a much stronger interaction between the two organometallic reaction centers, as illustrated by the 1.14 V vs 0.42 V splitting between the redox potentials separating the two chloride-dissociative processes, i.e., stabilizing the Os⁰Os^II mixed-valent form [(Me6C6)Os(μ-abpy)OsCl(C6Me6)]}⁺. This result parallels the observations made for (C5Me5)Rh- and (C5Me5)Ir-containing analogues and for the coupling of pure electron transfer centers through such bridging ligands.

The quinoline derivatives Os3(CO)n(μm-η²-L-H)(μ-H) (L = quinoline-4-carboxaldehyde, n = 10, m = 2, 4; n = 9, N−C(8) bound, m = 3, 5; n = 10, N−C(2) bound, m = 2, 6; L = quinoline-3-carboxaldehyde, n = 9, N−C(8) bound, m = 3, 7) are obtained by the reaction of Os3(CO)10(CH3CN)2 with the quinoline-3-carboxaldehyde or -4-carboxaldehyde ligand followed by photochemical decarbonylation in the case of 5 and 7. The quinoline-4-carboxaldehyde clusters and the free ligand all show reversible 1e^- reductions, but the electron-deficient 5 shows two separate reversible 1e^- reductions, the first at much less negative potential than for the previously investigated Os3(CO)9(μ3-η²-L-H)(μ-H) (L = phenanthridine, 1; L = 5,6-benzoquinoline, 2), while the free ligand is reduced at a more negative potential than any of the clusters. The spectroscopic properties of the clusters upon electrochemical and chemical reduction have been investigated, and in the case of 4 selective line broadening of its ¹H NMR resonances is observed. Infrared spectrophotoelectrochemistry reveals that the CO stretching modes are shifted to lower frequencies, as expected. The pattern of unpaired spin densities in the reduced clusters predicted from the DFT calculations correlates with the observed selective line broadening, and EPR measurements confirm the formation of the radical anions at g values similar to those observed for pure organic radical anions.

The complex cations [(C5Me5)M(abpy)Cl]⁺ (M = Rh, Ir; abpy = 2,2‘-azobis(pyridine)) are reduced to the coordinatively unsaturated compounds [(C5Me5)M(abpy)] via the EPR and UV/vis spectroelectrochemically detectable radical intermediates [(C5Me5)M^III(abpy^-I)Cl]^•. Fast-scan cyclic voltammetry allowed us to establish the electrochemical potentials. This stepwise mechanism differs from the two-electron processes observed for the analogous systems [(C5Me5)M(N^∧N)Cl]⁺/[(C5Me5)M(N^∧N)] with N^∧N = 2,2‘-bipyridines, bidiazines, 1,4-diaza-1,3-butadienes. In contrast to cobalt systems such as [(C5Me5)Co(bpy)Cl]⁺ the one-electron reduction does not involve the metal. The role of the abpy ligand as an intermediate one-electron storage component for a metal-centered two-electron process is discussed. Further reduction of [(C5Me5)M(abpy)] to [(C5Me5)M^II(abpy^-II)]^- at very negative potentials illustrates the extremely strong π back-donation from the 14-valence-electron fragments (C5Me5)M (M = Rh, Ir).

We report on a family of 19 individuals over four generations in which 12 members are affected with a variant of multiple epiphyseal dysplasia. Beginning in childhood, the disease leads to pain and stiffness of knees, ankles, elbows and finger joints. Some adult patients repeatedly suffer from free articular bodies resulting in locking of the joint. Finally, affected individuals are prone to the development of early degenerative joint disease. Mutation screening of candidate regions revealed a novel point mutation at position −1 in the COL9A2 exon 3/intron 3 splicing region. This G → C substitution most probably induces an alteration of the splicing process. Family screening was carried out by both automated sequencing and by digestion of amplicons with BsaWI. We confirmed the nucleotide substitution in eight clinically affected family members as well as in three presymptomatic young children. Electron microscopy showed that the diameter of collagen fibrils from arthroscopically removed free articular bodies of two patients was not obviously different from that of normal articular cartilage. Together with previous reports our results indicate that mutations leading to skipping of exon 3 within the COL3 domain of the α2-chain of collagen type IX may be relatively common in patients with a special subtype of multiple epiphyseal dysplasia (MED) in which the hips are not markedly affected at early age (EDM2). In these patients and their families, mutation screening of the candidate regions may help to confirm the diagnosis, lead to appropriate advice for lifestyle and well based genetic counseling. © 2002 Wiley-Liss, Inc.

ObjectiveOur aim was to investigate the maintenance of the transfection status of non-viral transfected chondrocytes in an alginate culture system.

The aim of our study was to investigate the influence of four bone substitutes on the growth behavior of a human osteoblastlike cell line SaOS2 culture: pure alpha tricalcium phosphate αTCP BIOBASE®, a bioactive glass bioglass, a neutralized glassceramic GB9N, and solvent dehydrated bone. We established an in vitrocell culture model with threedimensional scaffolds cubes of 0.7 × 0.7 × 1.0 cm of porous bone substitutes to investigate proliferation and differentiation rates of SaOS2 cells. The cultures were analyzed for individual cell morphology after 5 days of growing using scanning electron microscopy. Fracture preparations of the cubes showed that cells could infiltrate the porous structures, but the cell shapes varied from individual roundshaped cells to wide spread cells and cell clusters, depending on the material. Also, the differentiation of the seeded cells was dissimilar after a 5day incubation. The specific alkaline phosphatase ALP enzyme activity ALPDNA measured in the supernatants of αTCPgrown cells was nine times higher than the lowest activity, as observed by cells incubated on GB9N. Early Collagen1, ALP and late marker osteocalcin, bone sialoprotein of osteoblastic differentiation were proofed by reverse transcriptasepolymerase chain reaction analysis. Cells grown on bone substitutes and bioglass seem to be less differentiated than αTCPgrown cells, because of noticeably less amounts of osteocalcin and bone sialoprotein. The cultivation on GB9N seems to dedifferentiate the cells, because even the ALP expression was reduced as well. Our results indicate that distinct bone substitutes influence proliferation and differentiation of osteoblastic cells in different manners. These results might influence the selection of an adequate bone substitute for clinical use as well, part from degradative and biomechanical properties. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 57: 132–139, 2001

Morphological studies of granular neurons of the hippocampus have shown that adrenalectomy (ADX) induces the cell death of granular neurons, an effect prevented by corticosterone replacement. We addressed the hypothesis that corticosterone regulates the expression of the apoptotic bcl-2 gene family. Five days after adrenalectomy, we observed morphological changes related to hippocampal granule cell apoptosis that was accompanied by terminal dUTP nick and labeling (TUNEL) labeling in nuclei located in the hilus region. Corticosterone replacement prevented the cell death induced by ADX. Using RT-PCR we found a reduction in mRNA levels of the antiapoptotic gene bcl-2 in whole hippocampus, an effect which was prevented by corticosterone administration to ADX rats. However, Bcl-2 protein levels were not altered by this treatment. We did not observe modifications in the level of bcl-XLmRNA however, we did find a 40% reduction in Bcl-XLprotein levels, an effect not reversed by corticosterone. In contrast, we found a reduction in the mRNA of the antiapoptotic gene baxand Bax levels after ADX; both effects were prevented by corticosterone. The reduction in proapoptotic baxand in antiapoptotic bcl-2 mRNA levels in the whole hippocampus, suggests that local variations in these molecules could account for both neuronal viability of the CA1-CA3 and granular cell death detected by morphological means and observed after ADX.

The title complex contains two organometallic reaction centers which are known to engage in hydride transfer catalysis (Rh) or in CO2 activation (Re), each after reductive elimination of the respective chloride ligand. The bridged heterodinuclear compound has been structurally characterized in the form where the chloride ligands are in cis-configuration relative to the bptz plane. The complex was subjected to cyclic voltammetry and spectroelectrochemical reduction to reveal an electrochemically reversible one-electron uptake by the bptz bridge, a rhodium chloride-dissociative second reduction to yield neutral [(η⁵-C5Me5)Rh(μ-bptz)Re(CO)3Cl], and a quasi-reversible third one-electron reduction.

We report on the development and current capabilities of the ALOMAR Rayleigh/Mie/Raman lidar. This instrument is one of the core instruments of the international ALOMAR facility, located near Andenes in Norway at 69°N and 16°E. The major task of the instrument is to perform advanced studies of the Arctic middle atmosphere over altitudes between about 15 to 90 km on a climatological basis. These studies address questions about the thermal structure of the Arctic middle atmosphere, the dynamical processes acting therein, and of aerosols in the form of stratospheric background aerosol, polar stratospheric clouds, noctilucent clouds, and injected aerosols of volcanic or anthropogenic origin. Furthermore, the lidar is meant to work together with other remote sensing instruments, both ground- and satellite-based, and with balloon- and rocket-borne instruments performing in situ observations. The instrument is basically a twin lidar, using two independent power lasers and two tiltable receiving telescopes. The power lasers are Nd:YAG lasers emitting at wavelengths 1064, 532, and 355 nm and producing 30 pulses per second each. The power lasers are highly stabilized in both their wavelengths and the directions of their laser beams. The laser beams are emitted into the atmosphere fully coaxial with the line-of-sight of the receiving telescopes. The latter use primary mirrors of 1.8 m diameter and are tiltable within 30° off zenith. Their fields-of-view have 180 µrad angular diameter. Spectral separation, filtering, and detection of the received photons are made on an optical bench which carries, among a multitude of other optical components, three double Fabry-Perot interferometers (two for 532 and one for 355 nm) and one single Fabry-Perot interferometer (for 1064 nm). A number of separate detector channels also allow registration of photons which are produced by rotational-vibrational and rotational Raman scatter on N2 and N2+O2 molecules, respectively. Currently, up to 36 detector channels simultaneously record the photons collected by the telescopes. The internal and external instrument operations are automated so that this very complex instrument can be operated by a single engineer. Currently the lidar is heavily used for measurements of temperature profiles, of cloud particle properties such as their altitude, particle densities and size distributions, and of stratospheric winds. Due to its very effective spectral and spatial filtering, the lidar has unique capabilities to work in full sunlight. Under these conditions it can measure temperatures up to 65 km altitude and determine particle size distributions of overhead noctilucent clouds. Due to its very high mechanical and optical stability, it can also employed efficiently under marginal weather conditions when data on the middle atmosphere can be collected only through small breaks in the tropospheric cloud layers.

More than 250 million of the world's children suffer from vitamin A deficiency. Nepal is one of 60 countries in which this deficiency constitutes a significant public health problem. Each year in Nepal, vitamin A deficiency is responsible for the deaths of 9000 children and for 2500 children becoming permanently blind. The Nepal National Vitamin A Program (NVAP) was begun in 1993 in eight of the country's 75 districts. By the end of 1997, the programme covered 32 districts, and by 2003 its coverage will be nationwide. The Nepal NVAP is considered by many to be a highly successful, model programme. It consists primarily of distributing high-dose vitamin A capsules to all children 6 to 60 months of age during twice-yearly campaigns. The capsule distribution is carried out by a previously existing network of Female Community Health Volunteers (FCHVs) that has been reinvigorated by the highly visible and universally acclaimed success of the NVAP. An important strategy of the programme has been the empowerment of the FCHVs, which has been accomplished by organizing, training and motivating community workers and other representatives from education, agriculture and other sectors, as well as political representatives, to support the FCHVs. The annual cost of the NVAP is US$1.7 million. It costs $1.25 to deliver two vitamin A capsules to each participant. The cost per averted death is $327. The NVAP reduces the incidence and severity of diarrhoeal disease and measles, which in turn reduces the need for Ministry of Health services, thereby annually saving the Government of Nepal $1.5 million. Factoring in these cost savings, the net annual cost of the current NVAP is $167,000, and the net annual cost of the permanent, nationwide programme is estimated at $1.1 million. The NVAP is a highly cost-effective programme. The article concludes with a discussion of the sustainability and replicability of the programme.

Electrochemical reduction of cyclobutadienecyclopentadienylcobalt derivatives, C4R4−Co−C5(HgY)5 [R = C6H5−, Y = −SMe (3), −SCOMe (4), −SCH2CH2SCH3 (5), −SCH2CH2SCOCH3 (6); R = p-EtOCOC6H4−, Y = −SEt (7), −SCOMe (8), −SCH2CH2SCH3 (9), −SCH2CH2SCOCH3 (10)], and the parent C4R4−Co−C5H5 [R = C6H5− (11) and R = p-EtOCOC6H4− (12)] has been examined. Reversible one-electron “metal-centered” reduction of 11 (−2.24 V vs Ag/AgCl) yields a stable radical anion. In 12, it takes place at −1.70 V. In 3−10, similar metal-centered reduction occurs irreversibly, accompanied by an adsorption pre-wave at −0.7 to −1.15 V. We propose that the radical anion loses a −HgSX substituent soon after it is formed. Electrochemical cleavage of the substituents occurs before the metal-centered reduction in 4 and 8 and afterward in the others. The cleaved thiolate fragments yield an anodic peak. In all compounds with ester groups, ester reduction is observed at −2.1 to −2.5 V.

A controlled multiplex polymerase chain reaction (PCR) for the detection ofClostridium(C.)perfringensenterotoxin gene (cpe) was established and compared with anin vitroantigenic detection method. ThecpePCR and the classical method of electric immunodiffusion gave identical results. The predicted specific amplicon of thecpegene was generated from all of the tested enterotoxigenicC. perfringensstrains. In contrast, cultures of any otherClostridiumspecies tested by PCR were negative (100% sensitivity, 100% specificity). Addition of an alphatoxin (plc) gene specific PCR as an in process control reaction was performed in order to prevent false negative PCR results. The PCR detection limit was 0·5 ng of genomicC. perfringensDNA per ml of bouillon culture. By contaminating minced meat withC. perfringensreference strains, the multiplex PCR was established as a tool for routine diagnostic laboratories. The detection limit was approximately 3·0×105C. perfringenscells per gram meat. The results demonstrate the multiplex PCR as an easy, specific, sensitive and time saving diagnostic procedure. Application of this improved method should enhance the knowledge concerning epidemiological aspects of food borne diseases caused by enterotoxigenicC. perfringens.

Determination of 2-oxo-1-pyrrolidine-acetic acid derivatives cannot be carried out either spectroscopically, colorimetrically or fluorimetrically, and GC determination is only conditionally suitable. For the determination of 2-oxo-1-pyrrolidine-acetic acid, its amide, hydrazide as well as 1,2-bis (2-oxo-pyrrolidine-1-acetic acid)-hydrazide and a,?-bis(2-oxo-1-pyrrolidine-acetamido)-alkanes in biological material, a suitable method is the extraction of freeze-dried analytical samples with chloroform/methanol mixtures, TLC on silica gel and detection with various spray reagents. Determinations from whole blood, plasma, organ homogenates and urine are possible by spot area comparison or scanning. The practicability of the method is demonstrated with the example of stability tests in biological material, proof of absorption, and determination of plasma and urine levels in rats, dogs and in man.

Properties of morocromen (solubility, extractability, stability, UV-, fluorescence and TLC-properties) are described. Morocromen can be extracted quantitatively from biological material (blood, organs, bile, saliva, sweat, faeces and urine) with chloroform at pH 8.6. Quantitative determination can be carried out either by UV-spectroscopy (330 nm), or even better by fluorometry: direct determination at 330/440 nm as morocromen or after degradation (4N H2SO4, 100° C) to the more intensely fluorescing 7-amino-derivative (at 309/483 nm) is possible with amounts of <0.01 to 5 µg/ml after previous TLC. The lower detection limit is between 0.02 µg/ml (blood) and 0.008 µg/ml (urine), reproducibility between 0.7% (blood) and 3.0–3.6% (urine). The methods can be used for pharmacokinetic measurements.

After extraction of all F-containing substances (intact substance and the sum of all metabolites) from urine (hydrolysed in alkali under heating) of both man and animals after administration of flufenamic acid and derivatives, the balance of excretion can be determined. After alkaline oxydative degradation (Wurzschmitt bomb) of these extracts and distillation in the presence of sulphuric acid and SiO2 the distillates were investigated colorimetrically at pH 4.35 after addition of an alizarine-3-methylamino-N,N-diacetic-cerium(III) complex. Measurements in the range of =1 µg per sample used are possible. The results obtained for the renal elimination of flufenamic acid and metabolites in man (49.4±4.6%; N=10) are in concordance with the results of other authors who used tracer methods (51%; N=4) and prove the practicability of this method.

Purpose: The impact of radical prostatectomy and external beam radiotherapy on the quality of life of patients was compared. Materials and Methods: A total of 136 patients underwent radical prostatectomy and 60 underwent external beam radiotherapy for clinically localized prostate cancer. Patients were asked to complete a questionnaire containing The Functional Living Index: Cancer, the Profile of Moods States, and a series of questions evaluating bladder, bowel and sexual function. Results: The radical prostatectomy group had worse sexual function and urinary incontinence, while the external beam radiotherapy group had worse bowel function. Of the patients 90 percent from both groups stated that they would undergo the treatment again. Conclusions: Radical prostatectomy and external beam radiotherapy have comparable impact upon quality of life.

The electrochemical behavior of dimetallic [Ni2Cp2](RC&tbd1;CR‘) (Cp = π-cyclopentadienyl; R = R‘ = Ph; COOMe; R = H, R‘ = Ph; R= Me, R‘ = Ph; R = Ph, R‘ = −C&tbd1;CPh) and tetrametallic M2M2‘(PhC&tbd1;CC&tbd1;CPh) (M2 = M2‘ = Ni2Cp2; M2 = Ni2Cp2, M2‘ = Co2(CO)6) derivatives has been investigated. All dinickel compounds undergo an electrochemically and chemically reversible 1e (metal-centered) reduction followed by further ligand-based reductions. The tetrametallic complex [Ni2Cp2]2(PhC&tbd1;CC&tbd1;CPh) shows two fully reversible 1e (metal-centered) reductions, indicating a strong electronic communication between the two redox units (ΔE° = 670 mV). The mixed-metal [Ni2Cp2][Co2(CO)6](PhC&tbd1;CC&tbd1;CPh) derivative exhibits a 1e (Co2-centered) reduction at first, followed by a further 1e (Ni2-centered) reduction; such an electrochemical scenario is complicated by a fast decomposition following the first reduction, which produces some amount of [Ni2Cp2](PhC&tbd1;CC&tbd1;CPh) compound, having a dangling (uncoordinated) triple bond.

Complexes between the 1,4-disubstituted 1,4-diaza-1,3-butadiene chelate ligands RN&dbd;CHCH&dbd;NR (R-DAB; R = alkyl, aryl) and the organoplatinum fragments PtMe2, PtMe4, and PtMes2 (Mes = mesityl) were prepared and characterized with respect to their electronic structures. All compounds are distinguished by low-energy charge-transfer transitions to low-lying π* orbitals of the R-DAB ligands, either from metal d orbitals (Pt^II) or from metal−carbon σ bond combinations (Pt^IV). These spectral assignments are supported by DFT calculations on model complexes between HN&dbd;CHCH&dbd;NH and PtMe2 or PtMe4. The calculations also reproduce the structural results for the complex between CyN&dbd;CHCH&dbd;NCy and PtMe4, which exhibits significantly longer Pt−C bonds to the axial methyl groups. The distinct solvatochromism of the long-wavelength transitions is described, as are the UV/vis spectroelectrochemical results for reversible reduction to Pt^IV(R-DAB^•-) or Pt^II(R-DAB^•-) species (no evidence for a Pt^I state). In contrast, the oxidation is electrochemically irreversible except for the dimesitylplatinum compounds. The electrochemical potentials of corresponding PtMe2 and PtMe4 compounds are very similar, demonstrating that the binding of two additional methyl carbanions compensates for the effect of the higher metal oxidation state. While the organoplatinum(II) species are emissive, the tetramethylplatinum(IV) complexes are photoreactive and undergo metal-to-ligand methyl transfer reactions&sbd;in agreement with the structurally confirmed weaker bonding to the axial methyl groups.

Most Latin American social security institutes are direct providers of medical care services to their beneficiaries. As many of the institutes have developed serious financial problems over the course of the last decade and a half, they have come under increasing attack for (a) exacerbating inequalities in access to and use of health care, (b) further heightening the geographic overconcentration of services, (c) focusing a disproportionate amount of resources on high technology, curative care to the near total exclusion of primary health care, and (d) being administratively top heavy and, more generally, inefficient. In the past few years, many Latin American countries have begun searching for methods to ameliorate these problems. This paper analyzes three recent efforts, all of which involve some degree of privatization: (1) El Salvador's partial privatization of specialty physician outpatient consultations, (2) Peru's minor surgery and its decentralized ambulatory care programme, and (3) Nicaragua's "administrative services only' approach wherein social security beneficiaries choose to join a certified public or private provider organization for one year, and, on behalf of the individual, social security pays the organization a fixed, annual, per capita fee to provide all health care for the enrollee. The paper also identifies political and technical considerations, as well as health care market characteristics that have shaped these efforts and that condition their likelihood of success, including: the size, composition, level of capacity utilization, degree of organization and geographic distribution of private sector resources; relative prices in the private vis-a-vis the public sector; and the size and nature of the private health insurance market. Other Latin American countries would do well to examine these factors and characteristics before embarking on efforts to reform their own social security health care delivery systems.

An increase in exclusive breastfeeding prevalence can substantially reduce mortality and morbidity among infants. In this paper, estimates of the costs and impacts of three breastfeeding promotion programmes, implemented through maternity services in Brazil, Honduras and Mexico, are used to develop cost-effectiveness measures and these are compared with other health interventions. The results show that breastfeeding promotion can be one of the most cost-effective health interventions for preventing cases of diarrhoea, preventing deaths from diarrhoea, and gaining disability-adjusted life years (DALYs). The benefits are substantial over a broad range of programme types. Programmes starting with the removal of formula and medications during delivery are likely to derive a high level of impact per unit of net incremental cost. Cost-effectiveness is lower (but still attractive relative to other interventions) if hospitals already have rooming-in and no bottle-feeds; and the cost-effectiveness improves as programmes become well-established. At an annual cost of about 30 to 40 US cents per birth, programmes starting with formula feeding in nurseries and maternity wards can reduce diarrhoea cases for approximately $0.65 to $1.10 per case prevented, diarrhoea deaths for $100 to $200 per death averted, and reduce the burden of disease for approximately $2 to $4 per DALY. Maternity services that have already eliminated formula can, by investing from $2 to $3 per birth, prevent diarrhoea cases and deaths for $3.50 to $6.75 per case, and $550 to $800 per death respectively, with DALYs gained at $12 to $19 each.

National hospitals in developing countries command a disproportionate share of medical care budgets, justified on the grounds that they have a more difficult patient case mix and higher occupancy rates than decentralized district hospitals or clinics. This paper empirically tests the hypothesis by developing direct measures of the severity of patient illness, hospital case-mix and a resource intensity index for each of El Salvador's public hospitals. Based on an analysis of inpatient care staffing requirements, national hospitals are found to receive funding far in excess of what case-mix and case-load considerations would warrant. The findings suggest that significant system-wide efficiency gains can be realized by allocating hospital budgets on the bases of performance-related criteria which incorporate the case-mix approach developed here.

During a 72 hour fast in pregnant women, significant decrements in the maternal plasma glucose concentrations, accompanied by a significant increase in the plasma placental lactogen (hPL) concentration, occur. At the same time, utilization of glucogenic amino acids, principally alanine, takes place. The mean postprandial glucose concentration in pregnancy is significantly lower than that of comparable nonpregnant women (70.5 ± 1.7 versus 79.5 ± 1.3 mg. per 100 ml., p < 0.001). There appears to be a significant sparing effect on the maternal plasma glucose concentration during acute fasting which may be mediated through hPL. Concentrations of amniotic fluid and fetal plasma glucose from women undergoing fasting decrease in a manner parallel to that of the mother. Fasting provokes a mean rise in plasma hPL of 33.2 per cent over basal levels. This rise is still evident 72 hours after refeeding, after which it gradually returns to pretest concentrations. The infusion of alanine or arginine to pregnant women at the end of the fast produced increments in the peripheral maternal glucose concentration. The response was much greater with alanine than with arginine, demonstrating the increased gluconeogenic potential of this amino acid. The increment in human growth hormone (hGH) following alanine infusion was significantly greater than that observed after arginine administration. Hypoaminoacidemia was present in nonpregnant and pregnant women in response to fasting, but the decline was greater in pregnancy. Acute fasting in the first half of gestation appears to produce significant alterations in carbohydrate metabolism evidenced by profound hypoglycemia, hypoinsulinemia, and hypoaminoacidemia. This maternal deficit can be reflected in fetal substrate concentrations. The effect of these changes on fetal growth and development is speculative at this time.