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Accurate description of mineralogy bears on oilfield operations and can be used to calibrate downhole logs and develop petrophysical models for oilfield exploration and development. X-ray diffraction (XRD) is the industry-standard for quantitative mineral analysis, but the accuracy of the method varies substantially due to differences in sample preparation, sample measurement, and data-analysis techniques. This paper reviews the alternative transmission Fourier transform infrared (FTIR) spectroscopy technique for quantitative analysis of sedimentary formations including recent analytical improvements, and examines the differences between XRD and FTIR mineralogy in several case studies. The FTIR procedure has been modified to address two challenges, namely cloudy pellets and the presence of adsorbed water in FTIR spectra. Quantitative mineral analysis by FTIR is enabled using a generalized least-squares inversion against a library of mineral standards with unique IR spectra. Mineralogy results from FTIR are compared with those obtained using XRD techniques commonly practiced by commercial XRD laboratories on over one hundred sedimentary samples spanning carbonate, sandstone and shale lithologies. Accuracy of the mineralogy is evaluated using whole-rock chemistry. Bulk major-element (Si, Ca, Al, K, Na, Mg, Fe, and S) concentrations are reconstructed from the mineralogy by assigning chemical compositions to each mineral, and are then compared against measured elemental concentrations obtained on identical splits of the samples using independent and validated chemical-analysis techniques. Conformance between the reconstructed and measured elemental concentrations is assessed by quantifying the difference between the two. For the sets of samples examined here, FTIR results are consistently better than those from XRD using this conformance criterion. The data indicate that FTIR can provide quantitative and accurate mineral analysis of sedimentary formations, which can be used, for example, to calibrate and validate quantitative petrophysical interpretations in oilfield operations.

To enlarge the donor pool, kidney donors with obesity have been considered. We hypothesized that it is safe for patients with obesity to serve as living kidney donors. In this single-center retrospective analysis, we examined the effect of obesity (body mass index (BMI) of 30–35 kg/m2) on glomerular filtration rate (GFR) and creatinine in patients undergoing laparoscopic donor nephrectomy. Other outcomes included intraoperative, 30-, and 90-day complications. We examined the trajectory between patients with obesity versus patients without obesity over time using mixed effects models for the outcomes of creatinine in mg/dL and GFR in mL/min/1.73 m2. Among donors with obesity versus donors without obesity, there were no significant differences in demographics or comorbidities. Baseline creatinine in donors with obesity was significantly greater than that of donors without obesity (p = 0.02). Operative time was significantly longer in donors with obesity versus without obesity (p = 0.03). There was no significant difference in 30-day morbidity between donors with obesity versus without obesity (6.52 vs. 3.57%, respectively; p = 0.38). The rate of graft complications was 8.7% in donors with obesity versus 7.1% in donors without obesity (p = 1.0). 90-day complications were infrequent, and not significant different between the groups. At 6, 12, and 24-month postoperative follow-up, the mean creatinine level in patients with obesity was not significantly different from that of patients without obesity (1.23 vs. 1.31, 1.23 vs. 1.26, and 1.17 vs. 1.19 at 6, 12, and 24 months, respectively). Mean GFR was also not significantly different at 6, 12, and, 24 months. Postoperative creatinine and GFR changes were not significantly different in patients with obesity versus without obesity after laparoscopic donor nephrectomy. These findings suggest that carefully screened living kidney donors with obesity do not experience decreased postoperative renal function.

The physical and chemical properties of nanocrystals can be modified by changing the ligands attached at their surfaces. A ligand exchange procedure with ammonium polysulfides has been developed to replace the native ligands on cubic zinc sulfide nanocrystals. Several mixtures of polysulfides in formamide and other solvents were prepared with different average chain lengths and used to achieve high yield ligand exchange, as confirmed by UV–vis spectroscopy, infrared spectroscopy and X-ray photoelectron spectroscopy. The results show that polysulfide content can be increased with longer surface ligands and that the exchange process yields compositionally pure surfaces before and after high temperature anneals. X-ray diffraction and scanning electron microscopy show that, when annealed in nitrogen at 525 °C, polysulfide ligands lead to average crystal sizes 2–3 times larger than in the un-exchanged control sample. The ligand exchange procedure itself does not alter nanocrystal size. Nanocrystal inks prepared from the exchanged samples form thin films that exhibit superior grain growth, morphology, mass retention, and composition compared to the un-exchanged material. Overall, polysulfide species are demonstrated as alternative ligands for the surfaces of metal chalcogenide nanocrystals which, when incorporated in an efficient ligand-exchange procedure, can improve the quality of ZnS nanocrystal inks.

The power conversion efficiency of quantum-dot-sensitized solar cells (QDSSCs) hinges on interfacial charge transfer. Increasing quantum dot (QD) loading on the TiO2 anode has been proposed as a means to block recombination of electrons in the TiO2 to the hole transport material; however, it is not known whether a corresponding increase in QD-mediated recombination processes might lead to an overall higher rate of recombination. In this work, a 3-fold increase in PbS QD loading was achieved by the addition of an aqueous base to negatively charge the TiO2 surface during Pb cation deposition. Increased QD loading improved QDSSC device efficiencies through both increased light absorption and an overall reduction in recombination. Unexpectedly, we also found increased QD size had the detrimental effect of increasing recombination. Kinetic modeling of the effect of QD size on interfacial charge transfer processes provided qualitative agreement with the observed variation in recombination lifetimes. These results demonstrate a robust method of improving QD loading, identify the specific mechanisms by which increased QD deposition impacts device performance, and provide a framework for future efforts optimizing the device architecture of QDSSCs.

The abundance of dawsonite in an exploration well in the Green River Formation oil shale has been characterized by well logging, FTIR, DSC, and wet chemistry. The four methods agree qualitatively but not quantitatively. Thermal analysis was then used to characterize changes in the dawsonite decomposition endotherm as a function of pressure. The peak temperature of the endotherm increased with pressure and the size decreased with pressure. The total endotherm at high temperature that includes dolomite and calcite reactions decreased with increased pressure, presumably due to formation of more stable silicates.

In 2015, thirteen per- and polyfluoroalkyl substances (PFAS), including perfluorohexanesulfonate (PFHxS), perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), and perfluorodecanoate (PFDA) were analyzed in human plasma that were collected from a total of 616 American Red Cross male and female blood donors (ages 20-69) at 6 regional blood collection centers. Plasma samples were analyzed using a validated solvent precipitation-isotope dilution direction-liquid chromatography tandem mass spectrometry method. The data were analyzed in conjunction with prior cross-sectional investigations [2000-2001 (n =645), 2006 (n =600), and 2010 (n =600)] to determine PFAS trends. Age- and sex-adjusted geometric mean serum (2000-2001) and plasma (2006, 2010, 2015) concentrations (ng/mL) were, respectively: PFHxS (2.3, 1.5, 1.3, 0.9); PFOS (35.1, 14.5, 8.4, 4.3); PFOA (4.7, 3.4, 2.4, 1.1); PFNA (0.6, 1.0, 0.8, 0.4); and PFDA (0.2, 0.3, 0.3, 0.1). The percentage decline in these geometric mean concentrations from 2000-2001 to 2015 were: PFHxS (61%); PFOS (88%); PFOA (77%); PFNA (33%); and PFDA (50%). The results indicate a continued decline of PFHxS, PFOS, and PFOA concentrations in American Red Cross blood donors. For the remaining PFAS measured in 2015, including the shorter chain perfluoroalkyls perfluorobutanesulfonate (PFBS) and perfluorohexanoate (PFHxA), the majority of samples were below the lower limit of quantitation.

Eleven perfluorinated alkyl acids (PFAAs) were analyzed in plasma from a total of 600 American Red Cross adult blood donors from six locations in 2010. The samples were extracted by protein precipitation and quantified by using liquid chromatography tandem mass spectrometry (HPLC/MS/MS). The anions of the three perfluorosulfonic acids measured were perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS). The anions of the eight perfluorocarboxylic acids were perfluoropentanoate (PFPeA), perfluorohexanoate (PFHxA), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnA), and perfluorododecanoate (PFDoA). Findings were compared to results from different donor samples analyzed at the same locations collected in 2000-2001 (N = 645 serum samples) and 2006 (N = 600 plasma samples). Most measurements in 2010 were less than the lower limit of quantitation for PFBS, PFPeA, PFHxA, and PFDoA. For the remaining analytes, the geometric mean concentrations (ng/mL) in 2000-2001, 2006, and 2010 were, respectively, PFHxS: (2.25, 1.52, 1.34); PFOS (34.9, 14.5, 8.3); PFHpA (0.13, 0.09, 0.05); PFOA (4.70, 3.44, 2.44); PFNA (0.57, 0.97, 0.83); PFDA (0.16, 0.34, 0.27), and PFUnA (0.10, 0.18, 0.14). The percentage decline (parentheses) in geometric mean concentrations from 2000-2001 to 2010 were PFHxS (40%), PFOS (76%), and PFOA (48%). The decline in PFOS suggested a population halving time of 4.3 years. This estimate is comparable to the geometric mean serum elimination half-life of 4.8 years reported in individuals. This similarity supports the conclusion that the dominant PFOS-related exposures to humans in the United States were greatly mitigated during the phase-out period.

The purpose of this study was to determine the concentration trends of a nine-target-analyte homologous series of perfluorocarboxylates from six American Red Cross adult blood donor centers. A total of 645 serum and 600 plasma samples were obtained in 2000-2001 and 2006, respectively, with samples stratified for each 10-year (20-69) age- and sex-group per each location. Samples were extracted by protein precipitation and quantified by using tandem mass spectrometry. The nine perfluorocarboxylates were perfluorobutanoate (PFBA, C(3)F(7)CO(2)(-)), perfluoropentanoate (PFPeA, C(4)F(9)CO(2)(-)), perfluorohexanoate (PFHxA, C(5)F(11)CO(2)(-)), perfluoroheptanoate (PFHpA, C(6)F(13)CO(2)(-)), perfluorooctanoate (PFOA, C(7)F(15)CO(2)(-)), perfluorononanoate (PFNA, C(8)F(17)CO(2)(-)), perfluorodecanoate (PFDA, C(9)F(19)CO(2)(-)), perfluoroundecanoate (PFUnA,C(10)F(21)CO(2)(-)), and perfluorododecanoate (PFDoA, C(11)F(23)CO(2)(-)). The majority of measurements were less than the lower limit of quantitation for PFPeA, PFHxA, and PFDoA. For the remaining targeted analytes, the geometric mean serum and plasma concentrations (ng/mL) for 2000-2001 and 2006 were, respectively, as follows: PFBA 2.61 vs 0.33, PFHpA 0.13 vs 0.09, PFOA 4.70 vs 3.44, PFNA 0.57 vs 0.97, PFDA 0.16 vs 0.34, and PFUnA 0.10 vs 0.18. Estimates of the 95th percent tolerance limits (ng/mL) were as follows: PFBA 5.3 vs 1.4, PFHpA 0.4 vs 0.4, PFOA 12.3 vs 7.7, PFNA 1.4 vs 2.2, PFDA 0.4 vs 0.8, and PFUnA 0.3 vs 0.5. Important observations were the decline in PFBA and increase in PFNA, PFDA, and PFUnA concentrations between 2000-2001 and 2006. The longer chain length perfluorocarboxylates were also highly correlated with each other.

Chemical bath deposition and ion exchange were used to incorporate copper, zinc, tin and sulfur into a thin film precursor stack. The stack was then sulfurized to form the photovoltaic absorber material Cu 2 ZnSnS 4 (CZTS). The morphology and elemental composition of the films at each process stage were analyzed by Auger electron spectroscopy and scanning electron microscopy, and the structural and optical properties of the sulfurized film were determined by a combination of X-ray diffraction, Raman scattering, and diffuse reflectance UV–Vis spectroscopy. Compositionally uniform microcrystalline CZTS with kesterite structure and a bandgap of 1.45 eV were observed. A preliminary solar cell device was produced exhibiting photovoltaic and rectifying behavior.

One integrative measurement of microbial activity in soils is the efficiency by which microbes convert assimilated carbon (C) into biomass C. This efficiency, called the microbial growth efficiency ( Y ), is a key physiological characteristic that regulates soil carbon sequestration, nutrient immobilization, and greenhouse gas emissions. Changes in rainfall patterns and soil water content as the result of global climate change have the potential to influence microbial activity and lead to changes in Y and thus, nutrient cycling at the ecosystem level. Unfortunately, little information is available on how environmental variables such as soil moisture influence Y . We have developed a new method for injecting 13 C-labeled carbon as acetic acid vapor into soil that will allow measurement of microbial growth efficiency (as Y C ) without increasing soil moisture content. We compare Y determined with this new approach with an alternate method where injected 15 N-labeled ammonia gas is used to quantify microbial N immobilization, and microbial growth efficiency is calculated based on microbial C:N and respiration rate (as Y N ). We also include injections of a solution containing labeled ammonium and acetate in our experiment to compare the results of our vapor methods with more commonly employed liquid-based methods. The 13 C-acetic acid vapor, which was supplied to soils with soil moisture content ranging from 0.05 to 0.21 g H 2 O g −1 soil, was readily assimilated and respired by microbes. Between 0.10 and 0.21 g H 2 O g −1 soil (−0.60 to −0.04 MPa), values of Y C averaged 0.46, and were significantly lower than values of Y N , with average values of 0.58. Over this range, soil moisture content had no significant effect on either Y C or Y N . However, at the lowest soil moisture content (0.05 g H 2 O g −1 soil; Y C and Y N diverged substantially, suggesting that in very dry soils, constraints on microbial growth cause differential uptake of C and N resources.

To test the hypothesis that an acute increase in O(2) tension increases cytosolic calcium ([Ca(2+)](i)) in fetal pulmonary artery endothelial cells (PAECs) via entry of extracellular calcium and subsequent calcium-induced calcium release (CICR) and nitric oxide release, low-passage PAECs (

At birth, the lung environment changes from low to relatively high O2tension. Pulmonary blood flow increases and pulmonary artery pressure decreases. Recent data suggest that pulmonary vascular calcium-sensitive K+channel (BKCa) activation mediates perinatal pulmonary vasodilation. Although BKCachannel expression is developmentally regulated, the molecular mechanisms responsible for BKCaexpression remain unknown. We tested the hypothesis that the low-O2tension environment of the normal fetus modulates BKCachannel expression. We analyzed BKCaexpression under conditions of hypoxia and normoxia both in vitro and in vivo. BKCaα-subunit mRNA expression increased twofold in ovine pulmonary artery smooth muscle cell (PASMC) primary cultures maintained in hypoxia. In vivo, BKCaexpression was similarly affected by hypoxia. When adult Sprague-Dawley rats were placed in hypobaric hypoxic chambers for 3 wk, hypoxic animals showed an increase of threefold in the expression of BKCaα- and more than twofold in the expression of BKCaβ1-subunit mRNA. Immunochemical staining was consistent with the genetic data. To assess transcriptional activation of the β-subunit of the BKCa, both BKCaβ1- and β2-subunit luciferase (KCaβ:luc+) reporter genes were constructed. Hypoxia increased PASMC KCaβ1:luc+reporter expression by threefold and KCaβ2:luc+expression by 35%. Fetal PASMC treated with the hypoxia-inducible factor-1 mimetic deferoxamine showed a 63 and 41% increase in BKCachannel α- and β1-subunit expression, respectively. Together, these results suggest that oxygen tension modulates BKCachannel subunit mRNA expression, and the regulation is, at least in part, at the transcriptional level.

Perfluorooctanesulfonyl fluoride-based products have included surfactants, paper and packaging treatments, and surface protectants (e.g., for carpet, upholstery, textile). Depending on the specific functional derivatization or degree of polymerization, such products may degrade or metabolize, to an undetermined degree, to perfluorooctanesulfonate (PFOS), a stable and persistent end product that has the potential to bioaccumulate. In this investigation, a total of 645 adult donor serum samples from six American Red Cross blood collection centers were analyzed for PFOS and six other fluorochemicals using HPLC-electrospray tandem mass spectrometry. PFOS concentrations ranged from the lower limit of quantitation of 4.1 ppb to 1656.0 ppb with a geometric mean of 34.9 ppb [95% confidence interval (CI), 33.3-36.5]. The geometric mean was higher among males (37.8 ppb; 95% CI, 35.5-40.3) than among females (31.3 ppb; 95% CI, 30.0-34.3). No substantial difference was observed with age. The estimate of the 95% tolerance limit of PFOS was 88.5 ppb (upper limit of 95% CI, 100.0 ppb). The measures of central tendency for the other fluorochemicals (N-ethyl perfluorooctanesulfonamidoacetate, N-methyl perfluorooctanesulfonamidoacetate, perfluorooctanesulfonamidoacetate, perfluorooctanesulfonamide, perfluorooctanoate, and perfluorohexanesulfonate) were approximately an order of magnitude lower than PFOS. Because serum PFOS concentrations correlate with cumulative human exposure, this information can be useful for risk characterization.

A tandem reduction-reductive amination reaction has been applied to the synthesis of 3,4-dihydro-2H-1,4-benzoxazines and 1-acetyl-1,2,3,4-tetrahydroquinoxalines. The nitroketones required for the benzoxazine ring closures were prepared by (A) alkylation of the anion derived from 2-nitrophenol with an allylic halide or (B) nucleophilic aromatic substitution of an allylic alkoxide on 2-fluoro-1-nitrobenzene followed by ozonolysis. Precursors for the quinoxalines were prepared by alkylation of the anion of 2-nitroacetanilide with an allylic halide followed by ozonolysis. Catalytic hydrogenation of the nitroketones using 5% palladium-on-carbon in methanol then gave the target heterocycles by a reduction-reductive amination sequence. The N-methyl derivatives for both ring systems were easily prepared by adding 5-10 equivalents of aqueous formaldehyde prior to the reduction. The dihydrobenzoxazines were isolated in high yield following purification by chromatographic methods; tetrahydroquinoxalines were isolated in a similar manner and possessed differentiated functionality on the two nitrogens.

N-Phenyl-substituted pyrrolidines and piperidines have been synthesized by catalytic reduction of nitrobenzene in the presence of 4- and 5-oxoaldehydes, respectively. The process involves reduction of the aromatic nitro group to give the N-phenylhydroxylamine or aniline followed by reductive amination with the two carbonyl functional groups. Monocyclic systems are generally formed in high yield and are easily purified. The method has also been extended to the synthesis of fused N-phenylazabicyclics from 2-(3-oxo-propyl)cycloalkanones. A high degree of diastereoselectivity for the trans-fused product is observed in substrates having an ester group α to the cycloalkanone carbonyl. Bicyclic precursors lacking this ester group give mixtures of cis and trans products. Finally, contrary to previous reports, we have demonstrated that aniline can be substituted for nitrobenzene in these reactions.

The Knoevenagel reaction of benzaldehyde and several chloroderivatives with methyl cyanoacetate catalyzed by K2NiP2O7 leads to methyl (E)-α-cyanocinnamate derivatives in 40 min with yields of 71.65–83.45%. Pure products are easily obtained in crystalline form, uncontaminated by side products or by stereoisomers. Methyl 2-chlorocyanocinnamate, methyl 2,4-dichlorocyanocinnamate, and a new polymorph of methyl cyanocinnamate have been characterized by single crystal X-ray diffraction.

K+channels play an important role in mediating pulmonary vasodilation caused by increased oxygen tension, nitric oxide, alkalosis, and shear stress. To test the hypothesis that lung K+ channel gene expression may be altered by chronic increases in pulmonary blood flow, we measured gene and protein expression of calcium-sensitive (KCa) and voltage-gated (Kv2.1) K+ channels, and a pH-sensitive K+channel (TASK), in distal lung from fetal lambs in which an aortopulmonary shunt was placed at 139 days gestation. Under baseline conditions, animals with an aortopulmonary shunt showed elevated pulmonary artery pressure and pulmonary blood flow compared with twin controls. Hypoxia caused a greater increase in pulmonary vascular tone in shunt animals compared with controls. Alkalosis caused pulmonary vasodilation in control but not shunt animals. To determine lung K+ channel mRNA levels, we performed quantitative RT-PCR. In comparison with control animals, lung KCa channel mRNA content was increased in shunt animals, whereas TASK mRNA levels were decreased. There was no difference in Kv2.1 mRNA levels. Channel protein expression was consistent with these findings. We conclude that, in the presence of elevated pulmonary blood flow, KCachannel expression is increased and TASK is decreased.

Objective: This study was performed to assess the electrocardiographic safety and pharmacokinetics of desloratadine in combination with the CYP3A4 inhibitor ketoconazole. Design: A randomised, placebo-controlled, third-party—blind, 2-way crossover study. Participants: 24 healthy volunteers (12 men, 12 women; age 19 to 50 years). Interventions: 7.5mg of desloratadine orally per day in combination with placebo or with 200mg of ketoconazole every 12 hours for 10 days. After a minimum 7-day washout period, participants received the alternative treatment. Main outcome measures: ECG parameters. Results: Comparable maximum corrected QT (QTc) intervals were observed after coadministration of desloratadine and placebo or ketoconazole (431 and 435 msec, respectively). The desloratadine/ketoconazole combination did not induce any statistically significant or clinically relevant changes in QTc, QT, PR or QRS intervals compared with desloratadine alone; ventricular rate was slightly slower when desloratadine was given with ketoconazole. At steady state, coadministration of ketoconazole resulted in no significant change in area under the desloratadine concentration-time curve (AUC) from 0 to 24 hours compared with desloratadine/placebo. Coadministration of desloratadine and ketoconazole resulted in a 1.3-fold increase in desloratadine maximum concentration (Cmax) that was not clinically relevant. The most common adverse event was headache, reported in 42 and 38% of individuals, respectively, after coadministration of desloratadine/placebo and desloratadine/ketoconazole. There were no reports of dizziness or syncope. Conclusion: Coadministration of desloratadine and ketoconazole was well tolerated and was associated with minimal increase in AUC and Cmax. The combination did not induce any clinically relevant electrocardiographic changes.

A diastereoselective synthesis of 1-methyl-2-alkyl- and 2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylic esters has been developed from methyl (2-nitrophenyl)acetate (1). The method involves alkylation of 1 with an allylic halide, ozonolysis of the double bond, and catalytic hydrogenation. The final hydrogenation initiates a tandem sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the aniline or hydroxylamine(8) nitrogen with the side chain carbonyl, (3) reduction of the resulting nitrogen intermediate, and (4) reductive amination of the tetrahydroquinoline with formaldehyde produced in the ozonolysis to give a methyl (+/-)-1-methyl-2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylate. Removal of the formaldehyde prior to hydrogenation gives the simple (+/-)-2-alkyl derivatives. The products are isolated in high yield as single diastereomers having the C-2 alkyl group cis to the C-4 carboxylic ester. The reaction has been extended to the synthesis of tricyclic structures with similar high diastereoselection.

The dose proportionality of lubeluzole, a drug in clinical development for the treatment of acute ischemic stroke, was evaluated in a Phase I, single-center, open-label, randomized-dosing-sequence, three-way crossover clinical trial in 12 healthy adults. An equal number of male and female volunteers were enrolled in the trial, with a mean weight (+/- SD) of 73.2 +/- 11.9 kg, mean height (+/- SD) of 66.8 +/- 4.6 inches, and a mean age of 36.1 +/- 5.2 years. Subjects received intravenous infusions of 5 (A), 10 (B), and 15 mg (C) of lubeluzole over 1 hour on three separate occasions, with a minimum washout period of 2 weeks. The treatment sequences were A-B-C; A-C-B; B-A-C; B-C-A; C-A-B; and C-B-A. One male and one female were assigned to each sequence. After the 5-, 10-, and 15-mg doses, maximum concentration (Cmax) was 58.1, 113, and 138 microg/L, respectively, and the area under the curve from 0 to (AUC(0-infinity)) was 771, 1384, and 2025 microg x h/L. There were no statistically significant differences among the groups in mean terminal half-life, steady-state volume of distribution, total plasma clearance, or dose-normalized AUC(0-infinity). Dose-normalized values of Cmax differed significantly between the groups. No serious adverse events were reported, and no changes were observed in cardiac function, as judged by the QT(c) interval. The pharmacokinetics of lubeluzole appear to be linear at intravenous infusion doses of 5, 10, and 15 mg, and these doses are well tolerated by healthy adults.

Summary Discovered in 1955, the Lower Lagunillas member reservoir of the Miocene Lagunillas formation of Bloques III and IV of the Bachaquero field was originally estimated to contain 2 billion barrels of oil. This reservoir interval traditionally has been interpreted to have been deposited in a delta plain setting and to comprise three reservoir subdivisions that were developed as a single drainage unit. Field performance, however, has indicated that the reservoir is more complex; the present study was initiated to provide a revised development strategy. Sedimentological interpretation of four cored wells has led to the development of a new model of deposition in tidally influenced lower delta plain and delta-front settings. This model is supported by Fourier transform infrared (FT-IR) measurement of clay concentrations and prompt neutron capture boron measurements that are indicative of a brackish water-depositional setting. We used this geological model to guide correlation of wireline logs from 46 wells in the central part of Bloque IV and to provide a high-resolution sequence stratigraphic model of the Lower Lagunillas reservoir. Eleven genetic layers are identified that are separated by locally developed intraformational seals into up to eight drainage units. High permeability, tidally influenced channel-fill sands have acted as preferential conduits for gas influx, leaving bypassed oil in lower quality sands that were deposited as tidal deltas and bars. This reservoir model has been supported by re-examination of production data and by openhole measurements in a recent infill well and cased- hole logging of two other wells in the study area. The new model will form the basis for redevelopment of the Lower Lagunillas reservoir to increase recovery further from this mature field.

In cystic fibrosis the bronchiectatic conducting airways have large numbers of neutrophils in their walls and in their luminal contents. The neutrophil's primary granule enzyme activities of elastase and peroxidase are increased in the sputum of these patients. It has been postulated that these enzymes--together or individually--act to damage the airway epithelium. However, only peroxidase activity has consistently correlated with the degree of structural and functional airway disease in these patients with leakage of plasma protein into the airway lumen (Regelmann et al., Pediatr Pulmonol, 1995; 19:1-9). The present study was designed to test whether human neutrophil-derived myeloperoxidase can independently produce bronchial epithelial damage without the presence of proteases, as measured by increased permeability of the airway epithelium. Human peripheral blood neutrophils were purified, their primary granules isolated, and their peroxidase purified using affinity and ion exchange column chromatography. Activity of the proteinase-free peroxidase was measured using a chromogenic substrate. The effect of this peroxidase on the permeability of excised rat tracheas was measured using radioactive and fluorescent-labeled non-ionic molecules of varying molecular weight. Rat tracheas exposed to 15 minute treatments with either 130 U of peroxidase or hydrogen peroxide (10(-5) M) did not show a significant increase in the permeability of the epithelium to [3H]inulin, [14C]sucrose, and fluorescein isothiocyanate dextran 20 compared with control tracheas. However, those tracheas exposed to 130 U peroxidase followed by 10(-5) M hydrogen peroxide showed an increased permeability to each of the three test solutes. We conclude that proteinase-free myeloperoxidase, in the presence of non-toxic concentrations of its substrates, hydrogen peroxide and halide, produced increases in permeability to non-ionic molecules in the rat trachea within 15 minutes.

Historically, well logging and interpretation workflows have been developed mainly for use in porous and permeable reservoir formations and are not commonly used to evaluate source rocks or unconventional reservoirs. Instead, the evaluation of source rocks, such as the organic-rich deposits of the Green River Formation, has relied primarily on expensive and inefficient core analyses such as the Fischer Assay and simple log interpretation. With the potential oil equivalent in place exceeding a trillion barrels, there is a need for detailed characterization of these oil shale deposits using high resolution well logs. We have logged two Green River wells using combinations of standard and advanced logging techniques. This program was supported by extensive core analysis, including Fischer assay and thorough mineralogical and chemical analyses. Methods of determining kerogen content from log responses were developed along with multiple methods of estimating a continuous log of formation water salinity. We developed methods for quantitatively evaluating these Green River oil shales by integrating standard logs with more advanced logging measurements including nuclear magnetic resonance, elemental capture and inelastic spectroscopy, and dielectric dispersion. The results and the petrophysically derived multi-mineral model are validated by the core measurements and then applied to a near-by well.

Tin (II) sulfide is prepared through chemical bath deposition and annealed in a hydrogen sulfide environment to produce thin films for photovoltaic devices. The grain size, composition, and morphology are controlled by tailoring the bath composition and annealing conditions. The films have stoichiometric composition, are oxygen-free, have an optical band gap below 1.2 eV, and have an orthorhombic crystal structure. Through this method, a variety of film morphologies can be deposited, from dense films to micro-crystalline porous materials, in which micro-structured platelets can be incorporated through a self-assembly process. Annealing treatments simultaneously increase crystal size and improve purity to more efficiently extract photo-generated carriers. Electronic properties of the films are presented as well as insights into device preparation.

Thin films of Cu 2 ZnSnS 4 (CZTS) were fabricated through a combination of chemical bath deposition, ion exchange and sulfurization heat treatment. Scanning electron microscopy was used to study the morphology of the thin films, Auger electron spectroscopy for compositional analysis, X-ray diffraction and Raman scattering for structural characterization, and diffuse reflectance UV-Vis measurements for optical properties. With the method described, compositionally uniform microcrystalline CZTS with kesterite structure and a bandgap of 1.45 eV have been produced, and a preliminary solar cell device was fabricated to demonstrate that this material is applicable in earth-abundant, non-toxic thin film photovoltaics.

A diastereoselective synthesis of 1-methyl-2-alkyl- and 2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylic esters has been developed from methyl (2-nitrophenyl)acetate (1). The method involves alkylation of 1 with an allylic halide, ozonolysis of the double bond, and catalytic hydrogenation. The final hydrogenation initiates a tandem sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the aniline or hydroxylamine8 nitrogen with the side chain carbonyl, (3) reduction of the resulting nitrogen intermediate, and (4) reductive amination of the tetrahydroquinoline with formaldehyde produced in the ozonolysis to give a methyl (±)-1-methyl-2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylate. Removal of the formaldehyde prior to hydrogenation gives the simple (±)-2-alkyl derivatives. The products are isolated in high yield as single diastereomers having the C-2 alkyl group cis to the C-4 carboxylic ester. The reaction has been extended to the synthesis of tricyclic structures with simila...

Tens of millions of people in Southeast Asia drink groundwater contaminated with naturally occurring arsenic. How arsenic is released from the sediment into the water remains poorly understood. Here, we show in laboratory experiments that phosphate-limited cells of Burkholderia fungorum mobilize ancillary arsenic from apatite. We hypothesize that arsenic mobilization is a by-product of mineral weathering for nutrient acquisition. The released arsenic does not undergo a redox transformation but appears to be solubilized from the apatite mineral lattice during weathering. Analysis of apatite from the source area in the Himalayan basin indicates the presence of elevated levels of arsenic, with an average concentration of 210 mg/kg. The rate of arsenic release is independent of the initial dissolved arsenic concentration and occurs at phosphate levels observed in Bangladesh aquifers. We also demonstrate the presence of the microbial phenotype that releases arsenic from apatite in Bangladesh aquifer sediments and groundwater. These results suggest that microbial mineral weathering for nutrient acquisition could be an important mechanism for arsenic mobilization.

Freshly isolated monocytes from cystic fibrosis (CF) heterozygotes and homozygotes had significantly increased oxygen uptake and superoxide formation after surface glycoprotein stimulation than did monocytes from age- and sex-matched controls. Lack of differences among the genotypes in inhibition by simple sugars of the concanavalin A-stimulated superoxide production and lack of differences in concanavalin A-binding surface proteins suggested that different regulation of the oxidase pathway produced the increased oxygen uptake and superoxide formation in CF patients and carriers. This regulatory role is consistent with the predicted structure of the CF gene product. The results support the hypothesis that the mononuclear phagocytes of CF heterozygotes have a significantly increased ability to kill intracellular microbes and may confer a selective advantage to the host.

Oxygen causes perinatal pulmonary dilatation. Although fetal pulmonary artery smooth muscle cells (PA SMC) normally respond to an acute increase in oxygen (O2) tension with a decrease in cytosolic calcium ([Ca2+]i), an acute increase in O2 tension has no net effect on [Ca2+]i in PA SMC derived from lambs with chronic intrauterine pulmonary hypertension (PHTN). The present experimental series tests the hypothesis that an acute increase in O2 tension decreases capacitative calcium entry (CCE) in normal, but not hypertensive, fetal PA SMC. PA SMC were isolated from late-gestation fetal lambs after either ligation of the ductus arteriosus (PHTN) or sham (control) operation at 127 days gestation. PA SMC were isolated from the distal PA (≥4th generation) and maintained under hypoxic conditions (∼25 Torr) in primary culture. After fura 2 loading, apparent [Ca2+]i in PA SMC was determined as the ratio of 340- to 380-nm fluorescence intensity. Under both hypoxic and normoxic conditions, cyclopiazonic acid (CPA) increased [Ca2+]i more in PHTN than in control PA SMC. CCE was determined in PA SMC under hypoxic and normoxic conditions, after superfusion with zero extracellular Ca2+ and intracellular store depletion with CPA, followed by superfusion with Ca2+-containing solution, in the presence of the voltage-operated calcium channel blockade. CCE was increased in PHTN compared with control PA SMC under conditions of both acute and sustained normoxia. Transient receptor potential channel gene expression was greater in control compared with PHTN PA SMC. PHTN may compromise perinatal pulmonary vasodilation, in part, by modulating PA SMC CCE.

Deficiencies in vitamins and other nutrients are common following the Roux-en-Y gastric bypass (RYGBP), biliopancreatic diversion (BPD) and biliopancreatic diversion with duodenal switch (BPDDS), and may become clinically significant if not recognized and treated with supplementation. This paper presents a review of the current literature and evidence of the most commonly deficient vitamins and minerals following weight loss surgery, including protein, iron, vitamin B12, folate, calcium, the fat-soluble vitamins (A, D, E, K), and other micronutrients. The deficiencies appear to be more substantial following malabsorptive procedures such as BPD, but occur with restrictive procedures as well. The review suggests that further studies are needed to evaluate the clinical significance of the nutritional deficiencies, and to determine guidelines for supplementation.

In utero, blood shunts away from the lungs via the ductus arteriosus (DA) and the foramen ovale. After birth, the DA closes concomitant with increased oxygen tension. The present experimental series tests the hypothesis that oxygen directly increases DA smooth muscle cell (SMC) cytosolic calcium ([Ca2+]i) through inactivation of a K+channel, membrane depolarization, and entry of extracellular calcium. To test the hypothesis, DA SMC were isolated from late-gestation fetal lambs and grown to subconfluence in primary culture in low oxygen tension (25 Torr). DA SMC were loaded with the calcium-sensitive fluorophore fura-2 under low oxygen tension conditions and studied using microfluorimetry while oxygen tension was acutely increased (120 Torr). An acute increase in oxygen tension progressively increased DA SMC [Ca2+]iby 11.7 ± 1.4% over 40 min. The effect of acute normoxia on DA SMC [Ca2+]iwas mimicked by pharmacological blockade of the voltage-sensitive K+channel. Neither removal of extracellular calcium nor voltage-operated calcium channel blockade prevented the initial increase in DA SMC [Ca2+]i. Manganese quenching experiments demonstrated that acute normoxia initially decreases the rate of extracellular calcium entry. Pharmacological blockade of inositol triphosphate-sensitive, but not ryanodine-sensitive, intracellular calcium stores prevented the oxygen-induced increase in [Ca2+]i. Endothelin increased [Ca2+]iin acutely normoxic, but not hypoxic, DA SMC. Thus acute normoxia 1) increases DA SMC [Ca2+]ivia release of calcium from intracellular calcium stores, and subsequent entry of extracellular calcium, and 2) potentiates the effect of contractile agonists. Prolonged patency of the DA may result from disordered intracellular calcium homeostasis.

N-Phenyl-substituted pyrrolidines and piperidines have been synthesized by catalytic reduction of nitrobenzene in the presence of 4- and 5-oxoaldehydes, respectively. The process involves reduction of the aromatic nitro group to give the N-phenylhydroxylamine or aniline followed by reductive amination with the two carbonyl functional groups. Monocyclic systems are generally formed in high yield and are easily purified. The method has also been extended to the synthesis of fused N-phenylazabicyclics from 2-(3-oxo-propyl)cycloalkanones. A high degree of diastereoselectivity for the trans-fused product is observed in substrates having an ester group α to the cycloalkanone carbonyl. Bicyclic precursors lacking this ester group give mixtures of cis and trans products. Finally, contrary to previous reports, we have demonstrated that aniline can be substituted for nitrobenzene in these reactions.

A two-step diastereoselective synthesis of linear-fused tricyclic nitrogen heterocycles has been developed from cyclic β-ketoesters. The cyclization substrates are readily prepared by alkylation of the methyl 2-oxo-cycloalkanecarboxylates with 2-nitrobenzyl bromide. Hydrogenation of these substrates initiates a reaction sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the resulting hydroxyl-amine or aniline nitrogen with the cycloalkanone and (3) reduction of the imine. The products are isolated in high yield as single diastereomers having the trans-fused ring junction. The observed selectivity is rationalized in terms of a steric effect imposed by the ester group in the final reductive amination step which directs the incoming hydrogen to the opposite face of the molecule. By comparison, reductive cyclizations of substrates lacking the stereodirecting ester group give mixtures of cis and trans products with a preference for the cis-fused heterocycle.

The SnS absorber layer in solar cell devices was produced by vapor transport deposition (VTD), which is a low-cost manufacturing method for solar modules. The performance of solar cells consisting of Si/Mo/SnS/ZnO/indium tin oxide (ITO) was limited by the SnS layer's surface texture and field-dependent carrier collection. For improved performance, a fluorine doped tin oxide (FTO) substrate was used in place of the Mo to smooth the topography of the VTD SnS and to make bifacial solar cells, which are potentially useful for multijunction applications. A bifacial SnS solar cell consisting of glass/FTO/SnS/CdS/ZnO/ITO demonstrated front- and back-side power conversion efficiencies of 1.2% and 0.2%, respectively.

Carbonate rocks are diverse, and their pore space complex. Petrophysical evaluation of carbonates with techniques developed for siliciclastic environments often fall short. In this paper, we present a new methodology that combines diverse texture and facies sensitive measurements. The method parametrizes the pore structure in terms of a multiporosity system of fractures, vugs, inter- and intra-granular porosities, and evaluates the parameters from the measurements. The process is based on physics and relies minimally on empirical correlations. The first step is to separate the fracture from the matrix using borehole images and then quantify mineral volumes and porosity through nuclear magnetic resonance (NMR) and/or nuclear logs with new mineral standards. Next, we classify the lithology with a self-organizing-map (SOM) algorithm using a vector of log-inputs. Following this, the vug fraction is estimated using shear modulus data and borehole image analysis. Finally, we separate the inter- and intragranular components using NMR data. This analysis includes molecular diffusion between different pore types. The NMR processing scheme also depends on lithology. The porosity components and the relevant length scales enable us to predict resistivity and permeability using an effective medium theory in an internally consistent manner. Our interpretation methodology was validated successfully with core/log data from the Middle East. The facies ranged from mudstone to grainstone.

To address developmental regulation of pulmonary vascular O2 sensing, we tested the hypotheses that 1) fetal but not adult pulmonary artery smooth muscle cells (PASMCs) can directly sense an acute increase in O2, 2) Ca2+-sensitive K+(KCa) channel activity decreases with maturation, and 3) PASMC KCa channel expression decreases with maturation. We used fluorescence microscopy to confirm that fetal but not adult PASMCs are able to sense an acute increase in O2tension. Acute normoxia induced a 22 ± 2% decrease in cytosolic Ca2+ concentration ([Ca2+]i) in fetal PASMCs and no change in [Ca2+]i in adult PASMCs ( P < 0.01). The effects of K+channel antagonists were studied on fetal and adult PASMC [Ca2+]i. Iberiotoxin (10−9 M) caused PASMC [Ca2+]i to increase by 694 ± 22% in the fetus and caused no change in adult PASMCs. KCa channel expression and mRNA levels in distal pulmonary arteries from fetal and adult sheep were examined. Both KCachannel protein and mRNA expression in the distal pulmonary vasculature decreased with maturation. We conclude that maturation-dependent changes in PASMC O2 sensing render the fetal PASMCs uniquely sensitive to an acute increase in O2 tension at a biologically critical time point.

This paper was prepared for presentation at the 8th Abu Dhabi International Petroleum Exhibition and Conference held in Abu Dhabi, U.A.E., 11-14 October 1998.

1. Candoxatrilat, an active neutral endopeptidase inhibitor, was released rapidly from the inactive prodrug candoxatril in vivo in mouse, rat, rabbit, dog and man. 2. Oral doses of [14C]-candoxatril were cleared rapidly, mostly by ester hydrolysis to candoxatrilat, in mouse, dog and man. A complementary intravenous study in man with [14C]-candoxatrilat showed that the active drug was virtually completely renally cleared. Neither candoxatril nor candoxatrilat underwent chiral inversion in man. 3. Systemic availability of candoxatrilat from the oral prodrug was estimated to be 88, 53, 42, 17 and 32% in mouse, rat, rabbit, dog and man respectively. Plasma clearance of candoxatril was too rapid to enable pharmacokinetic parameter calculation in mouse and rabbit; for man, the apparent oral clearance was 57.9 ml/min/kg and the elimination half-life was 0.46 h. 4. For intravenous candoxatrilat, total plasma clearance values were 32, 15, 5.5, 5.8 and 1.9 ml/min/kg for mouse, rat, rabbit, dog and man respectively. Renal clearance values were 8.7, 7.2, 2.9 and 1.7 ml/min/kg for mouse, rat, dog and man and these approximate to the respective glomerular filtration rates. Allometric scaling with respect to bodyweight across the species allowed reasonable prediction of the above two clearance parameters in man.

Abstract We performed laboratory measurements to determine whether NMR logging would improve log evaluation of the Mubarraz Field. The Mubarraz Field is a carbonate field in offshore Abu Dhabi, that produces from the Cretaceous Thamama Group. Existing log evaluation using classical logs has some shortcomings. Some zones that are not highly resistive actually produce water-free oil. This is because Mubarraz samples often have a large amount of microporosity. The microporosity occurs because samples are highly micritized, and grain-sized particles are generally peloidal with internal microporosity. The microporosity holds a large volume of capillary-bound water, which results in low resistivities in zones that still have producible oil in large pores. An additional evaluation problem is that permeability varies widely while porosity remains almost constant. As a result, permeability vs. porosity correlations are less valuable than normal. In laboratory measurements on Mubarraz samples, we found that NMR relaxation measurements can provide:–good estimation of the capillary-bound water volume at an air/water capillary pressure of 25 psi, using a cutoff on NMR T2 relaxation time of 190 ms.–good identification of the grainstones as opposed to the lower-permeability textures (packstone… mudstone) with a T2 threshold of about 225 milliseconds.–estimates of permeability that are significantly better than can be obtained from porosity alone. NMR relaxation measurements contain information about the pore size distribution, and it is this information that permits estimation of production-governing parameters. The estimators are based on parameters that can be obtained from continuous NMR logging. P. 477

To meet the helium (He) requirements of the superconducting supercollider (SSC), the cryogenic plants must be able to respond to time-varying loads. Thus the design and simulation of the cryogenic plants requires dynamic models of their principal components, and in particular, the core heat exchangers. In this paper, we detail the derivation and computer implementation of a model for core heat exchangers consisting of three partial differential equations (PDEs) for each fluid stream (the continuity, energy and momentum balances for the He), and one PDE for each parting sheet (the energy balance for the parting sheet metal); the PDEs have time and axial position along the exchanger as independent variables. The computer code can accommodate any number of fluid streams and parting sheets in an adiabatic group. Features of the code include: rigorous or approximate thermodynamic properties for He, upwind and downwind approximation of the PDE spatial derivatives, and sparse matrix time integration. The outputs from the code include the time-dependent axial profiles of the fluid He mass flux, density, pressure, temperature, internal energy and enthalpy. The code is written in transportable Fortran 77, and can therefore be executed on essentially any computer.

1. Broilers were grown on diets containing processed poultry wastes: dehydrated broiler litter, with (DBLA) or without (DBLN) arsenical residues, “in‐house” dried waste (IHDW) and dehydrated layer waste (DLW), all from commercial poultry houses. 2. Wastes were included at 100 g/kg in starter and finisher diets given, in most cases, from 0 to 8 weeks. In formulation the contents of true protein and of experimentally‐determined metabolisable energy values were used to ensure nutritional balance. 3. Body weight at 8 weeks with inclusion of wastes was equivalent to control (DLW) or increased (DBLA, DBLN). The gain: food ratio was reduced by the two layer wastes because of increased food consumption. Litter moisture was increased by the feeding of wastes.

Studies in which the rate of local cerebral blood flow is determined by xenon-enhanced computerized tomography require measurement of end-tidal gas. A mass spectrometer and a thermoconductivity detector were compared in measuring the concentration of xenon in end-tidal gas both in humans and in a clinically simulated ("breathing bag") system. The experiments showed that the two instruments provided virtually identical results up to a rate of 18 breaths/min, at which rate recorded concentrations showed marginal degradation with the thermoconductivity detector. Given the absence of a significant difference in the ability of the mass spectrometer and the thermoconductivity detector to measure end-tidal xenon concentration, the thermoconductivity detector appears to be a satisfactory alternative in studies measuring the rate of local cerebral blood flow by enhanced computerized tomography.

Errors in the determination of xenon concentrations in arterial blood during inhalation of xenon-oxygen mixtures are used to assess errors in the derivation of regional cerebral blood flow by the xenon-enhanced computed tomography (CT) method. The results of this study indicate that approximating the arterial buildup by a single exponential introduces relatively small errors in estimated flow values. The most significant systematic error is introduced by errors in estimation of the xenon arrival time to the brain in relationship to sequential (CT) scanning times.