Efficient crystal structure materials as reactive sorbent for the CO2 and CH4 adsorption and storage.

The efficient dirubidium cobalt bis(dihydrogendiphosphate) dihydrate compound is successfully synthesized in a solution and used as a reactive sorbent for the CO2 and CH4 gases adsorption and storage. A crystal of this Rb2Co(H2P2O7)2·2H2O compound has been isolated and characterized by single X-ray diffraction analysis and was found to crystallize in the triclinic system ( P 1 ¯ ) with the cell parameters (Å): 6.980(1), 7.370(1), 7.816(1), 81.74(1), 70.35(1), 86.34(1); V = 374.68(9) Å3, Z = 2. The crystal-packing consists of a three-dimensional framework made upon corners and edges sharing of [RbO7], [H2P2O7] and [CoO6] entities, furthermore linked by a network of H-bonds. The UV-Vis spectroscopy revealed usual transitions between the ground state 4T1g and the upper levels 4T2g, 4A2g and 4T1g (P). Moreover, the CO2 and CH4 gases sorption measurements were successfully performed at two different temperatures (25 and 45 °C) and various pressures ranging from vacuum to 50 bar. Our results show that rate of CO2 and CH4 capturing was 3.10 mmol/g and 2.35 mmol/g at temperature 25 °C and pressure 50 bar, respectively. This compound showed a clear potential for CO2/CH4 adsorption and storage thereby paving the way towards its exploration and adaptation for capturing and collecting carbon dioxide and greenhouse gases from the air, and their conversion into hydrocarbon fuels using existing mature technologies. We have also conducted density functional theory calculations to study the CO2 and CH4 adsorption properties of Rb2Co(H2P2O7)2·2H2O. The simulation results show enhanced adsorption of both types of molecules on the surface of the material.

α-Na2Ni2Fe(PO4)3: a dual positive/negative electrode material for sodium ion batteries.

A new orthophosphate α-Na2Ni2Fe(PO4)3 was synthesized using a solid state reaction route, and its crystal structure was determined from powder X-ray diffraction data. The physical properties of α-Na2Ni2Fe(PO4)3 were studied by magnetic and electrochemical measurements and by Mössbauer and Raman spectroscopy. α-Na2Ni2Fe(PO4)3 crystallizes according to a stuffed α-CrPO4-type structure with the space group Imma and the cell parameters a = 10.42821(12), b = 13.19862(15), c = 6.47634(8) Å, and Z = 4. The structure consists of a 3D-framework of octahedra and tetrahedra sharing corners and/or edges with channels along [100] and [010], in which the sodium atoms are located. The (57)Fe Mössbauer spectrum indicates that the Fe(3+) cation is distributed over two crystallographic sites implying the presence of a Ni(2+)/Fe(3+) statistical disorder. Magnetic susceptibility follows the Curie-Weiss behavior above 100 K with θ = -114.3 K indicating the occurrence of predominant antiferromagnetic interactions. Electrochemical tests indicate that during the first discharge to 1 V vs. Na(+)/Na in a sodium cell, one Na(+) ion could be inserted into the α-Na2Ni2Fe(PO4)3 structure. This has led to the formation of a new phase Na3Ni2Fe(PO4)3 which was found to be promising as a positive electrode material for sodium batteries. When α-Na2Ni2Fe(PO4)3 is further discharged to 0.03 V, it delivers a capacity of 960 mA h g(-1). This corresponds to the intercalation of more than seven sodium atoms per formula unit which is an indication of a conversion-type behaviour with the formation of metallic Fe and Ni. When cycled in the voltage range 0.03-3 V vs. Na(+)/Na, at 20 °C, under the current rates of 50, 100, 200, and 400 mA g(-1), reversible capacities of 238, 196, 153, and 115 mA h g(-1), were obtained, respectively.

Direct inhibitory effect of glucocorticoids on corticotrophin-releasing hormone gene expression in neurones of the paraventricular nucleus in rat hypothalamic organotypic cultures.

Corticotrophin-releasing hormone (CRH) in the parvocellular neurosecretory neurones of hypothalamic paraventricular nucleus governs neuroendocrine stress cascade and is the major target of the negative feedback effect of corticosteroids. To assess whether glucocorticoids exert their inhibitory effect on CRH expression directly on parvocellular neurones or indirectly through a complex neuronal circuit, we examined the effect of corticosterone (CORT) and dexamethasone (DEX) on CRH mRNA levels in slice explant cultures of the rat hypothalamus. Organotypic slice cultures were prepared from 6 days old rat pups and maintained in vitro for 14 days. CRH mRNA expression was measured by in situ hybridisation histochemistry. Under basal conditions, CRH mRNA expressing cells were exclusively revealed in the paraventricular region along the third ventricle. Inhibition of action potential spike activity by tetrodotoxin (TTX, 1 microm) reduced CRH mRNA signal in the organotypic cultures. CORT (500 nm) or DEX (50 nm) treatment for 24 h significantly inhibited CRH expression in the parvocellular neurones and this effect of corticosteroids was not affected following blockade of voltage dependent sodium channels by TTX. Forskolin-stimulated CRH mRNA levels in the paraventricular nucleus were also inhibited by CORT or DEX in the presence and in the absence of TTX. These studies identify paraventricular CRH neurones as direct target of corticosteroid feedback. Type II corticosteroid receptor agonists act directly on paraventricular neurones to inhibit basal and forskolin-induced CRH mRNA expression in explant cultures of the rat hypothalamus.

GABAergic mechanisms constraining the activity of the hypothalamo-pituitary-adrenocortical axis.

There are two major inhibitory mechanisms that constrain the activity of the hypothalamo-pituitary-adrenocortical axis: the hormonal negative feedback and the neural inhibition including that posed by the GABAergic neurons. This chapter summarizes our recent morphologic and functional findings on the role of gamma-aminobutyric acid (GABA) in the transcriptional regulation of hypophyseotropic neuropeptide genes in the parvocellular neurosecretory cells of the hypothalamic paraventricular nucleus (PVH). We used organotypic hypothalamic slice cultures and in vivo microinjection protocols in combination with in situ histologic and ultrastructural procedures to address the role of local interneurons in the regulation of hypothalamic effector neurons. Under basal conditions, an intrinsic GABAergic mechanism in the PVH microenvironment was revealed that by itself, without limbic contribution, impinged a tonic inhibitory influence on the parvocellular corticotropin-releasing hormone (CRH) neurons in vitro. In vivo, remote inputs were superimposed on the local circuit, allowing differential transcriptional regulation of CRH and arginine vasopressin (AVP) genes in the hypophyseotropic neurons. During stress, GABAergic cells that are known to project to the PVH become activated and are involved in restraining the cellular, transcriptional, and hormonal responses to stress.

Methyl 3-para-anisyl-4-(2-hydroxybenzoyl)isoxazole-5-carboxylate.

The title compound, C(19)H(15)NO(6), contains a planar isoxazole ring. An intramolecular hydrogen bond is formed between the OH group attached to a phenyl ring and a carbonyl O atom.

1,2,4-Triazolo[2,3-h]-7,9-thiaza-11-crown-4.

The title compound, 4,7-dioxa-10-thia-1,12,13-triazabicyclo[9.3.0]tetradeca-11,13-diene, C(8)H(13)N(3)O(2)S, contains an 11-membered ring, which appears in a chair conformation and has approximate mirror symmetry. It may be used for the complexation of metal atoms.

4-Acetonylidene-1-ethyl-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one.

The title compound, C(14)H(16)N(2)O(2), contains a diazepine ring, which appears in a boat conformation. An intramolecular hydrogen bond is formed between the NH group of the diazepine ring and a carbonyl O atom of one of the side chains.

[Clinical assessment of free serum prostate specific antigen (PSA)]. / Evaluation clinique de la mesure de l'antigène spécifique de la prostate (PSA) sous sa forme libre sérique.

The prostate specific antigen (PSA) level represents all of the immunoreactive serum PSA, either free or bound to alpha-1-anti-chymotrypsin. Isolated assay of free PSA has demonstrated a higher free PSA/total PSA ratio in cases of benign prostatic hyperplasia (BPH) than in cases of cancer, suggesting the possible use of this ratio in the detection of prostatic cancer when the PSA level is between 4 and 10 ng/mL. We retrospectively assayed free PSA in 64 cases of localized prostate cancer, 90 cases of BPH before transurethral resection and 59 healthy controls. By comparing the mean values of the 3 populations and the ROC curves, we confirmed the superiority of the free PSA/total PSA ratio over total PSA in the detection of prostatic cancer, but these results, established in a retrospectively constituted population, need to be confirmed by prospective epidemiological studies. Nevertheless, in routine urological practice, we propose that free PSA assay be performed in all men with a PSA level between 4 and 10 ng/mL and a normal prostate on digital rectal examination.

[Bilateral splanchnicectomy by transhiatal approach in pain of pancreatic origin. 37 cases]. / Splanchnicectomie bilatérale par voie trans-hiatale dans les douleurs d'origine pancréatique. 37 observations.

OBJECTIVES: Surgical splanchnicectomy remains a useful means to relieve pain induced by malignant tumours of the pancreas and chronic pancreatitis. We report our experience in 37 patients. METHODS: Between 1983 and 1993, 37 patients underwent transhiatal bilateral splanchnicectomy; 32 had a non-resectable adenocarcinoma and 5 chronic pancreatitis. In all cases, morphine had been required for pain relief. RESULTS: Symptomatic pain relief was immediately achieved, with complete sedation in 84.3% of the cases. Prolonged antalgic effect continued for the survival period in 84.3%. Mean post-operative follow-up was 12.7 weeks corresponding to mean survival in 32 patients with pancreatic tumour. Post-operative mortality was 21.6% with no direct relationship with neurectomy. Specific morbidity related to pleural drainage was 10.8%. CONCLUSION: Compared with other surgical procedures, trans-hiatal bilateral splanchnicectomy is a simple technique which can be performed whatever the stage of the locoregional tumour extension. In patients without an indication for exploratory laparoscopy, percutaneous chemical neurolysis is still indicated, even if the long-term result is less effective. In case of failure or technical impossibilities, thoracoscopic splanchnicectomy should be performed.

[Preliminary study of the feasibility of intraoperative ultrasonography of the biliary tract during cholecystectomy under celioscopy]. / Etude préliminaire de la faisabilité de l'échographie peropératoire des voies biliaires au cours des cholécystectomies par coelioscopie.

Peroperative echography and cholangiography provide similar information during the exploration of the biliary tree for conventional surgery for gall stones. Peroperative cholangiography is more difficult to perform via the coeolioscope with a failure rate of 10% in the most skillful teams. We investigated the technical feasibility of peroperative echography during coeliosurgery for gall stones. The technique was performed in 13 patients using a pulsed Doppler 7.5 MHz scan laparoscope. The entire biliary tree was successfully imaged in 12 patients and the three structures of the hepatic pedicle were identified in all cases. The exploration took less than 10 minutes and there was no morbidity. One gall stone was discovered and endoscopic sphincterotomy was performed immediately. None of the patients presented signs suggesting residual lithiasis with a mean follow-up of 2 months. This preliminary study suggests that the technique is very favourably feasible and may play an important role in the exploration of the bile tract during coelioscopic cholecystectomy.

[Pelvic lipomatosis. A case with ureteral and venous obstruction]. / Lipomatose pelvienne. A propos d'un cas avec obstruction urétérale et veineuse.

The authors report a case of pelvic lipomatosis in a 62 year old man associated with venous obstruction (third case reported in the literature), diagnosed after bilateral ureteric obstruction, and review of the literature on this subject. The diagnosis was suggested by the radiological triad of hyperlucency of the pelvis on plain abdominal X-ray, "hot air balloon" appearance of the bladder on IVU and a rigid and ascended rectosigmoid on barium enema, and was confirmed by CT and MRI. Treatment combining corticosteroids and urinary tract disinfection was partially effective. A double J ureteric stent resolved the problem of persistent right ureteric obstruction.

[Long-term results of urethrectomy following termino-terminal urethrorrhapy for urethral stenosis. A study of 18 cases]. / Résultats à long terme des urétrectomies suivies d'urétrorraphie termino-terminale pour sténose de l'urètre. Etude de dix-huit cas.

Urethrectomy followed by terminoterminal urethrorraphy is one of the oldest surgical techniques for treating short urethral stenoses, regardless of their location. Eighteen patients managed by this technique were followed-up for at least ten years. Results were satisfactory in four out of every five cases and success was nearly immediate. No delayed deteriorations were seen. These limitations are mainly related to the length of the lesion.