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Large, inert, weakly basic carborane anions of the icosahedral type CHB(11)R(5)X(6)(-) (R = H, Me; X = Cl, Br) allow ready isolation and structural characterization of discrete salts of the solvated proton, [H(solvent)(x)][CHB(11)R(5)X(6)], (solvent = common O-atom donor). These oxonium ion Brønsted acids are convenient reagents for the tuned delivery of protons to organic solvents with a specified number of donor solvent molecules and with acidities leveled to those of the chosen donor solvent. They have greater thermal stability than the popular [H(OEt(2))(2)][BAr(F)] acids based on fluorinated tetraphenylborate counterions because carborane anions can sustain much higher levels of acidity. When organic O-atom donors such as diethyl ether, tetrahydrofuran, benzophenone, and nitrobenzene are involved, the coordination number of the proton (x) in [H(solvent)(x)()](+) is two. A mixed species involving the [H(H(2)O)(diethyl ether)](+) ion has also been isolated. These solid-state structures provide expectations for the predominant molecular structures of solvated protons in solution and take into account that water is an inevitable impurity in organic solvents. The O.O distances are all short, lying within the range from 2.35 to 2.48 A. They are consistent with strong, linear O.H.O hydrogen bonding. Density functional theory calculations indicate that all H(solvent)(2)(+) cations have low barriers to movement of the proton within an interval along the O.H.O trajectory, i.e., they are examples of so-called SSLB H-bonds (short, strong, low-barrier). Unusually broadened IR bands, diagnostic of SSLB H-bonds, are observed in these H(solvent)(2)(+) cations.

A new class of low-melting N,N'-dialkylimidazolium salts has been prepared with carborane counterions, some of the most inert and least nucleophilic anions presently known. The cations and anions have been systematically varied with combinations of 1-ethyl-3-methyl-(EMIM+), 1-octyl-3-methyl-(OMIM+), 1-ethyl-2,3-dimethyl-(EDMIM+), and 1-butyl-2,3-dimethyl-(BDMIM+) imidazolium cations and CB11H12-, CB11H6Cl6-, and CB11H6Br6- carborane anions to elucidate the factors which affect their melting points. From trends in melting points, which range from 156 °C down to 45 °C, it is clear that the alkylation pattern on the imidazolium cation is the main determinant of melting point and that packing inefficiency of the cation is the intrinsic cause of low melting points. C-Alkylation of the anion can also contribute to low melting points by the introduction of a further packing inefficiency. Nine of the thirteen salts have been the subject of X-ray crystal structural determination. Notably, crystallographic disorder of the cation is observed in all but one of these salts. It is the most direct evidence to date that packing inefficiency is the major reason unsymmetrical N,N'-dialkylimidazolium salts can be liquids at room temperature.

Objectives Four antenatal visits, delivery in a health facility, and three postnatal visits are the World Health Organization recommendations for women to optimize maternal health outcomes. This study examines maternal compliance with the full recommended maternal health visits in rural Tanzania with the goal of illuminating interventions to reduce inequalities in maternal health. Methods Analysis included 907 women who had given birth within two years preceding a survey of women of reproductive age. Multinomial logistic regression was used to assess the influence of maternal, household, and community-level characteristics on four alternative classes defining relative compliance with optimal configuration of maternal health care seeking behavior. Results Parity, wealth index, timeliness of ANC initiation, nearest health facility type, religion, and district of residence were significant predictors of maternal health care seeking when adjusted for other factors. Multiparous women compared to primiparous were less likely to seek care at the high level [RRR 0.16, 95 % confidence interval (CI) 0.06-0.46], at the mid-level (RRR 0.22, 95 % CI 0.09-0.58), and the mid-low level (RRR 0.27, 95 % CI 0.09-0.80). Women in the highest wealth index compared to those in the poorest group were almost three times more likely to seek the highest two levels of care versus the lowest level (high RRR 2.92, 95 % CI 1.27-6.71, mid-level RRR 2.71, 95 % 1.31-5.62). Conclusion Results suggest that efforts to improve the overall impact of services on the continuum of care in rural Tanzania would derive particular benefit from strategies that improve maternal health coverage among multiparous and low socioeconomic status women., Author(s): Anna Larsen[sup.1] , Amon Exavery[sup.2] , James F. Phillips[sup.1] , Kassimu Tani[sup.2] , Almamy M. Kante[sup.1] [sup.2] Author Affiliations: (1) Columbia University Mailman School of Public Health, 60 Haven [...]

Cancer patients undergo long periods of treatment and follow-up, and it is challenging to keep track of appointments, treatment plans etc. This paper report from a study involving 41 patients and next-of-kin focusing on their strategies for managing the patient journey. Most patients take an active role, employing a variety of tools. The national patient portal is seen as useful for accessing information and keeping an overview but does not alone meet their information needs. [ABSTRACT FROM AUTHOR]

Synthesis, structure, and NMR spectroscopic data for [(closo-C[B.sub.11] [H.sub.6][Br.sub.6])PtMe3] are reported. This neutral platinum(IV) complex contains the closo-C[B.sub.11][H.sub.6][Br.sub.6.sup.-] anion bonded to the trimethylplatinum(IV) cation via three boron-bound bromines. Closo-C[B.sub.11][H.sub.6][Br.sub.6.sup.-], which often acts as weakly coordinating or even non-coordinating anion, adopts here a role still very rare for this anion: it acts as a tripodal capping ligand enabling a pseudo-octahedral geometry at a [d.sup.6] metal center. Three bromines from the lower hemisphere of the hexahalogenated carboranate coordinate to Pt(IV), and distortions from ideal octahedral angles at Pt are marginal ( Key words: non-coordinating anion, platinum(IV), trimethyl, closo-carboranate, tripodal, trans-influence, NMR spectroscopy. On a realise la synthese et on a determine la structure et les donnees de spectroscopie RMN relative au [(closo-C[B.sub.11][H.sub.6][Br.sub.6])Pt[Me.sub.3]]. Ce complexe neutre de platine(IV) contient un anion closo-C[B.sub.11][H.sub.6][Br.sub.6.sup.-] lie a un cation trimethylplatine(IV) par le biais de trois atomes de bore lies a des atomes de brome. L'anion closo-C[B.sub.11][H.sub.6][Br.sub.6.sup.-] qui agit souvent comme un anion de coordination faible, qui est meme quelquefois non coordinant, adopte dans notre cas un role encore plus rare pour cet anion, a savoir celui de ligand tripode qui sert de cap et qui permet d'avoir une geometrie pseudo-tetraedrique au niveau [d.sup.6] du centre metallique. Les trois atomes de brome de la partie inferieure de l'hemisphere du carboranate hexahalogene se lient par coordination au Pt(IV) et les distorsions par rapport aux angles octaedriques ideaux au niveau du platine sont marginales ( Mots-cles: anion non coordinant, platine(IV), trimethyle, closo-carboranate, tripode, influence trans, spectroscopie RMN. Traduit par la Redaction], Introduction The development of noncoordinating (or very weakly coordinating) anions has led to tremendous progress in the field of highly Brinsted-acidic or Lewis-acidic species (1). Closo-carboranates (2) have proven excellent [...]

Introduction: A recent randomised controlled trial compared three combined treatments for plantar fasciopathy (PF) and found no clinically relevant between-group differences. Understanding which patient characteristics can predict response to treatment may help clinicians choose the most suitable treatment for their patients. Objectives: This study aims to explore patient characteristics associated with a successful outcome of different combined treatments for patients with PF. Study design: An ancillary analysis of a three-armed randomized controlled trial (the FIX-Heel Trial) comparing three combined treatment approaches to PF. Methods: The association between patient characteristics collected at baseline and the outcome of one of the three treatment approaches: 1) advice plus insoles (PA), 2) PA and exercises (PAX), and 3) PAX and corticosteroid injection (PAXI) were explored. 180 patients with PF were included in the trial. The primary analysis is a logistic regression to analyse a possible association of sex, age, BMI, symptom duration, pain during the past week on a 0-100 mm VAS, number of PF episodes, and sedentary behaviour with a successful outcome of treatment after 12 weeks. A successful outcome is defined as a minimal clinically important change (14.1 points) in the Foot Health Status Questionnaire pain domain. Results: Preliminary results from univariate complete-case analyses indicate that pain during the past week is negatively associated with a successful outcome with odds ratios of 0.95 (95%CI: 0.91;0.99], P=0.014) and 0.91 (95%CI: 0.86;0.97, P= 0.005) in PA and PAX, respectively. Symptom duration seems negatively associated with a successful outcome with an odds ratio of 0.9 (95%CI: 0.83;0.97 P= 0.006) in PAXI. Final results, including secondary analyses, will be presented at the conference. Conclusion: Less pain during the past week in PA and PAX and shorter symptom duration in PAXI may be associated with a successful outcome of treatment after 12 weeks. [ABSTRACT FROM AUTHOR]