VAPO as catalyst for liquid phase oxidation reactions

Abstract The preparation, characterisation and catalytic properties of vanadium containing aluminophosphate molecular sieves (type AEL and AbT) are described in this paper. The molecular sieves were prepared by post-synthesis treatment and hydrothermal procedures. Several parameters were varied: nature of the template, crystallisation procedure and vanadium content. Tri-propylamine appeared to be the best template for the preparation of VAPO-5: highly crystalline, homogeneous batches (crystallite size: 2x I x 1 ~tm) with a maximum of about 2 wt% vanadium could be obtained in high yield (75-80%). Crystallographically pure VAPO-11 with a maximum of only 0.5 wt% of vanadium could be prepared. In VAPO the incorporation mode of vanadium gradually changes from tetra-to penta-coordinated when the amount of vanadium is increased. However the formation of vanadium pentoxide could not be detected. The vanadium containing molecular sieves were used as catalyst for the oxidation of allylic and secondary alcohols by tert-butyl hydroperoxide in the liquid phase. Compared with a homogeneous catalyst, bis(2,4-pentandionato)-oxovanadium(IV) (VO(acac)2), the activity of vanadium containing molecular sieves is a factor 3-100 times lower. The activity of VAPO becomes higher when the vanadium content is increased. The decomposition rate of the peroxide is influenced by the pore structure, whereas no other effects on the selectivity are found

Oxidation of linear alcohols with hydrogen peroxide over titanium silicate-1

Abatract In this paper different parameters affecting the oxidation of alcohols with hydrogen peroxide are described. The influence of the amount and of the crystallite size of the catalyst, as well as the concentrations of hydrogen peroxide and substrate have been studied. The influence of the reaction temperature, the chain length of the alcohol (C6, C7, C8 and C9 ) and the position of the alcohol group (a, /3 or y) on the reaction rate has also been investigated. As a result of this study it can be reported that the reaction is first order with respect to the amount of catalyst and the hydrogen peroxide concentration, and zero order in alcohol concentration. The activation energy for the oxidation of 2-octanol is 71 kJ/ mol. The particle size has a considerable effect on the reaction rate; larger particles result slower reaction. There is a remarkable effect of the chain length on the reaction rate (C6<C7<C8% C9) and the position of the hydroxyl group has a strong effect on the activity of TS-1 (fl> (Y > y ) . The crystallite size effect can be explained by means of diffusion limitations, as could be illustrated by Weisz modulus calculations. The observed difference in activity between jI and y alcohols can not be related to differences in diffusion (single component diffusion of /I and y alcohols show little difference) and therefore transition state restrictions of the alcohols in the pores of the TS-1 may be a possible explanation for this effect

Quality of life in Dutch patients with primary biliary cholangitis:Discrepancies between patients’ perspectives and objective disease parameters

Aim: This study aims to assess the health-related quality of life (HRQoL) in a Dutch population of patients with primary biliary cholangitis (PBC) in relation to the prognosis and need for second line-therapy, based on both objective disease parameters and patients’ perspectives. Methods: In this cross-sectional multicenter study, HRQoL was assessed by using the Dutch PBC-40 according to objective clinical parameters and patients’ perspectives on treatment and prognosis. Results: In total, 178/269 (66%) patients responded; mean age 61.2 (SD 9.9) years and 165 (92.7%) women. The PBC-40 domain scores did not differ according to the GLOBE score response (p &gt; 0.05 for all) or according to the POISE criteria (p &gt; 0.05), except for the domain itch (p = 0.031). Patients who considered their survival to be impaired scored higher on all domains as compared to those expecting a normal prognosis (p &lt; 0.05). Similarly, PBC-40 domain scores were higher among patients who considered that they were in need of additional therapy compared to those who did not (p &lt; 0.05 for all, except for domain itch [p = 0.056]). However, 45/62 (72.6%) patients with a self-expected impaired prognosis had a GLOBE score indicative of a normal prognosis. Twenty-five of the 40 (62.5%) patients who believed they needed additional therapy were below POISE criteria. Conclusion: The HRQoL of patients with PBC was impaired in terms of nonfavorable disease status according to the expectations of patients, but not according to objective disease parameters. Substantial discrepancies between patients’ perspectives and objective parameters were observed, which highlights the need for better patient guidance among patient with PBC.</p

Kinetoplastid kinetochore proteins KKT14–KKT15 are divergent Bub1/BubR1–Bub3 proteins

Faithful transmission of genetic material is crucial for the survival of all organisms. In many eukaryotes, a feedback control mechanism called the spindle checkpoint ensures chromosome segregation fidelity by delaying cell cycle progression until all chromosomes achieve proper attachment to the mitotic spindle. Kinetochores are the macromolecular complexes that act as the interface between chromosomes and spindle microtubules. While most eukaryotes have canonical kinetochore proteins that are widely conserved, kinetoplastids such as Trypanosoma brucei have a seemingly unique set of kinetochore proteins including KKT1–25. It remains poorly understood how kinetoplastids regulate cell cycle progression or ensure chromosome segregation fidelity. Here, we report a crystal structure of the C-terminal domain of KKT14 from Apiculatamorpha spiralis and uncover that it is a pseudokinase. Its structure is most similar to the kinase domain of a spindle checkpoint protein Bub1. In addition, KKT14 has a putative ABBA motif that is present in Bub1 and its paralogue BubR1. We also find that the N-terminal part of KKT14 interacts with KKT15, whose WD40 repeat beta-propeller is phylogenetically closely related to a direct interactor of Bub1/BubR1 called Bub3. Our findings indicate that KKT14–KKT15 are divergent orthologues of Bub1/BubR1–Bub3, which promote accurate chromosome segregation in trypanosomes

Determination of the Oswestry Disability Index score equivalent to a "satisfactory symptom state" in patients undergoing surgery for degenerative disorders of the lumbar spine-a Spine Tango registry-based study.

BACKGROUND CONTEXT The achievement of a given change score on a valid outcome instrument is commonly used to indicate whether a clinically relevant change has occurred after spine surgery. However, the achievement of such a change score can be dependent on baseline values and does not necessarily indicate whether the patient is satisfied with the current state. The achievement of an absolute score equivalent to a patient acceptable symptom state (PASS) may be a more stringent measure to indicate treatment success. PURPOSE This study aimed to estimate the score on the Oswestry Disability Index (ODI, version 2.1a; 0-100) corresponding to a PASS in patients who had undergone surgery for degenerative disorders of the lumbar spine. STUDY DESIGN/SETTING This is a cross-sectional study of diagnostic accuracy using follow-up data from an international spine surgery registry. PATIENT SAMPLE The sample includes 1,288 patients with degenerative lumbar spine disorders who had undergone elective spine surgery, registered in the EUROSPINE Spine Tango Spine Surgery Registry. OUTCOME MEASURES The main outcome measure was the ODI (version 2.1a). METHODS Surgical data and data from the ODI and Core Outcome Measures Index (COMI) were included to determine the ODI threshold equivalent to PASS at 1 year (±1.5 months; n=780) and 2 years (±2 months; n=508) postoperatively. The symptom-specific well-being item of the COMI was used as the external criterion in the receiver operating characteristic (ROC) analysis to determine the ODI threshold equivalent to PASS. Separate sensitivity analyses were performed based on the different definitions of an "acceptable state" and for subgroups of patients. JF is a copyright holder of the ODI. RESULTS The ODI threshold for PASS was 22, irrespective of the time of follow-up (area under the curve [AUC]: 0.89 [sensitivity {Se}: 78.3%, specificity {Sp}: 82.1%] and AUC: 0.91 [Se: 80.7%, Sp: 85.6] for the 1- and 2-year follow-ups, respectively). Sensitivity analyses showed that the absolute ODI-22 threshold for the two follow-up time-points were robust. A stricter definition of PASS resulted in lower ODI thresholds, varying from 16 (AUC=0.89; Se: 80.2%, Sp: 82.0%) to 18 (AUC=0.90; Se: 82.4%, Sp: 80.4%) depending on the time of follow-up. CONCLUSIONS An ODI score ≤22 indicates the achievement of an acceptable symptom state and can hence be used as a criterion of treatment success alongside the commonly used change score measures. At the individual level, the threshold could be used to indicate whether or not a patient with a lumbar spine disorder is a "responder" after elective surgery

Variation in grouping patterns, mating systems and social structure: what socio-ecological models attempt to explain

Socio-ecological models aim to predict the variation in social systems based on a limited number of ecological parameters. Since the 1960s, the original model has taken two paths: one relating to grouping patterns and mating systems and one relating to grouping patterns and female social structure. Here, we review the basic ideas specifically with regard to non-human primates, present new results and point to open questions. While most primates live in permanent groups and exhibit female defence polygyny, recent studies indicate more flexibility with cooperative male resource defence occurring repeatedly in all radiations. In contrast to other animals, the potential link between ecology and these mating systems remains, however, largely unexplored. The model of the ecology of female social structure has often been deemed successful, but has recently been criticized. We show that the predicted association of agonistic rates and despotism (directional consistency of relationships) was not supported in a comparative test. The overall variation in despotism is probably due to phylogenetic grade shifts. At the same time, it varies within clades more or less in the direction predicted by the model. This suggests that the model's utility may lie in predicting social variation within but not across clades