Epoxidation of propylene with dilute H2O2 over titanium silicalite containing trace aluminum

Titanium silicalite (TS-1) was successfully synthesized by using TPABr as the template and silica sol as silicon source in a 100 l stainless steel autoclave. IR, XRD, UV--vis, elemental analysis, and (2)7Al and (3)1P MAS NMR were used to characterize the synthesized products. The results show that the synthesized material has an MFI structure with high crystallinity and large crystal size and two kinds of titanium species. Trace aluminum in silica sol is also incorporated into the zeolite framework. The synthesized TS-1 exhibits high activity in the epoxidation of propylene with dilute H2O2 with high selectivity to methyl mono-ethers and low selectivity to propylene oxide (PO). The low selectivity toward PO is due to the residual acidity onto TS-1. The selectivity of PO can reach up to 90% through adjusting the pH of the reaction mixture. Extra amounts of base decrease the H2O2 utilization and the H2O2 conversion. However, in over acid-treated TS-1 in which part removal of extra-framework titanium takes place, the utilization of H2O2 is quite different: for the low Si/Ti ratio of TS-1, the H2O2 utilization increases. But the utilization of H2O2 does not change for the high Si/Ti ratio TS-1. Thermal analysis shows that the as-synthesized TS-1 exhibits high activity and thermal stability in the calcined range 540-900 degreesC.

Measuring Bottleneck Bandwidth of Targeted Path Segments

Accurate measurement of network bandwidth is crucial for flexible Internet applications and protocols which actively manage and dynamically adapt to changing utilization of network resources. These applications must do so to perform tasks such as distributing and delivering high-bandwidth media, scheduling service requests and performing admission control. Extensive work has focused on two approaches to measuring bandwidth: measuring it hop-by-hop, and measuring it end-to-end along a path. Unfortunately, best-practice techniques for the former are inefficient and techniques for the latter are only able to observe bottlenecks visible at end-to-end scope. In this paper, we develop and simulate end-to-end probing methods which can measure bottleneck bandwidth along arbitrary, targeted subpaths of a path in the network, including subpaths shared by a set of flows. As another important contribution, we describe a number of practical applications which we foresee as standing to benefit from solutions to this problem, especially in emerging, flexible network architectures such as overlay networks, ad-hoc networks, peer-to-peer architectures and massively accessed content servers.

CONSERVATIVE AND PROGFESSIVE ASPECTS OF THE SONATA FROM LATE BEETHOVEN TO PROKOFIEV

The term 'sonata' arose in the early seventeenth-century Baroque period and was originally used to distinguish instrumental (sonata) music from vocal music. Later. the sonata style, as a reliable yet flexible compositional framework, was extensively shaped and utilized throughout the Classical period. Subsequently, in the Romantic period, freer creative, individualistic. and expressive musical elements began to be preferred by composers in their use of harmonj., tone color, form, and rhythm. However, even during the revolutionary Romantic period in music. the compositions which did not have a pre-defined format (character pieces, etc) were often comfortably framed and limited within the recognizable boundaries provided by the Classical sonata style. The sonata format, when used as a tool in musical composition, provides logical boundaries that may serve to organize any unexpected emotional expressions on the part of the composer. Yet the sonata framework is also flexible enough to allow freedom of expression. In the Romantic period and beyond, composers had relied, some more than others, upon the sonata's adaptable blend of stability and flexibility. In my opinion, it is more persuasive to express oneself musically within the framework of an established musical style. Thus, I have chosen my dissertation topic as the performance of six pieces incorporating elements of the reliable and flexible sonata style. The sonata of each composer that I have selected clearly demonstrates a tension between logic and emotion expressed within the sonata framework. However, the compositions can be divided interestingly into two groups, such as 'conservative' and 'progressive' group. The 'conservative' group consists of composers who seemed to strive for greater freedom of self-expression within the constraints of the traditional sonata form. On the other hand, the 'progressive' group consists of composers who seemed more to rely upon the sonata form to rein in and add stability to their highly individual and emotional musical ideas. It is my hope that this project will provide a stimulating viewpoint from which to consider the evolution and utilization of the sonata style especially as it is applied to the composition and performance of these six diverse and interesting pieces.

Stereocomplexes Formed From Select Oligomers of Polymer d-lactic Acid (PDLA) and l-lactate May Inhibit Growth of Cancer Cells and Help Diagnose Aggressive Cancers-Applications of the Warburg Effect.

It is proposed that select oligomers of polymer d-lactic acid (PDLA) will form a stereocomplex with l-lactate in vivo, producing lactate deficiency in tumor cells. Those cancer cells that utilize transport of lactate to maintain electrical neutrality may cease to multiply or die because of lactate trapping, and those cancer cells that benefit from utilization of extracellular lactate may be impaired. Intracellular trapping of lactate produces a different physiology than inhibition of LDH because the cell loses the option of shuttling pyruvate to an alternative pathway to produce an anion. Conjugated with stains or fluorescent probes, PDLA oligomers may be an agent for the diagnosis of tissue lactate and possibly cell differentiation in biopsy specimens. Preliminary experimental evidence is presented confirming that PDLA in high concentrations is cytotoxic and that l-lactate forms a presumed stereocomplex with PDLA. Future work should be directed at isolation of biologically active oligomers of PDLA.

Interactions of chromatin context, binding site sequence content, and sequence evolution in stress-induced p53 occupancy and transactivation.

Cellular stresses activate the tumor suppressor p53 protein leading to selective binding to DNA response elements (REs) and gene transactivation from a large pool of potential p53 REs (p53REs). To elucidate how p53RE sequences and local chromatin context interact to affect p53 binding and gene transactivation, we mapped genome-wide binding localizations of p53 and H3K4me3 in untreated and doxorubicin (DXR)-treated human lymphoblastoid cells. We examined the relationships among p53 occupancy, gene expression, H3K4me3, chromatin accessibility (DNase 1 hypersensitivity, DHS), ENCODE chromatin states, p53RE sequence, and evolutionary conservation. We observed that the inducible expression of p53-regulated genes was associated with the steady-state chromatin status of the cell. Most highly inducible p53-regulated genes were suppressed at baseline and marked by repressive histone modifications or displayed CTCF binding. Comparison of p53RE sequences residing in different chromatin contexts demonstrated that weaker p53REs resided in open promoters, while stronger p53REs were located within enhancers and repressed chromatin. p53 occupancy was strongly correlated with similarity of the target DNA sequences to the p53RE consensus, but surprisingly, inversely correlated with pre-existing nucleosome accessibility (DHS) and evolutionary conservation at the p53RE. Occupancy by p53 of REs that overlapped transposable element (TE) repeats was significantly higher (p<10-7) and correlated with stronger p53RE sequences (p<10-110) relative to nonTE-associated p53REs, particularly for MLT1H, LTR10B, and Mer61 TEs. However, binding at these elements was generally not associated with transactivation of adjacent genes. Occupied p53REs located in L2-like TEs were unique in displaying highly negative PhyloP scores (predicted fast-evolving) and being associated with altered H3K4me3 and DHS levels. These results underscore the systematic interaction between chromatin status and p53RE context in the induced transactivation response. This p53 regulated response appears to have been tuned via evolutionary processes that may have led to repression and/or utilization of p53REs originating from primate-specific transposon elements.

Exploring strategies for promoting the use of research findings in practice

Following the integration of nurse and midwifery education into institutions of higher education in the United Kingdom, a number of studies have shown that a defined clinical framework for nursing and midwifery lecturers in practice areas is lacking. The aim of this study was to explore strategies that nurse and midwifery lecturers from one higher education institution in south east England can use to work collaboratively with nurses and midwives to promote the utilization of research findings in practice. A cross-sectional survey using a structured questionnaire was sent to a sample of 60 nurse and midwifery lecturers and 90 clinical managers. Response rates of 67% (40) and 69% (62) respectively were obtained. The main strategies suggested were to make clinical staff more aware of what research exist in their specialties; to help them to access research information from research databases; and to critically appraise this information. Other strategies were for teachers to run research workshops on site; to undertake joint research projects with clinical staff; to set up journal clubs or research interest groups; and to help formulate clinical guidelines and protocols which are explicitly research-based.

Exploring strategies for promoting the use of research findings in practice

Following the integration of nurse and midwifery education into institutions of higher education in the United Kingdom, a number of studies have shown that a defined clinical framework for nursing and midwifery lecturers in practice areas is lacking. The aim of this study was to explore strategies that nurse and midwifery lecturers from one higher education institution in south east England can use to work collaboratively with nurses and midwives to promote the utilization of research findings in practice. A cross-sectional survey using a structured questionnaire was sent to a sample of 60 nurse and midwifery lecturers and 90 clinical managers. Response rates of 67% (40) and 69% (62) respectively were obtained. The main strategies suggested were to make clinical staff more aware of what research exist in their specialties; to help them to access research information from research databases; and to critically appraise this information. Other strategies were for teachers to run research workshops on site; to undertake joint research projects with clinical staff; to set up journal clubs or research interest groups; and to help formulate clinical guidelines and protocols which are explicitly research-based.

Mutual information performance of differential MPSK detection over time-varying channels

This paper provides mutual information performance analysis of multiple-symbol differential WSK (M-phase shift keying) over time-correlated, time-varying flat-fading communication channels. A state space approach is used to model time correlation of time varying channel phase. This approach captures the dynamics of time correlated, time-varying channels and enables exploitation of the forward-backward algorithm for mutual information performance analysis. It is shown that the differential decoding implicitly uses a sequence of innovations of the channel process time correlation and this sequence is essentially uncorrelated. It enables utilization of multiple-symbol differential detection, as a form of block-by-block maximum likelihood sequence detection for capacity achieving mutual information performance. It is shown that multiple-symbol differential ML detection of BPSK and QPSK practically achieves the channel information capacity with observation times only on the order of a few symbol intervals

Experiences during three generations of web based learning. Six years of web based communication

This paper tells the story of how a set of university lectures developed during the last six years. The idea is to show how (1) content, (2) communication and (3) assessment have evolved in steps which are named “generations of web learning”. The reader is offered a stepwise description of both didactic foundations of university lectures and practical implementation on a widely available web platform. The relative weight of directive elements has gradually decreased through the “three generations”, whereas characteristics of self-responsibility and self-guided learning have gained in importance. -Content was in early times presented and expected to be learned but in later phases expected to be constructed for examples of case studies. -Communication meant in early phases to deliver assignments to the lecturer but later on to form teams, exchange standpoints and review mutually. -Assessment initially consisted in marks invented and added up by the lecturer but was later enriched by peer review, mutual grading and voting procedures. How much “added value” can the web provide for teaching, training and learning? Six years of experience suggest: mainly insofar as new (collaborative and selfdirected) didactic scenarios are implemented! (DIPF/Orig.)

Responses Of Mytilus-Edulis On Exposure To The Water-Accommodated Fraction Of North-Sea-Oil

Individuals of Mytilus edulis L., collected from the Erme estuary (S.W. England) in 1978, were exposed to low concentrations (7 to 68 μg l-1) of the water-accommodated fraction (WAF) of North Sea crude oil. The pattern of accumulation of petroleum hydrocarbons in the body tissues was affected by the presence of algal food cells, the period of exposure, the hydrocarbon concentration in seawater, the type of body tissue and the nature of the hydrocarbon. Many physiological responses (e.g. rates of oxygen consumption, feeding, excretion, and scope for growth), cellular responses (e.g. lysosomal latency and digestive cell size) and biochemical responses (e.g. specific activities of several enzymes) were significantly altered by short-term (4 wk) and/or long-term (5 mo) exposure to WAF. Stress indices such as scope for growth and lysosomal latency were negatively correlated with tissue aromatic hydrocarbons.

Measurement Of The Responses Of Individuals To Environmental-Stress And Pollution - Studies With Bivalve Mollusks

Certain physiological differences between individuals in different populations of the mussel, Mytilus edulis, are described. In particular, the scope for growth differs in space and time and may be used to assess the animals' physiological condition. When the required measurements are made in the field, the rates of growth predicted from the physiological data agree well with observed rates of growth. An alternative approach utilizes mussels transplanted to various waters, with indices of condition then measured in the laboratory under standard conditions; an example of this approach is illustrated. Laboratory experiments are used to equate various levels of physiological condition with fecundity, in an attempt to equate physiological effects on the individual with likely population damage. A cytochemical index of stress is described, based on the latency of lysosomal enzymes; spatial variability in this index, and its relation with the scope for growth, are discussed. Finally, the results of some experiments on the effects of petroleum hydrocarbons on mussels are described and the presence of inducible activity of NADPH-dependent tetrazolium reductase in the blood cells is demonstrated. Certain considerations that apply in adopting similar measurements of biological effects of pollution in environmental monitoring programmes are discussed.

HOME-BASED REHABILITATION AND ITS IMPACT ON HOSPITAL UTILIZATION

There is compelling evidence for the effectiveness of home-based occupational therapy and physiotherapy rehabilitation for community dwelling elderly who may struggle with basic activities and the functions of daily living and mobility. Nonetheless, an estimated 2% of home care’s elderly clients receive these therapies. Ontario’s home care data indicates that 78% of clients that could benefit from these specific therapies are not receiving them. The study examined a subset of elderly clients receiving home care following a hospital discharge during 2009-2010. The aim of this study was to: understand the difference between those home care clients who received occupational therapy or physiotherapy and those who did not; and determine if receiving these therapies impacted the utilization of hospital emergency departments and inpatient admissions. A retrospective cohort design and multivariate and survival analysis of hospital and home care administrative data structured the study. Results suggest that home-based rehabilitation is offered to a minority of the home care population. Distinct client characteristics and process variables significantly associated with the increased likelihood of receiving home-based occupational and physical therapies included: clients who were older, females, admitted to home care from hospital inpatient units, assessed as non-acute for clinical and service needs and required more home making support and assistance with activities of daily living. Almost one quarter of the total sample returned to hospital. Visits to emergency departments accounted for the greater part of hospital utilization and primarily for sub-acute general symptoms and signs, post-procedural complications, infections or acute episodes from chronic obstructive pulmonary disease and renal failure. Slightly over half of the clients returning to hospital did not receive home-based rehabilitation. Clients who received occupational therapy returned to the hospital sooner following their home care admission whereas clients receiving physiotherapy spent the longest time before rehospitalizing. The majority of the clients receiving occupational therapy were admitted to home care having just resolved sub-acute conditions or symptoms, many of which are known to influence functional and physical decline. Moreover, analysis of process variables indicated that the wait time for a referral to occupational therapy was two times longer compared to physiotherapy. These same clients also waited, on average, over one month before an occupational therapist’s first visit. The need to discriminate who receives home-based rehabilitation is essential to understanding how specific therapies contribute to improving systems outcomes. This study is the first examination that focuses specifically on home-based occupational therapy and physiotherapy rehabilitation and the client characteristics and process variables associated with receiving/not receiving these therapies and the impact these factors have on the time-to-rehospitalization.

Strategies for the development of the urinary catheter.

Indwelling urinary catheters are utilized in the management of a wide range of conditions both in an acute and a chronic setting. However, utilization of this type of device is associated with a number of issues, including an increased propensity to develop bacteriuria, symptomatic infection and also encrusted deposits on the device. The development of novel biomaterials, incorporation of therapeutic agents and other strategies to minimize the issues associated with these devices are discussed in this review.

Expedited Solid-Phase Synthesis of Fluorescently Labeled and Biotinylated Aminoalkane Diphenyl Phosphonate Affinity Probes for Chymotrypsin- and Elastase-Like Serine Proteases

In this study, we report on a novel, expedited solid-phase approach for the synthesis of biotinylated and fluorescently tagged irreversible affinity based probes for the chymotrypsin and elastase-like serine proteases. The novel solid-phase biotinylation or fluorescent labeling of the aminoalkane diphenyl phosphonate warhead using commercially available Biotin-PEG-NovaTag or EDANS NovaTag resin permits rapid, facile synthesis of these reagents. We demonstrate the kinetic evaluation and utilization of a number of these irreversible inactivators for chymotrypsin-like (chymotrypsin/human cathepsin G) and elastase-like serine proteases. Encouragingly, these compounds display comparable potency against their target proteases as their N-benzyloxycarbonyl (Cbz)-protected parent compounds, from which they were derived, and function as efficient active site-directed inactivators of their target proteases. We subsequently applied the biotinylated reagents for the sensitive detection of protease species via Western blot, showing that the inactivation of the protease was specifically mediated through the active site serine. Furthermore, we also demonstrate the successful detection of serine protease species with the fluorescently labeled derivatives “in-gel”, thus avoiding the need for downstream Western blotting. Finally, we also show the utility of biotinylated and pegylated affinity probes for the isolation/enrichment of serine protease species, via capture with immobilized streptavidin, and their subsequent identification via de novo sequencing. Given their selectivity of action against the serine proteases, we believe that these reagents can be exploited for the direct, rapid, and selective identification of these enzymes from biological milieu containing multiple protease subclasses.

Potential for phosphonoacetate utilization by marine bacteria in temperate coastal waters

Phosphonates are organic compounds that contain a C-P bond and are a poorly characterized component of the marine phosphorus cycle. They may represent a potential source of bioavailable phosphorus, particularly in oligotrophic conditions. This study has investigated the distribution of the phnA gene which encodes phosphonoacetate hydrolase, the enzyme that mineralizes phosphonoacetate. Using newly designed degenerate primers targeting the phnA gene we analysed the potential for phosphonoacetate utilization in DNA and cDNA libraries constructed from a phytoplankton bloom in the Western English Channel during July 2006. Total RNA was isolated and reverse transcribed and phosphonoacetate hydrolase (phnA) transcripts were PCR amplified from the cDNA with the degenerate primers, cloned and sequenced. Phylogenetic analysis demonstrated considerable diversity with 14 sequence types yielding five unique phnA protein groups. We also identified 28 phnA homologues in a 454-pyrosequencing metagenomic and metatranscriptomic study from a coastal marine mesocosm, indicating that > 3% of marine bacteria in this study contained phnA. phnA homologues were also present in a metagenomic fosmid library from this experiment. Finally, cultures of four isolates of potential coral pathogens belonging to the Vibrionaceae contained the phnA gene. In the laboratory, these isolates were able to grow with phosphonoacetate as sole P and C source. The fact that the capacity to utilize phosphonoacetate was evident in each of the three coastal environments suggests the potential for widespread utilization of this bioavailable P source.