Exo1 plays a major role in DNA end resection in humans and influences double-strand break repair and damage signaling decisions

The resection of DNA double-strand breaks (DSBs) to generate ssDNA tails is a pivotal event in the cellular response to these breaks. In the two-step model of resection, primarily elucidated in yeast, initial resection by Mre11-CtIP is followed by extensive resection by two distinct pathways involving Exo1 or BLM/WRN-Dna2. However, resection pathways and their exact contributions in humans in vivo are not as clearly worked out as in yeast. Here, we examined the contribution of Exo1 to DNA end resection in humans in vivo in response to ionizing radiation (IR) and its relationship with other resection pathways (Mre11-CtIP or BLM/WRN). We find that Exo1 plays a predominant role in resection in human cells along with an alternate pathway dependent on WRN. While Mre11 and CtIP stimulate resection in human cells, they are not absolutely required for this process and Exo1 can function in resection even in the absence of Mre11-CtIP. Interestingly, the recruitment of Exo1 to DNA breaks appears to be inhibited by the NHEJ protein Ku80, and the higher level of resection that occurs upon siRNA-mediated depletion of Ku80 is dependent on Exo1. In addition, Exo1 may be regulated by 53BP1 and Brca1, and the restoration of resection in BRCA1-deficient cells upon depletion of 53BP1 is dependent on Exo1. Finally, we find that Exo1-mediated resection facilitates a transition from ATM- to ATR-mediated cell cycle checkpoint signaling. Our results identify Exo1 as a key mediator of DNA end resection and DSB repair and damage signaling decisions in human cells.

Power electronic converters for high power ultrasound transducers

Piezoelectric transducers convert electrical energy to mechanical energy and play a great role in ultrasound systems. Ultrasound power transducer performance is strongly related to the applied electrical excitation. To have a suitable excitation for maximum energy conversion, it is required to analyze the effects of input signal waveform, medium and input signal distortion on the characteristic of a high power ultrasound system (including ultrasound transducer). In this research, different input voltage signals are generated using a single-phase power inverter and a linear power amplifier to excite a high power ultrasound transducer in different medium (water and oil) in order to study the characteristic of the system. We have also considered and analyzed the effect of power converter output voltage distortions on the performance of the high power ultrasound transducer using a passive filter.

Personal preferences for end-of-life care among Taiwanese community city dwellers : an inductive approach for qualitative data

Background: As an increasing number of Taiwanese people live out the final stages of their lives with chronic and complex conditions. Care decisions at the end of life can also be complex, overwhelming and stressful for an individual, family and health professionals. Understanding individuals’ wishes for end-of-life care and factors which influence individuals' decisions is important so that the provision of quality end-of-life care for all can be promoted and ensured.

Growing profitable or growing from profits : putting the horse in front of the cart?

Top lists of and praise for the economy's fastest growing firms abound in business media around the world. Similarly, in academic research there has been a tendency to equate firm growth with business success. This tendency appears to be particularly pronounced in-but not confined to­ entrepreneurship research. In this study we critically examine this tendency to portray firm growth as more or less universally favorable. While several theories suggest that growth drives profitability we first show that the available empirical evidence does not support the existence of a general, positive relation­ ship between growth and profitability. Using the theoretical lens of the Resource-Based View (RBV) we then argue that sound growth usually starts with achieving sufficient levels of profitability. In summary, our theoretical argument is as follows: In a population of SMEs, superior profitability is likely to be indicative of having built a resource-based competitive advantage. Building such a valuable and hard to-copy advantage may at first constrain growth. However, the underlying advantage itself and the financial resources generated through high profitability make it possible for firms in this situation to now achieve sound and sustainable growth - which may require building a series of temporary advantages- without having to sacrifice profitability. By contrast, when firms strive for high growth starting from low profitability, the latter often indicates lack of competitive advantage. Therefore growth must be achieved in head-to-head competition with equally attractive alternatives, leading to profitability deterioration rather than improvement. In addition, these low profitability firms are unlikely to be able to finance strategies toward building valuable and difficult-to-imitate advantages while growing.

Water end use consumption analysis study into Gold Coast dual reticulated households : pilot study

Australia is the driest inhabited continent in the world and persisting droughts have triggered a move toward sensible and sustainable water consumption. Understanding how and where water is consumed in households enables streamlined development of demand management programs and efficient engineering of water infrastructure. End use water consumption analysis is required to gain necessary empirical data of how and where water is consumed. Several end use water consumption studies have been conducted within Australia and around the world with varying results produced. This pilot study paper provides preliminary data from the Gold Coast Watersaver End Use Project which is currently underway. Specifically, the paper includes water end use category volumetric and percentage break downs for 18 single and 32 dual reticulated homes on the Gold Coast (i.e. 50 in total). Moreover, a comparitive analysis between each of the individual households water end use levels is discussed along with other national studies previously completed. The paper finishes with an overview of the greater 200 home end use study conducted on the Gold Coast and its key deliverables and research outcomes.

Editor 3.0: Redesigining the YAWL user interface

It has long been a concern that the wider uptake of the YAWL environment may have been hindered by the usability issues identified in the current Process Editor. As a consequence, it was decided that the Editor be completely rewritten to address those usability limitations. The result has been the implementation of a new YAWL Process Editor architecture that creates a clear separation between the User Interface component layer and the core processing back end, facilitating the redesign of the default user interface. This new architecture also supports the development of multiple User Interface front ends for specific contexts that take advantage of the core capabilities the new Editor architecture has to offer.

Power converters design and analysis for high power piezoelectric ultrasonic transducers

High power piezoelectric ultrasonic transducers have been widely exploited in a variety of applications. The critical behaviour of a piezoelectric device is encapsulated in its resonant frequencies because of its maximum transmission performance at these frequencies. Therefore power electronic converters should be tuned at those resonant frequencies to transfer electrical power to mechanical power efficiently. However, structural and environmental changes cause variations in the device resonant frequencies which can degrade the system performance. Hence, estimating the device resonant frequencies within the incorporated setup can significantly improve the system performance. This paper proposes an efficient resonant frequency estimation approach to maintain the performance of high power ultrasonic applications using the employed power converter. Experimental validations indicate the effectiveness of the proposed method.

New labour and the environment : too little too late.

New Labour and the environment: too little too late – symbolic success but real failure Achievements: Introduction of the Climate Change Act 2008, Low Carbon Transition Plan, the creation of the Department of Energy and Climate Change, establishment of several ‘green’ quangos and Green Investment Bank, Warm Front Scheme, international leadership on Kyoto and the European Directive for Landfill and Renewable Energy. Disappointments: Increased green house gas emissions that failto meet domestic UK targets, let alone Kyoto; significant increasesin energy and transport emissions; EU air pollution violations; failure to regulate the importation of illegally logged timber and wildlife; increase in chemical agriculture; unwillingness to tackle corporate environmental crime; road expansions and runway projects at the expense of low emission alternative public transport. Biggest broken promises: Global warming, low carbon transport; protection of biodiversity.

Teaching end-user remote online searching

The Queensland University of Technology (QUT) Library bas recently commenced teaching higher degree students to search online systems such as BRS, ORBIT and STN. The emphasis is on education rather than training. with students being required to familiarise themselves with system commands and database structures whilst receiving necessarily limited tutorial help. The teaching strategies used and problems encountered in the program are outlined. Student responses to the experience of learning to online search are discussed.

Towards better end-of-life care : a major opportunity for nurses to contribute to the debate

Integrated care pathways are documents which outline the essential steps of multidisciplinary care in addressing a specific clinical problem (Rotter et al., 2010). They can be used to introduce clinical guidelines and systematic audits of clinical practice, and to ensure that the most appropriate management occurs at the most appropriate time and that it is provided by the most appropriate health professional. The Liverpool Care Pathway (LCP) is an example of an integrated care pathway, designed in the 1990s to guide care for people who are in their last days of life (Ellershaw et al., 1997, Ellershaw and Ward, 2003)...

High frequency high power converters for industrial applications

The main contribution of this project was to investigate power electronics technology in designing and developing high frequency high power converters for industrial applications. Therefore, the research was conducted at two levels; first at system level which mainly encapsulated the circuit topology and control scheme and second at application level which involves with real-world applications. Pursuing these objectives, varied topologies have been developed and proposed within this research. The main aim was to resolving solid-state switches limited power rating and operating speed while increasing the system flexibility considering the application characteristics. The developed new power converter configurations were applied to pulsed power and high power ultrasound applications for experimental validation.

Self management of haemodialysis for end stage renal disease : a systematic review

Background Exploring self management in End Stage Renal Disease is extremely important for patients as they encounter several challenges including ongoing symptoms, complex treatments and restrictions, uncertainty about life and a dependency on technology, all of which impact upon their autonomy particularly after commencement of haemodialysis. Objective To summarise the effects of nursing interventions which effect selfmanagement of haemodialysis for patients with End Stage Renal Disease. Search strategy Search terms were chosen after reviewing text words and MeSH terms in relevant articles and databases. An extensive search of the literature from 1966 to June 2009 was conducted across a range of health databases including Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, PsycINFO and Web of Science. Further studies were identified from reference lists of all retrieved studies. Selection criteria We considered randomised controlled trials that compared interventions to improve self management of haemodialysis in patients with ESRD. In the absence of RCTs, comparative studies without randomisation as well as before and after studies were considered for inclusion. Methodological quality Study reports selected for retrieval were assessed by two independent reviewers for methodological quality prior to inclusion in the review using the standardised critical appraisal instruments for the Joanna Briggs Institute System for the Unified Management, Assessment and Review of Information package (SUMARI). Data collection and analysis Data was extracted using the JBI data extraction tool for evidence of effectiveness independently by pairs of review authors. The evidence was reported in narrative summaries due to heterogeneity of the interventions of the studies. Results and conclusions Five randomised controlled trials were included in the review. Overall, the evidence found that psychosocial and educational interventions influenced self management of haemodialysis in this patient population.

Applications and equivalent models for coupled inductor parallel interleaved converters

Parallel interleaved converters are finding more applications everyday, for example they are frequently used for VRMs on PC main boards mainly to obtain better transient response. Parallel interleaved converters can have their inductances uncoupled, directly coupled or inversely coupled, all of which have different applications with associated advantages and disadvantages. Coupled systems offer more control over converter features, such as ripple currents, inductance volume and transient response. To be able to gain an intuitive understanding of which type of parallel interleaved converter, what amount of coupling, what number of levels and how much inductance should be used for different applications a simple equivalent model is needed. As all phases of an interleaved converter are supposed to be identical, the equivalent model is nothing more than a separate inductance which is common to all phases. Without utilising this simplification the design of a coupled system is quite daunting. Being able to design a coupled system involves solving and understanding the RMS currents of the input, individual phase (or cell) and output. A procedure using this equivalent model and a small amount of modulo arithmetic is detailed.