Ultimate and practical limits of fluid-based mass detection with suspended microchannel resonators

Suspended microchannel resonators (SMRs) are an innovative approach to fluid-based microelectromechanical mass sensing that circumvents complete immersion of the sensor. By embedding the fluidics within the device itself, vacuum-based operation of the resonator becomes possible. This enables frequency shift-based mass detection with high quality factors, and hence sensitivity comparable to vacuum-based micromechanical resonators. Here we present a detailed analysis of the sensitivity of these devices, including consideration of fundamental and practical noise limits, and the important role of binding kinetics in sensing.We demonstrate that these devices show significant promise for protein detection. For larger, biologically-important targets such as rare whole virions, the required analysis time to flow sufficient sample through the sensor can become prohibitively long unless large parallel arrays of sensors or preconcentrators are employed

Beyond the call of duty: is there a difference in motivation of staff in profit and nonprofit organizations in Bosnia and Herzegovina?

"This paper looks at the conditions that influence employee motivation at the organizational and individual level in profit and nonprofit organizations. The large presence of international organizations in Bosnia and Herzegovina (BiH) offered a unique opportunity to test the hypothesis that profit organizations have more sophisticated human resource (HR) systems than nonprofit organizations, which could not be confirmed. At the level of individual motivation factors the paper found differences but also some consistencies between individual motivation factors for staff of both organizations. To contribute to an under-researched area the paper further looked into differences in individual motivation factors of national and international staff in a nonprofit organization. The findings confirm differences based on origin. The results of the study have practical implications for HR managers in nonprofit organizations since the paper highlights possibilities how to use the HR system to improve employee motivation." (author's abstract

Identifying primary, secondary and tertiary blast force skeletal trauma patterns for forensic recovery applications

Blast injuries are more commonplace today than in the past, due to the current sociopolitical climate and tactical mode of modern warfare. Yet, skeletal blast trauma has not been well researched, and forensic anthropology literature regarding blast trauma is sparse. Skeletal trauma and identifying the corresponding mechanism is a quintessential aspect of forensic anthropology. Blast trauma is distinguished into four categories: primary, secondary, tertiary and quaternary, based on blast’s impact on the body and the mechanism by which trauma is sustained such as contact with the blast wave. These levels and severity are dependent upon variables including distance from the explosive, type of explosive and crowding of people or objects and enclosure of the blast site. Primary blast trauma is caused by contact with the explosive blast wave, secondary is associated with the penetration of fragments from the explosive like shrapnel and tertiary is caused by contact with the blast wind which often results in bodily displacement. This study aims to expand the literature that exists for skeletal trauma and anthropology, by examining and identifying patterns at the primary, secondary and tertiary mechanism levels of skeletal blast trauma, as well as the post-blast dispersion pattern. The experimental specimens consisted of ten clothed whole domesticated pigs (Sus scrofa) to serve as proxy for humans and two different explosive attack scenarios were utilized. The first was a standalone improvised explosive device, IED, attack and the second was modeled after a suicide bomber scenario fitted with shrapnel. Additionally, three specimens were fitted with Kevlar®️ vests to examine trauma pattern differences and amount of skeletal trauma between specimens. Both scenarios were carried out with associated furniture and constructed wooden enclosure on an explosive testing range to recreate a semi-enclosed crowded city environment, which is a common target of terrorist attacks. Following the blasts, a forensic recovery team assisted with the recovery and mapping of remains. It was hypothesized that the aforementioned three levels of blast force trauma would have distinct trauma patterns which could then be applied in forensic analyses of human remains found at blast sites as well as recreating the scene pre-blast. Different patterns of trauma corresponding to mechanism levels were indeed observed, as well as an increase in trauma among the pigs fitted with Kevlar vests, especially of the vertebral column; 61 elements from vested pigs sustained fractures while only 45 elements of non-vested pigs sustained fractures. Observed primary trauma included comminuted, oblique and spiral fractures in the long bones, diastatic fractures of the cervical vertebrae and rib fractures. Secondary trauma consisted of ballistic trauma and pelvic fractures. Tertiary trauma included oblique, comminuted and linear fractures in various elements; the most frequently fractured elements were the ribs and vertebrae. All vested pigs presented ballistic trauma, as well as the most vertebral fractures overall, especially in the lower thoracic and lower cervical vertebrae. There was a disparity in the amount of observed trauma between the two scenarios. The suicide bomber scenario presented more trauma with 8.18% of all elements fractured, while only 1.23% of elements were fractured in the IED scenario. The mapping of the scene provided a new insight observed in both scenarios in the processing of a blast site which could help in reducing the duration of recovery while maximizing the yield of recovery. 85% of all debris and remains were found behind the seat of the blast rather than in front, which is what is typically expected. The observed trauma, especially in the vested pigs, furthers the current understanding of the biomechanics of blast trauma fractures and injuries

Rubble & Honey

RUBBLE & HONEY is a collection of poems unified by its use of language driven lyricism to recount personal narratives in the life of the poet. The poems in this manuscript depict the landscapes of California, Florida, Mississippi, the South Downs of England, and Anglesey off the northwest coast of Wales. The manuscript engages with these physical spaces, how the speaker reacts to the natural world and how these locations can reflect the internal. The collection is broken into four sections: the first two explore parting, firstly from a relationship and then revisiting the poet’s childhood landscape of Sussex, England; the third is a rebirth of sorts after the exploration of these losses, a joyous look at the world that is tentative but hopeful; and the fourth section revisits the themes of the first from a more distanced perspective

Prolonged expression of the γ-H2AX DNA repair biomarker correlates with excess acute and chronic toxicity from radiotherapy treatment

The normal tissue tolerance levels to fractionated radiotherapy have been appreciated by a century of careful clinical observations and radiobiological studies in animals. During clinical fractionated radiotherapy, these normal tissue tolerance levels are respected, and severe sequelae of radiotherapy are avoided in the majority of patients. Notwithstanding, a minority of patients experience unexpectedly severe normal tissue reactions. The ability to predict which patients might form this minority would be important. We have conducted a study to develop a rapid and reliable diagnostic test to predict excessive normal tissue toxicity (NTT) in radiotherapy patients. A flow cytometric immunocytochemical assay was used to measure DNA damage in peripheral blood lymphocytes (PBL) from cancer patients exposed to 2-Gy gamma radiation. DNA damage and repair was measured by induction of cellular γ-H2AX in unirradiated and exposed cells at specific time points following exposure. In 12 cancer patients that experienced severe atypical NTT following radiotherapy, there was a failure to repair DNA double-strand breaks (DSB) as measured by γ-H2AX induction and persistence. In ten cancer patients that experienced little or no NTT and in seven normal (noncancer controls), efficient repair of DNA DSB was observed in the γ-H2AX assay. We conclude that a flow cytometric assay based on γ-H2AX induction in PBL of radiotherapy patients may represent a robust, rapid and reliable biomarker to predict NTT during radiotherapy. Further research is required with a larger patient cohort to validate this important study

Elevated expression of artemis in human fibroblast cells is associated with cellular radiosensitivity and increased apoptosis

Copyright @ 2012 Nature Publishing GroupThis article has been made available through the Brunel Open Access Publishing Fund.Background: The objective of this study was to determine the molecular mechanism(s) responsible for cellular radiosensitivity in two human fibroblast cell lines 84BR and 175BR derived from two cancer patients. Methods: Clonogenic assays were performed following exposure to increasing doses of gamma radiation to confirm radiosensitivity. γ-H2AX foci assays were used to determine the efficiency of DNA double strand break (DSB) repair in cells. Quantitative-PCR (Q-PCR) established the expression levels of key DNA DSB repair proteins. Imaging flow cytometry using Annexin V-FITC was used to compare artemis expression and apoptosis in cells. Results: Clonogenic cellular hypersensitivity in the 84BR and 175BR cell lines was associated with a defect in DNA DSB repair measured by the γ-H2AX foci assay. Q-PCR analysis and imaging flow cytometry revealed a two-fold overexpression of the artemis DNA repair gene which was associated with an increased level of apoptosis in the cells before and after radiation exposure. Over-expression of normal artemis protein in a normal immortalised fibroblast cell line NB1-Tert resulted in increased radiosensitivity and apoptosis. Conclusion: We conclude elevated expression of artemis is associated with higher levels of DNA DSB, radiosensitivity and elevated apoptosis in two radio-hypersensitive cell lines. These data reveal a potentially novel mechanism responsible for radiosensitivity and show that increased artemis expression in cells can result in either radiation resistance or enhanced sensitivity.This work was supported in part by The Vidal Sassoon Foundation USA. This article is made available through the Brunel Open Access Publishing Fund

A semi-automated non-radiactive system for measuring recovery of RNA synthesis and unscheduled DNA synthesis using ethynyluracil derivatives

Nucleotide excision repair (NER) removes the major UV-photolesions from cellular DNA. In humans, compromised NER activity is the cause of several photosensitive diseases, one of which is the skin-cancer predisposition disorder, xeroderma pigmentosum (XP). Two assays commonly used in measurement of NER activity are ‘unscheduled DNA synthesis (UDS)’, and ‘recovery of RNA synthesis (RRS)’, the latter being a specific measure of the transcription-coupled repair sub-pathway of NER. Both assays are key techniques for research in NER as well as in diagnoses of NER-related disorders. Until very recently, reliable methods for these assays involved measurements of incorporation of radio-labeled nucleosides. We have established non-radioactive procedures for determining UDS and RRS levels by incorporation of recently developed alkyne-conjugated nucleoside analogues, 5-ethynyl-2′-deoxyuridine (EdU) and 5-ethynyuridine (EU). EdU and EU are respectively used as alternatives for 3H-thymidine in UDS and for 3H-uridine in RRS. Based on these alkyne-nucleosides and an integrated image analyser, we have developed a semi-automated assay system for NER-activity. We demonstrate the utility of this system for NER-activity assessments of lymphoblastoid samples as well as primary fibroblasts. Potential use of the system for large-scale siRNA-screening for novel NER defects as well as for routine XP diagnosis are also considered