451 research outputs found
Bifocal contact lenses: A review
A review of bifocal contact lenses has been formulated to introduce the reader to research in this area. Published literature and clinical use are incorporated into a tangible model that will allow a practitioner to understand the lens contructs, optics, and successful fitting methods. The article also contains a simplified fitting guide that can aid in the fitting of bifocal contact lenses. Some complications that commonly occur with these lenses, lens candidates, and special fitting applications are explored and fitting solutions identified. The guide can be utilized as an educational model to help incorporate bifocal contact lenses into a practice
Intern Self-Care: An Exploratory Study Into Strategy Use and Effectiveness
In this exploratory study, 363 interns were surveyed to assess the frequency of use and effectiveness of self-care strategies used during the internship year. Among the most frequently used strategies were family and friend social support, active problem solving, and humor. The most effective strategies were family and friend social support, seeking pleasurable experiences, and humor. A strong positive relationship was found between total scores for Frequency and Effectiveness subscales, and women reported significantly more use and effectiveness of strategies. Recommendations and resources are provided for interns and internship sites that seek to further understand and encourage intern self-care
ADAPTABILITY OF VIETNAMESE SMEs TOWARD OUTSOURCING TREND
This article is to determine the adaptability of Vietnamese SMEs (small and toward international outsourcing trend. Organizations in developed countries usually find some less developed countries within which they may outsourceoperations. Outsourcing has become an effective good way for companies to increase profits by reducing production costs. This is attractive to less developed and developing countries as it encourages economic growth. However, to become an attractive destination of outsourcers, these developing countries need to possess high level human resources, attractive policies and business climate in conjunction with excellent infrastructure but low operation costs. Vietnamese SMEs only focus on labor-based outsourcing services which can bring about much lower benefits than aknowledge based services. A survey was done to get the viewpoints of Vietnamese SMEs’ managers about outsourcing requirements. After that we use the zero-sum method to determine which factors Vietnamese SMEs’ managers think the outsourcers should consider the most important when seeking outsource destination. Beside, we also base on background knowledge to understand Vietnamese SMEs’ entrepreneurship basing on this aspect. The result shows that Vietnamese SMEs think costs, especially labor costs, operation costs and administration costs are most important elements encourage outsourcers choose an outsourcing place
INTELLIGENT RESOURCE DISCOVERY USING ONTOLOGYBASED RESOURCE PROFILES
Successful resource discovery across heterogeneous repositories is highly dependent on the semantic and syntactic homogeneity of the associated resource descriptions in each repository. Ideally, consistent resource descriptions are easily extracted from each repository, expressed using standard syntactic and semantic structures, and managed and accessed within a distributed, flexible, and scalable software framework. In practice however, seldom do all three of these elements exist. To help address this situation, the Object Oriented Data Technology (OODT) project at the Jet Propulsion Laboratory has developed an extensible, standards-based resource description scheme that provides the necessary description and management facilities for the discovery of resources across heterogeneous repositories. The OODT resource description scheme can be used across scientific domains to describe any resource. It uses a small set of generally accepted, broadly-scoped descriptors while also providing a mechanism for the inclusion of domain-specific descriptors. In addition, the OODT scheme can be used to capture hierarchical, relational and recursive relationships between resources. In this paper we expand on prior work and describe an intelligent resource discovery framework that consists of separate software and data architectures focusing on the standard resource description scheme. We illustrate intelligent resource discovery using a case study that provides efficient search across distributed repositories using common interfaces and a hierarchy of resource descriptions derived from a complex, domain-specific ontology
Nanoporous alumina templates : anodisation and mechanical characterisation
Due to applications in electronics, optoelectronics, energy storage,
photocatalysis, photonics and biosensors/biomaterials, interest in onedimensional
nanostructures has grown significantly during the last decade.
The use of nanoporous templates as matrices for fabrication of
nanostructures is now commonplace in microelectronics technology. Studies
on semiconductors and dielectrics have introduced nanoporous anodised
aluminium oxide as a very promising template material for the deposition
of nanostructures. It is formed of an array of closely packed hexagonal oxide
cells, in the centre of each of which there is a vertical hollow channel,
fabricated by simple electrochemical anodisation. Anodisation, an
economically viable electrochemical process, has been extensively
investigated over a number of years to obtain protective and decorative films
on an Al surface. The advantages in using these templates are controllability
of the pore size, ratio aspect and use of low cost and simple equipment.
Nanoindentation, a method that makes use of very low loads in the millinewton
range has been widely used for measuring mechanical properties
such as the hardness and Young’s modulus of test samples. In the first part
of this chapter, the anodisation of alumina templates, as well as the
electrochemical process parameters and mechanisms are discussed by means
of structural and morphological characterisation. The second part is
dedicated to the study of mechanical properties of nanotemplates using
nanoindentation.Fundação para a Ciência e
Tecnologia and FP7-PEOPLE-2010-IRSES-NanoCIS (269279) project
Electrochemical anodizing, structural and mechanical characterization of nanoporous alumina templates
Highly ordered Anodic Aluminum Oxide (AAO) structures produced from aluminum by
using an electrochemical anodizing method were developed towards its application for the next
generation of micro/nano medical and energy devices. In addition of analyzing the anodizing
current profile, the surface morphology was characterized by using Scanning Electron Microscopy
(SEM), the crystalline structure by X-Ray Diffraction (XRD) and the mechanical properties by
nanoindentation experiments. The anodizing time and applied potential determines the nanopores
regularity and their size, although the effect of the potential is more pronounced than the effect of
temperature in the transformation from crystalline alumina to amorphous alumina. Optimum pore
growth was achieved with an applied potential of 17 V which led to a pore fraction - P(f) - of about
17.5%. The experimental Berkovich nanoindentation method was used to determine the AAO
hardness as a function of the indenter depth, during the loading stage, using mechanical response
and deformation behaviour of the nanopores structure. From the experimental data of the loaddisplacement
curves, this method allows the calculation of the indenter contact depth at each
reloading point, thus leading to the estimation of the material’s hardness. The results reveal that the
hardness depends on the processing conditions used for the production of the AAO samples that
also strongly influences the organization and pore size uniformity.FCT (Fundação para a Ciência e Tecnologia) for funding through Ciencia 2007 programme and the pluriannual contract with CFUM
Preclinical efficacy of hK2 targeted [177Lu]hu11B6 for prostate cancer theranostics
Androgen ablating drugs increase life expectancy in men with metastatic prostate cancer, but resistance inevitably develops. In a majority of these recurrent tumors, the androgen axis is reactivated in the form of increased androgen receptor (AR) expression. Targeting proteins that are expressed as a down-stream effect of AR activity is a promising rationale for management of this disease. The humanized IgG1 antibody hu11B6 internalizes into prostate and prostate cancer (PCa) cells by binding to the catalytic cleft of human kallikrein 2 (hK2), a prostate specific enzyme governed by the AR-pathway. In a previous study, hu11B6 conjugated with Actinium-225 (225Ac), a high linear energy transfer (LET) radionuclide, was shown to generate an AR-upregulation driven feed-forward mechanism that is believed to enhance therapeutic efficacy. We assessed the efficacy of hu11B6 labeled with a low LET beta-emitter, Lutetium-177 (177Lu) and investigated whether similar tumor killing and AR-enhancement is produced. Moreover, single-photon emission computed tomography (SPECT) imaging of 177Lu is quantitatively accurate and can be used to perform treatment planning. [177Lu]hu11B6 therefore has significant potential as a theranostic agent. Materials and Methods: Subcutaneous PCa xenografts (LNCaP s.c.) were grown in male mice. Biokinetics at 4-336 h post injection and uptake as a function of the amount of hu11B6 injected at 72 h were studied. Over a 30 to 120-day treatment period the therapeutic efficacy of different activities of [177Lu]hu11B6 were assessed by volumetric tumor measurements, blood cell counts, molecular analysis of the tumor as well as SPECT/CT imaging. Organ specific mean absorbed doses were calculated, using a MIRD-scheme, based on biokinetic data and rodent specific S-factors from a modified MOBY phantom. Tumor tissues of treated xenografts were immunohistochemically (IHC) stained for Ki-67 (proliferation) and AR, SA-β-gal activity (senescence) and analyzed by digital autoradiography (DAR). Results: Organ-to-blood and tumor-to-blood ratios were independent of hu11B6 specific activity except for the highest amount of antibody (150 µg). Tumor accumulation of [177Lu]hu11B6 peaked at 168 h with a specific uptake of 29 ± 9.1 percent injected activity per gram (%IA/g) and low accumulation in normal organs except in the submandibular gland (15 ± 4.5 %IA/g), attributed to a cross-reaction with mice kallikreins in this organ, was seen. However, SPECT imaging with therapeutic amounts of [177Lu]hu11B6 revealed no peak in tumor accumulation at 7 d, probably due to cellular retention of 177Lu and decreasing tumor volumes. For [177Lu]hu11B6 treated mice, tumor decrements of up to 4/5 of the initial tumor volume and reversible myelotoxicity with a nadir at 12 d were observed after a single injection. Tumor volume reduction correlated with injected activity and the absorbed dose. IHC revealed retained expression of AR throughout treatment and that Ki-67 staining reached a nadir at 9-14 d which coincided with high SA- β-gal activity (14 d). Quantification of nuclei staining showed that Ki-67 expression correlated negatively with activity uptake. AR expression levels in cells surviving therapy compared to previous timepoints and to controls at 30 d were significantly increased (p = 0.017). Conclusions: This study shows that hu11B6 labeled with the low LET beta-emitting radionuclide 177Lu can deliver therapeutic absorbed doses to prostate cancer xenografts with transient hematological side-effects. The tumor response correlated with the absorbed dose both on a macro and a small scale dosimetric level. Analysis of AR staining showed that AR protein levels increased late in the study suggesting a therapeutic mechanism, a feed forward mechanism coupled to AR driven response to DNA damage or clonal lineage selection, similar to that reported in high LET alpha-particle therapy using 225Ac labeled hu11B6, however emerging at a later timepoint
Behavioural symptoms of mental health disorder such as depression among young people using Instagram: a systematic review.
There is a growing debate on the linkage between social networking platforms and mental health disorder, such as depressive behaviour or depression. However, the relationship between Instagram use and depression or depressive behaviour has not been exhaustively examined. This review aims to examine these two variables. Only peer-reviewed journal articles that are published between October 2010 and December 2018 were sought in central and journal databases. Studies were selected based on predefined criteria and assessed for risk of bias and quality of evidence using GRADE. 1,856 studies were the outcome of the search, out of which 9 meets all eligible criteria. Of the 9 studies, three-quarter was published between 2017 and 2018, covering five continents: (North America: 3; Asia: 2; Australia: 2; South America: 1, Europe: 1). The final included studies broadly examined young Instagram users between the age of 19 and 35. The synthesis affirmed a linkage between Instagram and symptoms of depression or depressive behaviour. Variables that moderate this relationship are social comparison, self-esteem built on validation and approval of others, social media dependence, gender, negative or insufficient feedback, poor self-rated attractiveness, Instagram broadcasting and loneliness, younger users and risk of anxiety, and the number of strangers that users follow. There is a strong relationship between Instagram use and mental health disorders such as depression or depressive behaviour; however, no in-depth direct causality is proven yet. Further studies are needed to unravel the direct causality puzzles
Hugo: A Cluster Scheduler that Efficiently Learns to Select Complementary Data-Parallel Jobs
Distributed data processing systems like MapReduce, Spark, and Flink are
popular tools for analysis of large datasets with cluster resources. Yet, users
often overprovision resources for their data processing jobs, while the
resource usage of these jobs also typically fluctuates considerably. Therefore,
multiple jobs usually get scheduled onto the same shared resources to increase
the resource utilization and throughput of clusters. However, job runtimes and
the utilization of shared resources can vary significantly depending on the
specific combinations of co-located jobs.
This paper presents Hugo, a cluster scheduler that continuously learns how
efficiently jobs share resources, considering metrics for the resource
utilization and interference among co-located jobs. The scheduler combines
offline grouping of jobs with online reinforcement learning to provide a
scheduling mechanism that efficiently generalizes from specific monitored job
combinations yet also adapts to changes in workloads. Our evaluation of a
prototype shows that the approach can reduce the runtimes of exemplary Spark
jobs on a YARN cluster by up to 12.5%, while resource utilization is increased
and waiting times can be bounded
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