Home About us Contact
|
Home About us Contact | ||
|
|
||
Useful Guide (useful + guide)
Selected AbstractsImplications of the proposed thyroid fine-needle aspiration category of "follicular lesion of undetermined significance": A five-year multi-institutional analysisDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2009Lester J. Layfield M.D. Abstract National Cancer Institute State of the Science Conference on thyroid fine-needle aspiration (FNA) summarized diagnostic terminology. Six diagnostic categories were proposed including "follicular lesion of undetermined significance" (FLUS). FLUS was defined as findings neither convincingly benign nor sufficiently atypical for a diagnosis of "follicular neoplasm" or "suspicious for malignancy." It was proposed that this category represent less than 7% of thyroid FNAs. A search of the cytology records at three University Hospitals was performed for the term FLUS or older equivalent terms. Usage of FLUS was compared between institutions and among pathologists. Surgical pathology outcome for FLUS cases was determined. Twenty-eight pathologists evaluated 6,872 cases at the three institutions. Use of FLUS varied among pathologists (2.5 to 28.6%). Frequency of use of FLUS among institutions varied from 3.3 to 14.9%. FLUS cases [127 of 673 (18.9%)] underwent surgical exploration with malignancy identified in 36 cases (28.3%) undergoing resection. Use of FLUS varied substantially among pathologists and institutions. FLUS category requires more rigorously defined morphologic criteria for it to become a useful guide in clinical management. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Transfer or adapt business practices internationally?GLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 3 2010Some answers from Southeast Asia International organizations have long been torn between transferring their existing practices into new locations or adapting to local conditions. A major miscalculation can have extremely negative consequences for companies as they expand internationally. An examination of business practices in the Theravada Buddhist countries of Southeast Asia illustrates how breaking down business practices into their strategic, tactical, and operational levels may provide a useful guide for setting up initial operations in a foreign environment. It is proposed that strategic principles can be transferred but strategic practices should adapt to local conditions; tactical-level business practices will generally need to adapt to the local environment, while it is likely that best practices at the operational level can be transferred across international borders with little need to adapt to local conditions. © 2010 Wiley Periodicals, Inc. [source] Defending the Scientific Foundations of the Firearms and Tool Mark Identification Discipline: Responding to Recent ChallengesJOURNAL OF FORENSIC SCIENCES, Issue 3 2007Ronald G. Nichols M.Ch.M. ABSTRACT: Recent challenges have brought the discipline of firearms and tool mark identification to the forefront in recent court cases. This article reviews those challenges and offers substantial support for the scientific foundations of the firearms and tool mark identification discipline. A careful review of the available literature has revealed that firearms and tool mark identification is rooted in firm scientific foundations, critically studied according to the precepts of the scientific method culminating in the Association of Firearms and Toolmark Examiners' Theory of Identification. Firearms and tool mark identification has been validated in a manner appropriate for evidence of the kind to be expected in firearms and tool mark examinations. Proficiency tests and error rates have been studied and can provide consumers of the disciple with a useful guide as to the frequency with which misidentifications are reported in the community using appropriate methodologies and controls. As a result, the primary issues in recent challenges do not invalidate the firearms and tool mark discipline as a science nor should it detract it from its admissibility in a court of law. [source] Population Genetic Structure of the Medicinal Plant Vitex rotundifolia in China: Implications for its Use and ConservationJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 9 2008Yuan Hu Abstract Vitex rotundifolia L. is an important plant species used in traditional Chinese medicine. For its efficient use and conservation, genetic diversity and clonal variation of V. rotundifolia populations in China were investigated using inter-simple sequence repeat markers. Fourteen natural populations were included to estimate genetic diversity, and a large population with 135 individuals was used to analyze clonal variation and fine-scale spatial genetic structure. The overall genetic diversity (GD) of V. rotundifolia populations in China was moderate (GD = 0.190), with about 40% within-population variation. Across all populations surveyed, the average within-population diversity was moderate (P = 22.6%; GD = 0.086). A relatively high genetic differentiation (Gst = 0.587) among populations was detected based on the analysis of molecular variance data. Such characteristics of V. rotundifolia are likely attributed to its sexual/asexual reproduction and limited gene flow. The genotypic diversity (D = 0.992) was greater than the average values of a clonal plant, indicating its significant reproduction through seedlings. Spatial autocorrelation analysis showed a clear within-population structure with gene clusters of approximately 20 m. Genetic diversity patterns of V. rotundifolia in China provide a useful guide for its efficient use and conservation by selecting particular populations displaying greater variation that may contain required medicinal compounds, and by sampling individuals in a population at >20 m spatial intervals to avoid collecting individuals with identical or similar genotypes. [source] Searching for cluster substructure using APM and ROSAT dataMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2001V. Kolokotronis We present a detailed study of the morphological features of 22 rich galaxy clusters. Our sample is constructed from a cross-correlation of optical data with X-ray (0.1,2.4 keV) ROSAT pointed observations. We systematically compare cluster images and morphological parameters in an attempt to reliably identify possible substructure in both optical and the X-ray images. To this end, we compute various moments of the optical and X-ray surface-brightness distribution such as the ellipticities, centre-of-mass shifts and ellipsoidal orientations. We assess the significance of our results using Monte Carlo simulations. We find significant correlations between the optical and X-ray morphological parameters, indicating that in both parts of the spectrum it is possible to identify correctly the dynamical state of a cluster. Most of our clusters (17/22) have a good one-to-one correspondence between the optical and the X-ray images, and about 10 appear to have strong indications of substructure. This corresponds to a minimum percentage of order ,45 per cent, which is in very good accordance with other similar analyses. Finally, five out of 22 systems (,22 per cent) seem to have distinct subclumps in the optical which are not verified in the X-ray images, and thus are suspect of being due to optical projection effects. These results will serve as a useful guide in interpreting subsequent analyses of large optical cluster catalogues. [source] APEX: A new map of the cold dust in our galaxyASTRONOMY & GEOPHYSICS, Issue 4 2009Article first published online: 20 JUL 200 An atlas of the Milky Way galaxy at submillimetre wavelengths will prove a useful guide for forthcoming science from ALMA and Herschel. [source] Methodological considerations when conducting direct observation in an outdoor environment: our experience in local parksAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2001Susanne Engelhard Objective: This paper discusses some of the inherent methodological limitations of gathering data via direct observation using local parks as a case study. Methods: Direct observation was carried out in five parks on seven non-consecutive days in 1998 and on matched days in 1999. Information recorded for each person included the time of park entry and exit, gender, age group, and activity/ies undertaken while in the park. Methodological considerations: The location of the observation point, observer reliability, recording and accuracy of data, and specific issues related to outdoor observation areas should all be considered when designing a study incorporating direct observation as a data collection method. Conclusions: Direct observation can provide valuable information. However, pilot testing is essential for minimising potential problems associated with this method and optimising data quality. Implications: The issues discussed in this paper provide a useful guide for other researchers undertaking direct observation in outdoor environments. [source] Preterm premature rupture of membranes: diagnosis, evaluation and management strategiesBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2005Hyagriv N. Simhan Preterm premature rupture of the membranes (PPROM) is responsible for one-third of all preterm births and affects 120,000 pregnancies in the United States each year. Effective treatment relies on accurate diagnosis and is gestational age dependent. The diagnosis of PPROM is made by a combination of clinical suspicion, patient history and some simple tests. PPROM is associated with significant maternal and neonatal morbidity and mortality from infection, umbilical cord compression, placental abruption and preterm birth. Subclinical intrauterine infection has been implicated as a major aetiological factor in the pathogenesis and subsequent maternal and neonatal morbidity associated with PPROM. The frequency of positive cultures obtained by transabdominal amniocentesis at the time of presentation with PPROM in the absence of labour is 25,40%. The majority of amniotic fluid infection in the setting of PPROM does not produce the signs and symptoms traditionally used as diagnostic criteria for clinical chorioamnionitis. Any evidence of infection by amniocentesis should be considered carefully as an indication for delivery. Documentation of amniotic fluid infection in women who present with PPROM enables us to triage our therapeutic decision making rationally. In PPROM, the optimal interval for delivery occurs when the risks of immaturity are outweighed by the risks of pregnancy prolongation (infection, abruption and cord accident). Lung maturity assessment may be a useful guide when planning delivery in the 32- to 34-week interval. A gestational age approach to therapy is important and should be adjusted for each hospital's neonatal intensive care unit. Antenatal antibiotics and corticosteroid therapies have clear benefits and should be offered to all women without contraindications. During conservative management, women should be monitored closely for placental abruption, infection, labour and a non-reassuring fetal status. Women with PPROM after 32 weeks of gestation should be considered for delivery, and after 34 weeks the benefits of delivery clearly outweigh the risks. [source] Addressing the Numbers Problem in Directed EvolutionCHEMBIOCHEM, Issue 11 2008Manfred T. Reetz Prof. Dr. Abstract Our previous contribution to increasing the efficiency of directed evolution is iterative saturation mutagenesis (ISM) as a systematic means of generating focused libraries for the control of substrate acceptance, enantioselectivity, or thermostability of enzymes. We have now introduced a crucial element to knowledge-guided targeted mutagenesis in general that helps to solve the numbers problem in directed evolution. We show that the choice of the amino acid (aa) alphabet, as specified by the utilized codon degeneracy, provides the experimenter with a powerful tool in designing "smarter" randomized libraries that require considerably less screening effort. A systematic comparison of two different codon degeneracies was made by examining the relative quality of the identically sized enzyme libraries in relation to the degree of oversampling required in the screening process. The specific example in our case study concerns the conventional NNK codon degeneracy (32 codons/20 aa) versus NDT (12 codons/12 aa). The model reaction is the hydrolytic kinetic resolution of a chiral trans -disubstituted epoxide, catalyzed by the epoxide hydrolase from Aspergillus niger. The NDT library proves to be of much higher quality, as measured by the dramatically higher frequency of positive variants and by the magnitude of catalyst improvement (enhanced rate and enantioselectivity). We provide a statistical analysis that constitutes a useful guide for the optimal design and generation of "smarter" focused libraries. This type of approach accelerates the process of laboratory evolution considerably and can be expected to be broadly applicable when engineering functional proteins in general. [source] Atomic Properties of Amino Acids: Computed Atom Types as a Guide for Future Force-Field DesignCHEMPHYSCHEM, Issue 8 2003Paul L. A. Popelier Dr. Abstract The quantum chemical topology (QCT) is able to propose atom types by direct computation rather than by chemical intuition. In previous work, molecular electron densities of 20 amino acids and smaller derived molecules were partitioned into a set of 760 topological atoms. Each atom was characterised by seven atomic properties and subjected to cluster analysis element by element, that is, C, H, O, N, and S. From the respective dendrograms, 21 carbon atom types were distinguished, 7 hydrogen, 2 nitrogen, 6 oxygen, and 6 sulfur atom types. Herein, we contrast the QCT atom types with those of the assisted model building with energy refinement (AMBER) force field. We conclude that in spite of fair agreement between QCT and AMBER atom types, the latter are sometimes underdifferentiated and sometimes overdifferentiated. In summary, we suggest that QCT is a useful guide in designing new force fields or improving existing ones. The computational origin of QCT atom types makes their determination unbiased compared to atom type determination by chemical intuition and a priori assumptions. We provide a list of specific recommendations. [source] | ||||||||||||||||