1,713 research outputs found
Weed problems in various tillage systems in the Nordic countries
There is an increasing use of various forms of reduced tillage or no-tillage in the Nordic countries. This will favour the growth of grass weed species and perennial species. Perennial creeping weeds like Elymus repens, Cirsium arvense, and Sonchus arvensis are important in all Nordic countries. Stationary weeds such as Taraxacum spp., Artemisia vulgaris and volunteer grassland species increase in areas with reduced tillage and especially no-tillage systems. Winter annual and biennial species such as Matricaria perforata, Poa annua, Alopecurus geniculatus and Stellaria media are frequently occuring weeds in reduced tillage systems in all countries, while Alopecurus myosuroides and Apera spica-venti are problems in Denmark and Southern parts of Sweden and Finland
Towards a better parametrisation of Skyrme-like effective forces: A critical study of the SkM force
Comment on "Theory of tailoring sonic devices: Diffraction dominates over refraction"
Recently N. Garcia et al. (Phys. Rev. E 67, 046606 (2003)) theoretically
studied several acoustic devices with dimensions on de order of several
wavelenghts. The authors discussed on experimental results previously reported
by several of us (F. Cervera et al., Phys. Rev. Lett. 88, 023902 (2002)). They
concluded that diffraction and not refraction is the ominating mechanism that
explain the focusing effects observed in those experiments. In this Comment we
reexamined their calculations and discussed why some of their interpretations
of our results are misleading.Comment: 2 pages, 2 figures, a comment on an articl
Managerial Practices that Support Lean and Socially Sustainable Working Conditions
Despite decades of using lean, there is little knowledge of how lean managerial practices affect working conditions. Thus, the aim of this study was to investigate in what ways managerial practices support socially sustainable working conditions (SSWCs) during a lean transformation. A mixed methods approach was used in this multiyear case study in a midsize Swedish manufacturing company. Assessment of work characteristics was combined with employee questionnaires and interviews with managers. Four practices were identified as instrumental for SSWCs: 1) a coherent lean approach with clear direction, 2) a value-creating leadership style comprising a participatorypromoting and caring leadership approach with joint focus on production and well-being, 3) conscious involvement of employees in a stepwise fashion, and 4) a focus on promoting meaningful jobs and health, aided by work environment management. Thus, managerial practices actively supporting important job resources as an integral part of the lean system seemed to support SSWCs
The Response of the Tracheal Epithelium to Concomitant Cis-Diamminedichloroplatinum (II) and Radiation. An Electron Microscopic Study in Rabbits
The ciliated epithelium of the rabbit trachea was irradiated with daily fractions of 2 Gy up to an accumulated dose of 20 Gy (total dose: 2, 6, 10, 16, or 20 Gy). Fifteen to forty-five minutes before the start of each irradiation 0.3 mg Cis-diamminedichloroplatinum (cis-DDP) was given by intraperitoneal injection to each rabbit. Examinations were carried out 1-10 days after each fractionation schedule, when specimens were taken for morphological investigations.
Scanning electron microscope (SEM) examination showed a gradual development of ciliary damage, from blebs on the cilia to swollen tips, broken and bent cilia and finally an epithelial injury with areas free from cilia, and a surface covered with microvilli-like structures. SEM also showed cell loss, and remnants of dead cells on the surface together with detritus. By transmission electron microscopy (TEM), ciliary damage, cell death and cell loss of the ciliated cell layer, as well as exfoliation of portions of goblet-like cells on the surface, could be confirmed. Scoring of SEM and TEM micro graphs showed that for the tracheal part treated with cis-DDP and radiation, the maximal damage was expressed in the dose group 10 Gy, and above this no further increase in the average reaction occurred. For the part of the trachea only exposed to cis-DDP, the damage increased with the dose. The difference observed speaks for an accelerated proliferation exerted by the radiation
Fully engineered homoepitaxial zinc oxide nanopillar array for near-surface light wave manipulation
We report accurate light wave manipulation by means of an inverse designed homoepitaxial ZnO
nanopillar array. Our proof-of-concept structure was optimized for focusing a near-surface light
beam which propagates in a free-space parallel to the metal top surface. The on-purpose positioned
and perpendicularly aligned vertical ZnO nanopillars were fabricated by homoepitaxial chemical
growth technique. The obtained focal distance of 28 (mű)m as well as the light intensity distribution
pattern was verified by three-dimensional finite-difference time-domain method. The demonstrated
approach can provide inter- and intrachip optical connections in the next generation ZnO
nanowire-based integrated photonic devices
Early Miocene carbonate ramp development in a warm ocean, North West Shelf, Australia
Although carbonate ramps are widely described from the geological record,there is still a debate on the relative influence of water temperature, trophicconditions and type of carbonate factories on their development. Theca2400 km long Australian North West Shelf is among the largest Cenozoic car-bonate provinces worldwide, and records a transition from an early Mioceneramp to a middle Miocene rimmed platform. This change is observable onpublicly available seismic data, giving the opportunity to investigate envi-ronmental influences on platform evolution. This study combines macro-scopic and petrographic descriptions of early Miocene strata cropping out inthe Cape Range Anticline (North West Cape, southern end of the North WestShelf) and of time-equivalent well cuttings from the adjacent, offshoreExmouth Sub-basin. Particular emphasis is placed on the identification oflarger benthic foraminifera at a broad generic level, because differing taxahave a limited range of habitable conditions that serve as environmentalproxies. The results show that early Miocene strata are dominantly com-posed of larger benthic foraminifera with minor coralline algae in the proxi-mal platform, grading to micropackstones in the more distal platform. Aramp margin is inferred from the lithological data on the basis of the lack offramework builders and the presence of open oceanic indicators. Facies shal-low upward through individual outcrops, with a proximal to distal trendtowards the north-west. These trends along outcrops are consistent with theseismic interpretations. Identification of taxa with warm, oligotrophic wateraffinity suggests that the ramp was formed in an oligotrophic and warmocean, despite the absence of coral reefs. Changes of carbonate facies withdepth do not seem to be associated with changes in ramp morphology, andthe latter may have been controlled by physical oceanic parameters, such asoffshore currents and waves.Early Miocene carbonate ramp development in a warm ocean, North West Shelf, AustraliapublishedVersio
Allelic loss at chromosome 13q12-q13 is associated with poor prognosis in familial and sporadic breast cancer.
Loss of heterozygosity (LOH) was analysed in 84 primary tumours from sporadic, familial and hereditary breast cancer using five microsatellite markers spanning the chromosomal region 13q12-q13 which harbours the BRCA2 breast cancer susceptibility gene, and using one other marker located within the RBI tumour-suppressor gene at 13q14. LOH at the BRCA2 region was found in 34% and at RBI in 27% of the tumours. Selective LOH at BRCA2 occurred in 7% of the tumours, whereas selective LOH at RBI was observed in another 7%. Moreover, a few tumours demonstrated a restricted deletion pattern, suggesting the presence of additional tumour-suppressor genes both proximal and distal of BRCA2. LOH at BRCA2 was significantly correlated to high S-phase values, low oestrogen and progesterone receptor content and DNA non-diploidy. LOH at BRCA2 was also associated, albeit non-significantly, with large tumour size and the ductal and medullar histological types. No correlation was found with lymph node status, patient age or a family history of breast cancer. A highly significant and independent correlation existed between LOH at BRCA2 and early recurrence and death. LOH at RBI was not associated with the above mentioned factors or prognosis. The present study does not provide conclusive evidence that BRCA2 is the sole target for deletions at 13q12-q13 in breast tumours. However, the results suggest that inactivation of one or several tumour-suppressor genes in the 13q12-q13 region confer a strong tumour growth potential and poor prognosis in both familial and sporadic breast cancer
A First Comparison of the responses of a He4-based fast-neutron detector and a NE-213 liquid-scintillator reference detector
A first comparison has been made between the pulse-shape discrimination
characteristics of a novel He-based pressurized scintillation detector
and a NE-213 liquid-scintillator reference detector using an Am/Be mixed-field
neutron and gamma-ray source and a high-resolution scintillation-pulse
digitizer. In particular, the capabilities of the two fast neutron detectors to
discriminate between neutrons and gamma-rays were investigated. The NE-213
liquid-scintillator reference cell produced a wide range of scintillation-light
yields in response to the gamma-ray field of the source. In stark contrast, due
to the size and pressure of the He gas volume, the He-based
detector registered a maximum scintillation-light yield of 750~keV to
the same gamma-ray field. Pulse-shape discrimination for particles with
scintillation-light yields of more than 750~keV was excellent in the
case of the He-based detector. Above 750~keV its signal was
unambiguously neutron, enabling particle identification based entirely upon the
amount of scintillation light produced.Comment: 23 pages, 7 figures, Nuclear Instruments and Methods in Physics
Research Section A review addresse
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