Volatile chemicals in glands of the carpenter ant, Camponotus arminius

Camponotus arminius is a large black carpenter ant that occurs in tropical and sub-tropical Africa and has extensive foraging trails both in trees and on the ground. Analysis of excised mandibular glands has confirmed The presence of pentane-2,4-dione, n-hexanal, 4-methyl-3-heptanone, and mellein. Pentane-2,4-dione has not been reported from insects. The postpharyngeal gland contains n-heneicosane, n-tricosene, n-tricosane, n-pentacosene, n-pentacosane, and a significant amount of 11-methyl- n-tricosaneand 11-methyl- n-pentacosane. Dufours glands contain mainly n-undecane, n-tridecane, and two terpenoid compounds that are unknown in the genus Camponotus. These latter two compounds are geranyllinalool and probably geranylfarnesol

Spin dynamics in high-mobility two-dimensional electron systems

Understanding the spin dynamics in semiconductor heterostructures is highly important for future semiconductor spintronic devices. In high-mobility two-dimensional electron systems (2DES), the spin lifetime strongly depends on the initial degree of spin polarization due to the electron-electron interaction. The Hartree-Fock (HF) term of the Coulomb interaction acts like an effective out-of-plane magnetic field and thus reduces the spin-flip rate. By time-resolved Faraday rotation (TRFR) techniques, we demonstrate that the spin lifetime is increased by an order of magnitude as the initial spin polarization degree is raised from the low-polarization limit to several percent. We perform control experiments to decouple the excitation density in the sample from the spin polarization degree and investigate the interplay of the internal HF field and an external perpendicular magnetic field. The lifetime of spins oriented in the plane of a [001]-grown 2DES is strongly anisotropic if the Rashba and Dresselhaus spin-orbit fields are of the same order of magnitude. This anisotropy, which stems from the interference of the Rashba and the Dresselhaus spin-orbit fields, is highly density-dependent: as the electron density is increased, the kubic Dresselhaus term becomes dominant and reduces the anisotropy.Comment: 13 pages, 6 figure

Enhanced THz transmission apertures through sub-wavelength annular apertures

We report on the development of a surface micromachined process for the fabrication of coaxial apertures surrounded by periodic grooves. The process uses a combination of copper electroforming and the negative epoxy based resist, SU8, as a thin flexible substrate. The device dimensions are suitable for the implementation of filters at THz frequencies, and measurements show a pass band centred around 1.5 THz. These devices could form the basis of the next generation of THz biosensors

How to write an original article for the Journal of Orthopaedics and Traumatology

The abstract is the precise summary of the article, not a preface. As Baue wrote in a popular editorial of the Archives of Surgery in 1979, “writing a good abstract is not abstract writing” [6]. The main data have to be represented, as they allow readers to understand contents clearly. Sentences like “The paper reports...” or “The authors describe...” have to be avoided as well as any generic statements

Emergency medicine training in the Netherlands, essential changes needed

Since 2008, training for emergency physicians (EPs) in the Netherlands has been based on a national 3-year curriculum. However, it has become increasingly evident that it needs to expand beyond its initial foundations. The training period does not comply with European regulations of a minimum of 5 years. Adjusting to this European standard is a logical step. Experience with the 3-year Dutch training scheme has led to the general conclusion that this training period is too short. Recommendations for essential changes and the basis for their development are presented

Increasing incidence of ED-visits and admissions due to traumatic brain injury among elderly patients in the Netherlands, 2011–2020

Background and importance: Traumatic brain injury (TBI) is a leading cause of disability and mortality worldwide. Nowadays the highest combined incidence of TBI-related emergency department (ED) visits, hospitalizations and deaths occurs in older adults. Knowledge of the changing patterns of epidemiology is essential to identify targets to enhance prevention and management of TBI. Objective: To examine time trends of ED visits, admissions, and mortality for TBI comparing non-elderly and elderly people (aged ≥ 65 years) in the Netherlands from 2011 to 2020. Design: We conducted a retrospective observational, longitudinal study of TBI using data from the Dutch Injury Surveillance System (DISS) and Statistics Netherlands from 2011 to 2020. Outcome measure and analysis: The main outcome measures were TBI-related ED visits, hospitalizations, and mortality. Temporal trends in population-based incidence rates were evaluated using Poisson regression. We compared patients under 65 years and patients aged 65 years or older. Main results: From 2011 to 2020, absolute numbers of TBI related ED visits increased by 244%, and hospital admissions and mortality showed an almost twofold increase in patients aged 65 years and older. The incidence of TBI-related ED visits and hospital admission increased also in elderly adults, with 156% and 51% respectively, whereas the mortality remained stable. In contrast, overall rates of ED visits, admissions, and mortality, and causes for TBI did not change in patients younger than 65 years during the study period. Conclusion: This trend analysis shows a significant increase of ED-visits and hospital admission for TBI in elderly adults from 2011 to 2020, whereas the mortality remained stable. This increase cannot be explained by the aging of the Dutch population alone, but might be related to comorbidities, causes of injury, and referral policy. These findings strengthen the development of strategies to prevent TBI and improve the organization of acute care necessary to reduce the impact and burden of TBI in elderly adults and on healthcare and society.</p

Negative refraction and the spectral filtering of terahertz radiation by a photonic crystal prism

We demonstrate how micromachined photonic crystals can be used to negatively refract terahertz frequency light. The photonic crystals, which are constructed from conventional dielectric materials, manipulate the incident beam via interaction with their photonic bands. Consequently, we show that different components of a broadband beam incident on the structure may be positively or negatively refracted, depending upon its frequency and that the structure can be used as an effective spectral filter of THz radiation

Antifibrinolytics attenuate inflammatory gene expression after cardiac surgery

ObjectivesAnti-inflammatory effects of tranexamic acid and aprotinin, used to abate perioperative blood loss, are reported and might be of substantial clinical relevance. The study of messenger ribonucleic acid synthesis provides a valuable asset in evaluating the inflammatory pathways involved.MethodsWhole-blood messenger ribonucleic acid expression of 114 inflammatory genes was compared pre- and postoperatively in 35 patients randomized to receive either placebo, tranexamic acid, or aprotinin. These results were further confirmed by reverse transcription–polymerase chain reaction.ResultsOf the 23 genes exhibiting independently altered postoperative gene expression levels, 8 were restricted to the aprotinin group only (growth differentiation factor 3, interleukin 19, interleukin 1 family member 7, transforming growth factor α, tumor necrosis factor superfamily 10, tumor necrosis factor superfamily 12, tumor necrosis factor superfamily 13B, vascular endothelial growth factor α), whereas both aprotinin and tranexamic acid altered gene expression of 3 genes as compared with placebo (FMS-related tyrosine kinase 3 ligand, growth differentiation factor 5, interferon-α8). In general, less upregulation of pro-inflammatory, and more upregulation of anti-inflammatory, genes was observed for patients treated with antifibrinolytics. Gene expression affected by aprotinin coded mostly for proteins that function through serine proteases.ConclusionsThis study demonstrates that the use of tranexamic acid and aprotinin results in altered inflammatory pathways on the genomic expression level. We further demonstrate that the use of aprotinin leads to significant attenuation of the immune response, with several inhibitory effects restricted to the use of aprotinin only. The results aid in a better understanding of the targets of these drugs, and add to the discussion on which antifibrinolytic can best be used in the cardiac surgical patient

The 4^4He(e,e′p)(e,e'p) Cross Section at Large Missing Energy

The $(e,e'p)$ reaction on $^{4}{He}$ nuclei was studied in kinematics designed to emphasize effects of nuclear short-range correlations. The measured cross sections display a peak in the kinematical regions where two-nucleon processes are expected to dominate. Theoretical models incorporating short-range correlation effects agree reasonably with the data.Comment: 4 pages LaTeX, using espcrc1.sty and wrapfig.sty (included), two figures. Talk presented by J. Templon at the 15th Int. Conf. on Few-Body Problems in Physics, Groningen, The Netherlands, 22-26 July, 199

Cytomegalovirus immunity in allogeneic marrow grafting

Contains fulltext : 4452.pdf (publisher's version ) (Open Access