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Leaf-cutting ants combine large-scale herbivory with fungus farming to sustain advanced societies. Their stratified colonies are major evolutionary achievements and serious agricultural pests, but the crucial adaptations that allowed this mutualism to become the prime herbivorous component of neotropical ecosystems has remained elusive. Here we show how coevolutionary adaptation of a specific enzy

Over the past few decades, significant social and economic transformations had a relevant correspondence in processes of territorial complexification, urban fragmentation and spatial injustice. Literature and research shows that these processes have also a very important temporal dimension, associated to a transition from an industrial society of synchronized rhythms to more heterogeneous everyday

At the beginning of the 21st Century, Zen Buddhism is no longer an unknown religion in the West. Zen-meditation enjoys great popularity, the books regarding the subject are among the bestsellers and the auditoriums are crowed if the topic concerns the bringing home of Zen Buddhism to a Western audience. At the same time Zen Buddhism today is by no means merely the religion of Zen Buddhists, but pr

Popular Abstract in Swedish Under de senaste årtiondena har både kraftsensorer och digitala kameror kommit att bli vanliga som sensorer i olika robotiktillämpningar. Denna avhandling behandlar olika problem inom visuell rörelseskattning och återkoppling, samt integrationen av dessa tekniker med reglering av kontaktkrafter för en industrirobot. Olika ämnen tas upp, från grundläggande teori till praOver the last decades, both force sensors and cameras have emerged as useful sensors for different applications in robotics. This thesis considers a number of dynamic visual tracking and control problems, as well as the integration of these techniques with contact force control. Different topics ranging from basic theory to system implementation and applications are treated. A new interface develo

The performance of poly(1-trimethylsilyl-1-propyne) (PTMSP)/silica nanocomposites was studied for membranes with a filler content between 0 and 50 wt%. An increase in permeability and a decrease in vapor selectivity was measured with increasing filler content. The free volume sizes and interstitial mesopore sizes of the composites were determined by use of positron annihilation lifetime spectrosco

ABSTRACT Radioimmunotherapy (RIT) consists of using monoclonal antibodies (mAbs) recognizing tumor-selective antigens, as carriers of cytotoxic radionuclides to tumor tissue. RIT has been effective in lymphoma but less successful in solid tumors. mAbs slowly diffuse from the vasculature into and through solid tumors, resulting in slow, limited accretion of antibodies. The outcome is a low tumor-to

We present spatial and dynamic information on the s = 1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)(2) center dot 2D(2)O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest-neighbor pair correlations, with short-range order at wave vectors Q(1) = 0.65(3) angstrom(-1) and Q(2) = 1.15(5) angstrom(-1) emerging belo

Objective: The pathogenesis and clinical significance of true umbilical cord knots remain controversial. Here, we tested the hypothesis of the presence of congenital oral mucosal changes in newborns with true umbilical cord knots. Study design: Seven consecutive infants with true umbilical cord knots and 50 gestational age- and sex-matched controls were enrolled. The proportion of oral frenulum ab

Objective: To evaluate the effects of eccentric isokinetic training on knee range of motion (ROM) of healthy subjects. Methods: The knee extensor and flexor isokinetic peak torques and ROM of flexion/extension and varus/valgus knee movements during gait of 18 healthy men (21.7 +/- 2.2 years; 1.73 +/- 0.10m; 68.7 +/- 9.4kg; body mass index: 22.6 +/- 2 kg/m(2)) were analyzed, before and after six we

Popular Abstract in Swedish Frisöryrket har en lång historia av stolta yrkesutövare, men frisörer arbetar i en komplex arbetsmiljö, där de utsätts för olika risker, inte bara luftvägsbesvär, utan även handeksem, muskelrelaterade besvär, stress, och ögonbesvär. I Sverige är 85 - 90 % av frisörerna kvinnor, varav de flesta är egenföretagare antingen som ensamägare till en salong eller tillsammans meLittle is known of respiratory symptoms in female hairdressers, and of the impact on the health-related quality of life (HRQoL), nor of knowledge of their own views on preventive work. The aim of this thesis was to examine the occurrence of asthma, symptoms and mechanism of bleaching-associated nasal symptoms, the effects on HRQoL and how young hairdressers reason about the work environment. A m

After 50 years the Alliance for Progress was launched, the policies for territorial planning in Latin America have proved to fail. The WB and the IADB, instruments of the US international politics for the consolidation of its global and regional hegemony, are its main financial and doctrinaire sources. These agencies’ logics prevail in the general and territorial planning. In the aftermath of the

Double-sided three-dimensional porous silicon chips, 6 mm x 6 mm, covered with a 40 nm gold (nano)layer, were fabricated from a porous silicon wafer. Scanning electron microscopy along with electrochemical characterisation showed sample conductivity, mechanical stability, and high surface area of the thus fabricated devices, viz. 10 times higher electrochemically active surface area compared to th

We report results from a large-scale nutrient fertilization experiment along a "megadiverse" (154 unique species were included in the study) 3,000-m elevation transect in the Peruvian Andes and adjacent lowland Amazonia. Our objectives were to test if nitrogen (N) and phosphorus (P) limitation shift along this elevation gradient, and to determine how an alleviation of nutrient limitation would man

The brick kiln at Saltsjö Boo is one of very few such structures known from medieval Sweden. Approx ¾ of the kiln has been excavated in successive short excavations from 2006 to 2011. Carbon 14 and TL (Thermoluminiscence) analyses indicate that the kiln has been in operation from c. 1250 to c.1450. This paper presents the results of the excavations and discusses the production of bricks and indust

1. Results are analysed from 11 experiments in which effects of fish addition and nutrient loading on shallow lakes were studied in mesocosms. The experiments, five in 1998, six in 1999, were carried out in six lakes, distributed from Finland to southern Spain, according to a standard protocol. 2. Effects of the treatments on 29 standard chemical, phytoplankton and zooplankton variables are examin

In the present paper an iterative time-reversal algorithm that retrofocuses an acoustic wave field to its controllable part is established. For a fixed temporal support, i.e., transducer excitation time, the algorithm generates an optimal retrofocusing in the least-squares sense. Thus the iterative time-reversal algorithm reduces the temporal support of the excitation from the requirement of negli