Effectgerichte aanpak verwijdering P uit bodem- en slootwater duinzandgrond

Op bloembollenpercelen bij Egmond a/d Hoef worden twee zuiveringsmethoden getest om fosfaat te verwijderen uit bodem en slootwater. Het doel is het water te zuiveren van fosfaat om daarmee te voldoen aan de Europese Regelgeving voor de kwaliteit van oppervlaktewater

Environmental aspects of tensile membrane enclosed spaces

Buildings enclosed by fabric membranes are very sensitive to changes in environmental conditions as a result of their low mass and low thermal insulation values. Development in material technology and the understanding of the structural behaviour of tensile membrane structures along with the vast progress in computer formfinding software, has made it possible for structural design of tensile membrane structures to be approached with almost total confidence. On the contrary, understanding of the environmental behaviour in the spaces enclosed by fabric membrane and their thermal performance is still in its infancy, which to some extent has hindered their wide acceptance by the building industry. The environmental behaviour of tensile membrane structures is outlined and the possible use of the fabric’s topology and geometry particularly to enhance ventilation rates and airflow velocities within the enclosed space is discussed. A need for further research in this area is identified in order to fully realise the potential benefits offered by these structures

Bruikbaarheid van non-destructieve detectietechnologieën voor routinematige inspecties

Routinematige inspecties binnen het fytosanitaire domein vinden doorgaans plaats door middel van steekproefsgewijze visuele inspecties van de producten. Hierbij wordt gelet op de symptomen en/of aanwezigheid van schadelijke organismen. De vraag is, of er geen sneller, goedkoop èn betrouwbaar alternatief is. De onderzochte technologieën zijn onderverdeeld in: detectie van beeld; detectie van geur; detectie van geluid. Een tweede fase heeft het doel gehad de potentie, haalbaarheid en beperkingen van een deze detectietechnieken voor routinematige inspecties in beeld te brengen, ondersteund door experimentele gegevens en hands-on ervaringen

Percutaneous vertebroplasty is not a risk factor for new osteoporotic compression fractures: results from VERTOS II

Background and purpose: Pv is increasingly used as treatment for osteoporotic vcfs. However, controversy exists as to whether pv increases the risk for new vcfs during follow-up. The purpose of our research was to assess the incidence of new vcfs in patients with acute vcfs randomized to pv and conservative therapy. Materials and methods: Vertos ii is a prospective multicenter randomized controlled trial comparing pv with conservative therapy in 202 patients. Incidence, distribution, and timing of new vcfs during follow-up were assessed from spine radiographs. In addition, further height loss during follow-up of treated vcfs was measured. Results: After a mean follow-up of 11.4 Months (Median, 12.0; Range, 1-24 months), 18 New vcfs occurred in 15 of 91 patients after pv and 30 new vcfs in 21 of 85 patients after conservative therapy. This difference was not significant (P = .44). There was no higher fracture risk for adjacent-versus-distant vertebrae. Mean time to new vcf was 16.2 Months after pv and 17.8 Months after conservative treatment (Logrank, p = .45). The baseline number of vcfs was the only risk factor for occurrence (Or, 1.43; 95% Ci, 1.05-1.95) And number (P = .01) Of new vcfs. After conservative therapy, further height loss of treated vertebrae occurred more frequently (35 Of 85 versus 11 of 91 patients, p < .001) And was more severe (P < .001) Than after pv. Conclusions: Incidence of new vcfs was not different after pv compared with conservative therapy after a mean of 11.4 Months' follow-up. The only risk factor for new vcfs was the number of vcfs at baseline. Pv contributed to preservation of stature by decreasing both the incidence and severity of further height loss in treated vertebrae

Hepatic lipase gene expression is transiently induced by gonadotropic hormones in rat ovaries

Hepatic lipase (HL) gene expression was studied in rat ovaries. A transcript lacking exons 1 and 2 could be detected by reverse transcription-polymerase chain reaction (RT-PCR) in the ovaries of mature cyclic females and of immature rats treated with pregnant mare serum followed by human chorionic gonadotropin (hCG) to induce superovulation. By competitive RT-PCR the HL transcript was quantified. Low levels of HL mRNA were detected in ovaries of mature cyclic females and of immature rats. During superovulation HL mRNA was several fold higher than in mature cyclic rats and transiently increased to a maximum at 2 days after hCG treatment. Pulse-labelling of ovarian cells and ovarian slices with [35S]methionine followed by immunoprecipitation with polyclonal anti-HL IgGs showed de novo synthesis of a 47 kDa HL-related protein. Expression of the protein was transiently induced by gonadotropins with a peak at 2 days after hCG treatment. Induction of liver-type lipase activity occurred only after HL mRNA and synthesis of the HL-related protein had returned to pre-stimulatory levels. We conclude that in rat ovaries the HL gene is expressed into a variant mRNA and a 47 kDa protein. The expression of the HL gene in ovaries is inducible and precedes the expression of the mature, enzymatically active liver-type lipase

Growth hormone treatment in children with short stature born small for gestational age: 5-year results of a randomized, double-blind, dose-response trial

The growth-promoting effect of continuous GH treatment was evaluated over 5 yr in 79 children with short stature (height SD score, less than -1.88) born small for gestational age (SGA; birth length SD score, less than -1.88). Patients were randomly and blindly assigned to 1 of 2 GH dosage groups (3 vs. 6 IU/m2 body surface-day). GH deficiency was not an exclusion criterium. After 5 yr of GH treatment almost every child had reached a height well within the normal range for healthy Dutch children and in the range of their target height SD score. Only in children who remained prepubertal during the study period was the 5-yr increase in height SD score (HSDS) for chronological age significantly higher in the study group receiving 6 compared to 3 IU GH/m2 x day. Remarkably, the 5-yr increment in HSDS for chronological age was not related to spontaneous GH secretion, maximum GH levels after provocation, or baseline insulin-like growth factor I levels. GH treatment was associated with an acceleration of bone maturation regardless of the GH dose given. The HSDS for bone age and predicted adult height increased significantly. GH treatment was well tolerated. In conclusion, our 5-yr data show that long term continuous GH treatment at a dose of 3 or 6 IU/m2 x day in short children born SGA results in a normalization of height during childhood followed by growth along the target height percentile

A Conduit System Distributes Chemokines and Small Blood-borne Molecules through the Splenic White Pulp

Access to the splenic white pulp is restricted to lymphocytes and dendritic cells. Here we show that movement of molecules from the blood into these confined areas is also limited. Large molecules, such as bovine serum albumin (68 kD), immunoglobulin G (150 kD), and 500 kD dextran are unable to enter the white pulp, whereas smaller blood-borne molecules can directly permeate this compartment. The distribution is restricted to a stromal network that we refer to as the splenic conduit system. The small lumen of the conduit contains collagen fibers and is surrounded in the T cell areas by reticular fibroblasts that express ER-TR7. It also contains the chemokine CCL21. Conversely, in B cell follicles the B cell–attracting chemokine CXCL13 was found to be associated with the conduit and absence of ER-TR7+ fibroblasts. These results show heterogeneity of reticular fibroblasts that enfold the conduit system and suggest that locally produced chemokines are transported through and presented on this reticular network. Therefore, the conduit plays a role in distribution of both blood-borne and locally produced molecules and provides a framework for directing lymphocyte migration and organization of the splenic white pulp

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