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Vocational education aims at preparing students for their future as professionals; thus, students are often required to undergo a form of on-the-job learning. Assessment of professional performance during on-the-job learning is not based on single observations, but on prolonged participation at the workplace culminating in judgement by a workplace educator. However, little is known about "how" educators reach a judgement. This paper, therefore, aims at exploring how educators inform their judgements about students' professional performance. We consider the workplace to be a participatory learning environment, which entails that judgement about professional performance should be made in relation to the community students participated in and that the educator from that community has a central role. Our study takes an explorative approach based on interviews and uses template analysis to generate insight. Findings revealed that educators use multiple strategies to gather and process information about students to inform their judgement. Findings also showed that assessment starts at the first meeting, when the educator forms a first impression of the student and judges whether or not the student is suitable for the job. Educators at the workplace also showed that they are aware of the context in which they form their judgement.

The assessment of workplace learning by educators at the workplace is a complex and inherently social process, as the workplace is a participatory learning environment. We therefore propose seeing assessment as a process of judgment embedded in a community of practice and to this purpose use the philosophy of inferentialism to unravel the judgment process of workplace educators by seeing it as an interrelated system of judgments, actions and reasons. Focussing on the unfolding of a process, we applied a longitudinal holistic case study design. Results show that educators are engaged in a constant judgment process during which they use multiple and adaptive frames of reference when forming their judgment about students. They construct an overarching image of students that develops throughout the placement, and their judgments about students go hand in hand with their actions relating to fostering independent practice. [ABSTRACT FROM AUTHOR]

In vocational education, students learn in different school-based and workplace-based learning environments and engage with different types of knowledge in these environments. Students are expected to integrate these experiences and make meaning of them in relation to their own professional knowledge base. This study focuses both on "what" types of knowledge students learn in these environments and "how" they integrate these different types of knowledge. Individual and group interviews were conducted with students, teachers and workplace supervisors in a vocational programme in the Netherlands. Results show that students recognise the importance of vocational knowledge learned in school-based learning environments while they are in the workplace and vice versa, and continuously contextualise knowledge to make it applicable for new circumstances. Also, students learn differently at school due to their experiences in the workplace.

A seventeen-month-old draft horse gelding was presented with acute abdominal bleeding following castration. After two blood transfusions and medical treatment, clinical parameters stabilized, and the horse seemed to recover. Four days after admission, the horse suddenly developed tachycardia, tachypnea and pyrexia. Electrocardiography revealed paroxysmal monomorphic ventricular tachycardia related to myocardial injury. The horse recovered progressively after medical treatment and returned to normal sinus rhythm. In this case report, the importance to monitor for myocardial injury and cardiac arrhythmias after acute hemorrhage is highlighted. [ABSTRACT FROM AUTHOR]

Students in competence-based senior secondary vocational education are expected to actively construct personal knowledge during school-based learning and workplace learning. This study introduces the construct "personal professional theory" (PPT) to monitor and analyse students' personal knowledge development. It aims to investigate the development of the content and nature of students' PPTs and their perceptions of learning processes in vocational education during school-based learning and workplace learning. One group of students (n=20) in the domain of Information and Communication Technologies (ICT) is followed during one course of 40 weeks in which they alternately participate in school-based learning and workplace learning. A longitudinal design (t=4) including semi-structured concept maps is used to reveal the content and nature of students' PPTs (n=240). Semi-structured interviews (n=10) and log files (n=39) are used to explore students' perceptions of their learning process. No significant differences are found between the four measurements concerning the content and nature of students' PPTs. However, the actual content of students' PPTs shows a relatively unsteady and changeable pattern. Additionally, students perceive workplace learning as an essential process for the development of their PPT. It is concluded that the development of students' PPTs involves knowledge compilation as well as thematic turbulence. (Contains 5 tables and 2 figures.)

Students in competence-based vocational education are expected to actively construct a personal professional theory, in which they integrate different types of knowledge and beliefs. Students' personal professional theories are seen as an important learning outcome of competence-based vocational education. However, it is unknown how personal professional theories can be measured. This study focused on measuring the content and nature of students' personal professional theories using a multi-method triangulation approach, in which 16 students in the domain of Social Work constructed a concept map, an interview and a self-report. The results show that the relatively structured methods (i.e., interviews and concept maps) reveal more insight into students' personal professional theories than less structured methods (i.e., self-reports). It is concluded that both structure as well as adequate prompts are important in the process of explicating personal professional theories. (Contains 6 tables, 2 figures and 1 footnote.)

In both the fields of educational practice and educational research the professional development of teachers was, is and is promising to remain an urgent and relevant topic. Practitioner research performed by teachers in professional learning communities and communities of practice is promising to serve their professional development. In addition, practitioner research and participation in these learning and working communities aim at explicating the locally existing tacit professional knowledge. Since practitioner research is also defined as a means to the aim of creating knowledge that is more relevant to the practice of education than the knowledge created by research institutes, we are concerned with the question of which mechanisms can be identified as enabling the production of public practice-based knowledge. Therefore we review three current books on practitioner research and professional communities.

Competence-based vocational education is based on a constructivist learning paradigm, where the development of students' personal professional knowledge is emphasised. However, there is a lack of insight into how students construct their own professional knowledge and what the content and nature of personal professional knowledge is. This article elaborates the concept Personal Professional Theory (PPT): a personal knowledge base in which professional knowledge and beliefs are internalised. PPTs are built upon a combination of declarative and procedural knowledge and are stored in the long-term memory. Furthermore, knowledge in PPTs refers to compiled knowledge which can be specified and applied to different professional situations. These PPTs develop through an interrelated process of internalisation and socialisation, in which students grow into the existing body of shared knowledge and collective norms, values and beliefs of professionals of an occupational domain. It is concluded that the elaboration of PPTs can be used to stimulate and monitor personal professional knowledge development in vocational education, but further research into the content and nature of PPTs is required.

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In vocational education, students learn in different school-based and workplace-based learning environments and engage with different types of knowledge in these environments. Students are expected to integrate these experiences and make meaning of them in relation to their own professional knowledge base. This study focuses both on what types of knowledge students learn in these environments and how they integrate these different types of knowledge. Individual and group interviews were conducted with students, teachers and workplace supervisors in a vocational programme in the Netherlands. Results show that students recognise the importance of vocational knowledge learned in school-based learning environments while they are in the workplace and vice versa, and continuously contextualise knowledge to make it applicable for new circumstances. Also, students learn differently at school due to their experiences in the workplace. [ABSTRACT FROM AUTHOR]

Botulinum toxin (BoNT) injections in the dystonic muscles is the preferred treatment for Cervical Dystonia (CD), but the proper identification of the dystonic muscles remains a challenge. Previous studies showed decreased 8-14 Hz autospectral power in the electromyography (EMG) of splenius muscles in CD patients. Cumulative distribution functions (CDF's) of dystonic muscles showed increased CDF10 values, representing increased autospectral powers between 3 and 10 Hz, relative to power between 3 and 32 Hz. In this study, we evaluated both methods and investigated the effects of botulinum toxin. Intramuscular EMG recordings were obtained from the splenius, semispinalis, and sternocleidomastoid muscles during standardized isometric tasks in 4 BoNT-naïve CD patients, 12 BoNT-treated patients, and 8 healthy controls. BoNT-treated patients were measured 4-7 weeks after their last BoNT injections and again after 11-15 weeks. We found significantly decreased 8-14 Hz autospectral power in splenius muscles, but not in the semispinalis and sternocleidomastoid muscles of CD patients when compared to healthy controls. CDF10 analysis was superior in demonstrating subtle autospectral changes, and showed increased CDF10 values in all studied muscles of CD patients. These results did not change significantly after BoNT injections. Further studies are needed to investigate the origin of these autospectral changes in dystonia patients, and to assess their potential in muscle selection for BoNT treatment. [ABSTRACT FROM AUTHOR]

Background The preferred treatment for cervical dystonia (CD) is injection of botulinum toxin in the dystonic muscles. Unfortunately, in the absence of reliable diagnostic methods it can be difficult to discriminate dystonic muscles from healthy muscles acting in compensation. We investigated if dystonic muscle activation patterns could be identified in cervical dystonia patients during a harmonized isometric contraction task. Furthermore, we investigated whether dystonia worsens at higher levels of voluntary contraction, which might further improve the identification of dystonic muscle activity. Methods An isometric device was used to investigate muscle activation during voluntary contraction tasks in 10 controls and 10 CD patients. Surface electromyography (EMG) of the sternocleidomastoidus, splenius capitis, and semispinalis capitis muscles was evaluated during a rest task and when performing submaximal (20%) and maximal voluntary contractions for eight head transversal force directions and for head twist. Two measures were developed to identify dystonic activation: 1) Muscle activity in the contraction direction in which the contribution of the muscle was lowest (Minimum EMG), and 2) the average muscle activity over all contraction directions (Total Mean EMG). Results Patients showed increased dystonic activity in the rest task and during submaximal contractions relative to controls, but not during maximal contractions. Increases in Minimum EMG indicated an inability of patients to deactivate dystonic muscles counteracting the task. Increases in Total Mean EMG indicated dystonic activity in all task directions. During maximal contractions these effects were absent in dystonic muscles. Dystonia is therefore found not to worsen at higher levels of isometric voluntary contraction. The activity of dystonic muscles modulated with different loading directions similar to controls. Using Minimum EMG 54% of the muscles clinically diagnosed as dystonic and 91% of non-dystonic muscles were predicted correctly. Conclusions Dystonic muscle activity was found in cervical dystonia patients during submaximal contractions in all task directions using a harmonized isometric task, but no differences were found during maximal contractions. With some adaptation this method may prove useful to identify dystonic muscles. [ABSTRACT FROM AUTHOR]

Objective Botulinum toxin injections in the dystonic muscles are the preferred treatment for cervical dystonia (CD), but proper selection of the dystonic muscles remains a challenge. We investigated the use of EMG coherence and autospectral analysis as discriminative tools to identify dystonic muscles in CD patients. Methods We compared the occurrence of 8–14 Hz autospectral peaks and 4–7 Hz intermuscular coherences between 10 CD patients and 10 healthy controls. Secondly, we compared the muscles with significant 4–7 Hz coherences with the muscles that were selected clinically for botulinum toxin treatment. Results Autospectral peaks between 8 and 14 Hz were significantly more often absent in the splenius capitis (SPL) muscles of CD patients compared to controls (p < 0.01). Contrary to previous findings, there was no significant difference in the occurrence of 4–7 Hz intermuscular coherences between patients and controls and the diagnostic accuracy of coherence analysis to identify the clinically dystonic muscles was low. Conclusion Intermuscular EMG coherence analysis cannot reliably discriminate patients from controls. Autospectral changes in the SPL muscles are a more discriminative feature of CD. In patients, coherence analysis does not seem to be a reliable method to identify dystonic muscles. The clinical relevance and the origin of the autospectral changes need further study. [ABSTRACT FROM AUTHOR]

Lake models account for the thermodynamic interaction between fresh water lakes and the atmosphere. During frost periods they predict ice thickness. A stand-alone version of the Fresh water Lake model (FLake) has been compared with the operational ice-growth model at the Royal Netherlands Meteorological Institute. Both models have been driven with various input data like observations and data from the Hirlam Aladin Research on Mesoscale Operational NWP In Europe (HARMONIE) model. The lake ice models are validated with indirect ice thickness measurements at Cabauw during the winter of 1996/1997 and with data from a voluntary observer network in the province of Friesland (The Netherlands) during the winter of 2012. FLake is shown to have predictive power and is competitive with the operational ice-growth model. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates HARMONIE, a non-hydrostatic numerical weather prediction (NWP) model, in the parameterisation testbed (KPT) of Koninklijk Nerdelands Meteorologisch Institut (KNMI). The study uses Cabauw, the advanced observation site in the Netherlands with focus on turbulence, shallow convection, and cloud formation. The study concludes that the KNMI parameterisation testbed and single column models are useful tools for model evaluation of fast local processes.

This study investigates the performance of privatized enterprises in a single sector, namely the plantation sector in Sri Lanka. The study provides an insight into the impact of privatization in the context of a developing economy and the impact of State and private ownership on enterprise performance. The panel data enabled the comparative study of enterprise performance under State ownership and management, State ownership and private management and, private ownership and management. It was revealed that after controlling for industry effects, privatization had led to significant increases in profitability, efficiency, capital investment, and output while employment levels had declined. Results were robust when checked for deliberate underperformance. Contrary to the proponents who espouse partial privatization as a solution to nationalist opposition to divesting of State assets, evidence indicates that induction of private management under State ownership had not been able to produce significant improvement in performance. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the applicability of fluorine-19 magnetic resonance spectroscopy ((19)F MRS) for monitoring in vivo the conversion of 5-fluorocytosine (5-FC) to 5-fluorouracil (5-FU) after using an attenuated Salmonella Typhimurium strain recombinant to provide cytosine deaminase (TAPET-CD). The (19)F MRS measurements were done on mice bearing the human colon tumour xenograft (HCT116). The intratumoural conversion is greater when TAPET-CD/5-FC is delivered intratumourally (i.tu.) than when TAPET-CD is delivered intravenously (i.v.) and 5-FC intraperitoneally (i.p.). Repeat measurements of the same tumour also yielded important information on the tumour colonization by TAPET-CD through the correlated 5-FC to 5-FU conversion efficacy. The in vivo MRS spectra were confirmed by in vitro (19)F MRS of perchloric acid extracts of the tumour tissue. No 5-FU metabolites were detectable in vivo in the tumours. However, the in vitro measurements revealed, besides 5-FC and 5-FU, the presence of small amounts of catabolites. Finally, spectra obtained in vitro from liver extracts of tumour-bearing mice treated i.tu. with TAPET-CD/5-FC showed no 5-FU and only little amounts of catabolites. Our data illustrate most importantly the potential of (19)F MRS to monitor biologically-based treatments involving cytosine deaminase. [ABSTRACT FROM AUTHOR]

Promising preclinical activity with agents blocking the function of vascular endothelial growth factor (VEGF) has been observed in various cancer types, especially with combination therapy. However, these drugs decrease microvessel density, and it is not known whether this reduced vessel density (VD) results in decreased delivery of concomitantly administered classical anticancer drugs. We designed an in vivo study to investigate the relation between VEGF-blocking therapy, tumoral blood vessels, and intratumoral uptake of anticancer drugs. Nude NMRI mice bearing colon adenocarcinoma (HT29) were treated with the anti-VEGFmAb A4.6.1 or placebo. After 1 week, CPT-11 was administered 1 h prior to killing the animals. In A4.6.1 treated tumours, there was a significant decrease in VD, more pronounced with potentially functional large vessels than endothelial cords. Interestingly, a trend to increased intratumoral CPT-11 concentration was observed (P=0.09). In parallel, we measured an increase in tumour perfusion, as estimated by high-performance liquid chromatography determination of intratumoural Hoechst 33342 concentration. In the growth delay study, CPT-11 was at least equally effective with or without pretreatment with A4.6.1. These data suggest that tumour vascular function and tumour uptake of anticancer drugs improve with VEGF-blocking therapy, and indicate the relevance for further investigations. [ABSTRACT FROM AUTHOR]

Isolated hepatic perfusion (IHP) with melphalan with or without tumour necrosis factor alpha (TNF-alpha) is currently performed in clinical trials in patients with hepatic metastases. Previous studies led to the hypothesis that the use of TNF-alpha in isolated limb perfusion causes specific destruction of tumour endothelial cells and thereby induces an increased permeability of tumour vasculature. However, whether TNF-alpha contributes to the therapeutic efficacy in IHP still remains unclear. In an in vivo rat liver metastases model we studied three different tumours: colon carcinoma CC531, ROS-1 osteosarcoma and BN-175 soft-tissue sarcoma which exhibit different degrees of vascularisation. IHP was performed with melphalan with or without the addition of TNF-alpha. IHP with melphalan alone resulted, in all tumour types, in a decreased growth rate. However in the BN-175 tumour addition of TNF-alpha resulted in a strong synergistic effect. In the majority of the BN-175 tumour-bearing rats, a complete response was achieved. In vitro cytoxicity studies showed no sensitivity (CC531 and BN-175) or only minor sensitivity (ROS-1) to TNF-alpha, ruling out a direct interaction of TNF-alpha with tumour cells. The response rate in BN-175 tumour-bearing rats when TNF-alpha was coadministrated with melphalan was strongly correlated with drug accumulation in tumour tissue, as only in these rats a five-fold increased melphalan concentration was observed. Secondly, immunohistochemical analysis of microvascular density (MVD) of the tumour showed a significantly higher MVD for BN-175 tumour compared to CC531 and ROS-1. These results indicate a direct relation between vascularity of the tumour and TNF-alpha mediated effects. Assessment of the tumour vasculature of liver metastases would be a way of establishing an indication for the utility of TNF-alpha in this setting. [ABSTRACT FROM AUTHOR]

Objective: The influences of flow, perfusion time, and concentration on melphalan (MN) lung levels in a rat model of isolated lung perfusion (ILuP) were studied. Methods: ILuP was performed in WAG/Rij rats by using a single-pass system with 0.5, 0.05, 0.01, and 0.005 mg of MN. Subsequently ILuP with 0.05 mg MN was performed during 30 min with a flow rate of 0.5 ml/min, during 60 min with a flow rate of 0.5 ml/min, and during 30 min with a flow rate of 1.0 ml/min. Results: The lung MN levels of 0.05 mg were significantly lower as compared with 0.5 mg (p = 0.02). In the second experiment, no significant differences were seen in lung levels of MN between the different groups. Conclusion: The final lung MN levels were only determined by the absolute amount administered. [ABSTRACT FROM AUTHOR]

Potential anticancer therapy with the fumagillin analog TNP-470 was investigated in the present project using subcutaneously growing rhabdomyosarcomas in rats. Specifically, influences of different tumor sizes at the start of treatment as well as dose/schedules were evaluated with this angiogenesis inhibitor. The results show a significant (p = < or = 0.01) reduction of the growth rate, even for relatively large-sized (> 7 cm3) tumors, when 50 mg/kg TNP-470 was used every other day for up to 3 or 5 injections. With 30 mg/kg TNP-470 injections, effects were seen only with tumors measuring < 7 cm3. The histologic examinations demonstrate an increase in necrosis, both in the center and in the peripheral part of TNP-470-treated tumors. Overall, both tumor volume and drug dose determine treatment outcome with the rat rhabdomyosarcoma. The results suggest that angiogenesis inhibitors could represent a valid component in the treatment of progressive tumor growth, also of large tumors as often encountered in clinics. The antivasculature therapy might also improve hypoxia/necrosis-related therapeutic approaches. [ABSTRACT FROM AUTHOR]

Several possible mechanisms for the synergistic anti-tumour effects between tumour necrosis factor alpha (TNF-α) and melphalan after isolated limb perfusion (ILP) have been presented. We found a significant sixfold increase in melphalan tumour tissue concentration after ILP when TNF-α was added to the perfusate, which provides a straightforward explanation for the observed synergism between melphalan and TNF-α in ILP. [ABSTRACT FROM AUTHOR]