Synergies between Fibrillated Nanocellulose and Hot-Pressing of Papers Obtained from High-Yield Pulp.

To extend the application of cost-effective high-yield pulps in packaging, strength and barrier properties are improved by advanced-strength additives or by hot-pressing. The aim of this study is to assess the synergic effects between the two approaches by using nanocellulose as a bulk additive, and by hot-pressing technology. Due to the synergic effect, dry strength increases by 118% while individual improvements are 31% by nanocellulose and 92% by hot-pressing. This effect is higher for mechanical fibrillated cellulose. After hot-pressing, all papers retain more than 22% of their dry strength. Hot-pressing greatly increases the paper's ability to withstand compressive forces applied in short periods of time by 84%, with a further 30% increase due to the synergic effect of the fibrillated nanocellulose. Hot-pressing and the fibrillated cellulose greatly decrease air permeability (80% and 68%, respectively) for refining pretreated samples, due to the increased fiber flexibility, which increase up to 90% using the combined effect. The tear index increases with the addition of nanocellulose, but this effect is lost after hot-pressing. In general, fibrillation degree has a small effect which means that low- cost nanocellulose could be used in hot-pressed papers, providing products with a good strength and barrier capacity.

On-Site X-ray Fluorescence Spectrometry Measurement Strategy for Assessing the Sulfonation to Improve Chemimechanical Pulping Processes.

Minimizing the fiber property distribution would have the potential to improve the pulp properties and the process efficiency of chemimechanical pulp. To achieve this, it is essential to improve the level of knowledge of how evenly distributed the sulfonate concentration is between the individual chemimechanical pulp fibers. Due to the variation in quality between pulpwood and sawmill chips, as well as the on-chip screening method, it is difficult to develop an impregnation system that ensures the even distribution of sodium sulfite (Na2SO3) impregnation liquid. It is, therefore, crucial to measure the distribution of sulfonate groups within wood chips and fibers on a microscale. Typically, the degree of unevenness, i.e., the amount of fiber sulfonation and softening prior to defibration, is unknown on a microlevel due to excessively robust or complex processing methods. The degree of sulfonation at the fiber level can be determined by measuring the distribution of elemental sulfur and counterions of sulfonate groups, such as sodium or calcium. A miniaturized energy-dispersive X-ray fluorescence (ED-XRF) method has been developed to address this issue, enabling the analysis of sulfur distributions. It is effective enough to be applied to industrial laboratories for further development, i.e., improved image resolution and measurement time.

Lignin Inter-Diffusion Underlying Improved Mechanical Performance of Hot-Pressed Paper Webs.

Broader use of bio-based fibres in packaging becomes possible when the mechanical properties of fibre materials exceed those of conventional paperboard. Hot-pressing provides an efficient method to improve both the wet and dry strength of lignin-containing paper webs. Here we study varied pressing conditions for webs formed with thermomechanical pulp (TMP). The results are compared against similar data for a wide range of other fibre types. In addition to standard strength and structural measurements, we characterise the induced structural changes with X-ray microtomography and scanning electron microscopy. The wet strength generally increases monotonously up to a very high pressing temperature of 270 °C. The stronger bonding of wet fibres can be explained by the inter-diffusion of lignin macromolecules with an activation energy around 26 kJ mol-1 after lignin softening. The associated exponential acceleration of diffusion with temperature dominates over other factors such as process dynamics or final material density in setting wet strength. The optimum pressing temperature for dry strength is generally lower, around 200 °C, beyond which hemicellulose degradation begins. By varying the solids content prior to hot-pressing for the TMP sheets, the highest wet strength is achieved for the completely dry web, while no strong correlation was observed for the dry strength.

Symptom prevalence, frequency, severity, and distress during chemotherapy for patients with colorectal cancer.

PURPOSE: Early detection and improvements in treatment have increased survival after colorectal cancer (CRC), but studies investigating the multidimensional nature of treatment-related symptoms are rare. The aim of this study was therefore to describe the prevalence, frequency, and severity of symptoms and the distress they cause during the early treatment of patients with CRC undergoing chemotherapy. METHODS: Consecutive outpatients were asked to rate their symptoms during cycle 2 or 3 of chemotherapy, using the Memorial Symptom Assessment Scale. RESULTS: A total of 104 patients, 58 men and 46 women, evaluated their symptoms of the preceding week at one point during the treatment. The mean number of symptoms was 10.3 (SD, 7.7; range, 0-32). Highly prevalent symptoms were numbness/tingling in the hands/feet (64 %), lack of energy (62 %), feeling drowsy (49 %), and nausea (45 %). Symptoms with the highest scores for frequency, severity, and distress were lack of energy followed by difficulty in sleeping and numbness in the hands/feet. Lack of energy was noted as occurring almost constantly by 26 % and was rated as being severe or very severe by 12 % and as quite distressing or very distressing by 15 %. CONCLUSIONS: This study shows that patients with CRC receiving chemotherapy experience several distressing symptoms early in the treatment phase. In order to provide symptom control, oncology staff should consider evaluating the patient's symptoms early during treatment and plan adequate measures to minimize the impact of treatment-induced toxicity.

Teaching pelvic examination technique using professional patients: a controlled study evaluating students' skills.

OBJECTIVE: To compare the skills in pelvic examination technique between students who have had training with professional patients and a control group of students trained using clinical patients. DESIGN: Prospective controlled study. SETTING: University hospital. POPULATION: Students attending three consecutive courses in obstetrics and gynecology at Karolinska University Hospital. METHODS: A study group of 53 students received training in pelvic examination with professional patients and was compared with a control group of 34 students who were trained using clinical patients. MAIN OUTCOME MEASURES: The students' skills in pelvic examination technique were examined by teachers in a practical test. Students' skills were also evaluated by the students themselves and by the patients who participated in the examination. RESULTS: Students who had training with professional patients were more skilled in performing a pelvic examination and better prepared to examine their own patients than students trained using clinical patients. CONCLUSIONS: Training with professional patients is more effective in teaching pelvic examination technique than training with clinical patients. We recommend that the use of professional patients is considered in the training of medical students.

Medical students learning the pelvic examination: evaluation of a clinical patient model.

OBJECTIVE: To evaluate a clinical patient (CP) model for training in pelvic examination. DESIGN: Prospective clinical study. POPULATION: Students attending the course in obstetrics and gynecology and patients at Karolinska University Hospital, Stockholm, Sweden. MAIN OUTCOME MEASURES: Feelings, attitudes and skills of medical students and ratings from CPs in connection to training in the pelvic examination. METHODS: Each student participated in two training sessions at an outpatient clinic. The student participants answered questionnaires after each clinical session to measure different aspects of experiencing distress and to themselves rate the technical performance of the examination as well as the interaction with the CP. The CP answered questions about the examination, communication, information provided by the student and how they felt about participating in a teaching session. RESULTS: The students rated their own performance high including both interpersonal communication and the technical examination. It was felt that the teacher as well as the CP gave good support and guidance. The CPs rated interpersonal communication skills by the students high. The teaching session was regarded as important and useful by both students and CPs. CONCLUSIONS: We recommend the use of this type of training sessions where students are allowed to work more independently and train in the role as a doctor under supervision of the teacher.

Who wants to work in a rural health post? The role of intrinsic motivation, rural background and faith-based institutions in Ethiopia and Rwanda.

OBJECTIVE: To understand the factors influencing health workers' choice to work in rural areas as a basis for designing policies to redress geographic imbalances in health worker distribution. METHODS: A cohort survey of 412 nursing and medical students in Rwanda provided unique contingent valuation data. Using these data, we performed a regression analysis to examine the determinants of future health workers' willingness to work in rural areas as measured by rural reservation wages. These data were also combined with those from an identical survey in Ethiopia to enable a two-country analysis. FINDINGS: Health workers with higher intrinsic motivation - measured as the importance attached to helping the poor - as well as those who had grown up in a rural area and Adventists who had participated in a local bonding scheme were all significantly more willing to work in a rural area. The main result for intrinsic motivation in Rwanda was strikingly similar to the result obtained for Ethiopia and Rwanda combined. CONCLUSION: Intrinsic motivation and rural origin play an important role in health workers' decisions to work in a rural area, in addition to economic incentives, while faith-based institutions can also influence the decision.

Minimizing variability of cascade impaction measurements in inhalers and nebulizers.

The purpose of this article is to catalogue in a systematic way the available information about factors that may influence the outcome and variability of cascade impactor (CI) measurements of pharmaceutical aerosols for inhalation, such as those obtained from metered dose inhalers (MDIs), dry powder inhalers (DPIs) or products for nebulization; and to suggest ways to minimize the influence of such factors. To accomplish this task, the authors constructed a cause-and-effect Ishikawa diagram for a CI measurement and considered the influence of each root cause based on industry experience and thorough literature review. The results illustrate the intricate network of underlying causes of CI variability, with the potential for several multi-way statistical interactions. It was also found that significantly more quantitative information exists about impactor-related causes than about operator-derived influences, the contribution of drug assay methodology and product-related causes, suggesting a need for further research in those areas. The understanding and awareness of all these factors should aid in the development of optimized CI methods and appropriate quality control measures for aerodynamic particle size distribution (APSD) of pharmaceutical aerosols, in line with the current regulatory initiatives involving quality-by-design (QbD).

New data on African health professionals abroad.

BACKGROUND: The migration of doctors and nurses from Africa to developed countries has raised fears of an African medical brain drain. But empirical research on the causes and effects of the phenomenon has been hampered by a lack of systematic data on the extent of African health workers' international movements. METHODS: We use destination-country census data to estimate the number of African-born doctors and professional nurses working abroad in a developed country circa 2000, and compare this to the stocks of these workers in each country of origin. RESULTS: Approximately 65,000 African-born physicians and 70,000 African-born professional nurses were working overseas in a developed country in the year 2000. This represents about one fifth of African-born physicians in the world, and about one tenth of African-born professional nurses. The fraction of health professionals abroad varies enormously across African countries, from 1% to over 70% according to the occupation and country. CONCLUSION: These numbers are the first standardized, systematic, occupation-specific measure of skilled professionals working in developed countries and born in a large number of developing countries.

A new esomeprazole packet (sachet) formulation for suspension: in vitro characteristics and comparative pharmacokinetics versus intact capsules/tablets in healthy volunteers.

BACKGROUND: A packet (sachet) formulation of esomeprazole for suspension has been developed for use in patients who have difficulty swallowing. OBJECTIVES: This article reports the in vitro characteristics of the new esomeprazole formulation, including stability in suspension and suitability for administration orally or via enteral tubes. It also describes the pharmacokinetic profile of the esomeprazole 40-mg packet compared with that of existing solid dosage forms (capsules and tablets) in a clinical bioequivalence study. METHODS: The stability in suspension of the packet formulation was assessed after reconstitution at various strengths (2.5, 10, and 40 mg) and a different pH (3.4-5.0) in strength-appropriate volumes of water held at temperatures ranging from 5 degrees C to 37 degrees C for up to 60 minutes. Suitability for oral administration was examined in terms of reconstitution time and the actual dose delivered after simulated oral administration, as well as in terms of the actual dose delivered by enteral tubes ranging in diameter from 6 to 20 Fr. Chemical stability and suspension characteristics were also analyzed using alternative reconstitution vehicles (applesauce, apple juice, and orange juice). The comparative pharmacokinetics of the packet, capsule, and tablet formulations of esomeprazole were evaluated in a randomized, open-label, 3-way crossover study in healthy volunteers, who received single 40-mg doses of each formulation. Bioequivalence was assumed if the 90% CIs for the ratios of the geometric mean AUC and CmaX were between 0.80 and 1.25. Reversephase liquid chromatography with ultraviolet detection was used to assess the esomeprazole content and/or degradation products of esomeprazole in the tests for in-suspension stability, dose delivery, and acid resistance. Normal-phase liquid chromatography was used to assess the esomeprazole content of the plasma samples in the bioequivalence study. RESULTS: At the pH and temperature ranges investigated, the packet formulation was stable for up to 60 minutes after reconstitution. Chemical degradation was low (<0.1%) for all reconstitution vehicles investigated. Reconstitution time was 2 minutes with water and 9 to 10 minutes with apple or orange juice. Dose delivery was >/=98% after simulated oral administration and was generally >/=96% after administration via enteral tubes. Ninety-six healthy volunteers (56 women, 40 men; mean age, 24.9 years; mean weight, 68.9 kg) participated in the randomized, crossover, comparative pharmacokinetic study of the packet and capsule/tablet formulations. The estimated ratios of the geometric mean AUC and C(max) for the packet:capsule and packet: tablet formulations were 0.98 (90% CI, 0.93-1.03) and 0.99 (90% CI, 0.94-1.04), respectively. CONCLUSIONS: In these analyses, the packet (sachet) formulation of esomeprazole was chemically stable in suspension and when administered orally and via enteral tubes. The formulation had a short reconstitution time, remaining fully dispersed in water for at least 30 minutes, and was dispersed in applesauce, apple juice, or orange juice without compromising its stability or dispersion characteristics. The packet formulation met the regulatory definition for bioequivalence to the tablet and capsule formulations.

Teaching medical students gynaecological examination using professional patients-evaluation of students' skills and feelings.

Gynaecological examinations are especially sensitive, both for the inexperienced student and for the woman being examined. To assist the students in this process, we have introduced a separate training session for medical students using so-called professional patients during the first week of the course in obstetrics and gynaecology. The aim of the study was to evaluate the outcome, attitudes and feelings towards this type of training and to gain knowledge on how to further develop the method. After the training session, students, teachers and professional patients were asked to fill in anonymously different questionnaires assessing their views on the education. In conclusion students, teachers and professional patients found this training programme with professional patients to be of great value. It was felt that the teaching session reduced stress and anxiety; the students were relieved, calmer and more secure after the training. It is strongly recommended that this type of programme with professional patients should be used for teaching gynaecological examination techniques to medical students.

Mensuration and cleaning of the jets in Andersen cascade impactors.

PURPOSE: Fifty-three Andersen Cascade Impactors (404 stages) have been investigated using an automated visual stage mensuration technique. A cleaning method was suggested for stages with jets smaller than nominal diameters. The impact of nonapproved jet diameters on result parameters from particle size analysis was evaluated theoretically. METHODS: The jet diameters were measured using the Andersen Visual Inspection Device. A stepwise cleaning procedure was performed to recover the jets of noncompliant stages, and after each step a new stage mensuration was performed. RESULTS: The result of this extensive investigation, including measurements of each jet, is compared to other studies, to tolerance limits applied at AstraZeneca Lund and also to limits used by the manufacturer. Sixteen of the investigated stages were outside applied tolerance limits due to too small average diameters. Insertion of a go gauge into every jet of the stages was the only technique of those tested that increased the jet diameters toward nominal dimensions. Moreover, the relative standard deviation of the jet diameters decreased considerably after use of go gauges. CONCLUSIONS: Stage mensuration is a valuable technique for detection of improper jet dimensions of the Andersen Cascade Impactor, and use of go gauges is an effective cleaning method especially for jets with small diameters. However, use of stop/go gauges as a periodical quality control test on a small number of randomly selected jets was a poorly discriminating test, as both compliant and noncompliant stages would most probably pass such a test.

Adsorption of bilayers and multilayers of cationic and anionic co-polymers of acrylamide on silicon oxide.

Silica surfaces were consecutively treated with copolymers of cationic and anionic polyacrylamides (C-PAM and A-PAM, respectively) and the layer-by-layer build-up was continuously monitored with the aid of stagnation point adsorption reflectometry (SPAR). Four different charge densities of the cationic polymer and one charge density of the anionic polymer were studied. The solid substrate used in the investigation was an oxidized Si wafer, the charge of which was varied by performing the measurements at different pH. Adsorption measurements were performed both in deionized water and with a background electrolyte concentration of 0.01 M NaCl. The results show that the adsorption of C-PAM at pH 6 was dominated by electrostatic interactions. However, a significant nonionic contribution to the adsorption of C-PAM on SiO(2) was detected-when the results of adsorption measurements conducted in deionized water and in 0.01 M NaCl were compared. At pH 9, the adsorption of C-PAM onto SiO(2) was found to be geometrically restricted since the adsorption stoichiometry between the polymer charges and the charges on the surface was less than 1 irrespective of the charge of the C-PAM. Adsorption of the A-PAM onto the C-PAM covered surface increases as a function of the adsorbed charges in the first layer. Experiments showed that it was possible to form multilayers of polyelectrolytes on the SiO(2) surface provided the charge of the C-PAM was high enough. The critical charge of the polyelectrolyte for the formation of multilayers was also dependent on the charge of the substrate; that is, the lower the surface charge the higher the critical charge of the C-PAM. The substrate affected the amount of polyelectrolyte adsorbed up to the fifth layer. For further layers there was almost a stoichiometric relationship between the charges of the polyelectrolytes in consecutive layers. Results from studies of the formed multilayers with a quartz crystal microbalance (QCM-D) indicated that there was a close correlation between energy dissipation into the multilayers and a decrease in the adsorption as detected with SPAR. This in turn indicates that a decrease in the reflectometer signal does not necessarily indicate a decrease in adsorption.

Identification and characterization of a mammalian 14-kDa phosphohistidine phosphatase.

Protein histidine phosphorylation in eukaryotes has been sparsely studied compared to protein serine/threonine and tyrosine phosphorylation. In an attempt to rectify this by probing porcine liver cytosol with the phosphohistidine-containing peptide succinyl-Ala-His(P)-Pro-Phe-p-nitroanilide (phosphopeptide I), we observed a phosphatase activity that was insensitive towards okadaic acid and EDTA. This suggested the existence of a phosphohistidine phosphatase different from protein phosphatase 1, 2A and 2C. A 1000-fold purification to apparent homogeneity gave a 14-kDa phosphatase with a specific activity of 3 micro mol.min-1.mg-1 at pH 7.5 with 7 micro m phosphopeptide I as substrate. Partial amino-acid sequence determination of the purified porcine enzyme by MS revealed similarity with a human sequence representing a human chromosome 9 gene of hitherto unknown function. Molecular cloning from a human embryonic kidney cell cDNA-library followed by expression and purification, yielded a protein with a molecular mass of 13 700 Da, and an EDTA-insensitive phosphohistidine phosphatase activity of 9 micro mol.min-1.mg-1 towards phosphopeptide I. No detectable activity was obtained towards a set of phosphoserine-, phosphothreonine-, and phosphotyrosine peptides. Northern blot analysis indicated that the human phosphohistidine phosphatase mRNA was present preferentially in heart and skeletal muscle. These results provide a new tool for studying eukaryotic histidine phosphorylation/dephosphorylation.