Non-parametric Comparison Tests Research Articles

Implementation of an Emergency Department Sign-Out Checklist Improves Transfer of Information at Shift Change

Transitions of care are ubiquitous in the emergency department (ED) and inevitably introduce the opportunity for errors. Few emergency medicine residency programs provide formal training or a standard process for patient handoffs. Checklists have been shown to be effective quality-improvement measures in inpatient settings and may be a feasible method to improve ED handoffs. To determine if the use of a sign-out checklist improves the accuracy and efficiency of resident sign-out in the ED. A prospective pre-/postinterventional study of residents rotating in the ED at a tertiary academic medical center. Trained research assistants observed resident sign-out during shift change over a 2-week period and completed a data collection tool to indicate whether or not key components of sign-out occurred and time to sign out each patient. An electronic sign-out checklist was implemented using a multi-faceted educational effort. A 2-week postintervention observation phase was conducted. Proportions, means, and nonparametric comparison tests were calculated using STATA. One hundred fifteen sign-outs were observed prior to checklist implementation and 114 were observed after. Significant improvements were seen in four sign-out components: reporting of history of present illness increased from 81% to 99%, ED course increased from 75% to 86%, likely diagnosis increased from 60% to 77%, and team awareness of plan increased from 21% to 41%. Use of the repeat-back technique decreased from 13% to 5% after checklist implementation and time to sign-out showed no significant change. Implementation of a checklist improved the transfer of information without increasing time to sign-out.

Pleomorphic adenoma of oral minor salivary glands: An investigation of its neoplastic potential based on apoptosis, mucosecretory activity and cellular proliferation

The aim of this study was to investigate the neoplastic potential of the PA of minor oral salivary glands measured by apoptosis (Bcl-2, Bax and p53), mucosecretory activity (MUC1), and cellular proliferation (Ki-67). Thirty-one cases of PA of the oral cavity and four controls (C) taken from normal oral minor salivary glands were analyzed using the immunohistochemistry technique. The proteins were detected utilizing a semi-quantitative method (scores) as follows: (-) negative ≤5%, (+) low 6-25%, (++) moderate 26-50% and (+++) high >50% of positive tumour cells. The apoptotic indices were evaluated by the ratio Bcl-2/Bax. Non-parametric comparison and correlation tests were used for analysis. The data showed high staining of anti-apoptotic protein Bcl-2 in both groups (PA=57.9%; C=67.7%) and a significantly lower expression of pro-apoptotic protein Bax (PA=22.7%; C=97.7%) and MUC1 (PA=14%; C=82.3%) in PA than in C (p<0.001). On the other hand, a similar expression of Ki-67 and p53 proteins (≤5%) was seen in both PA and C. In PA, only 2/31 cases showed the ratio Bcl-2/Bax<1.There was no difference in cellular expression with regard to clinical variables or clinical outcome (p>0.05). The neoplastic potential of PA could be associated with an imbalance in apoptotic processes and a lower index of cellular proliferation. Mucosecretory activity does not play a significant role in primary PA.

Technical note: Correlation between TQA data trends and TomoHD functional status

TomoTherapy Quality Assurance (TQA) is a software package developed to monitor certain aspects of machine performance. In this study, the TQA quantities or data trends most effective in monitoring energy drifts and magnetron stability were determined respectively. This retrospective study used data collected from three TomoHD units. The TQA modules investigated were Step‐Wedge Helical, Step‐Wedge Static, and Basic Dosimetry. First, the TQA quantities correlated with energy changes (|r|>0.85, where r is the Pearson's correlation coefficient) were found. The corresponding sensitivities to percentage depth dose (PDD) ratio changes were then calculated and compared. Second, the pulse‐by‐pulse dose stability was compared before and after each magnetron replacement using a nonparametric comparison test (Welch's t‐test), and the raw dose profiles were surveyed. In this study, exit detector flatness obtained in Basic Dosimetry was shown to be the most sensitive (r=0.945) to energy changes, followed by the energy differences in Step‐Wedge Static (r=0.942) and Step‐Wedge Helical (r=0.898). The three quantities could detect a PDD ratio change of 5.1×10−4,5.4×10−4, and 7.1×10−4, respectively. Pulse‐by‐Pulse Dose1 from Basic Dosimetry over a one‐week period before and after a magnetron replacement showed a significant difference (p<0.05) in only three of the nine instances. On the other hand, a raw output profile free from discontinuities, frequent dropped pulses and abnormal spikes was found to indicate that the magnetron would continue to function normally for a week 89% of the time.PACS numbers: 87.56.bd, 87.56.Fc, 84.40.Fe

Two types of exercise‐induced neuroplasticity in congenital hemiparesis: a transcranial magnetic stimulation, functional MRI, and magnetoencephalography study

Early unilateral brain lesions can lead to a persistence of ipsilateral corticospinal projections from the contralesional hemisphere, which can enable the contralesional hemisphere to exert motor control over the paretic hand. In contrast to the primary motor representation (M1), the primary somatosensory representation (S1) of the paretic hand always remains in the lesioned hemisphere. Here, we report on differences in exercise-induced neuroplasticity between individuals with such ipsilateral motor projections (ipsi) and individuals with early unilateral lesions but 'healthy' contralateral motor projections (contra). Sixteen children and young adults with congenital hemiparesis participated in the study (contralateral [Contra] group: n=7, four females, three males; age range 10-30y, median age 16y; ipsilateral [Ipsi] group: n=9, four females, five males; age range 11-31y, median age 12y; Manual Ability Classification System levels I to II in all individuals in both groups). The participants underwent a 12-day intervention of constraint-induced movement therapy (CIMT), consisting of individual training (2h/d) and group training (8h/d). Before and after CIMT, hand function was tested using the Wolf Motor Function Test (WMFT) and diverging neuroplastic effects were observed by transcranial magnetic stimulation (TMS), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG). Statistical analysis of TMS data was performed using the non-parametric Wilcoxon signed-rank test for pair-wise comparison; for fMRI standard statistical parametric and non-parametric mapping (SPM5, SnPM3) procedures (first level/second level) were carried out. Statistical analyses of MEG data involved analyses of variance (ANOVA) and t-tests. While MEG demonstrated a significant increase in S1 activation in both groups (p=0.012), TMS showed a decrease in M1 excitability in the Ipsi group (p=0.036), but an increase in M1 excitability in the Contra group (p=0.043). Similarly, fMRI showed a decrease in M1 activation in the Ipsi group, but an increase in activation in the M1-S1 region in the Contra group (for both groups p<0.001 [SnPM3] within the search volume). Different patterns of sensorimotor (re)organization in individuals with early unilateral lesions show, on a cortical level, different patterns of exercise-induced neuroplasticity. The findings help to improve the understanding of the general principles of sensorimotor learning and will help to develop more specific therapies for different pathologies in congenital hemiparesis.

GW24-e3036 Association between paraoxonase activity and coronary heart disease with normal serum lipid levels

ObjectivesTo investigate association between the reaction system of paraoxonase (PON), biomarkers of oxidative stress, and coronary heart disease (CHD) with normal serum lipid levels.MethodsA total of 60 randomised Han Chinese...

Permutation Test (PT) and Tolerated Difference Test (TDT): Two new, robust and powerful nonparametric tests for statistical comparison of dissolution profiles

The most popular way of comparing oral solid forms of drug formulations from different batches or manufacturers is through dissolution profile comparison. Usually, a similarity factor known as (f2) is employed; However, the level of confidence associated with this method is uncertain and its statistical power is low. In addition, f2 lacks the flexibility needed to perform in special scenarios. In this study two new statistical tests based on nonparametrical Permutation Test theory are described, the Permutation Test (PT), which is very restrictive to confer similarity, and the Tolerated Difference Test (TDT), which has flexible restrictedness to confer similarity, are described and compared to f2. The statistical power and robustness of the tests were analyzed by simulation using the Higuchi, Korsmayer, Peppas and Weibull dissolution models. Several batches of oral solid forms were simulated while varying the velocity of dissolution (from 30 min to 300 min to dissolve 85% of the total content) and the variability within each batch (CV 2-30%). For levels of variability below 10% the new tests exhibited better statistical power than f2 and equal or better robustness than f2. TDT can also be modified to distinguish different levels of similarity and can be employed to obtain customized comparisons for specific drugs. In conclusion, two new methods, more versatile and with a stronger statistical basis than f2, are described and proposed as viable alternatives to that method. Additionally, an optimized time sampling strategy and an experimental design-driven strategy for performing dissolution profile comparisons are described.

Regulation of the Potential Marker for Intestinal Cells, Bmi1, by β-Catenin and the Zinc Finger Protein KLF4

B lymphoma Mo-MLV insertion region 1 (Bmi1) is a Polycomb Group (PcG) protein important in gene silencing. It is a component of Polycomb Repressive Complex 1 (PRC1), which is required to maintain the transcriptionally repressive state of many genes. Bmi1 was initially identified as an oncogene that regulates cell proliferation and transformation, and is important in hematopoiesis and the development of nervous systems. Recently, it was reported that Bmi1 is a potential marker for intestinal stem cells. Because Wnt signaling plays a key role in intestinal stem cells, we analyzed the effects of Wnt signaling on Bmi1 expression. We found that Wnt signaling indeed regulates the expression of Bmi1 in colon cancer cells. In addition, the expression of Bmi1 in human colon cancers is significantly associated with nuclear β-catenin, a hallmark for the activated Wnt signaling. Krüppel-like factor 4 (KLF4) is a zinc finger protein highly expressed in the gut and skin. We recently found that KLF4 cross-talks with Wnt/β-catenin in regulating intestinal homeostasis. We demonstrated that KLF4 directly inhibits the expression of Bmi1 in colon cancer cells. We also found that Bmi1 regulates histone ubiquitination and is required for colon cancer proliferation in vitro and in vivo. Our findings further suggest that Bmi1 is an attractive target for cancer therapeutics.

Změna teplot sněhu při běhu na lyžích v obraze sekvenční termografie

Twenty years ago it was shown that friction increases the temperature of snow skis. Change of state permits for water skis glide. Th e aim of this pilot study was to determine whether dynamic infrared thermography is able to capture rapid changes in temperature of snow some areas (not just at one point), the ski tracks before and aft er passing. We monitored the snow on the track aft er 60 races two runners in various weights (86 and 73 kg) on two types of skis and lubrication (for classic and skating cross) and three diff erent speeds (3,04±0,180, 3,81±0,273 a 5,30±0,314 m.s-1). Measurements of infrared radiation and the calculation of snow surface temperature immediately before and aft er passing skier was carried out thermo-graphic system FLIR SC620 with 30 Mhz. Nonparametric Wilcoxon test for paired comparison of values was found signifi cant increases in temperature aft er the snow cleared the skies: runner A from -3,71 to -3,50 °C (p=0,000000) and runner B from -3,75 na -3,50 °C (p=0,000000). To return to the baseline temperature is within 5 seconds aft er passing. Diff erences were demonstrated in the heat of snow between runners with diff erent masses and for the use of diff erent types of skis. Th e study confi rmed the ability of dynamic infrared thermography to register a very rapid temperature changes of snow in an area immediately before and aft er crossing the cross-country skiers. Dimensional dynamic thermography would seem to contribute to the choice of the correct strategy and lubrication in ski racing. However, it is necessary to make a series of validation studies.

Body Mass Index (BMI) and mortality in patients with severe burns: Is there a “tilt point” at which obesity influences outcome?

Obesity is a serious health hazard. Despite advances in burn care severely obese patients with large burns have higher mortality compared with normal-weight patients. The Body Mass Index is the universal measure to define and classify obesity. This study aims to evaluate the effect of Body Mass Index (BMI) on mortality of severe burn patients. A retrospective study of 95 patients treated over 2-year period in a dedicated burn ITU. Mortality was studied in relation to BMI as well as demographic, burn characteristics well as length of hospital stay. Logistic regression model and non-parametric comparison tests were used for analysis. Mean age was 42 ± 22 years (mean ± SD), Total Burn Surface area (TBSA) 33 ± 16%, BMI 29 ± 7.5 (kg/m²) and hospital stay was 37 ± 33 days. Incidence of inhalation injury was 29% and over all mortality was 19%. By logistic regression age, TBSA and inhalation injury were separately associated with mortality. Patients with BMI ≥ 35 (kg/m²) had significantly higher mortality compared with patients with BMI < 25 (kg/m²) [p=0.037 (Fisher's exact test)]. Body Mass Index ≥ 35 (kg/m²) is a tilt point, which is associated with a higher than predicted mortality following burns when compared to burned patients with a normal BMI.

Inference of field‐scale fracture transmissivities in crystalline rock using flow log measurements

Characterization of transmissivity for crystalline rock is conducted through simulation by conditioning against borehole flow rates obtained from high‐resolution, in situ field measurements during extraction pumping. Full three‐dimensional discrete fracture network simulations are carried out according to specifications obtained from site characterization data in a stochastic Monte Carlo setting. A novel method of conditioning is thereby introduced and applied using nonparametric comparison tests, which provide quantifiable measures of accuracy enabling evaluation of simulated results against field measurements. The assumption of a constitutive relationship (perfect correlation) between fracture size and transmissivity is adopted. The method is evaluated against both single and multiple realizations, various domain size, and fracture length configurations and shown to be robust for the cases considered. When the introduced method of conditioning is applied, transmissivity parameterization can be inferred to a narrow range with a quantifiable accuracy in terms of a probability value. Results indicate that elementary interpretation of transmissivity based on homogenization of a porous medium will generally underestimate transmissivity. Further implications on advective transport for natural flow conditions are briefly evaluated, indicating advective breakthrough times can be overestimated up to a factor of about 10 in the median.

Association of invasion-promoting tenascin-C additional domains with breast cancers in young women

IntroductionTenascin-C (TNC) is a large extracellular matrix glycoprotein that shows prominent stromal expression in many solid tumours. The profile of isoforms expressed differs between cancers and normal breast, with the two additional domains AD1 and AD2 considered to be tumour associated. The aim of the present study was to investigate expression of AD1 and AD2 in normal, benign and malignant breast tissue to determine their relationship with tumour characteristics and to perform in vitro functional assays to investigate the role of AD1 in tumour cell invasion and growth.MethodsExpression of AD1 and AD2 was related to hypoxanthine phosphoribosyltransferase 1 as a housekeeping gene in breast tissue using quantitative RT-PCR, and the results were related to clinicopathological features of the tumours. Constructs overexpressing an AD1-containing isoform (TNC-14/AD1/16) were transiently transfected into breast carcinoma cell lines (MCF-7, T-47 D, ZR-75-1, MDA-MB-231 and GI-101) to assess the effect in vitro on invasion and growth. Statistical analysis was performed using a nonparametric Mann-Whitney test for comparison of clinicopathological features with levels of TNC expression and using Jonckheere-Terpstra trend analysis for association of expression with tumour grade.ResultsQuantitative RT-PCR detected AD1 and AD2 mRNA expression in 34.9% and 23.1% of 134 invasive breast carcinomas, respectively. AD1 mRNA was localised by in situ hybridisation to tumour epithelial cells, and more predominantly to myoepithelium around associated normal breast ducts. Although not tumour specific, AD1 and AD2 expression was significantly more frequent in carcinomas in younger women (age ≤40 years; P < 0.001) and AD1 expression was also associated with oestrogen receptor-negative and grade 3 tumours (P < 0.05). AD1 was found to be incorporated into a tumour-specific isoform, not detected in normal tissues. Overexpression of the TNC-14/AD1/16 isoform significantly enhanced tumour cell invasion (P < 0.01) and growth (P < 0.01) over base levels.ConclusionsTogether these data suggest a highly significant association between AD-containing TNC isoforms and breast cancers in younger women (age ≤40 years), which may have important functional significance in vivo.

Is nurse–patient agreement of importance to cancer nurses’ satisfaction with care?

This paper is a report of a study of situational (nurse-patient agreement), personal and occupational factors of potential importance to oncology nurses' satisfaction with care provided and general work satisfaction. Nurses have a general tendency to attribute to patients with cancer more problems and suffering than patients themselves report. However, little is known about whether dis/agreement between oncology nurses and patients with cancer concerning perceptions of patients' situation is of importance to nurses' satisfaction with their work. The study had a comparative and prospective design. Data were collected in 2005 using self-administrated questionnaires with 81 consecutively recruited nurse-patient pairs. Data were analysed with non-parametric tests (for comparison between subgroups) and with multiple regression analyses (for identifying predictors). Initial nurse-patient agreement concerning patients' emotional distress, coping resources and quality of life did not appear to be important to nurses' subsequent satisfaction with the care directed at a specific patient. However, higher satisfaction with care provided as well as general work satisfaction was reported by nurses with more experience of cancer care and with a lower workload. To improve oncology nurses' opportunities to provide high quality cancer care, novice nurses and advanced beginners in particular should receive support and nurses' working conditions must be improved. Further research is needed to examine whether there are other aspects of the nurse-patient relationship that contribute to oncology nurses' satisfaction with the care provided to specific patients.

Global Levels of Histone Modifications Predict Prognosis in Different Cancers

Cancer cells exhibit alterations in histone modification patterns at individual genes and globally at the level of single nuclei in individual cells. We demonstrated previously that lower global/cellular levels of histone H3 lysine 4 dimethylation (H3K4me2) and H3K18 acetylation (ac) predict a higher risk of prostate cancer recurrence. Here we show that the cellular levels of both H3K4me2 and H3K18ac also predict clinical outcome in both lung and kidney cancer patients, with lower levels predicting significantly poorer survival probabilities in both cancer groups. We also show that lower cellular levels of H3K9me2, a modification associated with both gene activity and repression, is also prognostic of poorer outcome for individuals with either prostate or kidney cancers. The predictive power of these histone modifications was independent of tissue-specific clinicopathological variables, the proliferation marker Ki-67, or a p53 tumor suppressor mutation. Chromatin immunoprecipitation experiments indicated that the lower cellular levels of histone modifications in more aggressive cancer cell lines correlated with lower levels of modifications at DNA repetitive elements but not with gene promoters across the genome. Our results suggest that lower global levels of histone modifications are predictive of a more aggressive cancer phenotype, revealing a surprising commonality in prognostic epigenetic patterns of adenocarcinomas of different tissue origins.

Nonparametric Partial Sequential Tests for Patterned Alternatives in Multisample Problems

In the present work we develop partial sequential nonparametric tests for multiple comparison. We provide tests for the identity of several unknown univariate continuous distribution functions against patterned alternatives. Our tests are based on Wilcoxon score. We conduct some Monte Carlo studies related to the proposed tests. We carry out a detailed comparison between the proposed procedures and the corresponding nonsequential procedures. We register significant gain in sample size through the proposed procedure, maintaining almost the same level and power for both the tests. We perform an analysis of life data arising out of a geological survey related to arsenic contamination. We also present some asymptotics in this context.

The Role of Neuropsychologic Tests in the Diagnosis of Attention Deficit Hyperactivity Disorder

Attention, memory, executive function, language, and visual-motor skills were evaluated in a sample of 621 children, 6 to 11 years old, to assess the discriminant validity of neuropsychologic testing. Attention deficit hyperactivity disorder cases (249) and controls (372) were identified and tested. Analysis of covariance, nonparametric comparison tests, effect sizes, discriminant function, factor analyses, and receiver-operator characteristics curve analyses were used to establish the best diagnostic cutoff points for each variable. Statistically significant differences were found on cognitive effort, auditory skills, continuous performance test, working memory, visual-motor skills, verbal comprehension, and executive function measures (P < 0.05); however, the effect of group sizes was low to modest (0.24 to 0.54). Receiver-operator characteristics curve analysis showed modest sensitivity and low specificity, demonstrating that an important proportion of the variance in test scores was overlapping. Factor analysis of neuropsychologic testing results revealed a structure of six factors each for attention deficit hyperactivity disorder, control, and combined samples. The latent variables produced one discriminant function with a total correct classification accuracy of 61.9%. Neuropsychologic tests should be used as Attention Deficit Hyperactivity Disorder diagnostic tools with caution, but they hold promise for identifying core cognitive deficits and processes that can aid prevention and intervention.

Metabolic syndrome components in Indian migrants with type 2 diabetes: A matched comparative study

To study the metabolic syndrome (MS) in Indian subjects with type 2 diabetes (T2D) in comparing them with controls from the Indian community and from the general population. An adapted definition of MS by the Third report of the National Cholesterol Education Program's Adult Treatment Panel III was used. We defined three groups matched for sex and age (+/-5 years). Non parametric tests for comparison of matched samples and conditional logistic regression were used. We selected 71 Indians with T2D (group 1) and two control groups with fasting blood glucose<6.1 mmol/L: 71 Indians (group 2) and 213 subjects from the general population (group 3). Patients were 24 to 76 years-old and each group contained 56% men. Globally, MS was identified in 77% of the group 1 when diabetes was taken into account. When diabetes was excluded there were 47% of MS in group 1, 18% in group 2 and 16% in group 3. The clusters of four factors (hypertension, large waist circumference, hypertriglyceridemia and Low HDL-C) were more common in Indians. The most frequent factors were hypertriglyceridemia and large waist circumference in Indians. Indians with T2D had a 5-fold higher risk of MS than the general population group, OR (95% CI): 4.93 (2.71 - 8.97); P<0.001. The high frequency of MS and of hypertriglyceridemia in Indians with T2D highlights the need for screening and management of MS in this population facing a high cardiovascular risk.

Plasma cell-free DNA as an indicator of severity of injury in burn patients

Raised levels of plasma cell-free DNA have been detected in various patient groups, including trauma patients. We hypothesized that plasma DNA is increased in burn patients and may represent an objective indicator of burn severity and have predictive as well as prognostic significance. This was a prospective clinical study with full ethical approval. With informed consent, blood samples were collected from 28 burn patients within 24 h of injury and from 12 control subjects. Plasma cell-free DNA was measured by real-time quantitative polymerase chain reaction (PCR) assay for the beta-globin gene. Descriptive analysis, non-parametric data comparison tests (Mann-Whitney) and correlation tests (Spearman rank) were performed on the data. Samples were taken at a mean time of 5.7 h after injury from 13 patients with flame/flash burns and 15 patients with scalds. Median plasma DNA levels in the control, scald and flame/flash burn patient groups were 287, 648 and 2685 kilogenome-equivalents/L, respectively. Plasma DNA levels correlated with the length of hospital stay, but not with admission to the intensive care unit (ICU) nor the length of ICU stay. DNA levels correlated with the burn surface area (Spearman rank r = 0.54, p = 0.04) and the number of operations needed (Spearman rank r = 0.55, p = 0.03) for scalds, but not for flame/flash burns. Plasma DNA is increased after burn injury and is significantly correlated with some outcome measures, including the length of hospital stay. DNA levels are higher in flame/flash patients than in scald patients; the difference may provide an objective indication of burn depth and inhalation injury.

The relationship between bullying, depression and suicidal thoughts/behaviour in Irish adolescents

This study examined the prevalence of depressive symptoms, including suicidal ideation/behaviour, among bullied and non-bullied young people. Participants were 209 students, 97 male and 112 female, attending eight urban post-primary schools and aged between 12 and 15 years. Participants were interviewed using the Schedule for Affective Disorders and Schizophrenia for School Aged Children - Present and Lifetime Version, the Hopelessness Scale for Children, the Scale for Suicide Ideation, and the Suicide Intent Scale. Data were analysed using a series of non-parametric comparison tests. Being a victim of bullying was found to be significantly associated with depression (χ2 = 10.986; df = 1; p = 0.001) and suicidal ideation (χ2 = 5.811; df = 1; p = 0.022). Results also indicated that victims were more likely to have reported a suicide attempt (χ2 = 5.995; df = 1; p = 0.022). Finally, those bullied were significantly more likely to have been referred to psychiatric services (χ2 = 6.661; df = 1;p = 0.011). These findings suggest that the issue of bullying needs to be re-addressed within Irish schools, with particular emphasis placed on further investigation into the psychological consequences thereof.

Efecto del tratamiento enzimático sustitutivo sobre el perfil lipídico en pacientes con enfermedad de Gaucher

Gaucher's disease (GD) is a lysosomal storage disorder, caused by a deficiency of the acid -glucocerebrosidase enzyme, which results in accumulation of lipids within macrophages. GD patients show decreased plasma total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) levels, as well as decreased apolipoprotein (apo) A-I and B. Conversely, concentrations of plasma apo E and the chitotriosidase (ChT) activity, a chitinase synthesized by activated macrophages, are increased. Enzyme replacement therapy (ERT) is effective and safe in reversing the clinical manifestations in symptomatic patients. The aim of this study was to evaluate the effect of ERT on the lipid profile of GD patients. 70 patients, from the Spanish Registry of Gaucher's disease (REEG), were divided into two groups: 54 under ERT, according to stablished criteria, and 16 without ERT. Plasma apolipoprotein, lipoprotein and lipid concentrations, and chitotriosidase activity were analyzed in both groups. Statistical analysis was carried out with the U-Mann Whitney non-parametric test for comparison of data. The group of GD patients under ERT showed significant increases of HDL-c (+38%) and apo A-I (+18%) levels, whereas no changes were observed in LDL-c and apo B levels. Conversely, chitotriosidase activity (-58%), plasma-apo E (-32%) and HDL-apo E (-26%) levels were dramatically reduced after ERT. No significant modifications were observed in the group without ERT. ERT in GD patients displays significant effects on the concentration of plasma lipoproteins, resulting in a less atherogenic lipid profile and in a reduction of activated macrophages.

Production Efficiency and Size in Norwegian Sawmilling

Production efficiency in the Norwegian sawmilling sector was investigated by means of data envelopment analysis, using individual mill observations from the period 1974-91. The resulting efficiency scores were evaluated with respect to size using censored regression analysis and non-parametric comparison tests. Average efficiency estimates indicated that the smallest mills ( h 5000 m 3 yr -1 ) were less efficient than large mills (lumber output > 25000 m 3 yr -1 ). During most of the period studied, average efficiency estimates for the smallest mills were significantly lower than for larger mills.