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At least 235 records · Page 13Linked to original sources

Comparison of two digital hearing instrument fitting strategies.

Two different hearing instrument fitting strategies were compared in the laboratory and in a field test with regard to the benefit for hearing aid users and their satisfaction with the fitting. DSL [input/output (i/o)] fittings based on hearing threshold and uncomfortable levels for the subject were evaluated vs a prescriptive fitting method based on unaided loudness scaling. Twenty-one subjects were fitted diotically with both fitting strategies implemented in a digital hearing instrument (Siemens Prisma). The patients tested both fitting strategies sequentially in a 4 + 4-week field trial using a crossover study design. Speech recognition threshold measurements, sound quality ratings and paired comparisons of sound quality were performed for all conditions (unaided, DSL[i/o] fitting and loudness-based fitting). In addition, subjective benefit and preference were assessed with questionnaires. Speech audiometry did not reveal significant differences between the two fittings. DSL[i/o] fittings showed superior results in most sound quality tests and in the self-assessment of communication abilities while the loudness-based approach was slightly preferred in noisy environments. The results seemed to be influenced by the higher gain predicted by DSL[i/o]. This study provides no evidence that effort spent on loudness scaling leads to improved fitting results.

Audiometry, Speech↗

Influences of cardiorespiratory fitness levels and other predictors on cardiovascular disease mortality in men.

PURPOSE: This investigation quantifies the relation between cardiorespiratory fitness levels and cardiovascular disease (CVD) mortality within strata of other CVD predictors. METHODS: Participants included 25,341 male Cooper Clinic patients who underwent a maximal graded exercise test. CVD death rates were determined for low (least fit one-fifth), moderate (next two-fifths), and high (top two-fifths) cardiorespiratory fitness categories by strata of smoking habit, blood cholesterol level, resting blood pressure, and health status. There were 226 cardiovascular deaths during 211,996 man-years of follow-up. RESULTS: For individuals with none of the major CVD predictors (smoking, elevated resting systolic blood pressure, elevated blood cholesterol), there was a strong inverse relation (P = 0.001) between fitness level and CVD mortality. An inverse relation between CVD mortality and fitness level was seen within strata of cholesterol levels and health status. No evidence of a trend (P = 0.60) for decreased mortality was seen across fitness levels for individuals with elevated systolic blood pressure; however, a strong inverse gradient (P < 0.001) was seen across fitness levels for individuals with normal systolic blood pressure. There was a tendency for association between high levels of fitness and decreased CVD mortality in smokers compared with low and moderately fit smokers (P < 0.076). There was no significant association between level of fitness and CVD mortality for individuals with multiple (two or more) predictors (P = 0.325). Approximately 20% of the 226 CVD deaths in the population studied were attributed to low fitness level. CONCLUSIONS: Moderate and high levels of cardiorespiratory fitness seem to provide some protection from CVD mortality, even in the presence of well established CVD predictors.

Adult↗

Keratoconus fittings: apical clearance or apical support?

PURPOSE: To examine the relative merits of apical support and apical clearance fitting of rigid gas-permeable contact lenses for keratoconus. METHODS: After an historic review of fitting approaches for keratoconus, a case report is described in which an adventitious apical clearance fitting for early keratoconus might have been associated with accelerated progress of the ectasia. DISCUSSION: The hypothesis that apical clearance fittings increase the risk of accelerating ectasia progression in early keratoconus is examined in counterpoint to the hypothesis that apical support fittings increase the risk of apical scarring. Reference is made to the responses of normal corneas to apical clearance fitting and to apical contact fittings used in orthokeratology fittings. The tendency for corneas to mold to contact lens curvature is reviewed. The possibility that reduced corneal thickness or tissue softening and associated changes to the biomechanical properties of the cornea in keratoconus may facilitate molding with apical clearance fitting is examined. CONCLUSIONS: Known and putative risk factors for fitting complications that are associated with apical clearance and apical touch contact lens fitting are given as a basis for the reader to draw conclusions about the management of contact lens fitting for keratoconus. The possibility of symptomless adverse responses is a strong indication for frequent routine aftercare reviews.

Child↗

Aerobic fitness and the diurnal rhythm of blood pressure in adolescents.

We examined the effects of aerobic fitness and race on the diurnal rhythm of blood pressure of 175 healthy adolescents who performed a cycle ergometer maximal exercise test while oxygen consumption was measured. A median split of maximum oxygen consumption for boys and girls separately classified them as either "more-fit" or "less-fit" subjects. Ambulatory blood pressure recordings were also performed, and the data were analyzed for means while subjects were awake and asleep. Less-fit black boys had higher systolic pressures than more-fit black boys while awake (124 vs. 115 mm Hg; p less than 0.009) and asleep (117 vs. 108; p less than 0.001). Less-fit black boys also had higher systolic pressures than less-fit white boys while awake (114; p less than 0.002) and asleep (105; p less than 0.001), and they had higher systolic pressures than more-fit white boys while asleep (105; p less than 0.01). Less-fit black girls had higher systolic pressures than more-fit black girls while awake (116 vs. 109; p less than 0.004) and asleep (109 vs. 100; p less than 0.001). Less-fit black girls also had higher diastolic pressures than more-fit black girls while awake (71 vs. 66; p less than 0.002) and asleep (66 vs. 61; p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Interrater reliability of the Fitness Interview Test across 4 professional groups.

OBJECTIVE: This study investigated the interrater reliability of the Fitness Interview Test (FIT), revised edition, a semistructured interview that assesses fitness to stand trial. METHOD: Physicians, forensic psychologists, nurses, and graduate students in psychology were trained in the FIT, and they subsequently viewed 2 videotaped interviews of actual fitness assessments. Using the FIT, they rated the fitness of each defendant portrayed in the videotapes. RESULTS: For overall judgment of fitness, the average intraclass correlation based on the full samples of raters was found to be 0.98, and for most items on the FIT, intraclass correlations fell within the 0.80 s and 0.90 s. Reliability estimates were high across professional groups. CONCLUSIONS: Overall, this study provides further support for the psychometric properties of the FIT, as well as for the ability of various professionals to conduct reliable fitness assessments using the FIT.

Health Personnel↗

Respiratory fitness, free living physical activity, and cardiovascular disease risk in older individuals: a doubly labeled water study.

The objective of this study was to examine the importance of cardiorespiratory fitness vs. physical activity energy expenditure on selected cardiovascular disease risk factors in older individuals. One hundred and seventeen older individuals, 53 men (68 +/- 9 yr) and 63 women (67 +/- 7 yr), participated in the study. This cohort was divided into 4 groups: 1) high cardiorespiratory fitness and high physical activity, 2) high cardiorespiratory fitness and low physical activity, 3) low cardiorespiratory fitness and high physical activity, and 4) low cardiorespiratory fitness and low physical activity. Cardiorespiratory fitness (VO2max) was determined from a graded exercise test, physical activity energy expenditure was measured by doubly labeled water and indirect calorimetry, body composition was determined by dual energy x-ray absorptiometry, and dietary practices were determined by a 3-day recall. Cardiorespiratory fitness exerted greater effects on the cardiovascular disease risk profile than physical activity. That is, older individuals with higher levels of cardiorespiratory fitness, regardless of their physical activity levels, showed lower levels of fasting insulin (P < 0.01), triglycerides (P < 0.05), total cholesterol (P < 0.05), total to high density lipoprotein cholesterol ratio (P < 0.05), low density lipoprotein (P < 0.05), and lower waist circumference (P < 0.01). Moreover, individuals with a high cardiorespiratory fitness but low physical activity energy expenditure displayed a more favorable cardiovascular disease risk profile than individuals with low cardiorespiratory fitness and high physical activity energy expenditure. The results suggest that higher levels of cardiorespiratory fitness have greater cardioprotective effects than higher levels of free living physical activity in older individuals. Although these findings do not discount the health benefits of being physically active, it is possible that greater emphasis should be placed on aerobic exercise to increase cardiorespiratory fitness in the elderly.

Abdomen↗

Poorly fitting soft lenses affect ocular integrity.

PURPOSE: The purpose of this study was to determine whether borderline fitting soft lenses have a greater effect on ocular physiology than well fitting lenses. METHOD: The study was a retrospective analysis of data from seven soft lens clinical studies. The results of 63 eyes wearing borderline fitting lenses (31 tight and 32 loose fittings) were evaluated and compared with control eyes wearing optimally fitting lenses. Tight and loose lens fittings were defined as those showing tightness on push-up of > or =65% and < or =35%, respectively. An optimally fitting lens was defined as one showing tightness on push-up in the range 45-50% and decentration less than 0.7 mm. Slit lamp findings at the 1-month follow-up visit were compared. RESULTS: There was a significantly greater level of corneal staining among the tight lens wearing group than the controls (P=0.001); 68% of eyes wearing tight lenses showed staining as compared with 42% of eyes wearing well fitting lenses. There was also a greater level of conjunctival staining among tight lens wearing eyes but no significant difference in bulbar or limbal hyperemia. The loose lens wearing eyes showed a higher level of corneal staining: 69% vs 39% (P=0.04). In addition, the loose lens wearing eyes showed a higher level of bulbar (P=0.03) and limbal hyperemia (P=0.006). From supplementary analysis of 408 lens fittings, the incidence of corneal staining was found to increase with increasing tightness or looseness of fit. CONCLUSION: The results show that corneal staining and other physiological effects of soft lens wear vary with the quality of lens fit suggesting that practitioners should be less tolerant of sub-optimal fitting soft lenses.

Conjunctiva↗

Influences of cardiorespiratory fitness and other precursors on cardiovascular disease and all-cause mortality in men and women.

OBJECTIVE: To quantify the relation of cardiorespiratory fitness to cardiovascular disease (CVD) mortality and to all-cause mortality within strata of other personal characteristics that predispose to early mortality. DESIGN--Observational cohort study. We calculated CVD and all-cause death rates for low (least fit 20%), moderate (next 40%), and high (most fit 40%) fitness categories by strata of smoking habit, cholesterol level, blood pressure, and health status. SETTING: Preventive medicine clinic. STUDY PARTICIPANTS: Participants were 25341 men and 7080 women who completed preventive medical examinations, including a maximal exercise test. MAIN OUTCOME MEASURES: Cardiovascular disease and all-cause mortality. RESULTS: There were 601 deaths during 211996 man-years of follow-up, and 89 deaths during 52982 woman-years of follow-up. Independent predictors of mortality among men, with adjusted relative risks (RRs) and 95% confidence intervals (CIs), were low fitness (RR, 1.52;95% CI, 1.28-1.82), smoking (RR, 1.65; 95% CI, 1.39-1.97), abnormal electrocardiogram (RR, 1.64;95% CI, 1.34-2.01), chronic illness (RR, 1.63;95% CI, 1.37-1.95), increased cholesterol level (RR, 1.34; 95% CI, 1.13-1.59), and elevated systolic blood pressure (RR, 1.34; 95% CI, 1.13-1.59). The only statistically significant independent predictors of mortality in women were low fitness (RR, 2.10; 95% Cl, 1.36-3.21) and smoking (RR, 1.99; 95% Cl, 1.25-3.17). Inverse gradients were seen for mortality across fitness categories within strata of other mortality predictors for both sexes. Fit persons with any combination of smoking, elevated blood pressure, or elevated cholesterol level had lower adjusted death rates than low-fit persons with none of these characteristics. CONCLUSIONS: Low fitness is an important precursor of mortality. The protective effect of fitness held for smokers and nonsmokers, those with and without elevated cholesterol levels or elevated blood pressure, and unhealthy and healthy persons. Moderate fitness seems to protect against the influence of these other predictors on mortality. Physicians should encourage sedentary patients to become physically active and thereby reduce the risk of premature mortality.

Adult↗

US weight guidelines: is it also important to consider cardiorespiratory fitness?

BACKGROUND: The health consequences of weight ranges across low to moderate and high levels of cardiorespiratory fitness are unknown. OBJECTIVE: To evaluate the validity of the 1995 US weight guidelines, while considering cardiorespiratory fitness. METHODS: We followed 21,856 men, aged 30-83 y, who had a complete preventive medical examination, including a maximal treadmill exercise test and body composition assessment. There were 427 deaths (144 cardiovascular disease (CVD); 143 cancer; 140 others) during an average of 8.1 y of follow-up. We used Cox proportional hazards regression to examine the relations among cardiorespiratory fitness, body mass index (BMI, kg/m2), and all-cause and CVD mortality. RESULTS: After adjustment for age, examination year, cigarette smoking and alcohol intake, we observed that men with a BMI of 19.0 to < 25.0 and who were unfit had 2.3 times the risk of all-cause mortality (95% confidence interval (95% CI), 1.59-3.17, P < 0.001) compared with fit men in this BMI group (reference category). Unfit men with a BMI of 25.0 to < 27.8 also had a greater risk of all-cause mortality than fit men in the same BMI category. Fit but overweight men (BMI > or = 27.8) had a similar rate of all-cause mortality as physically fit men of normal weight (BMI 19.0 to < 25.0) and had a lower risk of all-cause mortality than unfit and normal weight men. Fit men of normal weight had the lowest CVD mortality, while unfit and overweight men experienced the highest CVD mortality. Unfit men had substantially higher CVD mortality than fit men in each BMI group. CONCLUSIONS: Unfit men had higher all-cause and CVD mortality than fit men. The health benefits of normal weights appear to be limited to men who have moderate or high levels of cardiorespiratory fitness. These data suggest that the 1995 US weight guidelines may be misleading unless cardiorespiratory fitness is taken into account.

Adult↗

Fit of the uncemented femoral component and the use of cement influence the strain transfer the femoral cortex.

To determine whether the strain patterns produced in the femoral cortex after uncemented femoral arthroplasty are influenced by the fit of the component and whether these patterns are different from those of cemented components, cortical surface strains of cadaveric femurs subjected to loads simulating single-limb stance were measured before and after the insertion of uncemented, collared, straight-stemmed femoral components. The effects of press fit, loose fit, and precise fit of the components were evaluated and were contrasted to the strain patterns occurring after insertion of cemented femoral components. Strains varied markedly, depending on the fit of the stem of the uncemented femoral component within the isthmus. Nearly normal patterns of femoral strain were produced when the femoral stem was fit precisely at the isthmus, and the proximal femoral strains were similar to those of the intact state. In contrast, press fit and loose fit at the isthmus altered the strain patterns. The proximal medial axial strains were significantly reduced with press fit, to a mean of 39% of normal (p < 0.05), and increased with loose fit, to a mean of 141% of normal (p < 0.05). The prostheses fixed with cement showed a mean reduction in proximal medial axial strains to 33% of normal, which was comparable with press fit uncemented components even though the collar was well seated. Thus, our findings indicated that, in the immediate postoperative period, femoral strain patterns can be influenced by the fit of an uncemented component within the isthmus and by the use of cement.

Aged↗

Metastable evolutionary dynamics: crossing fitness barriers or escaping via neutral paths?

We analytically study the dynamics of evolving populations that exhibit metastability on the level of phenotype or fitness. In constant selective environments, such metastable behavior is caused by two qualitatively different mechanisms. On the one hand, populations may become pinned at a local fitness optimum, being separated from higher-fitness genotypes by a fitness barrier of low-fitness genotypes. On the other hand, the population may only be metastable on the level of phenotype or fitness while, at the same time, diffusing over neutral networks of selectively neutral genotypes. Metastability occurs in this case because the population is separated from higher-fitness genotypes by an entropy barrier: the population must explore large portions of these neutral networks before it discovers a rare connection to fitter phenotypes. We derive analytical expressions for the barrier crossing times in both the fitness barrier and entropy barrier regime. In contrast with 'landscape' evolutionary models, we show that the waiting times to reach higher fitness depend strongly on the width of a fitness barrier and much less on its height. The analysis further shows that crossing entropy barriers is faster by orders of magnitude than fitness barrier crossing. Thus, when populations are trapped in a metastable phenotypic state, they are most likely to escape by crossing an entropy barrier, along a neutral path in genotype space. If no such escape route along a neutral path exists, a population is most likely to cross a fitness barrier where the barrier is narrowest, rather than where the barrier is shallowest.

Biological Evolution↗

Highly fit ancestors of a partly sexual haploid population.

Earlier, using the semi-deterministic solitary wave approach, we have investigated accumulation of pre-existing beneficial alleles in genomes consisting of a large number of simultaneously evolving sites in the presence of selection and infrequent recombination with small rate r per genome. Our previous results for the dynamics of the fitness distribution of genomes are now interpreted in terms of the life cycle of recombinant clones. We show that, at sufficiently small r, the clones dominating fitness classes, at the moment of their birth, are nearly the best fit in a population. New progeny clones are mostly generated by parental genomes whose fitness falls within a narrow interval in the middle of the high-fitness tail of fitness distribution. We also derive the fitness distribution for the distant ancestors of sites of a randomly sampled genome and show that its form is controlled by a single composite model parameter proportional to r. The ancestral fitness distribution differs dramatically from the fitness distribution of the entire ancient population: it is much broader and localized in the high-fitness tail of the ancient population. We generalize these results to the case of moderately small r to conclude that, regardless of fitness of an individual, all its distant ancestors are exceptionally well fit.

Family↗

Insulin sensitivity in physically fit and unfit children of parents with Type 2 diabetes.

AIMS: First-degree relatives of patients with Type 2 diabetes mellitus (T2DM) are often reported to be insulin resistant. We wanted to identify early metabolic abnormalities in this condition, and determine whether they are altered by regular physical training. METHODS: We measured insulin sensitivity using the euglycaemic glucose clamp technique and insulin response to oral glucose in 10 unfit (did not participate in routine physical exercise) offspring of T2DM parents and 10 unfit control subjects, and compared them with six fit (routinely swam for 3 h/day 5 days/week) offspring of T2DM parents and six fit controls with no family history of T2DM. RESULTS: Unfit offspring had a higher plasma glucose response than the other three groups. The mean area under the glucose curve was also significantly higher in unfit offspring than in the other three groups (12.6 +/- 0.6 vs. 10.4 +/- 0.4, 9.6 +/- 0.5, and 9.5 +/- 0.7 mmol/l per hour for the unfit controls, fit offspring and fit controls, respectively; P < 0.05). The corresponding insulin response of unfit offspring was significantly higher at 60 min in the oral glucose tolerance test (OGTT) that that of fit offspring or fit controls. In addition, the mean area under the insulin curve was significantly greater in unfit offspring than in either fit offspring or fit controls (868 +/- 172 vs. 294 +/- 71, 287 +/- 43 mmol/l per hour, respectively; P < 0.05). Moreover, the glucose disposal rate (GDR), measured using a euglycaemic clamp, was significantly lower in unfit and fit offspring than in unfit and fit controls (5.6 +/- 0.3 vs. 8.6 +/- 0.3 mg/kg per minute; P < 0.01 and 9.3 +/- 0.9 vs. 12.1 +/- 0.8 mg/kg per minute, respectively; P < 0.015), whereas the GDR was similar in unfit controls and fit offspring (8.6 +/- 0.4 vs. 9.3 +/- 0.9 mg/kg per minute; P > 0.05). CONCLUSION: These results support the concept that early metabolic abnormalities, as reflected by a decreased GDR (insulin sensitivity) in the offspring of T2DM patients, may be improved by increased physical fitness.

Administration, Oral↗

Errors associated with three methods of assessing respirator fit.

Three fit test methods (Bitrex, saccharin, and TSI PortaCount Plus with the N95-Companion) were evaluated for their ability to identify wearers of respirators that do not provide adequate protection during a simulated workplace test. Thirty models of NIOSH-certified N95 half-facepiece respirators (15 filtering-facepiece models and 15 elastomeric models) were tested by a panel of 25 subjects using each of the three fit testing methods. Fit testing results were compared to 5th percentiles of simulated workplace protection factors. Alpha errors (the chance of failing a fit test in error) for all 30 respirators were 71% for the Bitrex method, 68% for the saccharin method, and 40% for the Companion method. Beta errors (the chance of passing a fit test in error) for all 30 respirator models combined were 8% for the Bitrex method, 8% for the saccharin method, and 9% for the Companion method. The three fit test methods had different error rates when assessed with filtering facepieces and when assessed with elastomeric respirators. For example, beta errors for the three fit test methods assessed with the 15 filtering facepiece respirators were < or = 5% but ranged from 14% to 21% when assessed with the 15 elastomeric respirators. To predict what happens in a realistic fit testing program, the data were also used to estimate the alpha and beta errors for a simulated respiratory protection program in which a wearer is given up to three trials with one respirator model to pass a fit test before moving onto another model. A subject passing with any of the three methods was considered to have passed the fit test program. The alpha and beta errors for the fit testing in this simulated respiratory protection program were 29% and 19%, respectively. Thus, it is estimated, under the conditions of the simulation, that roughly one in three respirator wearers receiving the expected reduction in exposure (with a particular model) will fail to pass (with that particular model), and that roughly one in five wearers receiving less reduction in exposure than expected will pass the fit testing program in error.

Adult↗

Evolution of fitness in experimental populations of vesicular stomatitis virus.

The evolution of fitness in experimental clonal populations of vesicular stomatitis virus (VSV) has been compared under different genetic (fitness of initial clone) and demographic (population dynamics) regimes. In spite of the high genetic heterogeneity among replicates within experiments, there is a clear effect of population dynamics on the evolution of fitness. Those populations that went through strong periodic bottlenecks showed a decreased fitness in competition experiments with wild type. Conversely, mutant populations that were transferred under the dynamics of continuous population expansions increased their fitness when compared with the same wild type. The magnitude of the observed effect depended on the fitness of the original viral clone. Thus, high fitness clones showed a larger reduction in fitness than low fitness clones under dynamics with included periodic bottleneck. In contrast, the gain in fitness was larger the lower the initial fitness of the viral clone. The quantitative genetic analysis of the trait "fitness" in the resulting populations shows that genetic variation for the trait is positively correlated with the magnitude of the change in the same trait. The results are interpreted in terms of the operation of Muller's ratchet and genetic drift as opposed to the appearance of beneficial mutations.

Adaptation, Physiological↗

Genetic bottlenecks and population passages cause profound fitness differences in RNA viruses.

Repeated clone-to-clone (genetic bottleneck) passages of an RNA phage and vesicular stomatitis virus have been shown previously to result in loss of fitness due to Muller's ratchet. We now demonstrate that Muller's ratchet also operates when genetic bottleneck passages are carried out at 37 rather than 32 degrees C. Thus, these fitness losses do not depend on growth of temperature-sensitive (ts) mutants at lowered temperatures. We also demonstrate that during repeated genetic bottleneck passages, accumulation of deleterious mutations does occur in a stepwise (ratchet-like) manner as originally proposed by Muller. One selected clone which had undergone significant loss of fitness after only 20 genetic bottleneck passages was passaged again in clone-to-clone series. Additional large losses of fitness were observed in five of nine independent bottleneck series; the relative fitnesses of the other four series remained close to the starting fitness. In sharp contrast, when the same selected clone was transferred 20 more times as large populations (10(5) to 10(6) PFU transferred at each passage), significant increases in fitness were observed in all eight passage series. Finally, we selected several clones which had undergone extreme losses of fitness during 20 bottleneck passages. When these low-fitness clones were passaged many times as large virus populations, they always regained very high relative fitness. We conclude that transfer of large populations of RNA viruses regularly selects those genomes within the quasispecies population which have the highest relative fitness, whereas bottleneck transfers have a high probability of leading to loss of fitness by random isolation of genomes carrying debilitating mutations. Both phenomena arise from, and underscore, the extreme mutability and variability of RNA viruses.

Cell Line↗

Reliability, validity and utility of the Fitness Interview Test.

Psychiatrists are being asked more and more often by the courts to determine whether or not criminal defendants are fit to stand trial. However, the Criminal Code provides few statutory guidelines on what constitutes fitness to stand trial. Perhaps as a result of the lack of standards, psychiatrists have typically relied on traditional clinical assessment procedures in determining whether or not an individual is fit to stand trial. In an effort to improve the quality and consistency of forensic assessments, researchers have designed instruments to assess fitness to stand trial. In Canada, the Fitness Interview Test (FIT) was developed for this purpose. This study evaluated the FIT for its validity, reliability and utility in the assessment of fitness. The FIT was found to have excellent interrater reliability and scale homogeneity. In addition, it was able to discriminate between groups of defendants rates as being fit and or unfit to stand trial. The scale did not seem to be differentially sensitive to the diverse facets of fitness, which may be attributed to the format and content of the scale items. Caution is advised in the use of the FIT pending revision of the scale.

Adult↗

Analysis of telemetric time series data for periodic components using DQ-FIT.

DQ-FIT and CV-SORT have been developed to facilitate the automatic analysis of data sampled by radiotelemetry, but they can also be used with other data sampled in chronobiological settings. After import of data, DQ-FIT performs conventional linear, as well as rhythm analysis according to user-defined specifications. Linear analysis includes calculation of mean values, load values (percentage of values above a defined limit), highest and lowest readings, and areas under the (parameter-time) curve (AUC). All of these parameters are calculated for the total sampling interval and for user-defined day and night periods. Rhythm analysis is performed by fitting of partial Fourier series with up to six harmonics. The contribution of each harmonic to the overall variation of data is tested statistically; only those components are included in the best-fit function that contribute significantly. Parameters calculated in DQ-FIT's rhythm analysis include mesor, amplitudes, and acrophases of all rhythmic components; significance and percentage rhythm of the combined best fit; maximum and minimum of the fitted curve and times of their occurrence. In addition, DQ-FIT uses the first derivative of the fitted curve (i.e., its slope) to determine the time and extent of maximal increases and decreases within the total sampling interval or user-defined intervals of interest, such as the times of lights on or off. CV-SORT can be used to create tables or graphs from groups of data sets analyzed by DQ-FIT. Graphs are created in CV-SORT by calculation of group mean profiles from individual best-fit curves rather than their curve parameters. This approach allows the user to combine data sets that differ in the number and/or period length of harmonics included. In conclusion, DQ-FIT and CV-SORT can be helpful in the analysis of time-dependent data sampled by telemetry or other monitoring systems. The software can be obtained on request by every interested researcher.

Animals↗