Dataset for analyzing and modelling the eutrophication processes in groundwater-coastal lagoon systems: The La Pletera lagoons case study (NE Spain)

A comprehensive hydrogeological report was conducted to determine the origin, occurrence and processes affecting nitrogen in a Mediterranean coastal aquifer-lagoon system. Water levels, hydrochemical and isotopic data was gathered during a 4-year period in the La Pletera salt marsh area (NE Spain). They were collected from the alluvial aquifer, two natural lagoons and four other permanent lagoons excavated during a restoration process (in 2002 and 2016), two watercourses (the Ter River and the Ter Vell artificial channel), 21 wells (considering six of them for groundwater sampling) and the Mediterranean Sea. Potentiometric surveys were carried out seasonally, however twelve-monthly campaigns (from November 2014 to October 2015), and nine seasonal campaigns (from January 2016 to January 2018) were conducted for hydrochemical and environmental isotopes analyses. The evolution of the water table was analysed for each well, and potentiometric maps were plotted to determine the relationship between the aquifer and the lagoons, sea, watercourses, and groundwater flow. Hydrochemical data included physicochemical data measured in situ (temperature, pH, Eh, dissolved oxygen, and electrical conductivity), major and minor ions (HCO₃^-, CO₃^2-, Cl^-, SO₄^2-, F^-, Br^-, Ca²⁺, Mg²⁺, Na⁺, and K⁺), and nutrients (NO₂^-, NO₃^-, NH₄⁺, Total Nitrogen (TN), PO₄^3-, and Total Phosphorus (TP)). Environmental isotopes included stable water isotopes (δ¹⁸O and δD), nitrate (δ¹⁵N_NO3 and δ¹⁸O_NO3) and sulphate isotopes (δ³⁴S_SO4 and δ¹⁸O_SO4). Water isotopes were analysed for all campaigns, however, nitrate and sulphate isotopes water samples were only analysed in some particular surveys (November and December 2014; January, April, June, July and August 2015). Additionally, two more surveys for sulphate isotopes were conducted in April and October of 2016. The data generated through this research may be used as a starting point to analyse the evolution of these recently restored lagoons, and their future responses to global change. In addition, this dataset may be used to model the hydrological and hydrochemical behaviour of the aquifer.

Nitrogen in surface aquifer - Coastal lagoons systems: Analyzing the origin of eutrophication processes

Coastal lagoons can act as sinks and sources of a wide range of substances, including nutrients, and pollutants. In these ecosystems, primary production is limited more by nitrogen than by phosphorus. For this reason, they are significantly vulnerable to nitrate pollution. In this study, a joined analysis of surface and ground water was conducted to determine the origin, occurrence and processes affecting nitrogen fate in a Mediterranean coastal aquifer-lagoon system. This included the analysis of water levels, as well as hydrochemical and isotopes data evolution for a 4-year period, which revealed two important insights of nitrogen cycling within the system. Firstly, we detected different origins for nitrate pollution (a mixture of sewage, manure and chemical fertilizers), as well as their nearly complete attenuation in the alluvial aquifer due to heterotrophic and autotrophic processes, favoured by the presence of organic matter and Fe-minerals in its sediments. Secondly, due to its rapid assimilation, inorganic nitrogen peaks in the lagoons were mainly detected after storm events. While nitrate peaks may be attributed to surface water runoff, ammonium peaks may be related to organic nutrient cycling. In contrast, we did not detect continuous and low N inputs, associated to groundwater flow. These results depict the need of a more integrated management strategy of these aquifer-lagoon systems.

Quantifying (12/13)CH(4) migration and fate following sub-surface release to an agricultural soil

Following gas generation in a Geological Disposal Facility (GDF), (14)C-containing gases could migrate through the geosphere, eventually diffusing into soils at the Earth's surface. This paper reports summary results from laboratory and field experiments to obtain information on the probable rates of a) diffusive transport and b) oxidation of (12/13)CH(4) (as a surrogate for (14)CH4) in a typical agricultural soil in the UK. Rates of CH(4) oxidation were generally low in the field and undisturbed soil columns, though a re-packed column of homogenised topsoil oxidised ambient atmospheric CH(4) 20× faster than an undisturbed soil column. In contrast to low observed rates of CH(4) oxidation, the effective diffusion of CH(4) through the soil was rapid. Isotopically labelled CH(4) injected at a depth of 45 cm in the field diffused to the surface and exited the soil over a time period ranging from 8 to 24 h. The rate of CH(4) diffusion through the soil was increased by the presence of ryegrass roots which increased soil porosity and decreased water content. δ(13)C values for laboratory column soils after labelled CH(4) injection experiments showed no sign of residual (13)C, despite the extremely high δ(13)C values of the injected (12/13)CH(4). If laboratory observations are confirmed by measurements in field samples it can be concluded that the majority of (14)CH(4) from a GDF which enters a soil with low methanotrophic activity will be lost to the free atmosphere after diffusing rapidly through the soil column.

Determination of naphthenic acids in crude oils using nonaqueous ion exchange solid-phase extraction

A method is presented for the routine, rapid, and quantitative analysis of aliphatic and naphthenic acids in crude oils, based on their isolation using nonaqueous ion exchange solid-phase extraction cartridges. The isolated acid fractions are methylated and analyzed by gas chromatography and gas chromatography/mass spectrometry. The method is effective on both light and heavy oils and is capable of providing mechanistic information of geochemical significance on the origin of the acids in the oils. Analysis of oils that were solvent extracted from laboratory and field mesocosm marine sediment oil degradation studies indicate that this new method of analyzing the products of hydrocarbon biodegradation may be a useful tool for monitoring the progress of bioremediation of oil spills in the environment.

Massive left diaphragmatic separation and rupture due to coughing during an asthma exacerbation

We report a case of herniation of abdominal contents into the left hemithorax in a patient hospitalized with an acute exacerbation of asthma accompanied by paroxysms of coughing. There was no history of trauma. We believe this is the first reported case of diaphragmatic rupture complicating an asthma exacerbation. We review clinical features, pathophysiology, diagnosis, and treatment of diaphragmatic rupture in its most common setting, trauma, and discuss its occasional "spontaneous" occurrence.

Diagnosis and initial management of blunt pancreatic trauma: guidelines from a multiinstitutional review

OBJECTIVE

The authors' objective was to resolve the current controversies surrounding the diagnosis and management of blunt pancreatic trauma (BPT).

SUMMARY BACKGROUND DATA

The diagnosis of BPT is notoriously difficult: serum amylase has been claimed to be neither sensitive nor specific, and recent anecdotal reports have suggested a role for computed tomography. The therapy of BPT has been controversial, with some suggesting selective observation and others advocating immediate exploration to prevent a delay-induced escalation in morbidity and death.

METHODS

The authors conducted a retrospective chart review of documented BPT from six institutions, using a standardized binary data form composed of 187 items and 237 data fields.

RESULTS

A significant correlation between pancreas-specific morbidity and injury to the main pancreatic duct (MPD) was noted. Patients requiring delayed surgical intervention after an unsuccessful period of observation demonstrated notably higher pancreas-specific mortality and morbidity rates, principally because of the incidence of unrecognized injuries to the MPD. Although detection of MPD injuries by computed tomography was no better than flipping a coin, endoscopic pancreatography was accurate in each of the five cases in which it was used.

CONCLUSIONS

The principal cause of pancreas-specific morbidity after BPT is injury to the MPD. Parenchymal pancreatic injuries not involving the ductal system rarely result in pancreas-specific morbidity or death. Delay in recognizing MPD injury leads to increased mortality and morbidity rates. CT is unreliable in diagnosing MPD injury and should not be used to guide therapy. Initial selection of patients with isolated BPT for observation or surgery can be based on the determination of MPD integrity.

The conundrum of the Glasgow Coma Scale in intubated patients: a linear regression prediction of the Glasgow verbal score from the Glasgow eye and motor scores

BACKGROUND

The Glasgow Coma Scale (GCS), which is the foundation of the Trauma Score, Trauma and Injury Severity Score, and the Acute Physiology and Chronic Health Evaluation scoring systems, requires a verbal response. In some series, up to 50% of injured patients must be excluded from analysis because of lack of a verbal component for the GCS. The present study extends previous work evaluating derivation of the verbal score from the eye and motor components of the GCS.

METHODS

Data were obtained from a state trauma registry for 24,565 unintubated patients. The eye and motor scores were used in a previously published regression model to predict the verbal score: Derived Verbal Score = -0.3756 + Motor Score * (0.5713) + Eye Score * (0.4233). The correlation of the actual and derived verbal and GCS scales were assessed. In addition the ability of the actual and derived GCS to predict patient survival in a logistic regression model were analyzed using the PC SAS system for statistical analysis. The predictive power of the actual and the predicted GCS were compared using the area under the receiver operator characteristic curve and Hosmer-Lemeshow goodness-of-fit testing.

RESULTS

A total of 24,085 patients were available for analysis. The mean actual verbal score was 4.4 +/- 1.3 versus a predicted verbal score of 4.3 +/- 1.2 (r = 0.90, p = 0.0001). The actual GCS was 13.6 + 3.5 versus a predicted GCS of 13.7 +/- 3.4 (r = 0.97, p = 0.0001). The results of the comparison of the prediction of survival in patients based on the actual GCS and the derived GCS show that the mean actual GCS was 13.5 + 3.5 versus 13.7 + 3.4 in the regression predicted model. The area under the receiver operator characteristic curve for predicting survival of the two values was similar at 0.868 for the actual GCS compared with 0.850 for the predicted GCS.

CONCLUSIONS

The previously derived method of calculating the verbal score from the eye and motor scores is an excellent predictor of the actual verbal score. Furthermore, the derived GCS performed better than the actual GCS by several measures. The present study confirms previous work that a very accurate GCS can be derived in the absence of the verbal component.

Patterns of personality change across the life span

Six aspects of personality were examined for a sample of 211 individuals across either a 30- or 40-year time span. Latent curve analyses found an underlying pattern of lifetime change for self-confidence, cognitive commitment, outgoingness, and dependability. An underlying pattern of lifetime stability was found for assertiveness. No shared systematic underlying pattern could be fit to individuals' lifetime trajectories for warmth. Although individuals shared a single underlying pattern of change or stability for 5 of the 6 dimensions of personality considered here, they also showed differences in the degree and direction of personality change.

Patterns of personality change across the life span

Six aspects of personality were examined for a sample of 211 individuals across either a 30- or 40-year time span. Latent curve analyses found an underlying pattern of lifetime change for self-confidence, cognitive commitment, outgoingness, and dependability. An underlying pattern of lifetime stability was found for assertiveness. No shared systematic underlying pattern could be fit to individuals' lifetime trajectories for warmth. Although individuals shared a single underlying pattern of change or stability for 5 of the 6 dimensions of personality considered here, they also showed differences in the degree and direction of personality change.

Hotline in China: one way to help Chinese people

Due to lack of sufficient professional counselors and psychologists, telephone hotlines were established as a way to reach Chinese people.

Field triage of trauma patients based upon the ability to follow commands: a study in 29,573 injured patients

If a trauma system is to deliver "the right patient to the right hospital at the right time," a simple triage tool that can be used in the field to rapidly identify patients with a significant risk of morbidity and mortality is vital.

OBJECTIVE

The purpose of this study was to evaluate the effectiveness of the Glasgow Coma Scale's Motor Response Component (GMR) in identifying such patients.

METHODS

From patient records in a well established state trauma registry, the predictive power of the Glasgow Motor Score was compared with the predictive power of the Injury Severity Score (ISS), Trauma Score, and whole Glasgow Coma Scale Score (GCS), using discriminant analysis and logistic regression.

RESULTS

Complete data were available for analysis for 29,573 patients. Nine percent died. The analyses demonstrated that the GMR was almost as good as the TS and better than the other scores in identifying patients at risk of dying. The highest discriminant accuracy was obtained by predicting that patients with a GMR of 6 would live and that all others (GMR 1-5) were at risk of dying. This means separating patients according to whether or not they follow simple commands.

CONCLUSIONS

The study demonstrated the GMR to be a good predictor of mortality in injured patients. Patients at risk of dying can best be identified by separating patients into those who cannot follow simple commands (GMR 1-5) from all others. This rapid and simple assessment could be useful as a prehospital tool to identify patients at risk of dying. First responders and nonmedical personnel not skilled in the use of the Trauma Score can easily determine if victims are able to follow commands and potentially identify the patients who are likely to require urgent trauma center care.

Statistical Evidence in Salary Discrimination Studies: Nonparametric Inferential Conditions

Fairness in the allocation of salary is often evaluated using statistical reasoning. A common principle is that among employees of equal merit, there should be no systematic differences in salary distributions between demographic groups. In practice, complete information on merit may be lacking. When observed measures of merit are incomplete or unreliable, statistical analyses that use such measures may be misleading. We present theoretical, nonparametric conditions under which evidence from salary studies using observed merit measures can provide a basis for inferences of fairness. Two types of fairness are defined that contrast fairness with respect to true merit versus observed merit. Latent variable models that have been proposed for use in salary equity studies are reviewed as parametric special cases of the general conditions presented. These models are illustrated using real salary data, demonstrating their specification as structural models with latent means. Implications of the inferential conditions for empirical studies of salary equity are discussed.

A causal model of adolescent depression

We examined how family strengths, parent-adolescent communication, self-esteem, loneliness, age, and gender interrelate, and how this interaction influences depression in adolescents. The data were collected on a written questionnaire completed by 156 adolescents who were attending public schools in four communities in the midwestern United States. We developed a causal model to explicate the relationships among the variables hypothesized to affect adolescent depression and analyzed the data using path analysis via the LISREL VII program. Results showed a good fit of the model to the data. Loneliness and self-esteem had a direct effect on adolescent depression. Self-esteem had an indirect effect on depression through loneliness. Age directly and indirectly influenced depression through loneliness. Gender was significantly related to depression through self-esteem. Family strengths indirectly affected depression through self-esteem.

The cost of not wearing seat belts. A comparison of outcome in 3396 patients

Data from the North Carolina Trauma Registry were analyzed to determine the effect of seat belt usage on outcome in motor vehicle accidents. Of 6237 persons involved in motor vehicle accidents, data on seat belt usage were available for 3396. Of these, 1916 were not and 1480 were wearing seat belts. The mean hospital charge in belted patients was $10,500 +/- $18,200; and in unbelted patients, $15,250 +/- $26,300 (p < 0.001). The total hospital charges were $23 million for the 1508 patients not wearing seat belts. If the unbelted patients had outcomes similar to belted patients, the charges resulting from caring for the 1508 patients would have been $15.8 million, a potential savings of $7.2 million. There were 135 deaths among the unbelted patients (7.0%) and 47 deaths among the belted patients (3.2%) (p < 0.001). A similar projection of belted outcome for unbelted patients suggests that seat belt usage could have reduced the unbelted mortality rate by over one half. Patients wearing seat belts also had significantly shorter hospital stays, fewer days in the intensive care unit, and fewer days on the ventilator (p < 0.001). Seat belt usage is associated with a significant decrease in mortality rate, hospital charges, length of stay, intensive care unit stay, and ventilator requirements. Seat belts could have saved at least 74 lives and 7.2 million dollars during the period from October 1, 1987 to July 1, 1989 in patients seen in the seven trauma centers in North Carolina.

Head CT scanning versus urgent exploration in the hypotensive blunt trauma patient

In hypotensive blunt trauma patients with a diminished level of consciousness, it may be difficult to decide whether to proceed with immediate head CT scanning or urgent laparotomy or thoracotomy. The purpose of this study was to determine the frequency of emergency craniotomy and urgent laparotomy or thoracotomy in a group of 734 blunt trauma patients with initial hypotension (BP < 90 mm Hg systolic) admitted to the eight level I and II trauma centers in North Carolina. The mean initial systolic blood pressure was 64 +/- 26 mm Hg, and the mean Trauma Score was 8 +/- 5.8. Serious head injury (AIS head > or = 3) was present in 40% (293 of 734). Of 734 patients studied, 9.4% (69 of 734) died in the emergency department. Head CT scanning was performed on 47% (344 of 734) and produced positive results for 26% (202 of 734). Emergency craniotomy for intracranial hemorrhage was performed on 2.5% (18 of 734) (ten subdurals, three epidurals, and five other intracranial hemorrhages). Twenty-one percent (154 of 734) underwent urgent laparotomy, thoracotomy, or both. Overall hospital mortality for hypotensive blunt trauma patients was 36% (263 of 734). Although serious head injury occurs commonly (40%) in hypotensive blunt trauma patients, frequency of urgent laparotomy (21%) is 8.5 times greater than emergency craniotomy for intracranial hemorrhage (2.5%). This information may be used by trauma teams in prioritizing care for hypotensive blunt trauma patients.

Inferiorly based rectus abdominis flaps in critically ill and injured patients

Use of the rectus abdominis muscle as a free or pedicled flap is generally well tolerated by patients and accomplishes its intended purpose with minimal morbidity. In chronic or nonacute situations, high rates of success of tissue transfer and low donor site morbidity is expected. We have reviewed our results in 26 patients undergoing inferiorly based rectus abdominis muscle flaps with particular attention to the donor site. Patients with multiple injuries, who have had recent abdominal laparotomy, have a significantly higher morbidity rate. Dehiscence of the abdominal wound in 3 patients and a mortal donor site infection in 1 patient after transfer of a rectus flap has led to a careful examination of the cause for these complications. Careless closure of the midline laparotomy wound with subsequent elevation of a rectus flap lends itself to ischemia of the fascia and potential dehiscence. This is especially true in seriously ill patients on ventilators with abdominal distention and nutritional compromise. Alternate sources of tissue should be used if practical in these patients.

Component analysis in multivariate aging research

A method of components analysis, related to principal components analysis, is described for applications in multivariate cross-sectional or longitudinal data. The method may be useful to researchers seeking to reduce the number of observed variables through scale construction. The method creates component variables as weighted sums of the observed variables using weights that are identical across groups and occasions. The statistical and conceptual properties of these components are discussed. The method is contrasted with traditional principal components analysis and factor analysis. An application of the method is presented using longitudinal WAIS and WAIS-R data.

Vascular injuries in a rural state: a review of 978 patients from a state trauma registry

The demographics, etiology, and outcome of 1148 vascular injuries suffered by 978 patients reported from eight trauma centers in a largely rural state to a trauma registry (NCTR) data base containing 26,617 patients entered over a 39-month time interval were analyzed. Vascular injury patients were more frequently transferred by helicopter (18%), referred from other hospitals (45%), transfused more blood (8 units mean/24 hours), had higher mean ISS values (14 vs. 9), had lower systolic blood pressures on admission (113 vs. 128 mm Hg), had higher emergency department mortality (3.3%), and required immediate surgery more often (79%) when compared with nonvascular injury NCTR patients (p = 0.0001). Vascular injury patients had significantly longer hospital stays (13 vs. 10 days), longer ICU stays (5 vs. 4 days), and greater hospital costs ($22,500 vs. $12,300) while incurring more serious AIS values for the regions of the chest, abdomen, and extremities. One hundred twenty-nine (13.1%) died, 97 after admission compared with a 6.2% mortality for NCTR nonvascular injury victims. Forty-seven percent of vascular injuries were extremity lesions; the amputation rate was 1.3%; and management was most often by simple repair (41.9%) or patching (22.2%). Rural vascular injury patients had a high incidence of blunt trauma (43.4%) and were older (average, 51 years); they were transported by helicopter more often (30.3%) and were frequently referred from another hospital (77.8%); they had longer ICU, ventilator, and hospital stays and greater hospital charges; and they had higher mortality (14.2%) compared with urban vascular trauma victims. The data suggest a need for the trauma care system to focus on earlier recognition, stabilization, and rapid transportation of this most seriously injured group of patients.

Blood pressure and intellectual functioning in late midlife

To determine how much change in cognitive performance can be attributed to blood pressure status, 103 adults were assessed on two occasions approximately 11 years apart. Subjects' ages ranged from 49 to 63 years on the second occasion. Regression analyses were performed to determine how much variance in change in performance on the Digit Span, Block Design, Object Assembly, and Digit Symbol tests was accounted for by blood pressure status. Time 1 and Time 2 diastolic blood pressure, and change in hypertension medication significantly predicted Time 2 performance on the Digit Span Forward test even after Time 1 test performance, age, education, and gender were accounted for. The results further confirm the importance of assessing health functioning when studying age-related changes in cognitive performance.

Some Mathematical Relationships Between Three-Mode Component Analysis and Stationary Component Analysis

One application of three-mode component analysis is in the analysis of longitudinal multivariate data. Millsap and Meredith (1988) have developed a component analysis method for this application that uses stationary compositing weights. This article presents theorems giving constraints which must be satisfied for equivalency between the component representations provided by three-mode component analysis and by methods employing stationary compositing weights. In general, the two approaches will provide mathematically distinct representations.

The spectrum of abdominal injuries associated with the use of seat belts

Several recent reports have described abdominal injuries occurring as a result of seat belt use, raising concerns about seat belts as an agent of injury in motor vehicle crashes. The purpose of this study was to characterize the distribution of abdominal injuries after motor vehicle crashes in belted and unbelted patients admitted to trauma centers. The mortality was higher in unbelted than belted patients (7% vs. 3.2%, respectively, p less than 0.0001). Unbelted patients also had significantly more frequent and more severe head injuries (50.0% vs. 32.9%, respectively, p less than 0.001). The incidence of abdominal injury was equal in both unbelted patients (13.9%), but the spectrum of organs injured was different in the two groups. Gastrointestinal tract injuries (stomach, small bowel, colon and rectum) were significantly more frequent in belted vs. unbelted patients (3.4% vs. 1.8%, respectively, p = 0.001). The frequency of liver and spleen injuries was the same in both groups. This study demonstrates that in patients admitted to trauma centers after motor vehicle crashes, belted and unbelted patients have an equal incidence of abdominal injury, but belted and unbelted patients have a different spectrum of injuries. Hollow viscus injuries are more common in belted crash victims. Seat belt use was associated with significantly fewer head injuries and deaths. Physicians evaluating trauma victims after motor vehicle crashes should be aware of the fact that the types of abdominal injuries may vary substantially depending on seat belt use.

Comparison of the ability of adult and pediatric trauma scores to predict pediatric outcome following major trauma

The Pediatric Trauma Score (PTS) has been identified as the only accurate and adequate means of predicting outcome in pediatric trauma. In answer to the increasing number of trauma patients arriving at local hospitals, the ability of the adult Trauma Score (TS) to predict pediatric trauma outcome was tested. Of the total 2,604 pediatric trauma cases in the North Carolina State Trauma Registry, 441 had both a PTS and TS available for analysis. The primary measures of outcome were emergency department and hospital dispositions. Logistic regression demonstrated that TS (R2 = 0.50) was a stronger predictor of pediatric outcome and PTS (R2 = 0.35) for emergency department disposition and TS (R2 = 0.63) with PTS (R2 = 0.51) for hospital disposition. The correlation between TS and PTS was high (R = 0.8). Stepwise discriminant analysis demonstrated that TS was the stronger predictor of outcome and the PTS added only 9% (partial R2 = 0.09) more accuracy to TS for emergency department disposition and only 6% (partial R2 = 0.06) for hospital disposition. The results of this research demonstrate that TS is a useful method of predicting outcome in pediatric trauma. The use of both scores for each patient does not increase the predictive value of the scores.

Change and stability in adult intellectual functioning assessed by Wechsler item responses

Change in adult intellectual performance was assessed with longitudinal data from the Intergenerational Studies at the Institute of Human Development. Wechsler Intelligence data from two age cohorts spanning ages 18 to 61 were analyzed at the subtest and item level. Hotelling T2 analyses on sets of equivalent items from Wechsler subtests were studied to determine if change in response occurred between pairwise combinations of occasions of test administrations. We used Bowker's test to analyze data at the item level to determine the direction of change in performance. Consistent improvement in performance occurred between the ages of 18-40 and 18-54. Between the ages of 40 and 61, results showed mostly improved performance on the Information, Comprehension, and Vocabulary subtests, mixed change on the Picture Completion subtest, and decline on the Digit Symbol and Block Design subtests. The pattern of mixed change on the Picture Completion subtest indicated improvement on the easy items and decline on the difficult items. Decline in performance on the Block Design test occurred only for the most difficult items.

Effects of sensory and motor functioning on adult intellectual performance

This study examined longitudinal health and intelligence data to determine whether sensory or motor deficits account for some of the age-related intellectual changes that are commonly seen from midlife onward. Although sensory and motor functioning did not account for the age-related decrements in performance on speeded, visual perceptual tasks found for this sample in previous work, we did find that hearing deficits added error variance to performance estimates on two verbal subtests of the Wechsler scales.

Change and stability in adult intellectual functioning assessed by Wechsler item responses

Change in adult intellectual performance was assessed with longitudinal data from the Intergenerational Studies at the Institute of Human Development. Wechsler Intelligence data from two age cohorts spanning ages 18 to 61 were analyzed at the subtest and item level. Hotelling T2 analyses on sets of equivalent items from Wechsler subtests were studied to determine if change in response occurred between pairwise combinations of occasions of test administrations. We used Bowker's test to analyze data at the item level to determine the direction of change in performance. Consistent improvement in performance occurred between the ages of 18-40 and 18-54. Between the ages of 40 and 61, results showed mostly improved performance on the Information, Comprehension, and Vocabulary subtests, mixed change on the Picture Completion subtest, and decline on the Digit Symbol and Block Design subtests. The pattern of mixed change on the Picture Completion subtest indicated improvement on the easy items and decline on the difficult items. Decline in performance on the Block Design test occurred only for the most difficult items.

Continuous intravenous infusion of vinca alkaloid using a subcutaneously implanted pump in a canine model

A major drawback of infusions of the vinca alkaloids is the lengthy period of hospitalization which is often required for this novel technique of cancer therapy. A potentially useful system to deliver outpatient therapy has been investigated in a preclinical study. A self-contained infusion pump powered by a self-charging fluorocarbon system has been implanted SC in three dogs. The performance of two pumps which had been factory-calibrated to deliver 2.5 and 4.5 ml/day, respectively, was evaluated during 22 infusions of the vinca alkaloids (vincristine, 7; vinblastine, 7; and vindesine, 8). Infusions were given over a 5- to 7-day period and were repeated at 3-week intervals. No malfunctioning of the pumps occurred in over 500 cumulative days of use. The flow rates of the pumps were quite stable except in one animal whose increased flow rate was probably a consequence of fever due to self-induced inflammation about the pump pocket. No local or distant tissue reactions to the pump were observed. Decomposition of vincristine and vinblastine in the infusate at the end of 5- or 7-day infusions was minimal as determined by high-pressure liquid chromatography. The amount of decomposition of vindesine in the infusate was variable. Steady-state concentrations of vincristine during infusion were always greater than 10(-9) M, and were similar to those previously determined in our clinical infusion trials using a dosage of 0.5 mg/m2/day. Clinical evaluation of this system for prolonged infusions of vincristine and other vinca alkaloids appears to be warranted.

Effect of anesthesia and splenectomy on antibody response to pneumococcal polysaccharide immunization

Whether anesthesia-induced immunosuppression and postsplenectomy decreased antibody response are important in the timing of postsplenectomy pneumococcal vaccination was tested in 57 inbred 150 to 175 gm Fischer 344 rats immunized three weeks preoperatively (Group 1), immediately after anesthesia (Group II), and three weeks postoperatively (Group III). Groups IV and V were not immunized. All rats had splenectomy and one hour of 1 per cent halothane anesthesia. After intraperitoneal immunization of the rats with 5 mu g of Type III pneumococcal polysaccharide, weekly serum antibody levels were determined by radioimmunoassay. Six weeks postoperatively, Groups I through IV received an intravenous LD50 dose of Type III pneumococcus; Group V was challenged one week after operation. Survival was assessed every 12 hours for one week. Antibody responses among the groups were statistically equal, except on day 4 and day 26 postimmunization. On day 4, Group I had higher levels than Groups II and III (P less than .05), showing the spleen's role in early antibody production, and on day 26, Group I had much lower levels than Group II (P less than .05), indicating a short-term depressive effect of anesthesia and operation on ongoing antibody formation. Survival was equal among Groups I through IV. Survival in Group V was poorer than in Group IV (P less than 0.5), probably indicating that nonsplenic sites had acquired an enhanced ability to clear pneumococcus. The study shows, therefore, that anesthesia and splenectomy do not affect the timing of pneumococcal vaccination postsplenectomy.

Spouse similarity in newlyweds with respect to specific cognitive abilities, socioeconomic status, and education

Newlywed spouses (N = 215 couples) were tested on 21 tests of specific cognitive abilities and responded to a questionnaire on their educational and socioeconomic (SES) background. A comparison of the present spouse correlations with those of long-standing marriages suggests that spouses resemble each other in abilities from the start and that the degree of resemblance changes little over time. The low spouse correlations for SES of origin (their parents) suggests that education is the chief SES variable by which spouse selection takes place. Spouse resemblance in education and parental SES could explain almost all of the spouse correlations in perceptual speed and spatial ability. However, a small but significant degree of spouse similarity in verbal and reasoning abilities was independent of education and SES.

A longitudinal study of spatial ability

A number of studies have lent support to the sex-linked major gene theory of spatial ability. Expectations arising from this theory (although not necessarily unique to it) are that spatial ability can be measured in children, that it is the same as spatial ability in adults, and that an individual's position in a distribution of spatial ability remains unchanged over time. Results of a longitudinal experiment utilizing test scores of 76 high school students and their earliertest scores provide confirmatory evidence for these expectations.

A Stochastic Model For Repeated Testing

The paper suggests an extension of current probability models of mental testing to include practice effects resulting when the same subject responds t o the same ability test item on several occasions. The method involves the treatment of multiple presentations of the same item as a stochastic process, Le., a series of interrelated stochastic events. Some general results are presented and a particular model for practice effects utilizing the latent classes and linear operator learning models1 is discussed a t some length. Methods of parameter estimation and testing goodness of fit are presented and illustrated with a numerical example.