Assessing Patient Acceptance of an Automated Algorithm to Identify Ciswomen for HIV Pre-Exposure Prophylaxis

The use of HIV pre-exposure prophylaxis (PrEP) in cisgender women (ciswomen) lags far behind their need. Data elements from the electronic medical record (EMR), including diagnosis of a sexually transmitted infection (STI), can be incorporated into automated algorithms for identifying clients who are most vulnerable to HIV and would benefit from PrEP. However, it is unknown how women feel about the use of such technology. In this study, we assessed women's attitudes and opinions about an automated EMR-based HIV risk algorithm and determined if their perspectives varied by level of HIV risk. Respondents were identified using best practice alerts or referral to a clinic for STI symptoms from January to December 2021 in Chicago, IL. Participants were asked about HIV risk factors, their self-perceived HIV risk, and their thoughts regarding an algorithm to identify ciswomen who could benefit from PrEP. Most of the 112 women who completed the survey (85%) thought they were at low risk for HIV, despite high rates of STI diagnoses. The majority were comfortable with the use of this algorithm, but their comfort level dropped when asked about the algorithm identifying them specifically. Ciswomen had mixed feelings about the use of an automated HIV risk algorithm, citing it as a potentially helpful and empowering tool for women, yet raising concerns about invasion of privacy and potential racial bias. Clinics must balance the benefits of using an EMR-based algorithm for ciswomen with their concerns about privacy and bias to improve PrEP uptake among particularly vulnerable women.

Development of a predictive model for identifying women vulnerable to HIV in Chicago

INTRODUCTION

Researchers in the United States have created several models to predict persons most at risk for HIV. Many of these predictive models use data from all persons newly diagnosed with HIV, the majority of whom are men, and specifically men who have sex with men (MSM). Consequently, risk factors identified by these models are biased toward features that apply only to men or capture sexual behaviours of MSM. We sought to create a predictive model for women using cohort data from two major hospitals in Chicago with large opt-out HIV screening programs.

METHODS

We matched 48 newly diagnosed women to 192 HIV-negative women based on number of previous encounters at University of Chicago or Rush University hospitals. We examined data for each woman for the two years prior to either their HIV diagnosis or their last encounter. We assessed risk factors including demographic characteristics and clinical diagnoses taken from patient electronic medical records (EMR) using odds ratios and 95% confidence intervals. We created a multivariable logistic regression model and measured predictive power with the area under the curve (AUC). In the multivariable model, age group, race, and ethnicity were included a priori due to increased risk for HIV among specific demographic groups.

RESULTS

The following clinical diagnoses were significant at the bivariate level and were included in the model: pregnancy (OR 1.96 (1.00, 3.84)), hepatitis C (OR 5.73 (1.24, 26.51)), substance use (OR 3.12 (1.12, 8.65)) and sexually transmitted infections (STIs) chlamydia, gonorrhoea, or syphilis. We also a priori included demographic factors that are associated with HIV. Our final model had an AUC of 0.74 and included healthcare site, age group, race, ethnicity, pregnancy, hepatitis C, substance use, and STI diagnosis.

CONCLUSIONS

Our predictive model showed acceptable discrimination between those who were and were not newly diagnosed with HIV. We identified risk factors such as recent pregnancy, recent hepatitis C diagnosis, and substance use in addition to the traditionally used recent STI diagnosis that can be incorporated by health systems to detect women who are vulnerable to HIV and would benefit from preexposure prophylaxis (PrEP).

PrEP Persistence Support and Monitoring in Areas of High HIV Burden in the Midwestern United States

Monitoring pre-exposure prophylaxis (PrEP) metrics can guide service delivery yet does not occur routinely. We developed a survey to understand current practices for monitoring PrEP at PrEP-providing organizations in Illinois and Missouri. The survey was distributed from September through November 2020; 26 organizations participated. Most respondents indicated ongoing efforts to screen for PrEP eligibility (66.7%), link to care (87.5%), and retain clients in care (70.8%); 70.8% reported collecting data on PrEP initiation, 41.7% on retention in care, and 37.5% on missed visits. Barriers to monitoring PrEP metrics included lack of IT support (69.6%), manual processes (69.6%), and lack of staff resources (65.2%). Most respondents offered clients support for PrEP retention and adherence and wanted to expand interventions for PrEP persistence, yet fewer monitored corresponding metrics. To enhance PrEP implementation, organizations should improve monitoring and evaluation of PrEP metrics along the entire continuum and respond with appropriate services to support clients.

Predictive Modeling of Lapses in Care for People Living with HIV in Chicago: Algorithm Development and Interpretation

BACKGROUND

Reducing care lapses for people living with HIV is critical to ending the HIV epidemic and beneficial for their health. Predictive modeling can identify clinical factors associated with HIV care lapses. Previous studies have identified these factors within a single clinic or using a national network of clinics, but public health strategies to improve retention in care in the United States often occur within a regional jurisdiction (eg, a city or county).

OBJECTIVE

We sought to build predictive models of HIV care lapses using a large, multisite, noncurated database of electronic health records (EHRs) in Chicago, Illinois.

METHODS

We used 2011-2019 data from the Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN), a database including multiple health systems, covering the majority of 23,580 people with an HIV diagnosis living in Chicago. CAPriCORN uses a hash-based data deduplication method to follow people across multiple Chicago health care systems with different EHRs, providing a unique citywide view of retention in HIV care. From the database, we used diagnosis codes, medications, laboratory tests, demographics, and encounter information to build predictive models. Our primary outcome was lapses in HIV care, defined as having more than 12 months between subsequent HIV care encounters. We built logistic regression, random forest, elastic net logistic regression, and XGBoost models using all variables and compared their performance to a baseline logistic regression model containing only demographics and retention history.

RESULTS

We included people living with HIV with at least 2 HIV care encounters in the database, yielding 16,930 people living with HIV with 191,492 encounters. All models outperformed the baseline logistic regression model, with the most improvement from the XGBoost model (area under the receiver operating characteristic curve 0.776, 95% CI 0.768-0.784 vs 0.674, 95% CI 0.664-0.683; P<.001). Top predictors included the history of care lapses, being seen by an infectious disease provider (vs a primary care provider), site of care, Hispanic ethnicity, and previous HIV laboratory testing. The random forest model (area under the receiver operating characteristic curve 0.751, 95% CI 0.742-0.759) revealed age, insurance type, and chronic comorbidities (eg, hypertension), as important variables in predicting a care lapse.

CONCLUSIONS

We used a real-world approach to leverage the full scope of data available in modern EHRs to predict HIV care lapses. Our findings reinforce previously known factors, such as the history of prior care lapses, while also showing the importance of laboratory testing, chronic comorbidities, sociodemographic characteristics, and clinic-specific factors for predicting care lapses for people living with HIV in Chicago. We provide a framework for others to use data from multiple different health care systems within a single city to examine lapses in care using EHR data, which will aid in jurisdictional efforts to improve retention in HIV care.

Measuring Retention in HIV Care in the First Year of the COVID-19 Pandemic: The Impact of Telehealth

It is unknown how the COVID-19 pandemic impacted traditional measures of retention in HIV care. We calculated six different retention measures at an urban HIV care clinic for two time periods: pre-pandemic, and during the first year of the COVID-19 pandemic, with and without inclusion of telehealth appointments. Spearman rank correlation was used to assess correlation between different measures of retention. For both the pre-pandemic and pandemic time periods, there was strong correlation among measures of missed visits (range 0.857-0.957). More patients were considered retained in care during the pandemic when telehealth appointments were included in the analysis.

No-show Prediction Model Performance Among People With HIV: External Validation Study

BACKGROUND

Regular medical care is important for people living with HIV. A no-show predictive model among people with HIV could improve clinical care by allowing providers to proactively engage patients at high risk of missing appointments. Epic, a major provider of electronic medical record systems, created a model that predicts a patient's probability of being a no-show for an outpatient health care appointment; however, this model has not been externally validated in people with HIV.

OBJECTIVE

We examined the performance of Epic's no-show model among people with HIV at an academic medical center and assessed whether the performance was impacted by the addition of demographic and HIV clinical information.

METHODS

We obtained encounter data from all in-person appointments among people with HIV from January 21 to March 30, 2022, at the University of Chicago Medicine. We compared the predicted no-show probability at the time of the encounter to the actual outcome of these appointments. We also examined the performance of the Epic model among people with HIV for only HIV care appointments in the infectious diseases department. We further compared the no-show model among people with HIV for HIV care appointments to an alternate random forest model we created using a subset of seven readily accessible features used in the Epic model and four additional features related to HIV clinical care or demographics.

RESULTS

We identified 674 people with HIV who contributed 1406 total scheduled in-person appointments during the study period. Of those, we identified 331 people with HIV who contributed 440 HIV care appointments. The performance of the Epic model among people with HIV for all appointments in any outpatient clinic had an area under the receiver operating characteristic curve (AUC) of 0.65 (95% CI 0.63-0.66) and for only HIV care appointments had an AUC of 0.63 (95% CI 0.59-0.67). The alternate model we created for people with HIV attending HIV care appointments had an AUC of 0.78 (95% CI 0.75-0.82), a significant improvement over the Epic model restricted to HIV care appointments (P<.001). Features identified as important in the alternate model included lead time, appointment length, HIV viral load >200 copies per mL, lower CD4 T cell counts (both 50 to <200 cells/mm3 and 200 to <350 cells/mm3), and female sex.

CONCLUSIONS

For both models among people with HIV, performance was significantly lower than reported by Epic. The improvement in the performance of the alternate model over the proprietary Epic model demonstrates that, among people with HIV, the inclusion of demographic information may enhance the prediction of appointment attendance. The alternate model further reveals that the prediction of appointment attendance in people with HIV can be improved by using HIV clinical information such as CD4 count and HIV viral load test results as features in the model.

Trends in STI testing and diagnosis rates during the COVID-19 pandemic at a large urban tertiary care center, and the role of the emergency department in STI care

Introduction

The COVID-19 pandemic has had profound effects on access to care, including outpatient sexually transmitted infection (STI) testing and treatment. Many vulnerable populations already relied on the emergency department (ED) for much of their care prior to the pandemic. This study examines trends in STI testing and positivity before and during the pandemic at a large urban medical center and evaluates the role of the ED in providing STI care.

Methods

This is a retrospective review of all gonorrhea, chlamydia, and trichomonas tests from November 1, 2018, through July 31, 2021. Demographic information and location and results of STI testing were extracted from the electronic medical record. Trends in STI testing and positivity were examined for 16 month periods before and after the COVID-19 pandemic started (March 15, 2020), with the latter divided into the early pandemic period (EPP: March 15 -July 31, 2020) and late pandemic period (LPP: August 1, 2020 - July 31, 2021).

Results

Tests per month decreased by 42.4% during the EPP, but rebounded by July 2020. During the EPP, the proportion of all STI testing originating in the ED increased from 21.4% pre-pandemic to 29.3%, and among pregnant women from 45.2% to 51.5%. Overall STI positivity rate increased from 4.4% pre-pandemic to 6.2% in the EPP. Parallel trends were observed for gonorrhea and chlamydia individually. The ED represented 50.5% of overall positive tests, and as much as 63.1% of positive testing during the EPP. The ED was the source of 73.4% of positive tests among pregnant women, which increased to 82.1% during the EPP.

Conclusions

STI trends from this large urban medical center paralleled national trends, with an early decrease in positive cases followed by a rebound by the end of May 2020. The ED represented an important source of testing for all patients, and especially for pregnant patients, throughout the study period, but even more so early in the pandemic. This suggests that more resources should be directed towards STI testing, education, and prevention in the ED, as well as to support linkage to outpatient primary and obstetric care during the ED visit.

Comparison of algorithms for identifying people with HIV from electronic medical records in a large, multi-site database

Objective

As electronic medical record (EMR) data are increasingly used in HIV clinical and epidemiologic research, accurately identifying people with HIV (PWH) from EMR data is paramount. We sought to evaluate EMR data types and compare EMR algorithms for identifying PWH in a multicenter EMR database.

Materials and Methods

We collected EMR data from 7 healthcare systems in the Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN) including diagnosis codes, anti-retroviral therapy (ART), and laboratory test results.

Results

In total, 13 935 patients had a positive laboratory test for HIV; 33 412 patients had a diagnosis code for HIV; and 17 725 patients were on ART. Only 8576 patients had evidence of HIV-positive status for all 3 data types (laboratory results, diagnosis code, and ART). A previously validated combination algorithm identified 22 411 patients as PWH.

Conclusion

EMR algorithms that combine laboratory results, administrative data, and ART can be applied to multicenter EMR data to identify PWH.

Critical transitions in Chinese dunes during the past 12,000 years

Dune systems can have alternative stable states that coexist under certain environmental conditions: a vegetated, stabilized state and a bare active state. This behavior implies the possibility of abrupt transitions from one state to another in response to gradual environmental change. Here, we synthesize stratigraphic records covering 12,000 years of dynamics of this system at 144 localities across three dune fields in northern China. We find side-by-side coexistence of active and stabilized states, and occasional sharp shifts in time between those contrasting states. Those shifts occur asynchronously despite the fact that the entire landscape has been subject to the same gradual changes in monsoon rainfall and other conditions. At larger scale, the spatial heterogeneity in dune dynamics averages out to produce relatively smooth change. However, our results do show different paths of recovery and collapse of vegetation at system-wide scales, implying that hysteretic behavior occurs in spatially extended systems.

Australian multicentre study of current real-world prophylaxis practice in severe and moderate haemophilia A and B

INTRODUCTION

With the emergence of novel treatment products for haemophilia and an increasing focus on the benefits of pharmacokinetic driven individualized prophylaxis, robust national data with regard to current patterns of factor consumption and adherence are required.

AIM

To characterize current Australian practice with regard to use of prophylactic clotting factor infusions in patients with moderate or severe haemophilia A (HA) and haemophilia B (HB).

METHODS

This was a retrospective, non-interventional study utilizing Australian Bleeding Disorder Registry (ABDR) data collected over a 12 month period. Registered and consented patients with moderate or severe HA or HB without inhibitors were included.

RESULTS

A total of 718 HA (551 severe, 167 moderate) and 166 HB (87 severe, 79 moderate) patients were included. Regular prophylaxis was prescribed in 453 patients (82%) with severe HA, 42 patients (25%) with moderate HA, 66 patients (75%) with severe HB and 11 patients (14%) with moderate HB. Near universal prophylaxis was achieved in the paediatric subgroup. The mean weekly dose of factor VIII in severe HA was 84 international units/kg/wk (IU/kg/wk) vs 71 IU/kg/wk of factor IX in severe HB. Most patients on prophylaxis were treated ≥3 times/wk (HA) or 2 times/wk (HB). Non-adherence peaked in the 20-29 year age group. Older individuals on regular prophylaxis used more factor than was expected for their prescribed regimen.

CONCLUSION

Prophylaxis rates in severe haemophilia are comparable with other developed nations. The benefit of a national registry is demonstrable. Furthermore research into the underlying reasons for non-compliance in young adults with haemophilia is required.

Assessment and validation of a defined fluid restriction protocol in the use of subcutaneous desmopressin for children with inherited bleeding disorders

INTRODUCTION

Despite the availability of subcutaneous desmopressin (1-deamino-8-d-arginine vasopressin, SC-DDAVP) as a haemostatic agent for children with mild bleeding disorders, few publications specifically address the safety or efficacy of this mode of administration.

AIM

Our aim was to assess whether a defined fluid restriction protocol was effective in preventing hyponatremia in children receiving perioperative SC-DDAVP, and to document adequate biological and clinical response in this setting.

METHODS

We retrospectively analysed a cohort of children with mild bleeding disorders prescribed SC-DDAVP over a 5-year period following institution of a 'two-thirds maintenance' fluid restriction protocol.

RESULTS

Sixty-nine patients received SC-DDAVP following this protocol, including 15 with mild haemophilia A, 49 with von Willebrand disease (VWD) and five with platelet storage pool disorder. In patients who underwent formal preoperative assessment a complete or partial response was observed in 28/29 with type 1 VWD and 14/15 with mild haemophilia A. Perioperative SC-DDAVP provided excellent haemostasis in all patients, with no requirement for factor concentrate or blood products. Mild asymptomatic hyponatremia was detected in seven children who received multiple doses of DDAVP (lowest sodium 129 mmol L(-1) ); however, adherence to the prescribed fluid restriction protocol was questionable in six of these cases. Symptomatic hyponatremia was not observed.

CONCLUSION

Subcutaneous desmopressin was well-tolerated, with no serious side-effects observed, and good biological responses in preoperative trials. A two-thirds maintenance fluid regimen was effective at preventing symptomatic hyponatremia in our cohort, and is now the standard protocol for fluid restriction post-DDAVP administration in our centre.

Oncogenic Ras differentially regulates metabolism and anoikis in extracellular matrix-detached cells

In order for cancer cells to survive during metastasis, they must overcome anoikis, a caspase-dependent cell death process triggered by extracellular matrix (ECM) detachment, and rectify detachment-induced metabolic defects that compromise cell survival. However, the precise signals used by cancer cells to facilitate their survival during metastasis remain poorly understood. We have discovered that oncogenic Ras facilitates the survival of ECM-detached cancer cells by using distinct effector pathways to regulate metabolism and block anoikis. Surprisingly, we find that while Ras-mediated phosphatidylinositol (3)-kinase signaling is critical for rectifying ECM-detachment-induced metabolic deficiencies, the critical downstream effector is serum and glucocorticoid-regulated kinase-1 (SGK-1) rather than Akt. Our data also indicate that oncogenic Ras blocks anoikis by diminishing expression of the phosphatase PHLPP1 (PH Domain and Leucine-Rich Repeat Protein Phosphatase 1), which promotes anoikis through the activation of p38 MAPK. Thus, our study represents a novel paradigm whereby oncogene-initiated signal transduction can promote the survival of ECM-detached cells through divergent downstream effectors.

Selective thermal emission from patterned steel

Patterned metal films have been shown to possess unique optical properties resulting from the excitation of surface plasmon polaritons at the patterned metal surface. Here we demonstrate spectrally selective thermal emission from patterned steel substrates. The materials and processes used in this work were chosen for their potential scalability to large-area and low cost production of metal films with distinct and designable thermal signatures. The samples studied were characterized by reflection and emission spectroscopy, and a factor of 2.6 emission enhancement is demonstrated for the design wavelength. These results are compared to numerical simulations.

The clinical characterisation of systemic lupus erythematosus in a Far North Queensland Indigenous kindred

The aetiology of systemic lupus erythematosus (SLE) is thought to involve both genetic and environmental factors. In other complex diseases, analysis of large multi-case families has resulted in insights into biological mechanisms. We have sought to characterise the members of an extended Indigenous family, five of whom have been diagnosed with SLE. Pedigree members were evaluated using the Lupus Screening Questionnaire, clinical interviews and medical records. Participants contributed blood and urine samples for laboratory analysis. A Mendelian pattern of inheritance was not observed. The five affected members (all female) shared two American College of Rheumatology criteria (positive ANA and arthritis) but showed a wide variety of other SLE manifestations. Disease onset, severity and progression were discordant. Including the five individuals with SLE, 15 blood relatives and two non-consanguineous spouses had autoimmune manifestations. Autoimmune haemolytic anaemia (one case), idiopathic thrombocytopenic purpura (ITP) (one case) and hypothyroidism (two cases) were observed in non-SLE affected individuals. Anti-nuclear antibodies were present in 12 blood relatives and one non-consanguineous spouse. Infections (especially of the skin) were observed to be common in the kindred. The lack of clear Mendelian inheritance or phenotypic concordance makes a rare monogenic explanation for SLE unlikely in this family. The finding of familial autoimmunity associated with SLE further supports the hypothesis that a common genetic pathway can precipitate autoimmunity, with further genes and possible environmental factors interacting to produce the eventual phenotype. Future genetic linkage studies may reveal a rare ‘autoimmune gene’ variant in this kindred.

Large Wind Shift on the Great Plains During the Medieval Warm Period

Spring-summer winds from the south move moist air from the Gulf of Mexico to the Great Plains. Rainfall in the growing season sustains prairie grasses that keep large dunes in the Nebraska Sand Hills immobile. Longitudinal dunes built during the Medieval Warm Period (800 to 1000 years before the present) record the last major period of sand mobility. These dunes are oriented NW-SE and are composed of cross-strata with bipolar dip directions. The trend and structure of the dunes record a drought that was initiated and sustained by a historically unprecedented shift of spring-summer atmospheric circulation over the Plains: Moist southerly flow was replaced by dry southwesterly flow.

Undiagnosed bleeding states and medical treatment

Relatively little attention has been placed in mild hemophilia in the orthopedic literature even though there are probably an equal number of patients with mild as compared to classic manifestations. Mild hemophilia and similar related conditions frequently are undiagnosed and may represent major problems and if associated with surgery, catastrophic results. Patients with milder bleeding diatheses may not have a diagnosis made until late in life. Mild hemophilia and hemophiloid conditions are defined and typical findings are given. Other causes of intra or postoperative hemorrhagic states are mentioned. Three case reports of mild Factor VIII and Factor XI deficiency, undiagnosed prior to the author's medical treatment, are presented. Knowledge of the typical historical findings, diagnostic methods, and proper treatment of patients seeking medical treatment with mild hemophilia, hemophiloid and similar conditions explaining hemorrhage following trauma and intra and postoperatively will help to prevent undesirable results as well as severe complications.

Lethal Sandslides from Eolian Dunes

Fossil vertebrates entombed within the Upper Cretaceous Djadokhta Formation of southern Mongolia bear testimony to a heretofore unknown geologic phenomenon: mass wasting of eolian dunes during heavy rainstorms. Evaporation of shallow-penetrating rainwater led to progressive calcite accumulation in a thin layer of sand about 0.5 m below the surface of dune lee slopes. During rare heavy rainstorms, a perched water table developed at the top of calcitic zones. Positive pore water pressure led to translational slides and fast-moving sediment gravity flows that overwhelmed animals on the lee slopes of large dunes and in interdune areas.

Universal infant hearing screening by automated auditory brainstem response measurement

BACKGROUND

Our purpose was to identify infants with a bilateral, permanent, handicapping hearing loss and to provide them with amplification before age 6 months.

METHODOLOGY

The study population consisted of 10,372 infants born during a 5-year period. Universal hearing screening by automated auditory brainstem response was done in the nursery. Infants who failed the screening test were followed up diagnostically. Infants who were not tested in the nursery were followed up as outpatients. Hearing aids were recommended for those infants who had bilateral hearing loss.

RESULTS

Successful screening in the nursery was achieved for 96% of infants. The failure rate was 4%. The incidence of bilateral loss requiring amplification was 1.4/1000. The false-positive rate was 3.5% after the initial screening and .2% when a two-stage screening procedure was used. The incidence of congenital bilateral hearing loss in the well population was 1/1000, and in the neonatal intensive care unit population, 5/1000. The cost of screening was $17 per infant, and the cost to identify each true bilateral hearing loss was $17,750. Amplification was recommended for 15 infants; well infants who used hearing aids before age 6 months achieved age-appropriate speech and language development.

CONCLUSIONS

Mild, moderate, and severe bilateral, persistent hearing loss can be identified in the nursery by automated auditory brainstem response measurement to provide amplification before age 6 months and thus optimize speech and language development.

Isolation of nuclei for chromatin analysis in fission yeast

The methods available for analysis of the chromatin of Schizosaccharomyces pombe are time consuming (>8 h) and/or result in some degradation of the chromatin. Here we report an optimised method for the preparation of spheroplasts and the isolation of nuclei which takes <25 min and is suitable for analysis of chromatin structure by micrococcal nuclease, restriction endonuclease or by immunoprecipitation.

Effects of structured cooperative contact on changing negative attitudes toward stigmatized social groups

The contact hypothesis predicts that cooperative interaction with members of a disliked group results in increased liking for those members and generalizes to more positive attitudes toward the group. The authors sought to provide evidence consistent with the hypothesis that contact affects attitude in part by eliciting a more positive portrait of the typical group member. Undergraduates participated in a 1-hr dyadic learning session (scripted cooperative learning, jigsaw cooperative learning, or individual study) with a confederate portrayed as a former mental patient. Students initially expected the confederate to display traits similar to those of a typical former mental patient. After the sessions, initially prejudiced students in the 2 cooperative conditions described the typical mental patient more positively and adopted more positive attitudes and wider latitudes of acceptance toward the group. Connections between intergroup attitudes and impression formation are discussed.

Effects of structured cooperative contact on changing negative attitudes toward stigmatized social groups

The contact hypothesis predicts that cooperative interaction with members of a disliked group results in increased liking for those members and generalizes to more positive attitudes toward the group. The authors sought to provide evidence consistent with the hypothesis that contact affects attitude in part by eliciting a more positive portrait of the typical group member. Undergraduates participated in a 1-hr dyadic learning session (scripted cooperative learning, jigsaw cooperative learning, or individual study) with a confederate portrayed as a former mental patient. Students initially expected the confederate to display traits similar to those of a typical former mental patient. After the sessions, initially prejudiced students in the 2 cooperative conditions described the typical mental patient more positively and adopted more positive attitudes and wider latitudes of acceptance toward the group. Connections between intergroup attitudes and impression formation are discussed.

Methodological variables affecting phonational frequency range in adults

This study examined the effects of selected elicitation variables on phonational frequency (Fo) range in normal adults. Twenty men and 20 women responded to five audiotaped tone conditions: (a) discrete steps, (b) slow steps, (c) fast steps, (d) slow glissando, and (e) fast glissando. These stimuli were devised to elicit each person's maximal and minimal Fo. All elicitation conditions evoked a significantly higher maximal Fo and a significantly larger Fo range (in both hertz and semitones) than did the discrete-steps condition. Fast steps produced a significantly higher minimal Fo than did fast glissando. Both slow glissando and fast glissando yielded a significantly larger Fo range in semitones than did fast steps. Finally, the women demonstrated a significantly larger Fo range (in hertz but not semitones) than did the men.

Factors influencing fundamental frequency range estimates in children

Selected elicitation conditions were manipulated to determine their effect on fundamental frequency (Fo) range estimates in children. Forty normal children each responded to five autiotaped tone conditions: (a) discrete steps, (b) slow steps, (c) fast steps, (d) slow glissando, and (e) fast glissando. These tonal stimuli were devised to elicit each child's maximal and minimal Fo. The traditional discrete-steps condition was associated with a lower maximal Fo, higher minimal Fo, and a more restricted Fo range than all other conditions.

Spinal fusion for chronic low back pain

Results of spinal fusion for chronic low back pain in 46 patients are analyzed, and the authors set forth the clinical circumstances in which the procedure may relieve this common complaint.

Immature stages of Trichonema spp as a cause of diarrhoea in adult horses in spring

Several incidents of diarrhoea and loss of weight occurred in adult horses during the spring of 1976. Detailed investigation of one typical case suggested that maturation of inhibited larvae of Trichonema spp was responsible.

Vascular and adjacent soft tissue injuries associated with fractures of the pelvis

One hundred fifty-one patients with fractures of the pelvis and associated injuries have been reviewed. Patients who have these injuries are likely to have uncontrollable, fatal hemorrhage. Of this group, nine died, 11 had exploratory laparotomies, ten had bladder injuries, and two had rectal damage. Blood gas determinations, arterial catheterization, and pulmonary wedge pressure determinations are valuable in making and early diagnosis of pathologic changes resulting from internal hemorrhage.