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Fungi are important decomposers of organic material, including animal waste. Ammonia and postputrefaction fungi grow in soil enriched in ammonium and nitrogen from carcasses. In 2014, we observed mushrooms fruiting on the flesh of a dead muskrat (Ondatra zibethicus) in an abandoned underground copper mine in southeastern New Brunswick, Canada. We placed an adult beaver (Castor canadensis) carcass near the muskrat to facilitate fungal colonization and fruiting. The beaver carcass was colonized by a variety of molds, especially Acaulium caviariforme. We observed mushrooms of an unidentified copriniid on the flesh 6 years and 9 months after carcass placement. Using morphological and molecular (nuclear internal transcribed spacer [nrITS]) data, we identified the mushrooms as Coprinopsis laanii, a rarely encountered species generally considered lignicolous. We discuss the role of C. laanii, and other postputrefaction fungi, in cave environments.

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BACKGROUND: The COVID-19 pandemic is placing abnormally high and ongoing demands on healthcare systems. Little is known about the full effect of the COVID-19 pandemic on diseases other than COVID-19 in the South African setting. OBJECTIVE: To describe a cohort of hospitalised patients under investigation for SARS-CoV-2 that initially tested negative. METHODS: Consecutive patients hospitalised at Khayelitsha Hospital from April to June 2020, whose initial polymerase chain reaction test for SARS-CoV-2 was negative were included. Patient demographics, clinical characteristics, ICD-10 (International Statistical Classification of Diseases and Related Health Problems 10th Revision) diagnosis, referral to tertiary level facilities and ICU, and all-cause in-hospital mortality were collected. The 90-day re-test rate was determined and comparisons were made using the χ2-test and the independent samples median test. RESULTS: Overall, 261 patients were included: median age 39.8 years, 55.6% female (n = 145). Frequent comorbidities included HIV (41.4%), hypertension (26.4%), and previous or current tuberculosis (24.1%). Nine (3.7%) patients were admitted to ICU and 38 (15.6%) patients died. Ninety-three patients (35.6%) were re-tested and 21 (22.6%) were positive for SARS-CoV-2. The top primary diagnoses related to respiratory diseases (n = 82, 33.6%), and infectious and parasitic diseases (n = 62, 25.4%). Thirty-five (14.3%) had a COVID-19 diagnostic code assigned (26 without microbiological confirmation) and 43 (16.5%) had tuberculosis. Older age (p = 0.001), chronic renal impairment (p = 0.03) and referral to higher level of care (all p < 0.001; ICU p = 0.03) were more frequent in those that died. CONCLUSION: Patients with tuberculosis and other diseases are still presenting to emergency centres with symptoms that may be attributable to SARS-CoV-2 and requiring admission. Extreme vigilance will be necessary to diagnosis and treat tuberculosis and other diseases as we emerge from the COVID-19 pandemic.

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Many neurons adapt their spike output to accommodate the prevailing sensory environment. Although such adaptation is thought to improve coding of relevant stimulus features, the relationship between adaptation at the neural and behavioral levels remains to be established. Here we describe improved discrimination performance for an auditory spatial cue (interaural time differences, ITDs) following adaptation to stimulus statistics. Physiological recordings in the midbrain of anesthetized guinea pigs and measurement of discrimination performance in humans both demonstrate improved coding of the most prevalent ITDs in a distribution, but with highest accuracy maintained for ITDs corresponding to frontal locations, suggesting the existence of a fovea for auditory space. A biologically plausible model accounting for the physiological data suggests that neural tuning is stabilized by inhibition to maintain high discriminability for frontal locations. The data support the notion that adaptive coding in the midbrain is a key element of behaviorally efficient sound localization in dynamic acoustic environments.

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We report a systematic relationship between sound-frequency tuning and sensitivity to interaural time delays for neurons in the midbrain nucleus of the inferior colliculus; neurons with relatively low best frequencies (BFs) showed response peaks at long delays, whereas neurons with relatively high BFs showed response peaks at short delays. The consequence of this relationship is that the steepest region of the function relating discharge rate to interaural time delay (ITD) fell close to midline for all neurons irrespective of BF. These data provide support for a processing of the output of coincidence detectors subserving low-frequency sound localization in which the location of a sound source is determined by the activity in two broad, hemispheric spatial channels, rather than numerous channels tuned to discrete spatial positions.

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BACKGROUND: Many believe that managed care creates pressure on physicians to increase productivity, see more patients, and spend less time with each patient. METHODS: We used nationally representative data from the National Ambulatory Medical Care Survey (NAMCS) of the National Center for Health Statistics and the American Medical Association's Socioeconomic Monitoring System (SMS) to examine the length of office visits with physicians from 1989 through 1998. We assessed the trends for visits covered by a managed-care or other prepaid health plan (prepaid visits) and non-prepaid visits for primary and specialty care, for new and established patients, and for common and serious diagnoses. RESULTS: Between 1989 and 1998 the number of visits to physicians' offices increased significantly from 677 million to 797 million, although the rate of visits per 100 population did not change significantly. The average duration of office visits in 1989 was 16.3 minutes according to the NAMCS and 20.4 minutes according to the SMS survey. According to both sets of data, the average duration of visits increased by between one and two minutes between 1989 and 1998. The duration of the visits increased for both prepaid and nonprepaid visits. Nonprepaid visits were consistently longer than prepaid visits, although the gap declined from 1 minute in 1989 to 0.6 minute in 1998. There was an upward trend in the length of visits for both primary and specialty care and for both new and established patients. The average length of visits remained stable or increased for patients with the most common diagnoses and for those with the most serious diagnoses. CONCLUSIONS: Contrary to expectations, the growth of managed health care has not been associated with a reduction in the length of office visits. The observed trends cannot be explained by increases in physicians' availability, shifts in the distribution of physicians according to sex, or changes in the complexity of the case mix.

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The utility of medical records and clinician reports for assessing substance abuse among inpatients with schizophrenia or schizoaffective disorder was assessed in a sample of 296 patients recruited from four general hospitals in New York City. Measures derived from the medical record, the discharge summary, and primary clinician reports are compared to the results of a structured diagnostic interview. Analysis of the sensitivity, specificity, positive predictive value, and overall accuracy of the nondiagnostic sources found unexpectedly high levels of detection. Discharge summaries had the lowest sensitivity when compared to the diagnostic interview, raising concern that inpatient staff and clinicians may fail to communicate substance abuse problems to outpatient providers.

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We examined responses from 91 single-neurons in the inferior colliculus (IC) of anesthetized guinea pigs to auditory apparent motion in the free field. Apparent motion was generated by presenting 100-ms tone bursts, separated by 50-ms silent intervals, at consecutive speaker positions in an array of 11 speakers, positioned in an arc +/-112.5 degrees around midline. Most neurons demonstrated discrete spatial receptive fields (SRFs) to apparent motion in the clockwise and anti-clockwise directions. However, SRFs showed marked differences for apparent motion in opposite directions. In virtually all neurons, mean best azimuthal positions for SRFs to opposite directions occurred at earlier positions in the motion sweep, producing receptive fields to the two directions of motion that only partially overlapped. Despite this, overall spike counts to the two directions were similar for equivalent angular velocities. Responses of 28 neurons were recorded to stimuli with different duration silent intervals between speaker presentations, mimicking different apparent angular velocities. Increasing the stimulus OFF time increased neuronal discharge rates, particularly at later portions of the apparent motion sweep, and reduced the differences in the SRFs to opposite motion directions. Consequently SRFs to both directions broadened and converged with decreasing motion velocity. This expansion was most obvious on the outgoing side of the each SRF. Responses of 11 neurons were recorded to short (90 degrees ) partially overlapping apparent motion sweeps centered at different spatial positions. Nonoverlapping response profiles were recorded in 9 of the 11 neurons tested and confirmed that responses at each speaker position were dependent on the preceding response history. Together these data are consistent with the suggestion that a mechanism of adaptation of excitation contributes to the apparent sensitivity of IC neurons to auditory motion cues. In addition, the data indicate that the sequential activation of an array of speakers to produce apparent auditory motion may not be an optimal stimulus paradigm to separate the temporal and spatial aspects of auditory motion processing.

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Convergent input from cells in the medial superior olive (MSO) and lateral superior olive (LSO) onto a single inferior colliculus (IC) cell explains many findings that are not compatible with a simple coincidence detector mechanism. Here this explanation is tested using a physiologically accurate computer model of the binaural pathway in which the input to the IC cell is either from two MSO cells or a MSO and a LSO cell. Auditory nerve (AN) spike trains are formed by a stochastic hair cell model following a basilar membrane simulation using a gammatone filter. In subsequent cells input spikes cause post-synaptic potentials (PSPs) which are summed causing the cell to fire when the sum crosses a threshold. The individual cells are matched to the physiology by varying the number of inputs, the magnitude and duration of the PSPs and the firing threshold. Non-linear best-phase-versus-frequency functions arise if the two IC inputs have different best frequencies and different characteristic delays. One input can be selectively suppressed by turning on an additional tone at the worst phase of that input. Non-zero characteristic phases arise if the characteristic frequencies of the AN fibres feeding into a single superior olive cell are mismatched.

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OBJECTIVE: The substantial failure of psychiatric patients to engage in outpatient specialty mental health care after an acute hospitalization at a time when managed care companies and others increasingly hold hospitals accountable for outcomes underscores the importance of identifying patients at high risk for not completing referrals. This study explored patient risk factors for not completing referrals and examined the success of several interventions targeted to achieving linkage with outpatient care. METHOD: A clinically detailed, structured form was used in abstracting information from the medical records of 229 inpatients with a primary psychiatric diagnosis. Clinicians and staff at outpatient programs were contacted to determine whether patients completed their referrals. RESULTS: Approximately two-thirds (65%) of the patients failed to attend scheduled or rescheduled initial outpatient mental health appointments after a hospital discharge. At high risk for unsuccessful linkage to outpatient care were patients with a persistent mental illness and those who had no prior public psychiatric hospitalization, were admitted involuntarily, and had longer lengths of stay. Controlling for risk factors, three clinical interventions used during the hospital stay more than tripled the odds of successful linkage to outpatient care: communication about patients' discharge plans between inpatient staff and outpatient clinicians, patients' starting outpatient programs before discharge, and family involvement during the hospital stay. CONCLUSIONS: Effective clinical bridging strategies can be used to avoid unnecessary gaps in the delivery of psychiatric services. Incorporating these strategies into routine care would enhance continuity of care, especially for some high-risk patients.

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We have measured the responses of inferior colliculus neurons in the anesthetized guinea pig to signals which in human psychophysical experiments reveal a release of masking as a result of binaural processing (the binaural masking level difference: BMLD). More specifically we have used diotic tones at 500 Hz (So) masked by noise that is either identical at the two ears (No) or inverted in one ear (Npi). This combination of signals and noise maskers produces a prominent masking release in humans such that the So signal is about 6-12 dB more detectable in the presence of the Npi noise than the No noise. Low-frequency inferior colliculus neurons are sensitive to the interaural delay of the masking noise and generally respond most to the components nearest their best frequency. Since most inferior colliculus neurons have peaks in their delay functions close to zero interaural time delay this means that while No noise is effective in driving the unit, Npi noise is much less effective. As the level of an So tone was progressively increased in the presence of No and Npi noises, the first response could be either an increase or a decrease in the activity due to the noise. However, because Npi generated little or no activity itself, the predominant response to the So tone was an increase in discharge in this condition. Masked thresholds were defined as the point at which the standard separation D (related to the d' of signal detection theory) = 1 in either direction. BMLDs were measured in single neurons and in the majority of units were in a direction consistent with the psychophysical observations irrespective of the direction of the discharge rate change that occurred at threshold. The lowest masked thresholds always occurred at or near the signal frequency of 500 Hz. An average value of the single unit BMLD around 500 Hz was 3.6 dB (NoSo vs. NpiSo) compared with 6.6 dB for the NoSo versus NoSpi BMLD we had previously reported. This lower magnitude is consistent with the hierarchy of human psychophysical BMLDs.

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OBJECTIVE: The authors examine patterns in utilization of psychiatric inpatient services by children and adolescents in general hospitals during 1988-1995. METHOD: National Hospital Discharge Survey data were used to describe utilization patterns for children and adolescents with primary psychiatric diagnoses in general hospitals from 1988 to 1995. RESULTS: During the study period, there was a 36% increase in hospital discharges and a 44% decline in mean length of stay, resulting in a 23% decline in the number of bed-days, from more than 3 million to about 2.5 million. The number of nonpsychotic major depressive disorders increased significantly. Discharges from public hospitals have declined, and those from proprietary hospitals have risen. Concurrently, the role of private insurance declined and the role of Medicaid increased. During the period of study, the mean and median length of stay declined most for children and adolescents who were hospitalized in private facilities and those covered by private insurance. Across the United States, the mean length of stay declined significantly; this decline was almost 60% in the West. Discharges also declined in the West, in contrast to the Midwest and the South, where they significantly increased. CONCLUSIONS: Increased numbers of discharges and decreased length of stay may reflect evolving market forces and characteristics of hospitals. Further penetration by managed care into the public insurance system or modifications in existing Medicaid policy could have a profound impact on the availability of inpatient resources.

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BACKGROUND: While widely acknowledged to be an important clinical and public health issue, HIV assessment, counseling, and testing for the seriously mentally ill has not been well studied. OBJECTIVE: To determine what proportion and which inpatients with schizophrenia have been recently tested for HIV. METHOD: A sample of 300 inpatients with schizophrenia were recruited from four general hospitals in New York City over a one year period. After confirmation of diagnosis with a structured interview, and elicitation of sociodemographic and drug use information, medical record review identified recent HIV testing. Bivariate and multivariate analyses were used to identify subgroups more likely to be tested. FINDINGS: Recent HIV testing had been performed for 17% of the sample and was concentrated among those with higher documented risks. The majority of patients remain untested even in groups with direct risks, such as injection drug use, and indirect risks, such as frequent cocaine use in last year. Some evidence was found that white patients at risk may be less likely to be tested than Hispanic or African American patients. CONCLUSIONS: Aggressive efforts are needed to improve knowledge of HIV status among acutely ill patients with schizophrenia.

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BACKGROUND: Patient Outcomes Research Team treatment recommendations were used to investigate the relationship between patient characteristics and higher-than-recommended dosages (> 1000 chlorpromazine equivalents [CPZe]) at discharge. METHOD: Inpatients who met the DSM-IV criteria for schizophrenia or schizoaffective disorder were recruited from 4 general hospitals. For those patients (N = 293) prescribed antipsychotics at discharge, chi-square tests and multiple regression analyses were used to assess the relationship between demographics, admission characteristics, comorbid diagnoses, and antipsychotic dosages. The relationship between clinical symptoms and antipsychotic dosage at discharge was also examined. RESULTS: Antipsychotic dosages conformed to treatment guidelines for approximately 65% of patients; 21% received doses in excess of recommended levels. African American patients and those with a history of psychiatric hospitalization were more likely to be prescribed discharge antipsychotic doses greater than 1000 CPZe. Hospital differences in antipsychotic management were also observed. Regression analyses indicated that higher-than-recommended dosages found among African American patients could not be explained by differences in symptom levels at discharge. Patients with more thought disorder were also more likely to be prescribed antipsychotic dosages in excess of the recommended range. Compared with oral administration, depot administration increased the risk of excess dosage by a factor of 30. Controlling for method of administration reduced the impact of race to nonsignificance. CONCLUSION: These results replicate earlier findings that minority individuals are more likely to be prescribed dosages in excess of the recommended range and suggest that this pattern is due to higher use of depot injection in African American patients. Further research should examine how patient characteristics and institutional factors influence medication use.

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OBJECTIVE: To examine the sociodemographic, need, risk, and insurance characteristics of persons with severe mental illness and the importance of these characteristics for predicting specialty mental health utilization among this group. DATA SOURCE: The Healthcare for Communities survey, a national study that tracks alcohol, drug, and mental health services utilization. Data come from a telephone survey of adults from 60 communities across the United States, and from a supplemental geographically dispersed sample. STUDY DESIGN: Respondents were categorized as having a severe mental disorder, other mental disorder, or no measured mental disorder. Differences among groups in sociodemographics (gender, marital status, race, education, and income), insurance coverage, need for mental health care (symptoms and perceived need), and risk indicators (suicide ideation, criminal involvement, and aggressive behavior) are examined. Measures of service use for mental health care include emergency room, inpatient, and specialty outpatient care. The importance of sociodemographics, need, insurance status, and risk indicators for specialty mental health care utilization are examined through logistic regression. PRINCIPAL FINDINGS: The severely mentally ill in this study are disproportionately African American, unmarried, male, less educated, and have lower family incomes than those with other disorders and those with no measured mental disorders. In a 12-month period almost three-fifths of persons with severe mental illness did not receive specialty mental health care. One in five persons with severe mental illness are uninsured, and Medicare or Medicaid insures 37 percent. Persons covered by these public programs are over six times more likely to have access to specialty care than the uninsured are. Involvement in the criminal justice system also increases the probability that a person will receive care by a factor of about four, independent of level of need. The average number of outpatient visits for specialty care varies little across type of disorder, and the median number of visits (ten) is equivalent for those with a severe mental illness and those with other disorders. CONCLUSIONS: Persons with severe mental illness have a high level of economic and social disadvantage. Barriers to care, including lack of insurance, are substantial and many do not receive specialty care. Public insurance programs are the major points of leverage for improving access, and policy interventions should be targeted to these programs. Problems of adequate care for the severely mentally ill may be exacerbated by the managed care trend to reductions in intensity of treatment.

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Responses to sound stimuli that humans perceive as moving were obtained for 89 neurons in the inferior colliculus (IC) of urethan-anesthetized guinea pigs. Triangular and sinusoidal interaural phase modulation (IPM), which produced dynamically varying interaural phase disparities (IPDs), was used to present stimuli with different depths, directions, centers, and rates of apparent motion. Many neurons appeared sensitive to dynamic IPDs, with responses at any given IPD depending strongly on the IPDs the stimulus had just passed through. However, it was the temporal pattern of the response, rather than the motion cues in the IPM, that determined sensitivity to features such as motion depth, direction, and center locus. IPM restricted only to the center of the IPD responsive area, evoked lower discharge rates than when the stimulus either moved through the IPD responsive area from outside, or up and down its flanks. When the stimulus was moved through the response area first in one direction and then back in the other, and the same IPDs evoked different responses, the response to the motion away from the center of the IPD responsive area was always lower than the response to the motion toward the center. When the IPD was closer at which the direction of motion reversed was to the center, the response to the following motion was lower. In no case did we find any evidence for neurons that under all conditions preferred one direction of motion to the other. We conclude that responses of IC neurons to IPM stimuli depend not on the history of stimulation, per se, but on the history of their response to stimulation, irrespective of the specific motion cues that evoke those responses. These data are consistent with the involvement of an adaptation mechanism that resides at or above the level of binaural integration. We conclude that our data provide no evidence for specialized motion detection involving dynamic IPD cues in the auditory midbrain of the mammal.

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OBJECTIVE: The study examined patterns of care for persons with mental illness in nursing homes in the United States from 1985 to 1995. During that period resident populations in public mental hospitals declined, and legislation aimed at diverting psychiatric patients from nursing homes was enacted. METHODS: Estimates of the number of current residents with a mental illness diagnosis and those with a severe mental illness were derived from the 1985 and 1995 National Nursing Home Surveys and the 1987 and 1996 Medical Expenditure Surveys. Trends by age group and changes in the mentally ill population over this period were assessed. RESULTS: The number of nursing home residents diagnosed with dementia-related illnesses and depressive illnesses increased, but the number with schizophrenia-related diagnoses declined. The most substantial declines occurred among residents under age 65; more than 60 percent fewer had any primary psychiatric diagnosis or severe mental illness. CONCLUSIONS: These findings suggest a reduced role for nursing homes in caring for persons with severe mental illness, especially those who are young and do not have comorbid physical conditions. Overall, it appears that nursing homes play a relatively minor role in the present system of mental health services for all but elderly persons with dementia.

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Managed care holds the promise of facilitating parity between general medical care and alcohol, drug, and mental health care by reducing expenditures, even while expanding benefits. Limitations in our knowledge of variations in needs and treatment standards for substance use and psychiatric illnesses make such disorders an easy target for management. Costs for behavioral health care services have been reduced at a faster pace than has been the case for general medical care costs. The most severely ill face the potential burdens of managed care as access and intensity of care become more uniform across patient populations.

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We examined the adequacy of decorrelation of the responses to dichotic noise as an explanation for the binaural masking level difference (BMLD). The responses of 48 low-frequency neurons in the inferior colliculus of anesthetized guinea pigs were recorded to binaurally presented noise with various degrees of interaural correlation and to interaurally correlated noise in the presence of 500-Hz tones in either zero or pi interaural phase. In response to fully correlated noise, neurons' responses were modulated with interaural delay, showing quasiperiodic noise delay functions (NDFs) with a central peak and side peaks, separated by intervals roughly equivalent to the period of the neuron's best frequency. For noise with zero interaural correlation (independent noises presented to each ear), neurons were insensitive to the interaural delay. Their NDFs were unmodulated, with the majority showing a level of activity approximately equal to the mean of the peaks and troughs of the NDF obtained with fully correlated noise. Partial decorrelation of the noise resulted in NDFs that were, in general, intermediate between the fully correlated and fully decorrelated noise. Presenting 500-Hz tones simultaneously with fully correlated noise also had the effect of demodulating the NDFs. In the case of tones with zero interaural phase, this demodulation appeared to be a saturation process, raising the discharge at all noise delays to that at the largest peak in the NDF. In the majority of neurons, presenting the tones in pi phase had a similar effect on the NDFs to decorrelating the noise; the response was demodulated toward the mean of the peaks and troughs of the NDF. Thus the effect of added tones on the responses of delay-sensitive inferior colliculus neurons to noise could be accounted for by a desynchronizing effect. This result is entirely consistent with cross-correlation models of the BMLD. However, in some neurons, the effects of an added tone on the NDF appeared more extreme than the effect of decorrelating the noise, suggesting the possibility of additional inhibitory influences.

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