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We present photometric and spectroscopic data on three extragalactic luminous red novae (LRNe): AT 2018bwo, AT 2021afy, and AT 2021blu. AT 2018bwo was discovered in NGC 45 (at about 6.8 Mpc) a few weeks after the outburst onset. During the monitoring period, the transient reached a peak luminosity of 1040 erg s−1. AT 2021afy, hosted by UGC 10043 (∼49.2 Mpc), showed a double-peaked light curve, with the two peaks reaching a similar luminosity of 2.1(±0.6)×1041 erg s−1. Finally, for AT 2021blu in UGC 5829 (∼8.6 Mpc), the pre-outburst phase was well-monitored by several photometric surveys, and the object showed a slow luminosity rise before the outburst. The light curve of AT 2021blu was sampled with an unprecedented cadence until the object disappeared behind the Sun, and it was then recovered at late phases. The light curve of LRN AT 2021blu shows a double peak, with a prominent early maximum reaching a luminosity of 6.5 × 1040 erg s−1, which is half of that of AT 2021afy. The spectra of AT 2021afy and AT 2021blu display the expected evolution for LRNe: a blue continuum dominated by prominent Balmer lines in emission during the first peak, and a redder continuum consistent with that of a K-type star with narrow absorption metal lines during the second, broad maximum. The spectra of AT 2018bwo are markedly different, with a very red continuum dominated by broad molecular features in absorption. As these spectra closely resemble those of LRNe after the second peak, AT 2018bwo was probably discovered at the very late evolutionary stages. This would explain its fast evolution and the spectral properties compatible with that of an M-type star. From the analysis of deep frames of the LRN sites years before the outburst, and considerations of the light curves, the quiescent progenitor systems of the three LRNe were likely massive, with primaries ranging from about 13 M⊙ for AT 2018bwo, to 14−1+4 M⊙ for AT 2021blu, and over 40 M⊙ for AT 2021afy.

The NMDA subtype of glutamate receptor plays an important role in the molecular mechanisms of learning, memory and excitotoxicity. NMDA receptors are highly permeable to calcium, which can lead to the activation of the calcium-dependent protease, calpain. In the present study, the ability of calpain to modulate NMDA receptor function through direct proteolytic digestion of the individual NMDA receptor subunits was examined. HEK293t cells were cotransfected with the NR1a/2A, NR1a/2B or NR1a/2C receptor combinations. Cellular homogenates of these receptor combinations were prepared and digested by purified calpain I in vitro. All three NR2 subunits could be proteolyzed by calpain I while no actin or NR1a cleavage was observed. Based on immunoblot analysis, calpain cleavage of NR2A, NR2B and NR2C subunits was limited to their C-terminal region. In vitro calpain digestion of fusion protein constructs containing the C-terminal region of NR2A yielded two cleavage sites at amino acids 1279 and 1330. Although it has been suggested that calpain cleavage of the NMDA receptor may act as a negative feedback mechanism, the current findings demonstrated that calpain cleavage did not alter [(125)I]MK801 binding and that receptors truncated to the identified cleavage sites had peak intracellular calcium levels, (45)Ca uptake rates and basal electrophysiological properties similar to wild type.

To review reports of angiooedema and urticaria associated with angiotensin converting enzyme inhibitors (ACEI) in the New Zealand Centre for Adverse Reactions Monitoring and Intensive Medicines Monitoring Programme (IMMP) database.Adverse reaction reports describing angiooedema and/or urticaria between April 1981 and December 1994 were examined. Captopril, enalapril and lisinopril were intensively monitored on the IMMP during this period.Of a total of 116 reports there were 68 reports of angiooedema and 37 of urticaria alone and 11 where angiooedema and urticaria occurred in the same patient. The total number of patients is unknown, but cohorts of patients on captopril, enalapril and lisinopril in the IMMP were 16342, 25686 and 11235, totalling 53263 patients. There were 63 reports of angiooedema/urticaria in patients monitored on the IMMP, giving a reported rate of 1.2/1000 (0.9-1.5). Forty seven reactions occurred between 3 weeks and 4 years after commencement of therapy. Severe angiooedema occurred in 9 patients with early-onset angiooedema and 6 with late-onset angiooedema. There were no deaths. Seventeen patients had up to 12 episodes before diagnosis. Angiooedema/ urticaria occurred without gender preference. Although a dose relationship was not apparent, 3 patients developed angiooedema or urticaria after an increase in dose.Although reactions are more common shortly after initiation of ACEI therapy, late onset reactions may be less well recognised. Clinicians should be reminded, and ACEI data sheets should emphasise, that onset may be delayed for weeks or months, that patients may have multiple episodes with long symptom free intervals, and that angiooedema may occur with or without urticaria.

The 1992 American Association on Mental Retardation's (AAMR) definition and classification of mental retardation is different from the previous classification system in that: (a) a single diagnostic code of mental retardation is used if the person meets the three criteria of age of onset (18 or under), significantly subaverage abilities in intellectual functioning, and related limitations in two or more adaptive skills areas; (b) the person's strengths and weaknesses are described in reference to four dimensions: intellectual functioning and adaptive skills; psychological and emotional well-being; health, physical well-being, and etiology; and life activity environments; and (c) a profile of needed supports is developed across the four dimensions. In this article we discussed six major implications of the 1992 System for the field of mental retardation.

The field of mental retardation is being changed by a paradigm shift in how mental retardation is conceptualized and in how services are provided. This new way of thinking is reflected in the 1992 AAMR definition of what mental retardation is (Luckasson et al., 1992). Prevention efforts must also reflect this new way of thinking, which focuses on the interaction between individuals and their environment. In this paper, the stage was set for adoption of a new vision of prevention that incorporates an ecological approach to understanding the causation of mental retardation. The articles in this symposium were reviewed and their relevance to this new vision discussed. A comprehensive, coordinated, and integrated prevention program is needed that includes new strategies addressing a variety of personal, social, and environmental risk factors and on the interactions among them.

Both respirator support and medications used to facilitate extubation of premature babies potentially affect weight gain. We reviewed the charts of 100 pts whose birth weights were ≤1 kg and who had received full enteral feedings for at least 7 days before and after extubation. We determined the effects of ventilator support (SIMV, NCPAP) and medications (caffeine, theophylline, dexamethasone) on weight gain normalized for weight and caloric intake (gm/kg/Kcal/d) for the 7 days prior to and after extubation, excluding the day of extubation, a total of 1400 observations. (Table) Dexamethasone therapy dramatically reduced growth, a result previously reported. Methylxanthines had absolutely no effect on calorie utilization for growth. NCPAP caused a 20% reduction in growth, a result that was statistically insignificant. The known imprecision of daily weights in small babies may mask a clinically significant difference in growth of small babies on NCPAP. Despite the use of dexamethasone and NCPAP in the post-extubation period, extubation resulted in a small increase in weight gain. Prolonging mechanical ventilation in these tiny babies carries known risks and does not promote growth.

disease in an epidemiologic study. AmJ Cardiol 1970;25:325-8. 7 Kreger BE, Cupples LA, Kannel WB. The electrocardiogram in prediction of sudden death: Framingham study experience. Am Heart J 1987;113:377-82. 8 Rabkin SW, Mathewson FAL, T?te RB. The electrocardiogram in apparently healthy men and the risk of sudden death. Br Heart J 1982;47:546-52. 9 Kagan A, Yano K, Reed DM, MacLean CJ. Predictors of sudden cardiac death among Hawaiian-Japanese men. AmJ Epidemiol 1989;130:268-77. 10 Vandenbroucke JP, Matroos AW, Van der Heide-Wessel C, Van der Heide RM. Parental survival, an independent predictor of longevity in middle aged persons. Am J Epidemiol 1984;119:742-50. 11 Miettinen OS. Theoretical epidemiology. Principles of occurrence research in medicine. Chichester: Wiley, 1985. 12 Miettinen OS. Design options in epidemiologic research. An update. ScandJ Work Environ Health 1982; suppl 1:7-14. 13 Miettinen OS. The "case-control" study: valid selection of subjects. J Chrome Dis 1985;38:543-8. 14 van der Heide RF. Resultaten van een geneeskundig onderzoek van 3091 gezonde mannen en vrouwen, 40-65 jaar oud [PhD thesis]. Amsterdam: University of Amsterdam, 1959. 143 pp. 15 Manual of the international statistical classification of diseases, injuries, and causes of death. 9th ?d. Vol 1. Geneva: World Health Organisation, 1977. 16 Greenland S. Adjustment of risk ratios in case-base studies (hybrid epidemio logic designs). StaiMed 1986;5:579-84. 17 Fortuin NJ, Friesinger GC. Exercise-induced ST-segment elevation. Clinical, electrocardiographic and art?riographie studies in twelve patients. AmJMed 1979;49:459-64. 18 Bruce RA, Fisher LD, Pettinger M, Weiner DA, Chaitman BR. ST segment elevation with exercise: a marker for poor ventricular function and poor prognosis. Coronaryartery surgery study (CASS) confirmation of Seattle heart watch results. Circulation 1988;77:897-905. 19 Ellestad MH. Stress testing. Principles and practice. Philadelphia: F Davis, 1980:95-102. 20 Quyyumi AA, Wright C, Fox K. Ambulatory electrocardiographic ST segment changes in healthy volunteers. Br Heart J 1983;50:460-4. 21 Bruce RA, Irving JB. Exercise electrocardiography. In: Hurst W, ed. The heart, arteries and veins. 4th ed. New York: McGraw-Hill, 1978.

The influence of low‐power CO2 laser radiation upon the internal and translational energy of a supersonic SF6 molecular beam has been investigated. A line‐tunable cw (chopped) laser beam, approximately 7 W, is used to irradiate the gas in the expansion region at the exit of the nozzle. Time‐of‐flight analysis of the skimmed SF6 beam has been carried out using an electron bombardment ionizer–mass filter for monitoring number density. A pumped, liquid He‐cooled (1.8 K) bolometer was used to measure laser‐induced changes in total energy flux (power) of the incident beam. Vibration–translation/rotation relaxation converts some of the absorbed infrared (IR) energy into translational kinetic energy, as manifested by an increase in both transverse and axial velocity of the SF6 molecules. A significant loss of forward beam flux due to the enhanced radial velocity component is observed. From data on the number density of the SF6 beam, its velocity distribution and the power delivered to the bolometer, the laser‐in...

The purpose was to evaluate ways of predicting the onset frequency of the second vowel formant (F2) following consonant constrictions. Spectrograms of 604 constrictions were measured to obtain the frequency and slope of F2 offset just prior to each constriction, the duration of the constriction, and the frequency of F2 onset after the constriction. Three types of F2 onset prediction were applied to each constriction: (1) holding the F2 offset frequency, (2) linear extrapolation of F2 offset slope, and (3) exponential extrapolation of the offset slope. Statistical analyses of these data indicated that linear extrapolation gave poor results, that holding predictions were superior to predicting merely the modal onset, and that exponential extrapolations were better than holding offsets under certain conditions of offset slope and frequency region. Articulatory place and complexity of consonant constriction were found to be related to prediction error.

Thirty three reports of cough associated with captopril and 26 associated with enalapril received by the New Zealand intensive medicines monitoring programme were reviewed. The programme is a specialised part of the New Zealand postmarketing surveillance system. Review of these reports showed that the cough was an adverse reaction to the drugs, occurred even with low dose treatment, and was severe enough to warrant withdrawal of the drugs in most of the cases reported. A significant sex difference was shown, with women predominating. The reaction seemed to be a greater problem with enalapril, and in seven patients it occurred with both captopril and enalapril. Withdrawal of treatment resulted in rapid recovery, and no long term effects were shown. The pathogenesis of the reaction is unknown, but possible mediators include bradykinin and prostaglandins.

We tested the hypothesis that parents of children with epilepsy may have unmet information needs because their physicians do not fully appreciate what those needs are. Twenty-four parents ranked 60 items of possible concern to them that reflected medical, school, socialization, personality, and family relationship issues. Five neurologists who treat children with epilepsy ranked the same 60 items to predict parental concerns. Ranking was performed using the Q-sort technique. Parents' and physicians' rankings were compared using a two-tailed Mann-Whitney U test. There was a statistically significant difference between the two groups on 17 of the 60 items. The physicians tended to overestimate the importance of medical concerns and underestimate the importance of psychosocial concerns. Poor communication may occur when physicians do not recognize parental concerns or parental levels of understanding of health and illness.

A barbiturate (phenobarbital or primidone) was withdrawn over a period of 3 months from 25 institutionalized residents, all of whom had had three seizures or less in the past 6 months and were maintained on a nonsedating drug (phenytoin, carbamazepine, or valproic acid). Results were compared with a matched comparison group maintained on both drugs. Subjects withdrawn from primidone, but not those withdrawn from phenobarbital, had increased seizure frequency, probably due to withdrawal. After 14 months, seizure-free subjects withdrawn from barbiturates were no more likely to have had seizures than were comparison subjects. Barbiturates appear to be unnecessary and may be withdrawn.

Sidetone delay (delayed auditory feedback) is known to cause speakers to talk more slowly, and at delays of about 200 ms also causes severe articulation disturbances. If shorter delays can slow speech without adverse effects on articulation, this effect could be used to make talkers speak more slowly in certain communications situations. Subjects read lists of 1, 2, 3, or 4 syllable words and of sentences under each of 6 delay conditions (0, 7.5, 15, 30, 60, and 100 ms). Delays of 15–30 ms caused a significant slowdown in speaking rate with no adverse effects on articulation. Delays of 60–100 ms caused a greater slowdown but also had a noticeable adverse effect on speech quality, especially for sentences and polysyllablic lists. In communications situations where the quality of transmitted speech is degraded (e.g., vocoded speech), sidetone delay may be useful in modifying the talk's behavior to improve overall speech quality.

Method and results are presented for the application of statistical pattern‐recognition techniques to automatic classification of words and talkers using formant‐tracking data as the input. The method employs the expression of an entire formant pattern as a single n‐dimensional vector. Each vector component represents a sample of one of the formant functions at a giventime. Thus, the dimensionality of the n space is determined by the product of the number of formant parameters sampled and the number of observation epochs. A computer program processes these data in two steps. In the first step, called a “learning” program, separate statistical categories are established by the computation of the mean vector and covariance matrix describing a normal distribution function for the set of vectors that define each category. In the second step, called the “recognition” program, an unknown is recognized by computing the statistical distance to all possible categories and selecting the category for which this distance is minimum. Results, in the form of confusion matrices, are presented for word recognition of the first ten letters of the alphabet as spoken by 10 talkers and for recognition of the talkers.

In a formant‐tracking vocoder, any lag in acquiring correct formant‐frequency values, after the release of a consonant, produces false formant transitions; these may cause an error in transmission of the consonant. Tracking of the second formant (F2) is especially critical in this respect. In the present study, some means of predicting F2 are presented. F2 relations across consonant constrictions were measured in spectrograms of the spontaneous speech of five male speakers. The study compared prediction of the frequency of postconsonantal F2 by three extrapolations of preconsonantal F2: (1) holding the last value; (2) linear extrapolation of the last course; and (3) exponential extrapolation of the last course. Holding and exponential extrapolation were superior to linear extrapolation. Mean prediction error was about 300 cps with the two better methods. Errors were then partitioned according to upward or downward last course, in conjunction with high‐middle, or low‐frequency regions for the beginning of extrapolation. Certain partitionings reduced mean prediction error to 200 cps. [Research supported in part by the U. S. Army Electronics Research and Development Laboratory.]

Work with a voice‐excited formant vocoder has led to experiments on several other methods of processing speech. These methods make use of the baseband and some of the same types of information which are normally derived by a formant vocoder, such as front‐back vowel detection and voice‐voiceless discrimination, but applied in a manner different from a normal formant vocoder. The systems so far tested are characterized by transmission of the baseband in unprocessed form and the regeneration of higher frequency information by deriving it from the baseband or simple parameters. While these systems do not yield high quality speech, the intelligibility may be high enough for certain limited applications. Tape recordings of these systems will be presented.

A formant‐tracking method based on the measure of majority period is discussed. This tracker employs as input data the instantaneous period measures of formants that have been selected by appropriate formant‐range filters. These periods are subjected to an electronic circuit that, by a unique feedback arrangement, suppresses periods that deviate beyond a fixed threshold distance from the mean period. The resulting circuit output very nearly tracks the majority period of the set of periods that originally comprised the input data. The method also incorporates a means of weighting the majority period formant measure toward the median of the formant range. By this means, the tendency to be captured by adjacent formants is significantly reduced. The paper describes the method of implementation and the application of the method to formant tracking in the second‐formant range. [Research supported in part by U. S. Army Electronics Research and Development Laboratory.]

The formant vocoder has now been under investigation for use as a speech‐compression system for more than a decade. During that time, significant advances have been made in the technology of the analysis and synthesis portions of the formant vocoder, and in the encoding of the parametric control signals for communication of the speech information at data rates normally of 1200 bit/sec and as low as 600 bit/sec. The consequence has been considerably improved vocal quality and articulation. Also, a voice‐excited operation mode has been developed for the formant vocoder that is designed to provide high‐quality speech transmission at a data rate of 4800 bit/sec. In this paper, some of the more important aspects of the formant‐vocoder system design are to be discussed. These include adaptive techniques for formant‐frequency tracking the use of the serial vocal analog for synthesis, encoding techniques for transmission of the vocoder parameters in binary form, and the voice‐excited mode of operation of the form...

This paper discusses design and performance of a speech‐compression system that incorporates a formant‐tracking vocoder for the analysis‐synthesis of the vocalic utterances in speech, and a channel vocoder with 5 fixed‐frequency channels and 1 tracking channel for the analysis‐synthesis of the nonvocalic utterances of speech. The information is multiplexed and transmitted over eight 25‐cps low‐pass analog channels. For vocalic utterances, the parameters transmitted are the first 3 formants, their respective amplitudes, the frequency of pitch, and a separate vocalic nonvocalic decision signal. For nonvocalic utterances, the information transmitted is the amplitude of 5 vocoder channels. and the frequency and amplitude of 1 tracking channel covering the range from 2300 to 6000 cps, used to control a variable‐frequency pole‐zero filter in the synthesizer. For male talkers, this system demonstrates a mean articulation score of 87%. Confusion matrices and a demonstration tape recording are presented.

One of the formant vocoder's principal promises lies in the more efficient encoding of the word information content of speech than can be achieved by the use of the more familiar channel vocoder. The consequence of this more efficient encoding manifests itself in the capability for encoding speech for binary‐encoded formant data at binary‐data rates potentially as low as 150 bits/sec. In this paper, various avenues of approach for achieving such low‐binary‐data‐rate transmission are explored for system operation at various data rates ranging from 150 to 1200 bits/sec. Results of recent laboratory tests are presented.