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Multiple-target tracking algorithms generally operate in the local frame of the sensor and have difficulty with track reallocation when targets move in and out of the sensor field-of-view. This poses a problem when an unmanned aerial vehicle (UAV) is tracking multiple ground targets on a road network larger than its field-of-view. To address this problem, we propose a Rao-Blackwellized Particle Filter (RBPF) to maintain individual target tracks and to perform probabilistic data association when the targets are constrained to a road network. This is particularly useful when a target leaves and then re-enters the UAV's field-of-view. The RBPF is structured as a particle filter of particle filters. The top level filter handles data association and each of its particles maintains a bank of particle filters to handle target tracking. The tracking particle filters incorporate both positive and negative information when a measurement is received. We implement two path planning controllers, receding horizon and deep reinforcement learning, and compare their ability to improve the certainty for multiple target location estimates. The controllers prioritize paths that reduce each target's entropy. In addition, we develop an algorithm that computes the upper bound on the filter's performance, thus facilitating an estimate of the number of UAVs needed to achieve a desired performance threshold., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Moore, Bidstrup, Peterson and Beard.)

Follicular fluid steroid content and theca and granulosa cell steroidogenesis in pelvic congestion cystic ovaries were compared with steroidogenic function in both normal and polycystic ovaries. Ovaries were obtained at oophorectomy for benign gynaecological conditions, and classified according to gross morphology at dissection. Individual follicles were dissected out, follicular fluid aspirated, and granulosa and theca cells cultured in vitro. Androstenedione, progesterone and oestradiol content of the follicular fluid and overlying culture medium were measured by radioimmunoassay. There was a significant elevation of both basal and LH-stimulated androstenedione production by theca from both polycystic ovaries (n = 10; P < 0.005) and pelvic congestion cystic ovaries (n = 8; P < 0.05 and < 0.01 respectively) as compared with normal ovaries (n = 5). Granulosa cells from pelvic congestion ovaries (n = 7) had a diminished oestradiol response to FSH as compared with those from normal ovaries (n = 8). Follicular fluid from the majority of follicles in the pelvic congestion cystic ovaries had a high androgen:oestrogen ratio consistent with atresia. For the first time, pelvic congestion ovaries characterized by predominantly atretic follicles scattered throughout the stroma in a normal volume ovary are reported. Follicular atresia was reflected by reduced granulosa cell responsiveness to FSH, theca cell hyperplasia and increased basal and LH-stimulated androgen production. These ovaries are functionally distinct from polycystic ovaries, which do not have a higher proportion of atretic follicles than normal ovaries.

The diagnosis and management of lower abdominal pain is difficult, particularly for the inexperienced accident and emergency (A&E) or surgical trainee. In women, potential gynaecological causes may further confuse the picture. We analysed the incidence, spectrum of presentation and immediate management of 322 women presenting consecutively to an inner city A&E department over a 6-month period with lower abdominal pain. A standard questionnaire relating to history, examination, immediate investigations and preliminary diagnosis was completed by the attending A&E doctor. The cause of abdominal pain, according to the A&E doctor's diagnosis, was gynaecological in 61%, gastroenterological in 23%, urological in 7% and non-specific in 9% of cases. Of the women, 39% (124/322) were referred to a duty specialist, of whom 86% (107/124) required admission for investigation and/or treatment. Women initially diagnosed as having pain of gynaecological origin formed the largest group of patients to be referred. In 69% (67/97) of these cases, the A&E doctor's initial diagnosis was confirmed by the gynaecologist. This study shows that pain of gynaecological origin was the largest single cause of lower abdominal pain in women presenting to our A&E department and that, in the majority of cases, these women needed to be referred to the duty gynaecologist for immediate treatment. Although overall diagnostic accuracy rate was relatively high, the management of potentially life-threatening gynaecological conditions such as ectopic pregnancy was poor. These results emphasise the need to improve in-service gynaecological training in A&E departments.

The human ovarian vein is of particular interest as an adult vessel which changes with the different phases of reproductive life. At the ultrastructural level we have characterised the endothelium, vascular smooth muscle and autonomic innervation of the human ovarian vein. Transmission electron micrographs were prepared from surgical specimens of the human ovarian vein (n = 11) to demonstrate the features of the vessel wall. The pattern of innervation was investigated using an image analysis system which was also used with high-magnification micrographs to count and measure axonal vesicle types. Possible relationships between ultrastructural features and age and reproductive history were investigated. Endothelial cells contained Weibel-Palade bodies and numerous microfilaments. There were 3 muscle coats: no elastic lamina separated the endothelium from an inner layer of smooth muscle; a middle smooth muscle layer consisted of cells orientated in a circular fashion; an outer smooth muscle layer was made up of longitudinally arranged smooth muscle bundles with collagen and nerves penetrating throughout. The percentage of the vessel thickness occupied by the middle circular smooth muscle layer ranged from 0 to 33% and fell with increasing age (r = -0.67, P < 0.05). Penetration of nerves into the circular layer was observed only in 2 of 9 specimens. The observed ultrastructural features are consistent with the ability of the ovarian vein to distend substantially in response to changing circulatory demands. The vascular endothelium may have a role in the local control of haemostasis via the synthesis and storage of von Willebrand factor.(ABSTRACT TRUNCATED AT 250 WORDS)

Study Objective: To investigate the consequences of different levels of caesarean section (CS) rate in terms of fetal and maternal outcomes., Design: Comparison of outcome variables between four categories of maternity units stratified according to CS rates. Data were collected concurrently., Settings: All 17 maternity units in one health region., Subjects: Data for the perinatal mortality analysis: all 221,867 deliveries in 1983-87 (excluding severe malformations) (1462 deaths); maternity information analysis system: all 36,727 women with singleton pregnancies who delivered in 1988., Outcome Measures: Perinatal mortality, Apgar scores at one and five minutes, onset of respiration after one minute, postnatal transfusion, postnatal infection, thromboembolism, low haemoglobin concentration at discharge, and puerperal psychosis were determined., Results: Teaching hospitals with an increased proportion of high risk cases had the highest CS rate, but the other three categories were found to serve comparable populations. Perinatal mortality showed a birthweight specific pattern--for very low birthweight infants, but not for other deliveries, mortality rates were lower in units with higher CS rates. Apgar scores showed no trend, but the onset of respiration after one minute was significantly more frequent in units with a CS rate of less than 10%. Increased maternal postnatal blood transfusion was associated with higher CS rates but no trend was observed for the other maternal variables., Conclusions: CS rates in general maternity units should be 10 to 12% or lower in the singleton population as a whole, but a more interventionist approach is indicated for very low birthweight infants. If confirmed, these recommendations could easily be incorporated into clinical audit.

Patients with chronic pelvic pain attending a tertiary referral centre show certain social, developmental and psychological characteristics. Specifically, they appear to have fewer children and to report more paternal overprotection, and a trend towards low maternal care compared to normals. They also show more depression, free-floating anxiety and somatic anxiety than such populations. The levels are similar to those found in other outpatient populations presenting with migraine or irritable bowel syndrome. Hostility levels are greater than those in normal subjects. Overall the present patient population reports the same degree of childhood sexual abuse as do many other female clinic and community sample populations. Sexual abuse is unlikely to be a specific aetiological factor in the development of chronic pelvic pain though it may yet be found to be important in subsets of the population.

Computer generated and dictated discharge summaries were compared for all 133 babies admitted for intensive and special care during a six month period. Whereas 130/133 (98%) had a computer generated summary, only 94/133 (71%) had a dictated summary. In addition, computerised summaries were completed at discharge, but there was a delay up to 26 weeks for dictated summaries. Dictated summaries had more items of basic data missing but were more readable. A main diagnosis was missing in only 5/95 (5%) of dictated and 1/130 (1%) computerised summaries. Of the computer generated summaries, 114/133 (86%) were suitable to give to parents. Satisfactory discharge summaries for babies requiring intensive or special care can be generated with an on line computer system.

The value of the Isaacs endometrial cell sampler in the cytologic assessment of the endometrium was studied in 121 unanaesthetised patients aged over 40. Satisfactory aspirates for cytological diagnosis of endometrial state were obtained in 111 patients (91%) whereas endometrial specimens for histological diagnosis were obtained in only 89 patients (79%). In only four out of 83 cases were there diagnostic discrepancies between the aspirates and the curettings. It is concluded that the technique is safe, quick, comfortable, and reliable for assessing endometrial state. It should therefore prove valuable for screening, particularly in the management of menopausal women requiring oestrogen treatment.

Endometrial aspiration cytology has been shown by multicentre prospective studies to be an acceptable and valuable method of assessing the endometrium. A retrospective study was undertaken over three years' routine use of the Isaacs cell sampler. In 86% of the cases suitable endometrium was obtained, with experience of the technique being the important factor. When compared with histological findings, all 11 cases of malignancy were confirmed, including one ovarian adenocarcinoma. Of the cytological reports of endometrial hyperplasia, 78% were confirmed by the histological findings, with the remainder showing minor degrees of cystic hyperplasia or normal endometrium. In no case was a more abnormal lesion present on histological examination than had been suggested by cytological findings. The use of progestogens in reversing hyperplasia is seen to be effective, though the long term benefit remains uncertain. It is concluded that with an experienced cytologist, Isaacs endometrial aspiration should be used routinely for the primary investigation of dysfunctional uterine bleeding and postmenopausal bleeding.

An attempt has been made to monitor by continuous fetal heart rate according all women admitted in labour. Altogether 85% of the 1070 patients delivered at one hospital were monitored in 1973 and 92% in 1974. Perinatal mortality fell significantly from levels in preceding years to 15-8 and 11-7 per 1000 births, respectively, in 1973 and 1974. The fall was primarily due to the elimination of intra-partum stillbirths and a significant reduction in neonatal mortality. The incidence of caesarean sections also fell from 9-7% in 1973 to 5-8% in 1974. All patients should be monitored because it is impossible to predict reliably intra-partum fetal distress from maternal "high-risk" factors present before the onset of labour.

Very early termination of pregnancy was performed on 424 women in three London teaching hospitals. Altogether 90% of the women were no more than 14 days overdue, and 67% of these had histological evidence of pregnancy. The procedure differed little in technique or its acceptability to the patient from termination done later in the first trimester. The similar incidence of complications suggested that it is not an alternative to conventional contraception. The response of patients, general practitioners, and referral agencies, however, indicated that there is a definite need in the community for a very early termination service.

Diurnal plasma glucose profiles and oral glucose tolerance during pregnancy were studied in normal women, chemical diabetics, and insulin-requiring diabetics. In normal women the mean diurnal plasma glucose rose by only 0.22 mmol/1 (4 mg/100 m1) during pregnancy. Mild chemical diabetes resulted in an increase in both the mean diurnal glucose concentration and the fluctuation of plasma glucose levels during the day. Fluctuation in glucose concentration in insulin-dependent diabetics was about three times that found in non-diabetic women of similar gestation, with relative hyperglycaemia during the day and hypoglycaemia at night. In non-diabetic women and those with chemical diabetes the mean dirunal glucose correlated closely with the total area under the three-hour oral glucose tolerance curve and significantly, but less closely, with the two-hour glucose tolerance test value.

Fetal heart rate (FHR) was recorded and maternal blood pressure measured in 104 patients in whom lumbar epidural analgesia was induced in labour. Fifty-one patients received an intravenous load of 11 of Hartmann's solution immediately before the epidural injection. This infusion significantly reduced the incidence of abnormalities of FHR from 34% to 12% and of maternal hypotension from 28% to 2%. We did not study mothers with pre-eclampsia and hypertension, but we conclude that there is a strong case for preloading all other mothers in whom lumbar epidural analgesia is induced in labour.

A selection of psychological and social factors present in 360 women who underwent legal termination of pregnancy are related to their contraceptive practice. One-third of the group were ignorant about contraceptive methods, ignorance being more common in women from social classes IV and V and in those under the age of 19. Nearly half of those who had some knowledge of contraceptive practice became pregnant after knowingly taking a risk. A total of 41% had been using some form of contraception immediately before conception. The reliability of contraceptive methods used was found to be inversely related to neuroticism scores obtained from the Eysenck Personality Inventory, neuroticism being highest in women who had not used any form of contraception.Of 91% of the group seen three months after their termination 86% were using reliable contraceptive methods. A follow-up study one or two years after termination has shown that 81% of the 215 women contacted so far are using a reliable method of contraception; two unwanted pregnancies have occurred but both were due to contraceptive failure. This satisfactory outcome has been ascribed to the system of counselling all women before and after termination.

Diurnal plasma free fatty acid (FFA) and glucose concentrations were measured in 23 normal women, 13 chemical diabetics, and 11 insulin-dependent diabetics in late pregnancy. The mean diurnal FFA value was lowest in the insulin-requiring diabetics and highest in the chemical diabetics. Although no association was found between percentile birthweight and maternal mean fasting or diurnal FFA, there was a positive correlation between percentile birthweight and both mean maternal fasting plasma glucose and mean diurnal glucose in normal and chemical diabetic women. These observations support the view that glucose is the major substrate used by the fetus, but birthweight may be influenced more by the total substrate crossing the placenta than by maternal levels of either glucose or FFA alone.

Successful therapeutic abortion was performed consecutively by an intra-amniotic injection of hypertonic saline in 102 out of 110 patients in whom the size of the uterus corresponded with a pregnancy of 16 weeks or more.A spontaneous abortion of the fetus followed the injection alone in 92 of the cases, and the overall injection-delivery interval was 39.75 (range 11-98) hours. In 10 women intravenous oxytocin injection was used as an additional uterine stimulant because contractions were not established after 48 hours. Complete spontaneous expulsion of the placenta occurred in 71 cases, and evacuation of the placenta under general anaesthesia was required in the other 31.No major complication occurred among the 110 patients.

The effects of a maternal intravenous glucose load on the fetal plasma levels of glucose and insulin have been studied in 11 patients before the onset of labour. Within five minutes the fetal plasma glucose concentration rose significantly, indicating a rapid transfer of glucose across the placenta. Following this, the rate of fall in fetal plasma glucose closely reflected that in the mother.Serial fetal insulin estimations carried out in 8 of the 11 subjects following maternal glucose showed an early rise in fetal insulin in four and a delayed rise in one; in the remaining three there was no definite change.It is concluded that the blood glucose level of the fetus is controlled by that of the mother, but that the fetal pancreas at term may respond to hyperglycaemia by the secretion of insulin.

The practical application of foetal blood sampling in the routine management of patients in labour has been reviewed in a six-month survey, during which time 1,668 patients were delivered at Queen Charlotte's Hospital.Foetal acidaemia (pH 7.25 or less) occurred in 45 of the 295 patients who showed clinical signs of foetal distress. Foetal tachycardia was the presenting sign in 33 of these 45 patients, underlining the importance of this physical sign. Foetal acidaemia in association with clinical foetal distress occurred twice as often in patients who had complications of pregnancy and who were therefore regarded as obstetrically "at risk" as it did in patients who were obstetrically "normal" No cases of acidaemia were detected in any of the foetal blood samples performed routinely on "at-risk" patients in the absence of clinical foetal distress.

Termination of pregnancies ranging from 6 to 10 weeks' gestation is described in 127 women who attended the hospital as outpatients. The technique employed was to aspirate the products of conception through a narrow plastic tube using a high negative pressure. Infiltration of the cervix with local anaesthetic proved so effective that the procedure could be carried out on the fully conscious patient. The short time taken to evacuate the uterus, the small blood loss, and the low incidence of complications in the latter part of the study suggest that the technique is a valuable procedure. Relatively more women can be terminated as outpatients than as inpatients with a corresponding reduction in the demands made on gynaecological beds.

The effect of prolonged maternal hyperglycaemia on fetal plasma glucose and insulin concentrations was investigated in eight normal and nine diabetic patients. It was found that under fasting conditions the fetal glucose concentration in gestational diabetic pregnancies tended to be lower than in normal pregnancies. Insulin measurements suggested that this may be due to fetal hyperinsulinism in the diabetic group. During glucose infusion, regardless of the degree of maternal hyperglycaemia, the fetal glucose concentration was limited in 12 out of 13 cases to less than 200 mg/100 ml, with only small differences between normal and diabetic pregnancies. It is proposed that the placenta prevents unlimited transport of glucose to the fetus; yet in diabetic pregnancies a sequence of increased maternal-fetal glucose transport, fetal hyperinsulinism, and fetal hypoglycaemia may contribute to the observed perinatal mortality.

This report describes two cases of twin pregnancy in which continuous heart rate monitoring of both twins was successfully carried out during labour. In both cases monitoring permitted early diagnosis of fetal distress and both mothers were delivered by caesarean section. Continuous fetal heart rate monitoring permits diagnosis of fetal distress in the second twin much earlier than conventional methods.