Trends in the Management of Miscarriages with the Implementation of the Volunteer Obstetrician Scheme in Selected Primary Health Care Centres in Maiduguri, Northeastern Nigeria.

BACKGROUND: Post-abortion care (PAC) is a crucial component of emergency obstetric care, and many of the primary health care centres (PHC) in the internally displaced person (IDP) camps and host communities in Maiduguri lack it. Improved access to high-quality PACs is essential for meeting the reproductive health needs of the IDPs and reducing the maternal morbidity and mortality that can result from miscarriages. OBJECTIVE: To determine the trend in managing miscarriages in the IDP camps and host communities in Maiduguri and the impact of the volunteer obstetrician scheme (VOS) on PAC. METHODOLOGY: We conducted a longitudinal study in selected PHCs serving IDP camps and host communities in Maiduguri. The study spanned five (5) years, and we compared the management of miscarriages and PAC services one year before the VOS project, two years during the project and two years after the project. During the two-year VOS project, staff manning the PHCs had supportive supervision with hands-on training on PAC. Chi-square for trend and odd ratio with a 95% confidence interval was used as appropriate to compare the trend in PAC services provided during the study period. RESULTS: One thousand eight hundred and eight (1808) women presented with miscarriages, and 1562 (86.4%) required uterine evacuation. Medical evacuation with oral misoprostol was offered to 974 (62.4%), and manual vacuum aspiration (MVA) was used in 422 (27.0%) of the women who needed uterine evacuation. There was a statistically significant rise in the use of medical evacuation throughout the study period (52.2% before VOS, and 71.4% by the second year of VOS) with ꭓ2=41.64 and P<0.001. In comparison, the use of MVA fell from 38.6% in 2015 to 27.7% in 2019 (ꭓ2=34.74 and P<0.001). Similar rising trends were also observed in postabortion family planning acceptance (ꭓ2=22.27, P<0.001). CONCLUSION: The Volunteer Obstetrician Scheme project appears to have improved PAC services, especially medical evacuation and family planning uptake in the PHCs in IDP camps and host communities in Maiduguri, Borno State, Nigeria. We recommend task shifting of PAC services and periodic supportive supervision to ensure the quality of care.

CONTEXTE: Les soins après avortement (PAC) sont une composante cruciale des soins obstétricaux d'urgence, et de nombreux centres de soins de santé primaires (PHC) dans les camps de personnes déplacées internes (PDI) et les communautés d'accueil à Maiduguri en sont dépourvus. Un accès amélioré à des PAC de haute qualité est essentiel pour répondre aux besoins de santé reproductive des PDI et réduire la morbidité et la mortalité maternelles qui peuvent résulter des fausses couches. OBJECTIF: Déterminer la tendance dans la gestion des fausses couches dans les camps de PDI et les communautés d'accueil à Maiduguri et l'impact du Programme de bénévoles obstétriciens (VOS) sur la PAC. MÉTHODOLOGIE: Nous avons mené une étude longitudinale dans des PHC sélectionnés desservant des camps de PDI et des communautés d'accueil à Maiduguri. L'étude a duré cinq (5) ans, et nous avons comparé la gestion des fausses couches et les services de PAC un an avant le projet VOS, deux ans pendant le projet et deux ans après le projet. Pendant les deux ans du projet VOS, le personnel des PHC a bénéficié d'une supervision avec formation pratique sur la PAC. Le chi carré pour la tendance et le rapport de cotes avec un intervalle de confiance de 95% ont été utilisés, le cas échéant, pour comparer la tendance des services de PAC fournis pendant la période de l'étude. RÉSULTATS: Mille huit cent huit (1808) femmes ont présenté des fausses couches, et 1562 (86,4%) ont nécessité une évacuation utérine. Une évacuation médicale avec du misoprostol oral a été proposée à 974 (62,4%), et l'aspiration manuelle sous vide (AMV) a été utilisée chez 422 (27,0%) des femmes ayant besoin d'une évacuation utérine. On a observé une augmentation statistiquement significative de l'utilisation de l'évacuation médicale tout au long de la période de l'étude (52,2% avant le VOS et 71,4% la deuxième année du VOS) avec ꭓ2=41,64 et P<0,001. En revanche, l'utilisation de l'AMV est passée de 38,6% en 2015 à 27,7% en 2019 (ꭓ2=34,74 et P<0,001). Des tendances similaires à la hausse ont également été observées dans l'acceptation de la planification familiale après avortement (ꭓ2=22,27, P<0,001). CONCLUSION: Le projet de Programme de bénévoles obstétriciens semble avoir amélioré les services de PAC, en particulier l'évacuation médicale et l'acceptation de la planification familiale dans les PHC des camps de PDI et des communautés d'accueil à Maiduguri, dans l'État de Borno, au Nigéria. Nous recommandons de déléguer les services de PAC et une supervision de soutien périodique pour garantir la qualité des soins. MOTS-CLÉS: Communauté d'accueil, Camps de PDI, Aspiration manuelle sous vide, Évacuation médicale, Misoprostol, Soins après avortement.

Effect of Frequency of Antenatal Care Contacts on Maternal and Fetal Outcome in Low-Risk Pregnancies at Federal Teaching Hospital Gombe, Nigeria.

BACKGROUND: The frequency of antenatal care (ANC) contacts for low-risk pregnancies has been a subject of debate. OBJECTIVE: To determine the effect of frequency of ANC contacts on pregnancy outcomes amongst low-risk pregnancies and the reasons for the low antenatal visits at the Federal Teaching Hospital, Gombe, Nigeria. METHODOLOGY: This was a cross-sectional study of 510 low-risk pregnant women. They were divided into two groups; group I consisted of 255 women that had eight or more ANC contacts with at least five contacts in 3rd trimester, and group II consisted of 255 women that had seven or fewer ANC visits. Socio-demographic characteristics, haemoglobin levels at delivery, mode of delivery, maternal satisfaction, and birth outcomes were compared between the two groups. Reasons for the low antenatal visits were also documented. RESULTS: The prevalence of anemia was higher in group II compared to group I {29.4% versus 18.8% with OR 1.80 (95% CI 1.19-2.72)} while caesarean section rate was higher in group I compared to group II {16.9% versus 9.4% with OR=1.96 (95% CI: 1.11-3.48)}. There was no statistically significant difference in the fetal outcome between the two groups. Women with eight or more ANC contact were more satisfied with the ANC than those with fewer visits (OR=2.20, 95%CI 1.52-6.24). Late booking and facility-based lapses were mainly responsible for the fewer contacts. CONCLUSION: Having eight or more ANC contacts is associated with decreased maternal anaemia, better maternal satisfaction, and increased risk of caesarean delivery compared to women that have fewer ANC contacts.

CONTEXTE: La fréquence des contacts de soins prénatals (CPN) pour les grossesses à faible risque a fait l'objet d'un débat. OBJECTIF: Déterminer l'effet de la fréquence des contacts de soins prénatals sur les résultats de la grossesse parmi les grossesses à faible risque et les raisons pour lesquelles les visites prénatales sont peu nombreuses au Federal Teaching Hospital, Gombe, Nigéria. MÉTHODOLOGIE: Il s'agit d'une étude transversale portant sur 510 femmes enceintes à faible risque. Elles ont été divisées en deux groupes : le groupe I comprenait 255 femmes ayant eu huit contacts ANC ou plus, dont au moins cinq au cours du troisième trimestre, et le groupe II comprenait 255 femmes ayant eu sept visites ANC ou moins. Les caractéristiques sociodémographiques, les taux d'hémoglobine à l'accouchement, le mode d'accouchement, la satisfaction maternelle et les résultats de l'accouchement ont été comparés entre les deux groupes. Les raisons des faibles visites prénatales ont également été documentées. RÉSULTATS: La prévalence de l'anémie était plus élevée dans le groupe II que dans le groupe I {29,4 % contre 18,8 % avec un OR de 1,80 (IC à 95 % : 1,19-2,72)}, tandis que le taux de césarienne était plus élevé dans le groupe I que dans le groupe II {16,9 % contre 9,4 % avec un OR de 1,96 (IC à 95 % : 1,11-3,48)}. Il n'y a pas eu de différence statistiquement significative entre les deux groupes en ce qui concerne l'issue fœtale. Les femmes ayant eu huit contacts ou plus avec la CPN étaient plus satisfaites de la CPN que celles ayant eu moins de visites (OR=2,20, 95%CI 1,52-6,24). La prise de rendezvous tardive et les défaillances au niveau de l'établissement étaient principalement responsables du nombre inférieur de contacts. CONCLUSION: Le fait d'avoir huit contacts CPN ou plus est associé à une diminution de l'anémie maternelle, à une meilleure satisfaction maternelle et à un risque accru d'accouchement par césarienne par rapport aux femmes qui ont moins de contacts CPN. Mots-clés: Anémie, Anténatal, Résultat de l'accouchement, Contacts, Effet, Fréquence, Satisfaction maternelle.

Prevalence and risk factors of hypocalcemia among pregnant and non-pregnant women in Maiduguri, Nigeria: A cross-sectional study.

BACKGROUND: Pregnancy is a period of heightened calcium demand necessary for the optimum growth and development of the fetus and placenta. Women with low calcium intake may manifest with hypocalcemia in pregnancy. OBJECTIVE: The aim of this study was to determine the prevalence and risk factors of hypocalcemia among pregnant and non-pregnant women in Maiduguri, Nigeria. SUBJECTS AND METHODS: A comparative cross-sectional study was conducted at the University of Maiduguri Teaching Hospital, Maiduguri from 1st January 2017 to 31st December 2018. For each patient, sociodemographic and clinical characteristics were noted. Serum calcium, phosphate, total protein, and albumin were determined using spectrophometric methods with their specific reagents. The data obtained was analyzed using the SPSS statistical software for windows version 20. Chi-square test, Student t-test and ANOVA were used as appropriate. Odd ratio with multiple logistic regression was used to determine risk factors for hypocalcemia. P value < 0.05 was considered statistically significant. RESULTS: A total of 1,500 (1,000 pregnant and 500 non-pregnant) women were analyzed. The mean age, total protein, and albumin were similar in the pregnant and non-pregnant women. However, the non-pregnant women were of higher parity than the pregnant women (3.75 ± 2.79 versus 2.45 ± 2.24, P < 0.001). The staple food of both group were mainly high carbohydrate diets. The prevalence of hypocalcemia was 29.20% among the pregnant women and 14.20% among the non-pregnant women (X2 = 64.34, P < 0.001). The mean serum calcium was lower among the pregnant compared to the non-pregnant women (2.08 ± 0.22 mmol/L versus 2.2 ± 0.19 mmol/L, F = 5.73, P = 0.02). There were no statistically significant differences in the mean serum calcium across the trimesters of pregnancy (F = 1.58, P = 0.21). CONCLUSION: Hypocalcemia in pregnancy is common in our environment and it is associated with anemia in pregnancy, anorexia, and primigravidity while attainment of at least basic education is protective. We recommend routine calcium supplementation in pregnancy and preconception period.

Role of national blood transfusion service (NBTS) in promoting emergency obstetrics care (EMOC)

Background: Obstetrics haemorrhage is one of the leading cause of maternal mortality in our settings, this was compounded by the non availability to safe blood in situation of need. Hence the prompt access and availability of blood can avert this preventable cause of maternal death. Objectives: to highlight the benefits of effective collaboration with NBTS in ensuring prompt availability of blood for emergency obstetric services requiring blood for transfusion. Material And Method: All obstetrics cases requiring blood transfusion in FMC Nguru from 1st stJanuary 2006 ­ 31 December 2011 were retrospectively reviewed. Trends and pattern of the st strequest and source of blood were looked at within the two periods (from 1 January 2006 ­ 31 st stDecember 2008 and 1 January 2009 ­ 31 December 2011). Records of 1634 obstetric patients requiring blood transfusion or received blood transfusion in the maternity units were retrieved from the medical records, maternity ward record and blood bank. Information pertaining to their age, parity, indication for the transfusion or requests and source of blood was obtained for analysis. Data was analysed using simple percentage. st st Results: Between 1 January 2006 and 31 December 2008 only 513 (56%) of the units requested st st907 units of blood were supplied, while between 1 January 2009 and 1 December 2011 1367 ( 87%) of the 1567 units of blood requested were supplied. Within the earlier study period the only available source were from willing relatives and commercial blood donors, however between 2009 and 2011 more than 2/3 (64.2%) were supplied from the north east zonal NBTS office in Maiduguri. In 2006 through 2008, donation from relatives and commercial donors accounted for 53.22% and 46.78% respectively, but in 2009 and 2011 donation from relatives and commercial donors were recorded as 23.9% and 11.6% respectively. The commonest indication for the requests were anaemia, obstetrics haemorrhage (PPH, APH) and emergency C/S. Conclusion: Ready available source of blood will significantly improve timely availability of blood in our setting. There is the need to encourage this collaboration in other regions to ensure prompt availability of blood to attend to emergencies requiring blood transfusion

Indications and outcome of abdominal myomectomy in University of Maiduguri Teaching Hospital: Review of ten year.

BACKGROUND: Abdominal myomectomy is a common modality of treatment for large and symptomatic uterine fibroid in women who wish to retain their fertility. Though frequently performed the procedure may still be associated with complications. MATERIALS AND METHODS: A retrospective review of all patients who had abdominal myomectomy from January 1999 to December 2008 at the University of Maiduguri Teaching Hospital. Information on the Sociodemographic characteristics, indication for the myomectomy, uterine size, pre and post operative packed cell volume (PCV), intraoperative findings, cadre of surgeon, duration of hospital stay and complications were obtained. RESULTS: The rate of abdominal myomectomy was 3.34%. Majority of the patients (79.8%) aged 30-49 years, and most (58.9%) were nulliparas. Abdominal mass (63.7%), menorrhagia (57.7%), and subfertility 55.2% were the leading indications for abdominal myomectomy. Complications were seen in 10.9% of the cases, 55.5 % of which were wound infections. Clinical and intra operative factors associated with complications included menorrhagia (P=0.003), estimated blood loss (EBL) ≥500mls (P=0.005) and post operative PCV of <30% (P=0.081). CONCLUSION: Complication rate after myomectomy was low with menorrhagia and EBL ≥ 500 mls being significantly associated with development of complication.

Informed consent practices and its implication for emergency obstetrics care in azare, north-eastern Nigeria.

BACKGROUND: Consent practices can affect the institution of emergency obstetrics care in the health facility, and may indeed, determine the degree of maternal mortality and morbidity. OBJECTIVES: This study was aimed at determining informed consent practices and its implication for Emergency Obstetrics Care (EOC). METHODS: A cross-sectional study involving 787 women who presented with obstetric emergencies at the FMC Azare from 1(st) January 2008 to 31(st) December 2009 was done. The sociodemographic characteristics and birth outcome were compared between those that gave early consent (EC) and those that gave delayed consent (DC). Data was analysed using SPSS version 11. Morbidities and mortalities were compared in the two groups and P < 0.05 was considered statistically significant. RESULTS: EC for obstetric intervention was obtained in 260 (33.0%) of the cases, while 527 (66.0%) gave DC. The mean length of time for DC was 4.5 ± 3.5 hours (Range 1.25 to 72 hours). In 62.9% of cases the consent was given by the husband while the patient consented in 5.6%. In-laws, relatives and others were responsible for 13.8%, 8.5%, 5.7% and 3.5% respectively. Consent was significantly delayed when given by the husbands, in-laws and relatives. Patients that gave consents for their own treatment were more likely to be gainfully employed (P=0.019), educated (P=0.004) and booked (P=0.001). Maternal mortality, intrauterine fetal death, low Apgar scores and early neonatal death were significantly increased in the DC group with P values of 0.016, 0.032 and 0.026 respectively. CONCLUSION: Delay in giving Consent contributes significantly to maternal and fetal morbidity and mortality in our environment because it increases the 3(rd) level of delay.

Prevalence, risk factors and effects of placental malaria in the UMTH, Maiduguri, North-eastern, Nigeria: a cross-sectional study.

SUMMARY: Most of the adverse effects of malaria in pregnancy on the fetus are usually as a consequence of placental malaria (PM). This study was conducted with the objective of determining the prevalence, risk factors and pregnancy outcome of PM. A cross-sectional study of 437 pregnant women who delivered at the UMTH, Maiduguri was conducted between 24 July 2007 and 12 January 2008. Placental histology was done for the malaria parasite. Maternal packed cell volume was done and thick blood films were studied for the malaria parasite in maternal peripheral blood and the cord blood/heel prick of their babies. The prevalence of PM was 33.9% (148/437). It is associated with non-usage of intermittent preventive treatment of malaria in pregnancy (IPT) and maternal HIV infection. PM in turn predisposes to low birth weight and cord parasitaemia. Only 2.8% of the women were sleeping under insecticide-treated nets (ITNs). The high prevalence of PM calls for renewed efforts for preventive measures, particularly the routine use of IPT and ITN during the antenatal period.

Emergency obstetrics care in a Nigerian tertiary hospital: a 20 year review of umblical cord prolapse.

CONTEXT: Umbilical cord prolapse is an obstetric emergency associated with high perinatal morbidity and mortality unless prompt delivery by the fastest and safest route is carried out. OBJECTIVES: To determine the incidence of umbilical cord prolapse, predisposing factors, and fetal outcome. STUDY DESIGN, SETTING AND SUBJECTS: A 20 year retrospective study of all women who presented with umbilical cord prolapse at University of Maiduguri Teaching Hospital, Maiduguri, North-Eastern Nigeria. RESULTS: During the study period there were 27,753 deliveries and 75 women had cord prolapse, giving the incidence of 1 in 370 deliveries (0.27%). Significantly more patients with non vertex presentation, twins and preterm delivery had cord prolapse. The highest occurrence was in those with unengaged presenting part (65.2%), spontaneous rupture of membrances (62.1%) and grandmultiparous women (57.6%). Caeserean section was carried out in 50% of cases, with mean decision-delivery interval of 77.1 +/- 21.7 minutes and 28/33 (84.9%) of babies delivered within 60 minute had normal Apgar scores. The Knee-chest position was most commonly used method of alleviating cord compression while arrangement for caesarean section was being made. The perinatal mortality was 27.3%. CONCLUSION: umbilical cord prolapse is a brisk obstetric emergency with high perinatal morbidity and mortality unless prompt delivery is undertaken. Better communication and prompt response to emergency by the theatre team to reduce the decision-delivery interval would improve the perinatal outcome.

Effectiveness of Manual Vacuum Aspiration (MVA) in the Management of First Trimester Miscarriage: Experience in a Specialist Centre in North-Eastern Nigeria

Background: Safe management of abortion with an easy; simple and effective procedure is mandatory to minimise abortion related morbidities and mortalities. Aim: To assess the pattern of presentation of cases of first trimester miscarriage and the value of manual vacuum aspiration (MVA) in the management of abortion. Methods: Clinical records of 251 cases of miscarriage managed over a 3-year period 2005 - 2007 using MVA ipas aspirator were retrieved and information pertaining to age parity; gestational age at presentation; indication for MVA use; duration of hospital stay and complications encountered were retrieved for analysis and interpretation. Results: A total of 1899 gynaecological procedures were carried out over the 3-year period; out of which 251 were MVA procedures performed for various first trimester miscarriages; accounting for 13.2of the total gynaecological admissions. Sixty one (24.3) of the patients who benefited from MVA were in the 25-29 years age group; while those in the age 20-24 and 30-34 years group constituted 21.5and 20.7respectively. Grandmultiparas (53.7) constituted the majority. The procedure was performed for 50.2of the patients at 9-11 wks of gestation. Most (88.0) of the patients had the procedure performed for incomplete abortion and while the remaining 12.0were for check MVA after complete abortion and missed abortion. Most (67) of the cases were perform as outpatient procedures. There were three maternal deaths which were not related to the procedure. Conclusions: First trimester miscarriage appeared to be most common among grandmultipara and during the 9-11weeks of gestation. Most of the patients fell into the 25-29 years age group. It appears MVA is being effectively utilized in our centre

Attitude of Nigerian women to contraceptive use by men.

This study was aimed at finding the attitude of Nigerian women to contraceptive use by their male partners. A total of 417 women received the questionnaire; 71% of these were sexually active and 34.8% were not aware of any male contraceptive method. Only 1.7% reported regular use of condoms by their spouses, however this was significantly higher if the women were better educated. Most of the women had a positive attitude to contraceptive use by their spouses, as 54% (225/417) of them showed preference to male dependant contraceptives in their relationship. However, only 32.3% (135/417) of the women had ever-requested their spouse to use a condom and in just 18.5% (25/135) was such a request regularly complied with. Significantly more Muslim women prefer their partners to use a contraceptive rather than themselves (p = 0.001), but the condom usage by their spouses is significantly lower than their Christian counterparts (p = 0.000). There is a need to offer counselling on male contraceptives to both genders so that they can make an informed choice, especially with the dual protection offered by the use of condoms.

Methods of induction of labour at the University of Maiduguri Teaching Hospital, Maiduguri: a 4-year review.

BACKGROUND: Induction of labour is an important intervention in obstetrics. Misoprostol is increasingly being used for induction of labour in many obstetric units and it may replace the traditional Foleys catheter/oxytocin protocol. METHOD: This was a retrospective study of the 3 methods of induction of labour used at the University of Maiduguri Teaching Hospital (UMTH). A total of 468 women had induction of labour during the study period. Two hundred and twenty eight of them had induction with 50 microg of misoprostol, 57 women had 100 microg of misoprostol while 183 women had extra-amniotic Foleys catheter with oxytocin infusion. RESULT: Induction of labour constituted 6.6% (468/7086) of all deliveries during the study period. The commonest indication for induction of labour was prolonged pregnancy in 46.8%, followed by pregnancy induced hypertension in 33.5%. There was no difference in the achievement of vaginal delivery between the 3 methods of induction of labour (chi2 = 1.13, p = 0.57). The mean induction delivery time was shortest for those induced with 100 microg of misoprostol (6.38 +/- 2.25 hours), followed by 8.16 +/- 3.58 hours in those induced with 50 ug of misoprostol and 9.73 +/- 4.32. 43 hours in those induced with Foleys catheter/oxytocin (p < 0.001). The babies delivered to women induced with 100 microg of misoprostol were more asphyxiated 12.3% (7/57) compared to 9.2% (21/228) and 6.6% (12/183) in the 50 ug misoprostol and Foleys catheter/oxytocin respectively and was statistically significant (chi2 = 23.08, p = 0.01). The short induction delivery time in the group with 100 microg of misoprostol was advantageous but there was an associated higher risk of birth asphyxia, stillbirth, uterine hyperstimulation, perineal tear and uterine rupture. The normal delivery outcome was not significantly different from those induced with 50 microg of misoprostol and those induced with Foleys catheter/oxytocin (chi2 = 1.24, p = 0.94). Normal delivery rate was significantly higher in those induced with 50 microg of misoprostol compared with those induced with 100 microg of misoprostol (chi2 = 14.38, p = 0.01). CONCLUSION: Misoprostol appears to be safe and may be a suitable alternative for induction of labour by the traditional Foleys catheter/oxytocin protocol. The 50 microg dosing of misoprostol is safer than the 100 microg.

Methods of Induction of Labour at the University of Maiduguri Teaching Hospital, Maiduguri: A 4-Year Review

Background: Induction of labour is an important intervention in obstetrics. Misoprostol is increasingly being used for induction of labour in many obstetric units and it may replace the traditional Foleys catheter/oxytocin protocol. Method: This was a retrospective study of the 3 methods of induction of labour used at the University of Maiduguri Teaching Hospital (UMTH). A total of 468 women had induction of labour during the study period. Two hundred and twenty eight of them had induction with 50?g of misoprostol; 57 women had 100?g of misoprostol while 183 women had extra-amniotic Foleys catheter with oxytocin infusion. Result: Induction of labour constituted 6.6(468/7086) of all deliveries during the study period. The commonest indication for induction of labour was prolonged pregnancy in 46.8; followed by pregnancy induced hypertension in 33.5. There was no difference in the achievement of vaginal delivery between the 3 methods of induction of labour (x2=1.13; p=0.57). The mean induction delivery time was shortest for those induced with 100?g of misoprostol (6.38+2.25 hours); followed by 8.16+3.58 hours in those induced with 50ug of misoprostol and 9.73+4.32.43 hours in those induced with Foleys catheter/oxytocin (p

Dislocation glasses: aging during relaxation and coarsening.

The dynamics of dislocations is reported to exhibit a range of glassy properties. We study numerically various versions of 2D edge dislocation systems, in the absence of externally applied stress. Two types of glassy behavior are identified (i) dislocations gliding along randomly placed, but fixed, axes exhibit relaxation to their spatially disordered stable state; (ii) if both climb and annihilation are allowed, irregular cellular structures can form on a growing length scale before all dislocations annihilate. In all cases both the correlation function and the diffusion coefficient are found to exhibit aging. Relaxation in case (i) is a slow power law, furthermore, in the transient process (ii) the dynamical exponent z approximately 6, i.e., the cellular structure coarsens relatively slowly.

Dislocation patterning: from micro- to mesoscale description

During the plastic deformation of crystalline material the dislocations, being the carriers of the plastic flow, tend to form different patterns. Because of the long range nature of dislocation-dislocation interaction, the origin of this self-ordering phenomenon is still an open question. The paper presents a stochastic two-dimensional model derived directly from the properties of individual dislocations making it possible to investigate the problem on a mesoscale. Numerical results obtained in double slip configuration indicate the development of cell structure with fractal character.

Detailed analysis of a nonlinear prey-predator model.

A model of competition between populations of two species, describedby a two dimensional map, is analytically and numerically studied. A rich dynamics is observed.

The dripping faucet revisited.

High accuracy experimental results on the nonlinear dynamical behaviour of a dripping faucet are presented. The distribution functions for droplet sizes and drip intervals together with return maps are studied for various dripping rates. Increasing this control parameter, chaotic behaviour is obtained and discussed. (c) 1996 American Institute of Physics.

[Mammographic mass examinations for breast cancer among rural population selected via physical examination and epidemiologic questionnaire (author's transl)]. / Mammographische Brustkrebs-Reihenuntersuchungen bei mit physikalischer Untersuchung und epidemiologischem Fragebogen selektierter Bevölkerung vom Lande.

The authors report on their four years' experience in oncologic mass examinations focused on the age group above 30. After 43980 serial examinations, they performed mammography in 3082 women with mammary cancer risk. 156 operations were performed, and 33 histologically established cases of mammary carcinoma were recorded, with 21 early-stage cases. Of 21 occult tumors, 18 did not manifest any metastases. Thanks to the epidemiologic questionnaire, 10 mammary cancer patients were registered. The score of confirmed findings exceeded quantitatively, and, especially, qualitatively, the mammary carcinoma morbidity of the region. The results prove the feasibility of the combined method. The major part of the population did not appear for mass examination. The advanced stage of the 55 cases of breast cancer belonging to this group, as well as that of the 10 cases of which became manifest during the examination interval, would indicate that much is to be said for a more effective health promotion campaign among the population.