Method Of Age Determination Research Articles

Age and Growth Estimations of Decapterus Kurroides Using Otolith in the Waters of Eastern Taiwan

Aims: Redtail scad (Decapterus kurroides Bleeker, 1855) was once an economically important Carangidae species in Taiwan. This study determined age using otolith increments and re-evaluated the parameters of growth equations for this species.
 Place and Duration of Study: Fish samples were collected monthly off the coast of Taitung, eastern Taiwan.
 Methodology: A total of 367 specimens were observed in this study. To determine fish age, otolith age determination method was used. The largest and smallest otolith rings were seven and two, and their corresponding means of fork length (FL) were 29.2 and 12.2 cm, respectively.
 Results: Most samples had six otolith rings with a mean FL of 27.2 cm. The von Bertalanffy growth equation is FLt = 30.44 (1 – e −0.52 (t - 1.50)) for females and FLt = 32.45 (1 – e −0.39 (t – 1.18)) for males. The otolith opaque zone annually formed from September to October. The relationship of body weight (BW) and Fork Length (FL) differed significantly between genders: BW = 0.334 × 10-2 FL3.463 for females and BW = 0.469 × 10-2 FL3.349 for males. The sex ratio was 0.56 over a whole year and varied among the age groups.
 Conclusion: This study using the otolith method revises the estimations of age and growth parameters for the D. kurroides, which would be beneficial to manage and recover this species stock in the waters of Taiwan.

Age structure and growth pattern of a high-altitude lizard population based on age determination by skeletochronology.

Age determination provides crucial data regarding the life history of a species. Skeletochronology is considered to be a reliable method for age determination but is seldom applied to the genus Phrynocephalus (Agamidae) as it requires careful bone histological analysis to determine the formation of the lines of arrested growth (LAGs). We analyzed LAGs in different bones of Phrynocephalus vlangalii, a small, high-altitude lizard, and demonstrated that the phalanges are the best materials for skeletochronology in this species. We also found that the proximal half of the phalangeal diaphysis exhibits the most complete LAGs because of the unidirectional longitudinal growth of the phalange. Histologically, as the embryo bone that developed during the embryonic period was preserved even in very old individuals, no LAGs were eroded by endosteal resorption in the phalanges. The maximum age was 4yearsfor males and 5years for females. It was determined that the age at maturity was 3years for males and 2 or 3years for females. On the basis of age determination, the age structures of both sexes were compared, and age-specific growth differences between the sexes were also analyzed. No differences in the snout-vent length were observed between sexes in any age group. However, the tail length of males aged 3 and above was significantly longer than that of females. Thus, the use of phalanges in the age determination of P. vlangalii is effective and can be widely applied to the ecological studies of this species as well as other small lizards.

Logistic Regression Model for Determination of the Age of Brown Hare (Lepus europaeus Pall.) Based on Body Weight.

Simple SummaryBecause the determination of the age of brown hares (Lepus europaeus) is difficult, we developed a method for age determination on the basis of animal body weight. On the basis of the results of postmortem analysis of body weight and eye-lens weight, which provide reliable information on the change in these parameters with age, a logistic regression model was developed to classify brown hares as either juveniles (up to one year old) or adults (more than one year old), with a body weight of 4.227 kg as the limiting interval. With an accuracy of 95%, this noninvasive method can be used in both scientific research and population management.We developed an algorithm to classify brown hares into two age classes, juveniles (up to 1 year old) and adults (over 1 year old), based on body weight, which can be determined by both the examination of live animals and postmortem analysis. Considering the strong correlation between lens weight and carcass weight, we assumed that hares could be classified into one of the two age groups based only on carcass weight, using a logistic regression model. Using logistic regression, a model was constructed to assess the age of hares based on their body weight. For comparison with the current age-assessment method based on the dry lens weight, a logistic regression classifying the hares based on the dry lens weight was performed as well. The results of the study facilitated the development of a method to classify hares into age groups based on body weight. The proposed approach is innovative, as it allows for the determination of the age of not only culled (postmortem) but also live hares. The method is easy and does not require laboratory tests; hence, the results can be used immediately following evaluation. This method allows hares to be categorized into two age groups (juveniles and adults). With an accuracy of 97.52% and 95.45% in the case of juvenile and adult hares, respectively, the proposed approach can be widely used both in population management and scientific research.

Coarse-to-fine segmentation and ensemble convolutional neural networks for automated pediatric bone age assessment

Bone age assessment is commonly used to estimate bone maturity and diagnose disease in children and adolescents. It is significant to develop intelligent bone age estimate methods for clinical applications. In this paper, we propose a novel two-stage automated pediatric bone age assessment method, which cascades a coarse-to-fine hand segmentation method and stacking-based ensemble convolutional neural networks (CNNs). Specifically, we use density-based spatial clustering of applications with noise algorithm to extract coarse feature points of interest from preprocessed hand radiographs. Afterward, we construct a U-Net to fine hand masks, which facilitates feeding clean pediatric hand bone radiographs into the following ensemble CNNs classifier to produce accurate skeletal age estimate. Considering the complementary feature extraction capabilities of different networks, we design an ensemble learning model by stacking five powerful CNNs to improve bone age assessment accuracy from clean hand radiographs. We evaluate the proposed two-stage bone age estimate method using both public and clinical datasets. Experimental results show that our method outperformed existing state-of-the-art skeletal age determination methods and respectively achieved the mean absolute error of 5.42 and 5.98 months on males and females.

Characterization of young Californium sources by means of [formula omitted]-ray spectroscopy

The spontaneous fission and neutron emission properties of Californium sources serve as a unique tool to analyze and validate the quality of detection of fission products. State-of-the-art methods for determining the age of a young Cf source were re-examined and modified. Further improvement included the determination of the single Cf isotopes within the Cf source and the neutron emission rate of the source.The analysis was performed by comparing the simulated γ-ray spectra of the Nucleonica suite with measured data of a young Cf source employing an HPGe detector. In addition, with the evaluation of the 133.5 keV peak (mainly due to the β-decay Ce-144/Pr-144) in relation to a peak at 497.1 keV (mainly due to the β-decay Ru-103/Rh-103) or 724.3 keV (multiplet, dominated by Ru-105/Rh-105 and Ce-145/Pr-145), the age-determination method of the investigated Cf source could be considerably improved to a confined age of 20 ± 3 months.By means of decay simulations, some deficiencies of current techniques in determining the isotope abundances were introduced. In particular, the quantities of Cf-252 and Cf-249 were analyzed extensively. Consequently, the source’s neutron emission rate matched well the emission rate from the source’s certification. The difficulties of defining the abundance of additional Cf isotopes within the source, albeit with lesser importance, are also illustrated.

Paediatric skull growth models: A systematic review of applications to normal skulls and craniosynostoses

Craniosynostoses affect 1/2000 births and their incidence is currently increasing. Without surgery, craniosynostosis can lead to neurological issues due to restrained brain growth and social stigma due to abnormal head shapes. Understanding growth patterns is essential to develop surgical planning approaches and predict short- and long-term post-operative results. Here we provide a systematic review of normal and pathological cranial vault growth models. The systematic review of the literature identified descriptive and comprehensive skull growth models with the following criteria: full text articles dedicated to the skull vault of children under 2 years of age, without focus on molecular and cellular mechanisms. Models were analysed based on initial geometry, numerical method, age determination method and validation process. A total of 14 articles including 17 models was reviewed. Four descriptive models were assessed, including 3 models using statistical analyses and 1 based on deformational methods. Thirteen comprehensive models were assessed including 7 finite element models and 6 diffusion models. Results from the current literature showed that successful models combined analyses of cranial vault shape and suture bone formation. Growth modelling is central when assessing craniofacial architecture in young patients and will be a key factor in the development of future customized treatment strategies. Recurrent technical difficulties were encountered by most authors when generalizing a specific craniosynostosis model to all types of craniosynostoses, when assessing the role of the brain and when attempting to relate the age with different stages of growth.

Fetal kidney length: A likely sole index for gestational age determination in late pregnancy and certain abnormalities

Background: The Obstetric management of a pregnancy relies on the knowledge of an accurate gestational age especially in unregistered cases. Aims: The aim of this study was to sonographically evaluate the fetal kidney length as a potentially dependable direct measurement parameter, to estimate gestational age in the second and third trimesters. Patients, Materials and Methods: The study involved 236 participants with 20 to 34 weeks pregnancies, referred to the Radiology department of the University of Calabar teaching hospital for obstetric ultrasound scan, within a three-month period. The fetal kidney lengths were measured, in addition to the routine parameters, which included head circumference and femur length. The estimated gestational ages derived from the routine parameters, were correlated with the kidney and femur lengths and head circumference. The data were analyzed using SPSS version 22.0. Results: Fetal kidney length increased in direct proportion to gestational age. It had a significant positive correlation coefficient (0.982) with the estimated gestational age, similar to the head circumference and femur length. Fetal kidney lengths in millimeters were nearly equal to the estimated gestational ages in weeks, especially from the thirtieth week. Conclusion: Fetal kidney length is a viable, simple and direct method for determination of gestational age of pregnancies in the second and third trimesters. Since fetal kidney length assessment is said to remain reliable after 34 weeks, unlike the head circumference and femur length, it can serve as the sole index of gestational age assessment late in pregnancy, especially in fetal structural abnormalities.

Significance of dental age assessment in forensic science: A review

Age assessment is the preliminary step in the positive identification of an individual. It is considered as one of the essential and frequently utilized method by the forensic anthropologists or forensic odontologists to determine the approximate age of living or deceased. There are certain circumstances when the chronological age of an individual or subject is missing, or chronological age needs to be verified in case of juvenile delinquency. Moreover, age determination can be made possible in the positive identification of victims of mass disasters, illegal immigration of juveniles, child marriage, imprisonment of juveniles, as well as in orthodontic treatment. Certain methods like radiographic assessment, physiological assessment, morphological assessment of teeth and bones have been implemented to assess age of such individuals. It is hard to utilized one-specific method for age determination due to variation in population size, variation in dietary habits, variation in growth and development. The appraisal has been formulated to assess age by radiographic method as it is user-friendly, quick to access and could considered to be more reliable as compared to physiological method,yet most such age-assessing frameworks are based on European population and their pertinence has still up in the air with regards to the Indian population.

A CASE FOR DIFFEREN A CASE FOR DIFFERENT STANDARDS IN A ARDS IN AGE DETERMINATION PROCEEDINGS

The absence of a clear statutory process for age determination of victims has resulted in inconsistent judicial outcomes that lack a principled approach and dilute the standard of proof requirements intrinsic to criminal trials. This paper explores the feasibility of transposing the method for age determination of an offender provided under the Juvenile Justice Acts to the determination of the age of a victim in the context of criminal trials where the victim’s age creates a new substantive offence. This, it is argued, is inconsistent with the text of the various Juvenile Justice Acts, their purpose, and judicial precedent. The paper explores the nature of these inconsistencies as they occur during the process of age determination in criminal trials and finds that the variations are a result of differences in the understanding and application of the law. The paper argues that the standard of proof for determining the age of a child in conflict with law cannot be applied to determine the age of a victim and the latter needs to adhere to a higher evidentiary standard given its bearing upon the rights of an accused.

Growth during times of fear and emotional stress

Twenty-one scientists met for this year’s virtual conference on Auxology held at the University Potsdam, Germany, to discuss child and adolescent growth during times of fear and emotional stress. Growth within the broad range of normal for age and sex is considered a sign of good general health whereas fear and emotional stress can lead to growth faltering. Stunting is a sign of social disadvantage and poor parental education. Adverse childhood experiences affect child development, particularly in families with low parental education and low socioeconomic status. Negative effects were also shown in Indian children exposed prenatally and in early postnatal life to the cyclone Aila in 2009. Distrust, fears and fake news regarding the current Corona pandemic received particular attention though the effects generally appeared weak. Mean birth weight was higher; rates of low, very and extremely low birth weight were lower. Other topics discussed by the participants, were the influences of economic crises on birth weight, the measurement of self-confidence and its impact on growth, the associations between obesity, peer relationship, and behavior among Turkish adolescents, height trends in Indonesia, physiological neonatal weight loss, methods for assessing biological maturation in sportsmen, and a new method for skeletal age determination. The participants also discussed the association between acute myocardial infarction and somatotype in Estonia, rural-urban growth differences in Mongolian children, socio-environmental conditions and sexual dimorphism, biological mortality bias, and new statistical techniques for describing inhomogeneity in the association of bivariate variables, and for detecting and visualizing extensive interactions among variables.

State-of-Art in the Age Determination of Venous Thromboembolism: A Systematic Review.

Venous thromboembolism (VTE), consisting of deep vein thrombosis (DVT) and pulmonary embolism (PE), requires a forensic age determination to ascertain their causal relationship with recent events, such as trauma or medical treatment. The main objective of this systematic review is to identify the current state-of-the-art immunohistochemical methods for age determination of fatal VTE. A literature search was performed through different databases, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Within the study, we have selected only cases represented by deceased patients for DVT and/or PTE in which thromboembolic material was collected during an autoptic examination and then subjected to a histological and an immunohistochemical investigation. Studies based on animal models were not included. We assessed bias risk. A database-based search produced a total of 19 articles. After excluding duplicate items from the selection, 14 articles were reviewed. Ten articles were excluded because they did not meet the inclusion criteria. The results have pointed out 4 studies that were included in the present analysis for a total of 157 samples of DVT and 171 PTE samples. These were analyzed using traditional histological and immunohistochemical techniques. The results must be interpreted with a critical eye because of their heterogeneity in terms of time, geography, and study design. The present review highlights the importance of associating specific immunohistochemical markers with a histological analysis for the timing of DVT/PTE fatal events. Further future experiences will hopefully endorse actual knowledge on the subject to increase the accuracy in the assessment of thrombus-embolus age.

Paleoproterozoic Pt-Pd Fedorovo-Pansky and Cu-Ni-Cr Monchegorsk Ore Complexes: Age, Metamorphism, and Crustal Contamination According to Sm-Nd Data

This paper continues the Sm-Nd isotope geochronological research carried out at the two largest Paleoproterozoic ore complexes of the northeastern Baltic Shield, i.e., the Cu-Ni-Cr Monchegorsk and the Pt-Pd Fedorovo-Pansky intrusions. These economically significant deposits are examples of layered complexes in the northeastern part of the Fennoscandian Shield. Understanding the stages of their formation and transformation helps in the reconstruction of the long-term evolution of ore-forming systems. This knowledge is necessary for subsequent critical metallogenic and geodynamic conclusions. We applied the Sm-Nd method of comprehensive age determination to define the main age ranges of intrusion. Syngenetic ore genesis occurred 2.53–2.85 Ga; hydrothermal metasomatic ore formation took place 2.70 Ga; and the injection of additional magma batches occurred 2.44–2.50 Ga. The rock transformation and redeposited ore formation at 2.0–1.9 Ga corresponded to the beginning of the Svecofennian events, widely presented on the Fennoscandian Shield. According to geochronological and Nd-Sr isotope data, rocks of the Monchegorsk and the Fedorovo-Pansky complexes seemed to have an anomalous mantle source in common with Paleoproterozoic layered intrusions of the Fennoscandian Shield (enriched with lithophile elements, εNd values vary from −3.0 to +2.5 and ISr 0.702–0.705). The data obtained comply with the known isotope-geochemical and geochronological characteristics of ore-bearing layered intrusions in the northeastern Baltic Shield. An interaction model of parental melts of the Fennoscandian layered intrusions and crustal matter shows a small level of contamination within the usual range of 5–10%. However, the margins of the Monchetundra massif indicate a much higher level of crustal contamination caused by active interaction of parental magmas and host rock.

Data Enhancement and Deep Learning for Bone Age Assessment using The Standards of Skeletal Maturity of Hand and Wrist for Chinese.

Conventional methods for artificial age determination of skeletal bones have several problems, such as strong subjectivity, large random errors, complex evaluation processes, and long evaluation cycles. In this study, an automated age determination of skeletal bones was performed based on Deep Learning. Two methods were used to evaluate bone age, one based on examining all bones in the palm and another based on the deep convolutional neural network (CNN) method. Both methods were evaluated using the same test dataset. Moreover, we can extend the dataset and increase the generalisation ability of the network by data expansion. Consequently, a more accurate bone age can be obtained. This method can reduce the average error of the final bone age evaluation and lower the upper limit of the absolute value of the error of the single bone age. The experiments show the effectiveness of the proposed method, which can provide doctors and users with more stable, efficient and convenient diagnosis support and decision support.

Allogeneic Hematopoietic Cell Transplantation Causes Accelerated Aging Both of the Hematopoietic and Somatic Systems

Recent reports suggest that survivors of hematopoietic cell transplantation (HCT) exhibit clinical features consistent with accelerated aging including increased incidence of endocrinological, pulmonary and cardiovascular morbidity, other severe chronic disorders and excess of secondary malignancies. In addition, high incidence of frailty - a physiologic measure of aging, was documented in childhood cancer survivors. Data from additional studies suggest that cytotoxic therapy triggers an acceleration of the aging process whose likely mechanism may be cellular senescence. In order to corroborate the physiological and epidemiological data, more accurate biological markers of senescence should be assessed. Indeed, several studies, including from our group, reported on telomere shortening after HCT. Other studies showed elevation of inflammatory biomarkers, those being associated with the aging process. The accuracy of these biological markers is disputable due to inherent problems in their interpretation. Recently, several more accurate biomarkers of cellular age have been reported. The most promising is the DNA methylation status of several genomic loci, which can determine the cellular age with accuracy of 1.5 to 3 years. Additional markers, such as p16ink4A and IL-6 concentrations in serum are also considered as reliable markers of age.The present study assessed the hematopoietic and non-hematopoietic systems aging trajectory after allogeneic HCT. We took advantage of being able to assess quantitatively the hematopoietic system comparing blood cells derived from one person (the donor) and residing in two different hosts (donor and recipient). The blood cells aging may be affected by replicative stress after HCT and therefore do not necessarily represent the whole body aging; therefore we measured the age of buccal epithelial cells of the transplant survivors as well. For cellular age determination we used DNA methylation in three sites, previously validated as an accurate age determination method, p16ink4A blood levels and serum IL-6 concentration. To the best of our knowledge, this is the first study employing these novel markers for assessment of accelerated aging in a clinical setting.26 survivors of allogeneic HCT (median age, 48 years; range, 28 to 71) were evaluated at a median of 3.6 (range, 2.2 to 9) years after HCT. The cellular age of donor blood cells residing in the recipient was compared with the age of the blood cells residing in the respective donor and the cellular age of the patients' buccal epithelial cells was compared with their chronological age.In 21 out of 26 patients the cellular age of donor blood cells residing in the patients was significantly higher than that of the respective cells residing in the donor as determined by DNA methylation. The mean excess aging of the cells was 8.3 (range -5 to 30) years and in most of the patients the cells were more than 10 years “older” than the donors' cells. The buccal epithelial cells predicted age was also significantly higher than the chronological age; the median excess of aging was 8.7 (range, -37 to 10.5) years. The two other biomarkers of aging: IL-6 and p16ink4A also demonstrated advanced age compared to the chronological age. There was no association between the magnitude of aging and previous chemotherapy or GVHD. Telomere length was not significantly shortened in the transplanted patients compared to their donors, consistent with previous reports demonstrating initial telomere shortening and eventual return to normal levels.In conclusion, allogeneic stem cell transplantation is associated with significant accelerated aging of both of the hematopoietic and somatic systems. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Keeping an eye on the use of eye-lens weight as a universal indicator of age for European wild rabbits

Accurate methods for age determination are critical to the knowledge of wildlife populations' age structure and, therefore, to their successful management. The reliability of age estimation may have profound economic and ecological consequences on the management of the European wild rabbits, Oryctolagus cuniculus, in its native and introduced range, where it is a keystone species and a major pest, respectively. As in other mammal species, European rabbits' age is often estimated using the Gompertz relationship between age and lens' weight. The growth rate formula has been developed based on data collected from European rabbits introduced in Australia, where a single subspecies (O. cuniculus cuniculus, Occ) is present. However, this curve has never been validated in the species native range, the Iberian Peninsula, where two subspecies (Occ, and O. c. algirus, Oca) coexist naturally. In this study, we tested the relationship between age and lens' weight using 173 Occ and 112 Oca wild rabbits that were surveyed in two experimental facilities in Spain. Our findings show that, in the native range, the published growth curve formula fits well Occ but not Oca data. Therefore, we recommend using the formula reported in this study to estimate the age of Oca (Lens dry weight = 240 × 10(−64.9/(Age+32))). This study supports Oca rabbits' distinctiveness revealed by previous studies, which suggests that management interventions should be applied to protect this subspecies whose distribution range is very narrow and whose populations seem to be declining. More broadly, our findings point to the importance of testing the suitability of growth curves defined for other species with different genetic forms as occurs in the European wild rabbit case.

An Exploratory Study of Telomere Length in the Deep-Sea Shark, Etmopterus granulosus

The history of elasmobranch ageing highlights the difficulty of age estimation in animals lacking ossified structures. Ageing techniques are numerous, yet all are limited by difficulties of validation and verification and inherent subjectivity. Sample scarcity further hinders progress as limited samples cannot be risked on exploratory techniques. This study explored the use of genetic analysis of telomeres as a method of age determination in a deep-sea shark, Etmopterus granulosus, a representative of a poorly studied taxon with regard to ageing due to sample scarcity. Telomeres were amplified in 39 individuals with qPCR, compared across samples, and were found to differ across size classes. More work is needed to determine whether telomeres consistently correlate with size class across elasmobranchs. However, telomeres offer easily obtainable data that can be combined with traditional methods to provide additional points of comparison for elasmobranch biology. Our results underscore the importance of expanding current ageing methods and highlight a necessary distinction between chronological and biological ages when describing elasmobranch populations.

Age, Growth and Ovarian Histology of Sardinella aurita (Valenciennes, 1847) in the South of Atlantic Moroccan Coast

Otoliths reading and length frequency distribution were used for age determination and growth estimation of Sardinella aurita (round sardinella) stock of Southern Atlantic coast of Morocco. Both otoliths' method for age determination and Bhattacharya’s method for length frequency analysis showed five age groups. The growth performance index revealed that there is significant accordance among method of length frequency distribution and otoliths reading for stock assessment studies of Sardinella aurita stock in the south of Morocco. The microscopic observation of female gonads using histology method was investigated for the first time in our study area and confirms the presence of five principal stages of ovary of sardinella aurita: immature, maturing virgin and recovering spent, mature (or pre-spawning phase), spawning, post-spawning or spent. In addition, our results of the fecundity showed that the mean relative fecundity obtained is estimated at 193 ± 98 oocytes/g which is lower compared to those obtained in other areas in the Atlantic coast.

A retrospective institutional study of human age determination by evaluating the pulp length and width ratio of the maxillary lateral incisor on panoramic radiographs in Indonesian subjects

PurposeThe pulp length to width (PL/W) ratio of the maxillary lateral incisor can be used as an age determination method. This study aimed to investigate the correlation between the PL/W ratio of the maxillary lateral incisor on panoramic radiographs and human chronological age in Indonesian subjects.Materials and MethodsThis study analyzed with 134 maxillary lateral incisors on 113 panoramic radiographs from patients who visited the Oral and Maxillofacial Radiology Unit of Dental Hospital Universitas Padjadjaran, Bandung, Jawa Barat, Indonesia, from 2013 to 2018 (age range: between 11 to 60 years). The pulp length was measured from the pulp chamber roof to the apical foramen, and the pulp width was measured on the cervical area of the cementoenamel junction in millimeters using Fiji ImageJ open-source software. Simple linear regression (in SPSS) was used to analyze the results. The reliability of the observers was evaluated.ResultsThe PL/W ratio of the maxillary lateral incisor was significantly correlated with chronological age (P<0.01). No statistically significant difference was found in the PL/W ratio between the left and right maxillary lateral incisors (P=0.333). There was a very strong correlation (r=0.939) between the PL/W ratio of the maxillary lateral incisor and human chronological age, with the following formula: age= -3.057+1.875×PL/W ratio (R2=0.882, standard error of estimate: 4.659).ConclusionThe PL/W ratio of the maxillary lateral incisor on panoramic radiograph can be used for age determination in Indonesian subjects.

Reference charts of birth weight and birth length by gestational age in south east Serbian newborns: Preliminary results

Background/Aim. To date, there has been no population-based neonatal anthropometric chart published in Serbia. Charts based on infants born in a single hospital (hospital-based) in the 1 990s are still widely used in our country, as well as the Alexander chart. The aim of this study was to construct population-based centile, gender-specific charts for birth weight and length for singleton infants born in Southeast Serbia from 24 t o 42 weeks of gestation and to compare them with other previously published charts. Methods. Data on 39,842 singleton live infants, delivered from 2006 to 2015 in three maternity wards in Southeast Serbia (Nis, Prokuplje, and Aleksinac), were analyzed. Results. The inclusion criteria met 37,169 newborns. Preterm births were relatively uncommon (5.25%). Estimated centile charts for male and female birth weights and lengths were constructed showing the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th centiles. Conclusion. Our birth weight percentiles provide a population norm for singleton infants adjusted for gender, born in Southeast Serbia. These references are both of epidemiological and clinical use. There is a need for large-scale research that will include a larger number of pre-term newborns which were represented in limited numbers in our study. There is also a need for setting up the gold standard method for the precise determination of the gestational age, i.e. the use of the early fetal ultrasound.

The growth and age structure of Chilean jack mackerel (Trachurus murphyi) following its influx to New Zealand waters

The Chilean jack mackerel (Trachurus murphyi) is a predominantly Southeast Pacific Ocean species. It is relatively difficult to determine its age, and multiple studies of its growth off South America have produced markedly different sets of von Bertalanffy parameters. T. murphyi was first identified from New Zealand waters in the mid-1980s and has comprised part of the commercial landings of Trachurus species (along with Trachurus declivis and Trachurus novaezelandiae) since then. Results from 13 years of age determination of New Zealand samples using sectioned otoliths indicate that a partially validated age determination method has been developed, with a precision level (average percentage error) of 4.6%. The best available von Bertalanffy growth parameters for the New Zealand population (sexes combined) are as follows: L∞ , 51.9 cm fork length; K, 0.223 per year; t0 , -0.5 year. Analyses by sex showed that males have a significantly larger L∞ than females. Estimated annual catch-at-length and catch-at-age distributions from the fishery are presented for 2007-2019. There have been at least two episodes of immigration of T. murphyi from international waters, but little evidence of spawning success to maintain the New Zealand population.