The culling of day-old male chicks has caused ethical and economic concerns. Traditional approaches for detecting the in ovo sex of chicken embryos involve opening the eggshell and inner membrane, which are destructive, time-consuming, and inefficient. Therefore, noncontact optical sensing techniques have been examined for the in ovo sexing of chicken embryos. Compared with traditional methods, optical sensing can increase determination throughput and frequency for the rapid sexing of chicken embryos. This paper presented a comprehensive review of the different optical sensing techniques used for the in ovo sexing of chicken embryos, including visible and near-infrared (Vis-NIR) spectroscopy, hyperspectral imaging, Raman spectroscopy, fluorescence spectroscopy, and machine vision, discussing their advantages and disadvantages. In addition, the latest research regarding different detection algorithms and models for the in ovo sexing of chicken embryos was summarized. Therefore, this paper provides updated information regarding the optical sensing techniques that can be used in the poultry industry and related research.

This study aimed to conduct a systematic review to gather evidence to clarify if cheiloscopy can be used in sex estimation and identify the reasons behind the lack of consensus in the scientific community. The systematic review was performed following the PRISMA guidelines. A bibliographic survey was conducted in PubMed, Scopus, and Web of Science databases, restricted to articles published between 2010 and 2020. Studies were selected according to eligibility criteria, and then the study data were collected. The risk of bias in each study was assessed and applied as additional inclusion or exclusion criteria. The results of the articles eligible for analysis were synthesized using a descriptive approach. In the 41 included studies, several methodological flaws and variations between studies that contribute to the discrepancy in results were identified. The data gathered allowed us to conclude that there is no strong scientific evidence to support the use of cheiloscopy in sex estimation, as there is no specific pattern for each sex, which reduces the criminalistic interest of cheiloscopy in estimating this parameter.

The objective of this study is to determine whether the morphometric evaluation of the foramen magnum using computed tomography can be used as an accurate tool in estimating the sex of an individual. An extensive search of the databases, PubMed, ProQuest, Google Scholar, and Scopus, was carried out to procure articles that fulfilled the inclusion criteria. The AQUA tool was used to assess the quality of the included studies. A random effects model was used for the meta-analysis of the eligible studies using the STATA software, version 16, 2019 at 95% CI and p ≤ 0.05. Eleven eligible articles that measured the transverse and sagittal diameters of the foramen magnum using computed tomography were included in this study. The sagittal diameter of the foramen magnum was greater than the transverse diameter, and both the diameters were greater in males than in females. Meta-analysis revealed that both transverse and sagittal diameters were more reliable for male sex estimation. Since there is a dimensional variation between the male and female foramen magnum, it can be used for initial sex identification and also as an auxiliary to other advanced methods of sex estimation.

This systematic review aims to determine whether linear or morphometric analysis of paranasal sinuses can be used for accurate determination of gender and to appraise which sinus can be evaluated for accurate gender determination.A comprehensive search of the specialized databases (PubMed/MEDLINE, Science Direct, Clinical Key, ProQuest, Google Scholar, Epistomonikos, LILACS, OpenGrey) and other institutional repositories was performed for including the studies which assessed paranasal sinuses for gender determination. Quality assessment was carried out with the AQUA tool. The meta-analysis was performed with the eligible study data at 95% CI and p ≤ 0.05 in the random-effects model.Forty-six studies evaluating frontal sinus (13), maxillary sinus (26), frontal and maxillary sinus (5), or three paranasal sinuses (2) were included. All the included studies assessed height, length, width, and volume, respectively, and other additional parameters (area, perimeter) if wherever applicable. Frontal sinus had significantly higher values for males compared to females except for left height (LH) and left volume (LV). Maxillary sinus measurements were significantly higher in males contrasted to females except for LH. Sub-group analyses revealed that analyses involving the population had statistically significant results for all the measured parameters for both the sinuses (p < 0.05 and p = 0.00, respectively).Measurements obtained from assessing sinuses reveal that there are variations in size, among populations in different geographic regions. Hence, more studies with improved sample sizes and standardized measurement protocols should be carried out on different populations to see the diversity and their reliability.

Forensic odontology (FO) mainly deals with the identification of the individual through the remains, which mainly includes teeth and jawbones. Artificial intelligence (AI) technology has proven to be a breakthrough in providing reliable information in decision making in forensic sciences. This systematic review aimed to report on the application and performance of AI technology in FO. The data was gathered through searching for the articles in the renowned search engines, which have been published between January 2000 - June 2020. QUADAS-2 was adopted for the risk of bias analysis of the included studies. AI technology has been widely applied in FO for identifying bite-marks, predicting mandibular morphology, gender determination, and age estimation. Most of these AI models are based on either artificial neural networks (ANNs) or convolutional neural networks (CNNs). The results of the studies are promising. Studies have reported that these models display accuracy and precision equivalent to that of the trained examiners. These models can be promising tools when identifying victims of mass disasters and as an additive aid in medico-legal situations.

Non-invasive prenatal testing (NIPT) can determine the sex of the fetus very accurately and very early in gestation. There are concerns that the ease, timing, and accuracy of NIPT sex determination will facilitate sex-selective termination of pregnancy (TOP). Here, we review current practices, the evidence for a link between NIPT and sex-selective TOP, and associated ethical issues. Sex-selective TOP, usually motivated by son preference, has had serious demographic consequences in countries such as India and China. Currently, ultrasound is the primary method by which parents determine the sex of the fetus. The diffusion of ultrasound technology has had a direct impact on the rates of sex-selective TOP. Although NIPT is currently more costly, it is feasible that increased uptake of this technology could have a similar effect. Partly because NIPT is a relatively recent development in prenatal screening, there is little data on the impact of NIPT on sex selection practices. Evidence that NIPT is playing a role in sex-selective TOP remains largely anecdotal. Further research is required to assess and quantify TOP resulting from NIPT sex determination. The use of these technologies for sex selection raises a number of ethical issues, in addition to practical demographic consequences.

The feasibility of the sterile insect technique (SIT) as a malaria vector control strategy against Anopheles arabiensis has been under investigation over the past decade. One of the critical steps required for the application of this technique to mosquito control is the availability of an efficient and effective sex-separation system. Sex-separation systems eliminate female mosquitoes from the production line prior to irradiation and field release of sterile males. This is necessary because female mosquitoes can transmit pathogens such as malaria and, therefore, their release must be prevented. Sex separation also increases the efficiency of an SIT programme. Various sex-separation strategies have been explored including the exploitation of developmental and behavioural differences between male and female mosquitoes, and genetic approaches. Most of these are however species-specific and are not indicated for the major African malaria vectors such as An. arabiensis. As there is currently no reliable sex-separation method for An. arabiensis, various strategies were explored in an attempt to develop a robust system that can be applied on a mass-rearing scale. The progress and challenges faced during the development of a sexing system for future pilot and/or large-scale SIT release programmes against An. arabiensis are reviewed here. Three methods of sex separation were examined. The first is the use of pupal size for gender prediction. The second is the elimination of blood-feeding adult females through the addition of an endectocide to a blood meal source. The third is the establishment of a genetic sexing strain (GSS) carrying an insecticide resistance selectable marker (dieldrin-resistance rdl gene and/or other GABA receptor antagonists that can be used as alternative insecticides to dieldrin) or a temperature-sensitive lethal marker.

Sex estimation is considered as one of the essential parameters in forensic anthropology casework, and requires foremost consideration in the examination of skeletal remains. Forensic anthropologists frequently employ morphologic and metric methods for sex estimation of human remains. These methods are still very imperative in identification process in spite of the advent and accomplishment of molecular techniques. A constant boost in the use of imaging techniques in forensic anthropology research has facilitated to derive as well as revise the available population data. These methods however, are less reliable owing to high variance and indistinct landmark details. The present review discusses the reliability and reproducibility of various analytical approaches; morphological, metric, molecular and radiographic methods in sex estimation of skeletal remains. Numerous studies have shown a higher reliability and reproducibility of measurements taken directly on the bones and hence, such direct methods of sex estimation are considered to be more reliable than the other methods. Geometric morphometric (GM) method and Diagnose Sexuelle Probabiliste (DSP) method are emerging as valid methods and widely used techniques in forensic anthropology in terms of accuracy and reliability. Besides, the newer 3D methods are shown to exhibit specific sexual dimorphism patterns not readily revealed by traditional methods. Development of newer and better methodologies for sex estimation as well as re-evaluation of the existing ones will continue in the endeavour of forensic researchers for more accurate results.

OBJECTIVE: To evaluate the success rate and reliability of fetal sex determination in first trimester between 11-13+ 6 weeks and make a comparative study with other studies.
METHODS: A cohort study was performed. 2314 first trimester pregnancy ultrasounds were examined. For fetal sex estimation, the method of a sagittal section and the relation between the angle formed by the genital tubercle and spinal column was used.
RESULTS: Diagnosis of fetal sex was issued in 1986 cases with 90.1% success rate. In 328 cases (14.2%) no gender assignment was achieved. A directly proportional relationship between success rate in fetal sex diagnosis and crown-rump length (CRL) (p < 0.001) was described; with CRL over 65 mm, the prediction of fetal sex is above 95% and from 77 mm is close to 100%. With CRL < 51 mm, the success rate is less than 80% in both sexes.
CONCLUSIONS: The simplest and best performing technique is the relation between the angle formed by the genital tubercle and spinal column. Success rate below 60 mm is less than 90% overall, so it would have to be wary of establishing the fetal sex, especially if it involves a decision as to avoid an invasive test.

BACKGROUND: Discovery of cell-free fetal DNA (cffDNA) in maternal blood in 1997 by Lo et al. has opened the possibility of a noninvasive prenatal test (NIPT). Currently, it is employed in the analysis of aneuploidies and fetal sex determination. Massive parallel sequencing (MPS) detects the origin of each amplified sequence, and analyses over-representation of sequences or any decrease in the fetal chromosomes in maternal plasma. This technique has been validated and allows assessment of trisomies 13, 18 and 21, obtaining the result in about a week from 10-weeks of gestational age. By using NIPT, we expect a reduction in the number of invasive studies and the risk of fetal loss.
OBJECTIVE: To communicate the experience obtained at Genetics Clinic of the Hospital Angeles Lomas, in the use of NIPT by MPS as a method of prenatal screening for aneuploidies and fetal sex determination.
METHODS: A prospective, observational and descriptive study was carried out in order to develop a database of patients who underwent NIPT (Harmony test) from August 2013 to date. Maternal blood samples were analyzed at Ariosa Diagnostics Inc. at San Jose California, USA.
RESULTS: Noninvasive prenatal test was applied to 42 patients, with average maternal age of 37.1 years. The percentage of gestational age was 13.3 weeks and of fetal fraction was 12.7%. Two cases of high risk of trisomy 18 and two cases with high risk for X monosomy were obtained. In only one case the test was used for fetal determination, because of a story of Wiskott-Aldrich (W-A) disease. In all cases of low risk, the result was confirmed at birth and fetal sex was consistent with reports of literature.
CONCLUSIONS: NIPT is currently the screening test with the highest detection rate (greater than 98%, with a false negative rate lesser than 0.5% and a sensitivity and specificity close to 100%), although it can vary from one chromosome to another. It is indicated for women with a result of high risk for trisomy 13, 18 and 21. This test has not been validated for low risk women or multiple pregnancies. In our series, the most frequent indication was advanced maternal age. The weight of the patients is important because it is a factor related to the percentage of fetal DNA. In cases with high risk for X monosomy in which the cytogenetic result was 46, XX, it is important to consider as much causes as possible, such as uniparental disomy (UPD), mosaicism and maternal contamination. Only in a case with W-A story the test was conducted specifically for fetal sex determination and confirmed by amniocentesis. In the cases of high-risk results, confirmation by an invasive method, before an obstetric decision, is indispensable. Further studies are still needed to continue the validation of this test by different molecular techniques and in other groups of patients.