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Background Caesarean section rates are rising worldwide. One adverse effect of caesarean section reported in some studies is an increased risk of subfertility. Only a few studies have assessed the relationship between the previous mode of delivery and in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) reproductive outcomes. In this study, we primarily investigated the impact of a history of caesarean section with or without defects on IVF/ICSI-ET outcomes compared to a vaginal delivery history. Methods This retrospective study included 834 women who had a IVF or ICSI treatment at our centre between 2015 and 2019 with a delivery history. In total, 401 women with a previous vaginal delivery (VD) were assigned to the VD group, and 433 women with a history of delivery by caesarean section were included, among whom 359 had a caesarean scar (CS) without a defect and were assigned to the CS group and 74 had a caesarean section defect (CSD) and were assigned to the CSD group. Baseline characteristics of the three groups were compared and analysed. Binary logistic regression analyses were performed to explore the association between clinical outcomes and different delivery modes. Results There were no significant differences in the live birth rate, biochemical pregnancy rate, clinical pregnancy rate, mean implantation rate or abnormal pregnancy rate between the CS and VD groups However, the live birth rate and mean implantation rate in the CSD group were significantly lower than those in the VD group (21.6 vs 36.4%, adjusted OR 0.50 [0.27–0.9]; 0.25 ± 0.39 vs 0.35 ± 0.41, adjusted OR 0.90 [0.81–0.99]). Among women aged ≤ 35 years, the subgroup analyses showed that the live birth rate, biochemical pregnancy rate, clinical pregnancy rate, and mean implantation rate in the CSD group were all significantly lower than those in the VD group (21.4 vs 45.8%, adjusted OR 0.35[0.15 ~ 0.85]; 38.1 vs 59.8%, adjusted OR 0.52[0.24–0.82]; 31.0 vs 55.6%, adjusted OR 0.43[0.19–0.92]; 0.27 ± 0.43 vs 0.43 ± 0.43, adjusted OR 0.85[0.43 ± 0.43]). For women older than 35 years, there was no statistically significant difference in any pregnancy outcome among the three groups. Conclusions This study suggested that the existence of a CS without a defect does not decrease the live birth rate after IVF or ICSI compared with a previous VD. However, the presence of a CSD in women, especially young women (age ≤ 35 years), significantly impaired the chances of subsequent pregnancy.

Global decline in male fertility and their associations with ubiquitous exposure of phthalates (PAEs) have raised public concerns. However, the current epidemiological data are limited and controversial. Hence, we investigated possible associations between PAE exposure and male infertility. Eleven phthalate metabolites (mPAEs) were determined in urine and serum samples collected from eighty-eight males diagnosed with infertility from Tianjin, China. The median serum levels of mPAE were n.d. −3.63 ng/mL, which were 1–2 orders of magnitude lower than the urinary levels of n.d. −192 ng/mL. Negative associations were identified between urinary follicle-stimulating hormone (FSH) and MiBP and serum MCMHP, as well as testosterone (T) and luteinizing hormone (LH) and the molar concentrations of ∑mPAE, while positive association was found between T and the serum molar concentrations of ∑mDEHP. Positive associations were found between the molar concentrations of serum ∑mPAE and sperm concentration, sperm motility rate, and progressive motility, between mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) and semen volume and total sperm number, and between MCMHP and progressive motility, while negative association was found between mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) and progressive motility. Moreover, FSH was found to mediate the association between serum concentrations of MCMHP and progressive motility (mediation ratio = 41.6%), and LH to mediate the associations between serum concentrations of ∑mPAE and sperm concentration (mediation ratio = 45.7%) and sperm motility rate (mediation ratio = 29.0%). These results also suggested that serum levels of mPAE are a good predictor for male infertility. Further efforts need to be made on toxicological studies to systematically elaborate the internal mechanisms.

This retrospective cohort study aimed to analyse the risk of congenital anomalies (CAs) in infants conceived by infertile women through assisted reproductive technology (ART). A total of 9,013 clinical pregnancy cycles resulting in 9,101 live births between 2004 and 2014 were analysed. Congenital anomalies were evaluated and compared with spontaneous pregnancies in infertile women. A total of 9,101 infants were born following ART. Three subgroups were established: In vitro fertilisation fresh embryo transfer (IVF-ET), n=2,919, intracytoplasmic sperm injection fresh embryo transfer (ICSI), n=1,996 and frozen-thawed embryo transfer (FET), n=4,186. No significant differences in perinatal outcomes were observed between the three subgroups. A total of 105 (1.15%) infants were born with CAs. The birth defect rate was slightly higher in the IVF-ET subgroup compared with the other subgroups. Among infants in the IVF-ET and ICSI-ET subgroup, the probability of birth defects increased with increased maternal age (>35 years), male factors and diminished ovarian reserve. In the FET group, the risk of birth defects was significantly increased with multiple births and maternal age >35 years. The risk of congenital anomalies following ART was not significantly different compared with spontaneous conceptions within the infertile study population. The results of the present study may provide guidance for patients who are considering treatment for infertility in China.

This paper presents a three-dimensional (3D) digital watermarking technique based on integral image cryptosystem and discrete Fresnel diffraction (DFD). 3D digital watermarking is generated by computational integral imaging. The 3D digital watermarking is encrypted and embedded by integral imaging cryptosystem that is designed with DFD transform algorithm. Finally, the extracted 3D digital watermarking is decrypted and displayed by integral imaging cryptosystem. The feasibility and effectiveness of the proposed scheme is demonstrated by numerical simulation experiment. The majority of system will improve the security and robustness of 3D digital watermarking. The proposed method can provide a new, real-time, and effective strategy in the security data management of cloud computing and big data.

Based upon the command and control network infrastructure of the Army, now electronic military systems are being built to store, transfer, query and manipulate data for various military tasks. However, in the open and interconnected network environment, military systems are facing two main typical security threats, i.e., broken authentication and broken access control. This paper proposes an idea of building a security Web-based electronic military system by utilizing network security trust units. An authorization component based on PKI (Public Key Infrastructure) and LDAP (Lightweight Directory Access Protocol), as well as an access control component based on T-RBAC (Task-Role Based Access Control) are designed. The implemented security components are embedded into an online manuscript submission and editing system for CAPF (Chinese Armed Police Force) newspaper office to ensure data and workflow security. Practical application shows the implemented security components can effectively guarantee the security and reliability of the system.

Efficient identity based signature/signcryption in the standard model with full security has been pursued for a long time. At ISDPE'07, Ren and Gu claimed to construct efficient identity based signature/signcryption schemes with full security in the standard model. They claimed their schemes have short public parameters, high efficiency and a tight reduction. But in this paper we give attacks to their schemes to show their schemes are not secure.

Hierarchical identity based signature generalizes the concept of identity based signature to organization hierarchy. Till now, there are many interesting hierarchical identity based signature schemes. At ChinaCrypt'08, Ren and Gu claimed to construct an efficient hierarchical identity based signature scheme based on the q-SDH problem with full security in the standard model. They claimed their scheme has short public parameters, high efficiency and a tight reduction. But in this paper we give an attack to their scheme to show their scheme is not secure.

With development of grid technology, sensitive data protection becomes a difficult task for accesses from heterogeneous domains. Moreover, anonymity and unknown peers worsen security problems. Traditional access control mechanisms are not suitable to distributed environment. Several models and mechanisms make use of trust evaluation to assist access control decision. But few explicitly consider trust and risk as two separate factors which affect interactions between peers. In this paper, we present an access control mechanism which considers both trust and risk as two vital parameters. We also introduce static game model with incomplete information to analyze the optimal decision. In addition, a new model of trust evaluation is proposed to represent the confidence in the peer. To appease people’s anxiety about loss, a model of risk assessment is also presented to indicate impacts on resources. At the end of this paper, to describe how our mechanism works, a scenario is provided.

With the development of grid technology, sensitive files and data protection become difficult tasks multi-domains. Traditional access control mechanisms are not suitable to such distributed environment. Several models and mechanisms utilize trust to assist access control decision. But few explicitly consider trust and risk as two separate factors which affect interactions between peers. In this paper, we present a novel mechanism which considers both trust and risk as two vital parameters to assist access control decision. In addition, a novel model of trust evaluation is proposed to represent the confidence in the peer. And to appease peoplepsilas anxiety about loss, a new model of risk assessment is also presented to indicate impacts on resources. At the end of this paper, simulation results will indicate that our mechanism is able to secure local system more efficiently and reliably.

Till now, there are not many ways to construct signature schemes in the standard model and recently many researchers show great interest in construction secure signatures in the standard model. CCA secure publicly verifiable public key encryption in the standard model PVPKE is a new interesting primitive, in which the ciphertext's validity/integrity can be publicly verified. In this paper, we propose a new way to construct signature schemes in the standard model. That is, transforming CCA secure publicly verifiable public key encryption schemes into signature schemes. Our transformation based on the following facts: 1 the signature scheme and CCA secure publicly verifiable public key encryption scheme share the same 'publicly verifiability' property; 2 the signature scheme requires the signatures can not be malleable, and CCA secure publicly verifiable public key encryption also require the ciphertexts can not be malleable; 3 public key encryption and digital signature schemes can be viewed as dual of each other. By utilising these facts, we try to give a new way to construct signature scheme in the standard model.