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In many countries, especially developed nations, the fertility rate and birth rate have continually declined. Taiwan’s fertility rate has paralleled this trend and reached its nadir in 2022. Therefore, the government uses many strategies to encourage more married couples to have children. However, couples marrying at an older age may have declining physical status, as well as hypertension and other metabolic syndrome symptoms, in addition to possibly being overweight, which have been the focus of the studies for their influences on male and female gamete quality. Many previous studies based on infertile people are not truly representative of the general population. This study proposed a framework using five machine learning (ML) predictive algorithms—random forest, stochastic gradient boosting, least absolute shrinkage and selection operator regression, ridge regression, and extreme gradient boosting—to identify the major risk factors affecting male sperm count based on a major health screening database in Taiwan. Unlike traditional multiple linear regression, ML algorithms do not need statistical assumptions and can capture non-linear relationships or complex interactions between dependent and independent variables to generate promising performance. We analyzed annual health screening data of 1375 males from 2010 to 2017, including data on health screening indicators, sourced from the MJ Group, a major health screening center in Taiwan. The symmetric mean absolute percentage error, relative absolute error, root relative squared error, and root mean squared error were used as performance evaluation metrics. Our results show that sleep time (ST), alpha-fetoprotein (AFP), body fat (BF), systolic blood pressure (SBP), and blood urea nitrogen (BUN) are the top five risk factors associated with sperm count. ST is a known risk factor influencing reproductive hormone balance, which can affect spermatogenesis and final sperm count. BF and SBP are risk factors associated with metabolic syndrome, another known risk factor of altered male reproductive hormone systems. However, AFP has not been the focus of previous studies on male fertility or semen quality. BUN, the index for kidney function, is also identified as a risk factor by our established ML model. Our results support previous findings that metabolic syndrome has negative impacts on sperm count and semen quality. Sleep duration also has an impact on sperm generation in the testes. AFP and BUN are two novel risk factors linked to sperm counts. These findings could help healthcare personnel and law makers create strategies for creating environments to increase the country’s fertility rate. This study should also be of value to follow-up research.

A novel in situ chemical precipitation method to directly synthesize CdS nanocrystal arrays in the presence of microporous templates of poly(glycidyl methacrylate-grafted-3,3′-dimethyl-(4-hydroxyphenylazanediyl) bis(2-methylpropanoate))-random-polystyrene (PGHS), which were formed by self-assembling dendritic-linear PGHS copolymers via the solvent-induced phase separation process, were investigated. The surface morphology of the PGHS template and the spatial positions of the CdS nanocrystals in the PGH-CdS could be easily and quickly controlled by altering the content of the dendritic GMA-HPAM segments. The diameters of the CdS nanocrystals on the PGHS-CdS template were uniform in the range of 3–4 nm. Large-area, hexagonally ordered CdS nanocrystal-array domains were discovered in the PGHS2-CdS template used in this study.

A series of dendritic-linear copolymers, composed of poly(glycidyl methacrylate-grafted- 3,3′-dimethyl-(4-hydroxyphenylazanediyl) bis(2-methylpropanoate))-random-polystyrene (PGMA-HPAM-r-PS), were successfully synthesized via a macromonomer route. Characterization of the copolymers and investigation of their thermal behavior revealed a significant influence of the dendritic GMA-HPAM segment. The thermal degradation temperature (Td) of the dendritic-linear PGMA-HPAM-r-PS copolymer was elevated as the weight percentage of dendritic segment (GMA-HPAM) increased. The glass transition temperatures of the copolymers exhibited a strong, complex dependence on the dendritic GMA-HPAM segment, with three behavioral ranges. DSC data were attributed to two distinct effects of the dendritic segment: (i) the effect of the dendritic segment grafting on copolymer chains, and (ii) intermolecular interactions between the dendritic and styrene segments. Microporous dendritic-linear PGMA-HPAM-r-PS copolymer matrices were prepared using solvent-induced phase separation at room temperature. The self-assembled surface morphology was affected by (i) the micellar domains of the dendritic and styrene segments and (ii) inter- and intramolecular interactions between the dendritic and styrene segments. An interesting relationship between thermal behavior and surface morphology was discovered, which can provide a simple, accurate and rapid means of finding the optimum dendritic segment content for producing a hexagonally ordered microporous matrix for different dendron generations.

A set of dendritic−linear copolymers, poly(glycidyl methacrylate-grafted-dimethyl 3,3′-(4-hydroxyphenylazanediyl)bis(2-methylpropanoate))-random-polystyrene (PGMA-HPAM-r-PS), were successfully prep...

The chemically covalent polyethylenimine–siloxane hybrids doped with various amounts of ortho-phosphoric acid (H3PO4) were prepared and characterized by FTIR, DSC, TGA, and solid-state NMR spectra. The protonic conduction behavior of these materials was also investigated by means of impedance measurements. These observations indicate that the hydrogen bonding and protonic interactions exist between the dopant H3PO4 and the hybrid host, resulting in an increase in Tg of polyethylenimine segments. These hybrids are thermally stable up to 200 °C from TGA analysis. Conductivity studies show an Arrhenius behavior characteristic and the Grotthus-like proton conduction, and a high conductivity of 10−2–10−3 S cm−1 at 110 °C in dry atmosphere for the hybrid membrane with H3PO4/EI of 0.5. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2135–2144, 2006