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We report that dissociative electron attachment (DEA) to HCl is strongly enhanced by adsorption on the surface of H[sub 2]O ice. The absolute DEA cross section at ∼0 eV for HCl adsorbed on ice is measured to be ∼4.0×10[sup -15] cm[sup 2], which is two orders of magnitude higher than in the gas phase. This enhancement is essentially due to electron transfer from precursor states of the solvated electron in ice to an unfilled molecular orbital of HCl followed by its dissociation. This study indicates that electron-induced dissociation may be a significant process leading to HCl dissociation on ice surfaces in polar stratospheric clouds due to ionization by cosmic rays. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report measurements of electron stimulated desorption yields and kinetic energy distributions for F[sup -] and Cl[sup -] anions from thin films of CF[sub 2]Cl[sub 2] condensed on polycrystalline platinum at 20 K. Dissociative electron attachment processes cause a peak in the F[sup -] yield at an electron energy of ∼4 eV and a peak in the Cl[sup -] yield at ∼7 eV. After electron irradiation, a new dominant structure appears in the Cl[sup -] yield at 5 eV incident electron energy, and Cl[sup -] ions having high kinetic energy (>1 eV) are observed in the kinetic energy distributions. These changes are attributed to the synthesis of Cl[sub 2] in the condensed phase induced by electron irradiation of the CF[sub 2]Cl[sub 2] film. This Cl[sub 2] formation is demonstrated by the observation in the Cl[sup -] yield of the Cl[sub 2][sup -]/Cl[sub 2] [sup 2]Π[sub u] resonance state, and by Cl[sup -] kinetic energy distributions that are similar to those obtained from condensed pure Cl[sub 2] films. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Animal models of traumatic brain injury (TBI) are essential for testing novel hypotheses and therapeutic interventions. Unfortunately, due to the broad heterogeneity of TBI in humans, no single model has been able to reproduce the entire spectrum of these injuries. The controlled cortical impact (CCI) model is one of the most commonly used models of contusion TBI. However, behavioral evaluations have revealed transient impairment in motor function after CCI in rats and mice. Here we report a new semicircular CCI (S-CCI) model by increasing the impact tip area to cover both the motor cortex and hippocampal regions in adult mice. Mice were subjected to S-CCI or CCI using an electromagnetic impactor (Impactor One(TM), MyNeuroLab; semicircular tip: 3mm radius; CCI tip diameter: 3mm). We showed that S-CCI, at two injury severities, significantly decreased the neuroscore and produced deficits in performance on a rotarod device for the entire duration of the study. In contrast, the CCI induced motor deficits only at early stages after the injury, suggesting that the S-CCI model produces long-lasting motor deficits. Morris water maze test showed that both CCI and S-CCI produced persisting memory deficits. Furthermore, adhesive removal test showed significant somatosensory and motor deficits only in the S-CCI groups. Histological analysis showed a large extent of cortical contusion lesions, including both the sensory and motor cortex, and hippocampal damage in the S-CCI. These findings collectively suggest that the current model may offer sensitive, reliable, and clinically relevant outcomes for assessments of therapeutic strategies for TBI. [ABSTRACT FROM AUTHOR]

The tetanus has been eliminated in the pregnancy women and newborns in China. However, there is a gap for adult tetanus immunization, and the risk of tetanus infection cannot be ignored. In order to clearly understand the effect of the tetanus to human beings and the current use of tetanus immunological preparation for adult post-exposure prophylaxis, the incidence of the tetanus, the use status of tetanus immunological preparation and recommendations for post-exposure prophylaxis at home and abroad were reviewed and summarized, which may provide academic evidence for post-exposure prophylaxis procedures and use of tetanus immunological preparation.

With characteristics of high infectivity, diverse transmission routes and high variation, norovirus is the main pathogen of sporadic cases and outbreaks of acute gastroenteritis, resulting in a serious disease burden. This paper summarizes the latest progress in epidemiological research of norovirus infection from aspects of disease burden caused by acute gastroenteritis, virus variation and predominant strains, prevention and control measures, and immunization and vaccine development.

Objective: To investigate the incidence and determinants of vaccine hesitancy towards national immunization program in China and understand the current status of parents' hesitancy to different vaccines used in national immunization program. Methods: A cross-sectional survey was conducted in Beijing, Sichuan and Gansu. The methods of proportional probability sampling and convenience sampling were used to select the eligible study subjects for questionnaire surveys. Results: A total of 3 592 parents were enrolled in the study, in whom 38.22% fully accepted all the vaccines, 59.35% agreed to let their children to receive all the vaccines but showed slight concern, and 2.42% had hesitancy to the vaccines. The vaccine with the most hesitancy was polio vaccine (0.89%), followed by diphtheria pertussis tetanus vaccine (0.70%) and hepatitis A vaccine (0.64%). The dominant reason for vaccine hesitancy was the risk-benefit perception of vaccination (31.03%), followed by the low awareness of the parents (21.84%) and the inconvenience caused by distance and time (21.84%). Conclusions: The incidence of vaccine hesitancy towards national immunization program was low in parents in China, but over 50% of the parents showed concern to the vaccines. It is essential to improve the service quality of national immunization program and strengthen the health education about the vaccination to reduce the incidence of vaccine hesitancy in parents.

Human challenge trial (HCT) is a test in which human volunteers are intentionally infected with pathogens in order to evaluate the efficacy of candidate preventive or therapeutic drugs. During the COVID-19 pandemic, the HCT of vaccines has aroused people's attention due to its significant advantages over clinical trial. This paper introduces the concept, development and application of HCT, the advantages and limitations of HCT for vaccine evaluation, and the consideration of future HCT of COVID-19 vaccine in China.

The article "Lewy pathological study on α-synuclein in gastrointestinal tissues of prodromal Parkinson's disease" by Q.-B. Lu, Z.-F. Zhu, H.-P. Zhang, W.-F. Luo, published in Eur Rev Med Pharmacol Sci 2017; 21 (7): 1514-1521 has been withdrawn.

Objective: To understand the distribution of the severe fever with thrombocytopenia syndrome (SFTS) in Zhejiang province, and predict the incidence and the probability of SFTS outbreak. Methods: Based on the cases of SFTS from 2011-2015, software ArcGIS 10.0 was used to analyze the spatial distribution, Moran's I and Getis-Ord Gi were used to analyze the spatial autocorrelation. The incidence trend was explored by trend surface analysis, and the prediction was made by Kriging interpolation. Results: The incidence of SFTS increased and the distribution expanded in Zhejiang from 2011 to 2015, the seasonal and the demographic characteristics of SFTS were similar to the previous research; there were regional clustering of the cases ( P <0.001); a downward trend was observed from northeast to southwest in terms of incidence of SFTS; the second-order disjunctive Kriging interpolation based on circular model and the indicator Kriging interpolation based on exponential model had higher prediction accuracy, the probabilities of outbreak in Anji, Daishan and Tiantai were high, the prediction deviation of inland was less than that of edge area. Conclusion: The prediction of SFTS by Kriging interpolation had high accuracy, the incidence of SFTS was higher and the distribution of SFTS was larger than the results of surveillance, the risk areas for epidemic were Anji, Daishan, Ninghai,Tiantai, Sanmen and Linhai.

Combination of low-dose cisplatin with radiotherapy or photodynamic therapy (PDT) is a novel cancer treatment. Using time-resolved femtosecond laser spectroscopy, we reveal the molecular mechanisms of the combinations of cisplatin with radiotherapy and PDT using indocyanine green (ICG) excited at 800 nm. DNA damage measurements confirm that electron-transfer reactions of cisplatin with electrons generated in ionizing radiation and with the ICG singlet excited state in PDT are responsible for the cytotoxic enhancements.

We present measurements on the trapping of 0-3 eV electrons in H2O ice films covered with a submonolayer of N2 molecules. At the energy of the N-2((2)Pi(g)) shape resonance, the absolute cross section for electron trapping in ice is approximately 5.5 x 10(-16) cm(2), similar to that for vibrational excitations of gaseous N2 via the resonance. This result, indicating that nearly all electrons from autoionization of N-2((2)Pi(g)) are transferred to electron traps in ice, is explained by superinelastic electron transfer from N-2((2)Pi(g)) into preexisting traps in polar ice, leaving N2 in high vibrational excited states.

It was found by the observations of clinical treatment that the three indexes of epinephrine(E), norepinephrine(NE) and dopamine(D) of urinary catecholamine(CA) increased (P less than 0.001, P less than 0.05 and P less than 0.001) for the climacteric patients who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat of the heart, and the urinary 17-hydroxycorticosteroid (17-OHCS) increased (P less than 0.001) for the patients who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat of the liver. Both the three indexes and urinary 17-OHCS increased for the two groups (P less than 0.01). However, for all the above groups who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat, the NE/E ratio was larger than the normal ratio, which stands for the level of central catecholamine. After the treatment with new Gengnian prescriptions, the clinical symptoms of the patients were improved, and in the meantime urinary CA. 17-OHCS and NE/E were decreased. The total efficiency was 89.2%. The principle of treatment with this prescription may be due to the fact that the level of central catecholamine decreased so that the excessive excitation of sympathetics-adrenocortical system and sympathetics-adrenocortical system was restrained.