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High-Resolution Infrared-Vacuum Ultraviolet Photoion and Pulsed Field Ionization-Photoelectron Methods for Spectroscopic Studies of Neutrals and Cations

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Chinese Journal of Chemical Physics 2008年第3期21卷 193-201页

作者： Xi Xing beth reed Mi Kyung Bahng Peng Wang Hin Koo Woo Sun Jong Baek Chee Shing Lain Cheuk Yiu Ng Department of Chemistry University of California Davis Davis California 95616 USA

We show that by scanning the frequency of a single mode infrared （IR） optical parametric oscillator （IR- OPO） laser to excite the molecular species of interest and fixing the frequency of a vacuum ultraviolet （VUV） laser to photoionize the IR excited species, high-resolution IR spectra of polyatomic neutrals can be obtained with high sensitivity. The fact that this IR-VUV-photoion （IR-VUV-PI） method is based on VUV photoionization probe, and thus, allows the identification of the neutral IR absorber, makes it applicable for IR spectroscopy measurements of isotopemers, radicals, and clusters, which usually exist as impure samples. The highly resolved IR-VUV-PI measurements achieved using the single mode IR-OPO laser have made possible the selection of single rovibrational states of CH3X （X=Br and I）, C2H4, and C3H4 for VUV-pulsed field ionization-photoelectron （VUV-PFI-PE） measurements, resulting in rovibrationally resolved photoelectron spectra for these polyatomic molecules. These experiments show that the signal- to-noise ratios of the IR-VUV-PI and IR-VUV-PFI-PE spectra obtained by employing the high-resolution IR-OPO laser are significantly higher than those observed in previous IR-VUV-PI and IR-VUV-PFI-PE studies using a low-resolution IR-OPO laser. Further improvement in sensitivity of IR-VUV-PI and IR- VUV-PFI-PE measurements by using the collinear arrangement of IR-VUV lasers and molecular beam is discussed.

关键词： Vacuum ultraviolet Infrared Pulse-field photoelectron High resolution

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Broken connections of wetland cultural knowledge

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Ecosystem Health and Sustainability 2016年第7期2卷 1-3页

作者： beth A.Middleton U.S.Geological Survey Wetland and Aquatic Research Center700 Cajundome BoulevardLafayetteLouisiana 70506 USA

As global agriculture intensifies,cultural knowledge of wetland utilization has eroded as natural resources become more stressed,and marginal farmers move away from the *** excellent paper by Fawzi et al.(2016)documents a particularly poignant case of traditional knowledge loss among the Marsh Arab women of *** interviews,the authors document the breakdown of skill transfer from the older to younger generation of *** authors link the loss of their cultural knowledge with the loss of wetlands in the *** can no longer provide support for their families using wetland products,and along with that,their ancient knowledge of plant usage is *** ancient skills included medicinal uses,and reed harvesting for both weaving and water buffalo ***,the majority of the Mesopotamian Marshes have dried,this way of life is being forgotten(Fawzi et al.2016).The global tragedy is that while the careful alliance of wetlands and people have sustained human cultures for millennia,degraded wetlands lose their ability to provide these services(Maltby 1986).

关键词： younger sustained wetland

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Vitamin D Deficiency and Insufficiency in Northeast Tennessee

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Health 2020年第9期12卷 1085-1094页

作者： Arun Joseph Kattakayam Donovan reed Sajin M. Karakattu beth Bailey Millard Ray Lamb Paul O. Lewis Dima Youssef Department of Internal Medicine Norwalk Hospital Norwalk CT USA Texas Oculoplastics Consultants TOC Eye & Face Austin TX USA Department of Internal Medicine Division of Pulmonary and Critical Care East Tennessee State University Johnson City TN USA Department of Family Medicine East Tennessee State University Johnson City TN USA Recovery Associates Johnson City TN USA Department of Pharmacy Johnson City Medical Center Johnson City TN USA Department of Internal Medicine Division of Infectious Diseases East Tennessee State University Johnson City TN USA

Background: The role of vitamin D in population subgroups throughout the world continues to be a topic of interest among researchers. Current evidence demonstrates that treating vitamin D deficiency plays a significant role in improving mortality in hospitalized patients, reducing hospital length of stay, and boosting innate immune system. Vitamin D levels vary with age, gender, body mass index (BMI) and geographical area. The purpose of this study is to evaluate vitamin D levels in a cohort of patients in Northeast Tennessee. Study: This institutional review board-approved, retrospective study evaluated vitamin D levels of patients obtained from Mcleod Cancer and Blood Center. Vitamin D levels were collected over a 2-year period and classified as deficient (30 ng/mL). Data were then stratified based on patient characteristics (age, gender, body mass index (BMI), race, seasons, and place of residence) and compounds of vitamin D (D2 and D3). Results: There were 2011 individuals included, with only 44.3% having replete levels and 21.4% with levels less than 20 ng/mL. Females with vitamin D deficiency are more likely to have levels below 20 ng/ml compared to males (18.6% vs. 23%, respectively, p = 0.003). Regarding BMI, the highest levels were reported in normal weight and overweight. With regards to age, advanced age (≥70) was associated with the highest levels and most replete patients. Winter months were associated with the lowest levels of vitamin D. Higher vitamin D levels were found in individuals over 70 years, normal weight and overweight category. Conclusion: Testing vitamin D levels in high-risk groups becomes of utmost importance in areas with longer winter months, obese and underweight patients. Vitamin D levels should be routinely tested and treated in vulnerable populations.

关键词： Vitamin D Vitamin D Deficiency Vitamin D Insufficiency Northeast Tennessee

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Vitamin D Deficiency and Insufficiency in Northeast Tennessee

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Health 2020年第9期

作者： Arun Joseph Kattakayam Donovan reed Sajin M. Karakattu beth Bailey Millard Ray Lamb Paul O. Lewis Dima Youssef

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