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1. A Review of NEST Models, and Their Application to Improvement of Particle Identification in Liquid Xenon Experiments

Author

Szydagis, M., Balajthy, J., Block, G. A., Brodsky, J. P., Brown, E., Cutter, J. E., Farrell, S. J., Huang, J., Kozlova, E. S., Liebenthal, C. S., McKinsey, D. N., McMichael, K., Mooney, M., Mueller, J., Ni, K., Rischbieter, G. R. C., Tripathi, M., Tunnell, C. D., Velan, V., Wyman, M. D., Zhao, Z., and Zhong, M.

Subjects
High Energy Physics - Experiment, Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

This paper discusses microphysical simulation of interactions in liquid xenon, the active detector medium in many leading rare-event physics searches, and describes experimental observables useful to understanding detector performance. The scintillation and ionization yield distributions for signal and background are presented using the Noble Element Simulation Technique, or NEST, which is a toolkit based upon experimental data and simple, empirical formulae. NEST models of light and of charge production as a function of particle type, energy, and electric field are reviewed, as well as of energy resolution and final pulse areas. After vetting of NEST against raw data, with several specific examples pulled from XENON, ZEPLIN, LUX / LZ, and PandaX, we interpolate and extrapolate its models to draw new conclusions on the properties of future detectors (e.g., XLZD), in terms of the best possible discrimination of electronic recoil backgrounds from the potential nuclear recoil signal due to WIMP dark matter. We find that the oft-quoted value of a 99.5% discrimination is likely too conservative. NEST shows that another order of magnitude improvement (99.95% discrimination) may be achievable with a high photon detection efficiency (g1 about 15-20%) and reasonably achievable drift field of approximately 300 V/cm., Comment: 26 Pages, 6 Tables, 15 Figures, 18 Equations, and 156 References

Published
2022

2. A Review of Basic Energy Reconstruction Techniques in Liquid Xenon and Argon Detectors for Dark Matter and Neutrino Physics Using NEST

Author

Szydagis, M., Block, G. A., Farquhar, C., Flesher, A. J., Kozlova, E. S., Levy, C., Mangus, E. A., Mooney, M., Mueller, J., Rischbieter, G. R. C., and Schwartz, A. K.

Subjects
High Energy Physics - Experiment, Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment
Abstract

Detectors based upon the noble elements, especially liquid xenon as well as liquid argon, as both single- and dual-phase types, require reconstruction of the energies of interacting particles, both in the field of direct detection of dark matter (Weakly Interacting Massive Particles or WIMPs, axions, etc.) and in neutrino physics. Experimentalists, as well as theorists who reanalyze/reinterpret experimental data, have used a few different techniques over the past few decades. In this paper, we review techniques based on solely the primary scintillation channel, the ionization or secondary channel available at non-zero drift electric fields, and combined techniques that include a simple linear combination and weighted averages, with a brief discussion of the applications of profile likelihood, maximum likelihood, and machine learning. Comparing results for electron recoils (beta and gamma interactions) and nuclear recoils (primarily from neutrons) from the Noble Element Simulation Technique (NEST) simulation to available data, we confirm that combining all available information generates higher-precision means, lower widths (energy resolution), and more symmetric shapes (approximately Gaussian) especially at keV-scale energies, with the symmetry even greater when thresholding is addressed. Near thresholds, bias from upward fluctuations matters. For MeV-GeV scales, if only one channel is utilized, an ionization-only-based energy scale outperforms scintillation; channel combination remains beneficial. We discuss here what major collaborations use., Comment: 42 Pages, 2 Tables, 11 Figures, 13 Equations

Published
2021
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4. Improving diet, activity and wellness in adults at risk of diabetes: randomized controlled trial.

Author

Block, G, Azar, KMJ, Romanelli, RJ, Block, TJ, Palaniappan, LP, Dolginsky, M, and Block, CH

Subjects
Humans, Fruit, Vegetables, Diabetes Mellitus, Prediabetic State, Obesity, Weight Loss, Dietary Carbohydrates, Blood Glucose, Dietary Fats, Body Mass Index, Exercise, Feeding Behavior, Health Behavior, Nutrition Policy, Middle Aged, Health Promotion, Female, Male, Overweight, Surveys and Questionnaires, Diet, Healthy, Healthy Diet, Diet, Healthy, Clinical Sciences, Nutrition and Dietetics, Anthropology
Abstract

ObjectiveThe purpose of this analysis is to examine the effect of an algorithm-driven online diabetes prevention program on changes in eating habits, physical activity and wellness/productivity factors.MethodsThe intervention, Alive-PD, used small-step individually tailored goal setting and other features to promote changes in diet and physical activity. A 6-month randomized controlled trial was conducted among patients from a healthcare delivery system who had confirmed prediabetes (n =339). Change in weight and glycemic markers were measured in the clinic. Changes in physical activity, diet and wellness/productivity factors were self-reported. Mean age was 55 (s.d. 8.9) years, mean body mass index was 31 (s.d. 4.4) kg m(-2), 68% were white and 69% were male.ResultsThe intervention group increased fruit/vegetable consumption by 3.71 (95% confidence interval (CI) 2.73, 4.70) times per week (effect size 0.62), and decreased refined carbohydrates by 3.77 (95% CI 3.10, 4.44) times per week both significantly (P

Published
2016

5. Randomized phase 2 trial of NP001-a novel immune regulator: Safety and early efficacy in ALS.

Author

McGrath, Michael, Miller, RG, Block, G, Katz, JS, Barohn, RJ, Gopalakrishnan, V, Cudkowicz, M, Zhang, JR, McGrath, MS, Ludington, E, and Appel, SH

Abstract

To assess the safety, tolerability, and preliminary efficacy of NP001, a novel immune regulator of inflammatory monocytes/macrophages, for slowing progression of amyotrophic lateral sclerosis (ALS).This was a phase 2 randomized, double-blind, placebo-contr

Published
2015

7. Breastfeeding patterns and risk of childhood acute lymphoblastic leukaemia.

Author

Kwan, ML, Buffler, PA, Wiemels, JL, Metayer, C, Selvin, S, Ducore, JM, and Block, G

Subjects
Humans, Bottle Feeding, Diet, Risk Factors, Case-Control Studies, Breast Feeding, Time Factors, Infant Food, Adolescent, Child, Child, Preschool, Infant, Female, Male, Precursor Cell Lymphoblastic Leukemia-Lymphoma, Surveys and Questionnaires, Preschool, Oncology & Carcinogenesis, Oncology and Carcinogenesis, Public Health and Health Services
Abstract

The risk of childhood acute lymphoblastic leukaemia (ALL) was investigated in relation to breastfeeding patterns in the Northern California Childhood Leukaemia Study. Data collected by self-administered and in-person questionnaires from biological mothers of leukaemia cases (age 0-14 years) in the period 1995-2002 were matched to birth certificate controls on date of birth, sex, Hispanic ethnic status, and maternal race. Ever compared to never breastfeeding was not associated with risk of ALL at ages 1-14 years (odds ratio=0.99; 95% CI=0.64-1.55) and ages 2-5 years (OR=1.49; 95% CI=0.83-2.65). Various measures of breastfeeding duration compared to absence of breastfeeding also had no significant effect on risk. Complimentary feeding characteristics such as type of milk/formula used and age started eating solid foods among breastfed children were not associated with ALL risk. This study provides no evidence that breastfeeding affects the occurrence of childhood ALL.

Published
2005

10. A randomized trial of the little by little cd-rom: Demonstrated effectiveness in increasing fruit and vegetable intake in a low-income population

Author

Block, G, Wakimoto, P, Metz, D, Fujii, ML, Feldman, N, Mandel, R, and Sutherland, B

Subjects
Public Health and Health Services
Abstract

Introduction Research indicates that low fruit and vegetable intake is a risk factor for many chronic diseases. Despite large-scale education campaigns, the great majority of Americans do not consume recommended levels. We tested the ability of a single brief interactive experience of the Little by Little CD-ROM to increase fruit and vegetable intake in lowincome women. Methods A randomized placebo-controlled, parallel-group trial included 481 low-income, female participants: mean age 50.1 years, 48.4% African American, 51.6% non- Hispanic white, and 92.5% below 185% of the federally designated poverty level. Participants received one of three conditions: 1) a one-time experience with the Little by Little CD-ROM, 2) the Little by Little CD-ROM plus two reminder telephone calls, or 3) a stress management CD-ROM (control condition). We assessed baseline and follow-up dietary intake with a modified 24-hour recall. Results Two months after the one-time experience with the CDROMs, both intervention groups reported significantly higher intakes of fruits and vegetables than the control group. The Little by Little group with reminder calls increased daily intake by 1.32 fruits/vegetables, an 86% greater increase than the control group (P = .016). The Little by Little group without reminder calls increased daily intake by 1.20 fruits/vegetables, a 69% greater increase than the control group (P = .052). Significantly greater movement in Stage of Readiness for Change also occurred in the Little by Little groups compared with the control group. Conclusion The Little by Little CD-ROM may be useful in public health and clinical situations to increase fruit and vegetable intake.

Published
2004

11. A malnutrition-inflammation score is correlated with morbidity and mortality in maintenance hemodialysis patients.

Author

Kalantar-Zadeh, K, Kopple, JD, Block, G, and Humphreys, MH

Subjects
Humans, Anemia, Nutrition Disorders, Syndrome, Inflammation, Serum Albumin, Anthropometry, Body Mass Index, Hospitalization, Renal Dialysis, Nutrition Assessment, Survival Rate, Proportional Hazards Models, Risk Assessment, Comorbidity, Age Distribution, Sex Distribution, Adult, Aged, Aged, 80 and over, Middle Aged, Outcome Assessment (Health Care), San Francisco, Female, Male, Outcome Assessment, Health Care, dialysis, malnutrition, inflammation, nutritional assessment, hospitalization, mortality, near infrared, albumin, transferrin, C-reactive protein, and over, Outcome Assessment, Health Care, Urology & Nephrology, Clinical Sciences, Public Health and Health Services
Abstract

Malnutrition inflammation complex syndrome (MICS) occurs commonly in maintenance hemodialysis (MHD) patients and may correlate with increased morbidity and mortality. An optimal, comprehensive, quantitative system that assesses MICS could be a useful measure of clinical status and may be a predictor of outcome in MHD patients. We therefore attempted to develop and validate such an instrument, comparing it with conventional measures of nutrition and inflammation, as well as prospective hospitalization and mortality. Using components of the conventional Subjective Global Assessment (SGA), a semiquantitative scale with three severity levels, the Dialysis Malnutrition Score (DMS), a fully quantitative scoring system consisting of 7 SGA components, with total score ranging between 7 (normal) and 35 (severely malnourished), was recently developed. To improve the DMS, we added three new elements to the 7 DMS components: body mass index, serum albumin level, and total iron-binding capacity to represent serum transferrin level. This new comprehensive Malnutrition-Inflammation Score (MIS) has 10 components, each with four levels of severity, from 0 (normal) to 3 (very severe). The sum of all 10 MIS components ranges from 0 to 30, denoting increasing degree of severity. These scores were compared with anthropometric measurements, near-infrared-measured body fat percentage, laboratory measures that included serum C-reactive protein (CRP), and 12-month prospective hospitalization and mortality rates. Eighty-three outpatients (44 men, 39 women; age, 59 +/- 15 years) on MHD therapy for at least 3 months (43 +/- 33 months) were evaluated at the beginning of this study and followed up for 1 year. The SGA, DMS, and MIS were assessed simultaneously on all patients by a trained physician. Case-mix-adjusted correlation coefficients for the MIS were significant for hospitalization days (r = 0.45; P < 0.001) and frequency of hospitalization (r = 0.46; P < 0.001). Compared with the SGA and DMS, most pertinent correlation coefficients were stronger with the MIS. The MIS, but not the SGA or DMS, correlated significantly with creatinine level, hematocrit, and CRP level. During the 12-month follow-up, 9 patients died and 6 patients left the cohort. The Cox proportional hazard-calculated relative risk for death for each 10-unit increase in the MIS was 10.43 (95% confidence interval, 2.28 to 47.64; P = 0.002). The MIS was superior to its components or different subversions for predicting mortality. The MIS appears to be a comprehensive scoring system with significant associations with prospective hospitalization and mortality, as well as measures of nutrition, inflammation, and anemia in MHD patients. The MIS may be superior to the conventional SGA and the DMS, as well as to individual laboratory values, as a predictor of dialysis outcome and an indicator of MICS.

Published
2001

12. Dietary intake, dietary patterns, and changes with age: an epidemiological perspective.

Author

Wakimoto, P and Block, G

Subjects
Humans, Nutrition Disorders, Minerals, Vitamins, Epidemiologic Methods, Cohort Studies, Longitudinal Studies, Cross-Sectional Studies, Feeding Behavior, Energy Intake, Nutritional Requirements, Nutritive Value, Aging, Research, Nutrition Policy, Aged, Aged, 80 and over, Middle Aged, Health Promotion, United States, Female, Male, Gerontology, Clinical Sciences
Abstract

Cohort and cross-sectional data were reviewed to describe the changes in dietary intake with age. Total energy intake decreases varied substantially with age, by 1000 to 1200 kcal in men and by 600 to 800 kcal in women. This resulted in concomitant declines in most nutrient intakes. For some nutrients, substantial numbers of older Americans consumed only one fifth to one third of the recommended dietary allowance. For most nutrients, research is lacking with which to judge the health impact of reduced nutrient consumption with age, although there is some evidence of an age-related decline in absorptive and metabolic function. With the aging of the population, more research is needed on nutrient requirements and health outcomes, and public health efforts are needed to increase physical activity and food intake among older people.

Published
2001

24. Helicobacter pylori infection and the risk of Barrett's oesophagus: a community-based study

Author

Corley, D.A., Kubo, A., Levin, T.R., Block, G., Habel, L., Zhao, W., Leighton, P., Rumore, G., Quesenberry, C., Buffler, P., and Parsonnet, J.

Subjects
Helicobacter infections -- Complications and side effects, Helicobacter infections -- Genetic aspects, Helicobacter infections -- Research, Barrett's esophagus -- Risk factors, Barrett's esophagus -- Development and progression, Barrett's esophagus -- Research, Health
Published
2008

32. Fusionsbiopsie Urologische GMP SLS 2015–2018

Author

Block, G, Bauer, E, Radulescu, M, and Radulescu, F

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Daten von 70 Pat. aus der urologischen Gemeinschaftspraxis / Belegabteilung DRK Saarlouis aus den Jahren 2015-2018 Indikation mpMRT Prädiktion Technik und Sytem praktische Durchführung histologische Realita „Trefferquote“ Ergebnisbewertun[zum vollständigen Text gelangen Sie über die oben angegebene URL], 60. Jahrestagung der Südwestdeutschen Gesellschaft für Urologie e.V.

Published
2019
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44. American Society of Colon and Rectal Surgeons 91st Annual Convention Podium and Poster abstracts: June 7–12, 1992 San Francisco, CA

Author

Lechner, P., Lind, P., Binter, G., Golub, R. W., Kerner, B. A., Wise, Jr., W. E., Meesig, D. M., Hartmann, R. F., Khanduja, K. S., Sayre, J. W., Aguilar, P. S., Guillem, J. G., Forde, K. A., Treat, M. R., Neugut, A. I., O'Toole, K. M., Diamond, B. E., Kewenter, J., Brevinge, H., Haglind, E., Limberg, B., Elles, C. N., Boggs, W. H., Slagle, G. H., Cole, P. A., Coyle, D. J., Smith, L. E., Orkin, B., Saclarides, T. J., Sheridan, W. G., Lowndes, R. H., Young, H. L., Wong, W. D., Rothenberger, D. A., Bartolo, D. C. C., Wexner, S. D., Ger, G. C., Jorge, J. M. N., Lee, E., Nogueras, J. J., Jagelman, D. G., McKenna, K., Koltun, W. A., Bute, B., Lichliter, W., Le, T., Timmcke, A., Gathright, J. B., Mascagni, D., Hojo, K., Moriya, Y., Sugihara, K., Di, G., Zenni, G. C., Abraham, K., Dobrin, P. B., Harford, F. J., Suzuki, K., Gunderson, L., Devine, R. M., Dozois, R. R., Cavaliere, F., Pemberton, J. H., Fazio, V., Cosimelli, M., Beart, R. W., Giannarelli, D., Moran, M., Ramos, A., Rothenberger, D., Goldberg, S., Antonenko, D., Heymen, S., Gulledge, A. D., Jakate, S., Saclarides, T., Heine, J. A., Williams, J. G., VanBergen, E. H., Buie, W. D., Goldberg, S. M., Davies, N., Yates, J., Jenkins, S. A., Taylor, B. A., Bapat, B., Stern, H., Berk, T., Parker, J., Ray, P. N., McLeod, R., Cohen, Z., Rowe, J. K., Zera, R. T., Madoff, R. D., Bubrick, M. P., Roberts, J. C., Johnston, G. R., Fenney, D. A., Farouk, R., Duthie, G. S., McCue, J. L., Phillips, R. K. S., Viamonte, M., Cole, J., Gottesman, L., Solomon, M. J., McLeod, R. S., Kern, K., Jensen, L. L., Lowry, A. C., Vernava, III, A. M., Longo, W. E., Daniel, G. L., Ehrenpreis, E., Stone, J. M., Cosman, B. C., Wolfe, V. A., Nino-Murcia, M., Perkash, I., Marcello, P. W., Roberts, P. L., Schoetz, Jr., D. J., Murray, J. J., Coller, J. A., Veidenheimer, M. C., Keighley, M. R. B., Grobler, S. P., Hosie, K. B., Schmitt, S. L., James, K., Lucas, F., Peck, Donald A., Ferrara, A., Grotz, R. L., Perry, R. E., Hanson, R. B., Lewis, W. G., Holdsworth, P. J., Sagar, P. M., Johnston, D., Perry, T. G., Strong, S. A., Fazio, V. W., Lavery, I. C., Oakley, J. R., Church, J. M., Milsom, J. W., Fozard, J. B. J., Nelson, H., Schneebaum, S., Arnold, M. W., Young, D., LaValle, G. J., Petty, L., Berens, A., Mojizisik, C., Martin, E. W., Hase, K., Shatney, C. H., Trollope, M., Johnson, D., Vierra, M., Deutsch, A. A., Tulchinsky, H., Nudelman, I., Gutman, H., Reiss, R., Taylor, Brian M., Araujo, A., Bleday, R., Jessurun, J., Heine, J., Rosen, Les, Sipe, Paul, Riether, Robert, Stasik, John, Sheets, James, Khubchandani, Indru, Reiter, W., Friedberg, G., Morey, G., Goldstein, E., Williamson, P., Larach, S., Senagore, A. J., Luchtefeld, M. A., MacKeigen, J. M., Mazier, W. P., Wengert, T., Ott, M. T., Bailey, H. R., Hartendorp, P., Dailey, T. H., Church, J. C., Johansen, O. B., Daniel, N., Korst, M., Kuijpers, H. C., Pena, J. P., Christenson, C. E., Balcos, E. G., Lewis, W., Mitchell, C., MacFie, J., Hildebrandt, U., Ecker, K. W., Kraus, J., Schmid, T., Feifel, G., Tjandra, J. J., Scoggin, Steve, Frazee, Richard C., Ambroze, Jr., W. L., Nezhat, C., Pennington, E., Nezhat, F., Stolfi, V. M., Thorson, A. G., Falk, P. M., Fitzgibbons, Jr, R. J., Luukkonen, P., Järvinen, H. J., James, E., Paty, P. B., Enker, W. E., Cohen, A. M., Lauwers, G. Y., Saad, R., Birnbaum, E., DeVos, W., Fry, R., Kodner, I., Fleshman, J., Cali, R. L., Pitsch, R. M., Blatchford, G. J., Christensen, M. A., Schroeder, T. K., Easley, K. A., Ellis, C. N., Cheape, J. D., Hull, T. L., Salanga, V., Kokoszka, Joseph, Andrianopoulos, Georgia, Nelson, Richard, Abcarian, Herand, Kumar, D., Benson, M. J., Roberts, J., Martin, J. E., Swash, M., Wingate, D. L., Williams, N. S., Orkin, B. A., Emsellem, H., Dent, John, Tissaw, M. A., Shafik, A., Abel, M. E., Chiu, Y. S. Y., Russell, T. R., Volpe, P. A., Casillas, G. L., Mashas, W. E., Eastman, D. A., Grace, R. H., Anderson, J. M., Hacker, K., Heryer, J., Conner, W., Rubin, R., Eisenstat, T., Salvati, E., Oliver, G., Duberman, E., Simmang, C. L., Fry, R. D., Kodner, I. J., Fleshman, J. W., Corman, M. L., Galandiuk, S., Weiner, G. J., Kahn, D., Mitchell, E., Abdel-Nabi, H., Block, G. E., Mannella, E., Tedesco, M., Anza, M., Civalleri, D., Di Tora, P., Capussotti, L., Morandi, G. B., Tirelli, C., Da Pian, P. P., Cortesi, E., Ruggeri, E., Fitzgerald, S. D., Davis, Faith, Bowen, Phyllis, Sutter, Eileen, Kikendall, Walter, McGannon, E., Brantley, P. A., Czyrko, C., Falardeau, C., Trepashko, Don, Skosey, John, Michelassi, F., Staniunas, R. J., Vignati, P. V., Beck, D. E., Karulf, R., Roettger, R., Braidt, J., Ruoff, K., Ackroyd, F., Shellito, P., Goh, H. S., Lin, L. W., Edwards, E., Farmer, J., Walters, C. A., Hyman, N. H., Hebert, J. C., Richman, Irving M., Staren, E. D., Sessions, S. C., Scoma, R. S., Clements, B., Smink, Jr., R. D., Arai, K., Sugita, A., Yamazaki, Y., Harada, H., Fukushima, T., Armstrong, D. N., Ballantyne, G. H., Sillin, L. F., Davie, R. J., Harding, L. K., Birch, N. J., Yamanouchi, T., Bayer, I., Mitmaker, B., Gordon, P. H., Wang, E., Kynaston, H., Edelstein, P. S., Thompson, S. M., Davies, R. J., Farmer, K. C. R., Oliver, S. E., Spigelman, A. D., Bennett, P., O'Kelly, T. J., Brading, A. F., Mortensen, N. J., Paul, P., McGannon, E. M., Huth, P., Hull-Boiner, S., Pezim, M. E., Johnson, H. W., Gillespie, K. D., Willard, P., Owen, D. A., Ramsey, P. S., Leu, S. Y., Hsu, H., Al-Humadi, Adil H., Eisman, E., Tries, J., Gupta, N. C., Frick, M. P., Boman, B. M., Franceschi, D., Eckhauser, M. L., Pritchard, T., Konsten, J., Baeten, C. G. M. I., Havenith, M. G., Soeters, P. B., Lau, P. W. K., Lorentz, T. G., Wong, J., and The III In-CYT-103 Immunoscintigraphy Study Group

Published
1992
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46. Cardiovascular tissues contain independent circadian clocks

Author

Davidson, A. J, London, B, Block, G. D, and Menaker, M

Subjects
Life Sciences (General)
Abstract

Acute cardiovascular events exhibit a circadian rhythm in the frequency of occurrence. The mechanisms underlying these phenomena are not yet fully understood, but they may be due to rhythmicity inherent in the cardiovascular system. We have begun to characterize rhythmicity of the clock gene mPer1 in the rat cardiovascular system. Luciferase activity driven by the mPer1 gene promoter is rhythmic in vitro in heart tissue explants and a wide variety of veins and arteries cultured from the transgenic Per1-luc rat. The tissues showed between 3 and 12 circadian cycles of gene expression in vitro before damping. Whereas peak per1-driven bioluminescence consistently occurred during the late night in the heart and all arteries sampled, the phases of the rhythms in veins varied significantly by anatomical location. Varying the time of the culture procedure relative to the donor animal's light:dark cycle revealed that, unlike some other rat tissues such as liver, the phases of in vitro rhythms of arteries, veins, and heart explants were affected by culture time. However, phase relationships among tissues were consistent across culture times; this suggests diversity in circadian regulation among components of the cardiovascular system.

Published
2005

47. Nutrititional Status Assessment of International Space Station Crew Members

Author

Smith, S. M, Zwart, S. R, Block, G, Rice, B. I, and Davis-Street, J. F

Subjects
Aerospace Medicine
Abstract

Defining optimal nutrient requirements is imperative to ensure crew health on long-duration space exploration missions. To date, nutrient requirement data have been extremely limited because of small sample sizes and difficulties associated with collecting biological samples. In this study, we examined changes in body composition, bone metabolism, hematology, general blood chemistry, and blood levels of selected vitamins and minerals after long-duration (128-195 d) space flight aboard the International Space Station. Crew members consumed an average of 80% of the recommended energy intakes, and on landing day their body weight had decreased (P=0.051). After flight, hematocrit was less, and serum femtin was greater than before flight (P<0.01). Serum iron, ferritin saturation, and transferrin had decreased after flight. The finding that other acute-phase proteins, including ceruloplasmin, retinol binding protein, transthyretin, and albumin were not changed after flight suggests that the changes in iron metabolism may not be strictly due to an inflammatory response. Urinary 8- hydroxy-2'-deoxyguanosine concentration was greater and superoxide dismutase was less after flight, indicating that oxidative damage had increased (P<0.05). Despite the reported use of vitamin D supplements during flight, serum 25-hydroxyvitamin D was significantly decreased after flight (P<0.01). Bone resorption was increased after flight, as indicated by several urinary markers of bone resorption. Bone formation, assessed by serum concentration of bone-specific alkaline phosphatase, was elevated only in crew members who landed in Russia, probably because of the longer time lapse between landing and sample collection. These data provide evidence that bone loss, compromised vitamin D status, and oxidative damage remain critical concerns for long-duration space flight.

Published
2005

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