Calculations of Hubbard U from first-principles

The Hubbard \emph{U} of the \emph{3d} transition metal series as well as SrVO$_{3}$, YTiO$_{3}$, Ce and Gd has been estimated using a recently proposed scheme based on the random-phase approximation. The values obtained are generally in good accord with the values often used in model calculations but for some cases the estimated values are somewhat smaller than those used in the literature. We have also calculated the frequency-dependent \emph{U} for some of the materials. The strong frequency dependence of \emph{U} in some of the cases considered in this paper suggests that the static value of \emph{U} may not be the most appropriate one to use in model calculations. We have also made comparison with the constrained LDA method and found some discrepancies in a number of cases. We emphasize that our scheme and the constrained LDA method theoretically ought to give similar results and the discrepancies may be attributed to technical difficulties in performing calculations based on currently implemented constrained LDA schemes.Comment: 24 pages, 13 figures; Submitted to Phys. Rev.

Sustainability of exercise-induced increases in bone density and skeletal structure

BACKGROUND: The prevalence of osteoporosis with related fragility fractures has increased during the last decades. As physical activity influences the skeleton in a beneficial way, exercise may hypothetically be used as a prophylactic tool against osteoporosis. OBJECTIVE: This review evaluates if exercise-induced skeletal benefits achieved during growth remain in a long-term perspective. DESIGN: PUBLICATIONS WITHIN THE FIELD WERE SEARCHED THROUGH MEDLINE (PUBMED) USING THE SEARCH WORDS: exercise, physical activity, bone mass, bone mineral content (BMC), bone mineral density (BMD) and skeletal structure. We based our inferences on publications with the highest level of evidence, particularly randomised controlled trials (RCT). RESULTS: Benefits in BMD achieved by exercise during growth seem to be eroded at retirement, but benefits in skeletal structure may possibly be retained in a longer perspective. Recreational exercise seems to at least partially maintain exercise-induced skeletal benefits achieved during growth. CONCLUSIONS: Exercise during growth may be followed by long-term beneficial skeletal effects, which could possibly reduce the incidence of fractures. Exercise during adulthood seems to partly preserve these benefits and reduce the age-related bone loss

Physical activity increases bone mass during growth

BACKGROUND: The incidence of fragility fractures has increased during the last half of the 1990's. One important determinant of fractures is the bone mineral content (BMC) or bone mineral density (BMD), the amount of mineralised bone. If we could increase peak bone mass (the highest value of BMC reached during life) and/or decrease the age-related bone loss, we could possibly improve the skeletal resistance to fracture. OBJECTIVE: This review evaluates the importance of exercise as a strategy to improve peak bone mass, including some aspects of nutrition. DESIGN: PUBLICATIONS WITHIN THE FIELD WERE SEARCHED THROUGH MEDLINE (PUBMED) USING THE SEARCH WORDS: exercise, physical activity, bone mass, bone mineral content, bone mineral density, BMC, BMD, skeletal structure and nutrition. We included studies dealing with exercise during growth and young adolescence. We preferably based our inferences on randomised controlled trials (RCT), which provide the highest level of evidence. RESULTS: Exercise during growth increases peak bone mass. Moderate intensity exercise intervention programs are beneficial for the skeletal development during growth. Adequate nutrition must accompany the exercise to achieve the most beneficial skeletal effects by exercise. CONCLUSION: Exercise during growth seems to enhance the building of a stronger skeleton through a higher peak bone mass and a larger bone size

Human papillomavirus-associated oropharyngeal cancer: a new clinical entity

The incidence of oropharyngeal cancers is rising worldwide in both nonsmokers and nondrinkers. Epidemiology studies suggest a strong association between human papillomavirus (HPV) 16 infection, changing sexual behavior and cancer development. Despite initial presentation with locally advanced disease and poorly differentiated histology, HPV-associated oropharyngeal carcinoma is associated with a good prognosis because its response to chemotherapy and radiation. Clinicians should be aware of the risk of oropharyngeal cancer in young people to avoid unnecessary delay in diagnosis and treatment. A history of oral sex should be elicited in young patients with enlarged neck nodes and/or tonsillar masse

Both apoptosis and necrosis occur early after intracerebral grafting of ventral mesencephalic tissue: a role for protease activation.

Neural transplantation is an experimental treatment for Parkinson's disease. Widespread clinical application of the grafting technique is hampered by a relatively poor survival (around 10%) of implanted embryonic dopamine neurones. Earlier animal studies have indicated that a large proportion of the grafted cells die during graft tissue preparation and within the first few days after intracerebral implantation. The present study was designed to reveal the prevalence of cell death in rat intrastriatal grafts at 90 min, 1, 3, 6 and 42 days after implantation. We examined apoptotic cell death using semi-thin and paraffin sections stained with methylene blue and an antibody against activated caspase 3, respectively. We identified abundant apoptotic cell death up to 3 days after transplantation. In addition, we studied calpain activation using an antibody specific for calpain-cleaved fodrin. We report a peak in calpain activity 90 min after grafting. Surprisingly, we did not observe any significant difference in the number of dopaminergic neurones over time. The present results imply that grafted cells may be victims of either an early necrotic or a later apoptotic cell death and that there is substantial cell death as early as 90 min after implantation

Isotopic ratios of H, C, N, O, and S in comets C/2012 F6 (Lemmon) and C/2014 Q2 (Lovejoy)

The apparition of bright comets C/2012 F6 (Lemmon) and C/2014 Q2 (Lovejoy) in March-April 2013 and January 2015, combined with the improved observational capabilities of submillimeter facilities, offered an opportunity to carry out sensitive compositional and isotopic studies of the volatiles in their coma. We observed comet Lovejoy with the IRAM 30m telescope between 13 and 26 January 2015, and with the Odin submillimeter space observatory on 29 January - 3 February 2015. We detected 22 molecules and several isotopologues. The H$_2^{16}$O and H$_2^{18}$O production rates measured with Odin follow a periodic pattern with a period of 0.94 days and an amplitude of ~25%. The inferred isotope ratios in comet Lovejoy are $^{16}$O/$^{18}$O = 499 $\pm$ 24 and D/H = 1.4 $\pm$ 0.4 $\times 10^{-4}$ in water, $^{32}$S/$^{34}$S = 24.7 $\pm$ 3.5 in CS, all compatible with terrestrial values. The ratio $^{12}$C/$^{13}$C = 109 $\pm$ 14 in HCN is marginally higher than terrestrial and $^{14}$N/$^{15}$N = 145 $\pm$ 12 in HCN is half the Earth ratio. Several upper limits for D/H or 12C/13C in other molecules are reported. From our observation of HDO in comet C/2014 Q2 (Lovejoy), we report the first D/H ratio in an Oort Cloud comet that is not larger than the terrestrial value. On the other hand, the observation of the same HDO line in the other Oort-cloud comet, C/2012 F6 (Lemmon), suggests a D/H value four times higher. Given the previous measurements of D/H in cometary water, this illustrates that a diversity in the D/H ratio and in the chemical composition, is present even within the same dynamical group of comets, suggesting that current dynamical groups contain comets formed at very different places or times in the early solar system.Comment: Accepted for publication in Astronomy and Astrophysic

Older breast cancer undertreatment: Unconscious bias to undertreat-potential role for the international geriatric radiotherapy group?

The prevalence of breast cancer increases with age. Older breast cancer patients often present with locally advanced disease at presentation because mammography, which diagnosed early stage disease, is not recommended after the age of 75. In addition, they are often undertreated even when they are physically fit and have non-metastatic disease. As a result, survival is often poor. Physicians bias may be a factor in their undertreatment and lack of representation in prospective clinical trials. Physicians should be educated that chronological age is not a contraindication to curative treatment for older breast cancer patients. As a research group devoted to older cancer patients, women, and minorities, the International Geriatric Radiotherapy Group (IGRG) plans to conduct prospective trials to assess biomarkers for frailty, the controversial issue of mammography for older breast cancer patients, and the incorporation of frailty index for curative breast cancer treatment. The data obtained may help to decrease physician bias and to establish future guidelines for older breast cancer patients treatment