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1.
J Occup Environ Med ; 59(12): e288-e296, 2017 12.
Article in English | MEDLINE | ID: mdl-29215484

ABSTRACT

OBJECTIVE: The aim of this study was to investigate a cohort in German hardmetal industry, especially relationship between exposures to cobalt, with and without tungsten, and risks of total and cause-specific mortality. METHODS: The cohort comprises blue-collar workers at three German plants who were employed in hardmetal processing. Individual cumulative exposures and long-term average concentrations were estimated for cobalt, nickel, tungsten, respirable, and inhalable dust. Standardized mortality ratios (SMRs) were calculated for external comparisons. Time-dependent multivariable Cox models were performed for internal analyses. RESULTS: Elevated SMRs were found for all-cause, heart diseases, and nonmalignant respiratory diseases mortality, but not for lung cancer. Internal analyses did not show increased risks for any endpoints, and no exposure-response relationship was indicated. CONCLUSIONS: This study does not provide evidence for elevated lung cancer risks. Methodologic limitations, incomplete ascertainment of death causes in particular, impede conclusions about exposure effects.


Subject(s)
Alloys/adverse effects , Chemical Industry/statistics & numerical data , Cobalt/adverse effects , Lung Neoplasms/mortality , Occupational Diseases/mortality , Occupational Exposure/adverse effects , Tungsten/adverse effects , Adolescent , Adult , Aged, 80 and over , Cause of Death , Cohort Studies , Female , Germany , Humans , Lung Neoplasms/chemically induced , Male , Middle Aged , Occupational Exposure/statistics & numerical data , Proportional Hazards Models , Retrospective Studies , Risk Factors , Young Adult
2.
J Occup Environ Med ; 59(12): e342-e364, 2017 12.
Article in English | MEDLINE | ID: mdl-29215487

ABSTRACT

OBJECTIVES: Based on a pooled analysis of data from an international study, evaluate total and cause-specific mortality among hardmetal production workers with emphasis on lung cancer. METHODS: Study members were 32,354 workers from three companies and 17 manufacturing sites in five countries. We computed standardized mortality ratios and evaluated exposure-response via relative risk regression analysis. RESULTS: Among long-term workers, we observed overall deficits or slight excesses in deaths for total mortality, all cancers, and lung cancer and found no evidence of any exposure-response relationships for lung cancer. CONCLUSIONS: We found no evidence that duration, average intensity, or cumulative exposure to tungsten, cobalt, or nickel, at levels experienced by the workers examined, increases lung cancer mortality risks. We also found no evidence that work in these facilities increased mortality risks from any other causes of death.


Subject(s)
Alloys/adverse effects , Cobalt/adverse effects , Lung Neoplasms/mortality , Occupational Diseases/mortality , Occupational Exposure/adverse effects , Tungsten/adverse effects , Adult , Cause of Death , Chemical Industry/statistics & numerical data , Female , Humans , Lung Neoplasms/chemically induced , Male , Occupational Exposure/statistics & numerical data , Risk Factors
3.
Science ; 356(6341): 933-938, 2017 06 02.
Article in English | MEDLINE | ID: mdl-28572387

ABSTRACT

Little is known about how stony corals build their calcareous skeletons. There are two prevailing hypotheses: that it is a physicochemically dominated process and that it is a biologically mediated one. Using a combination of ultrahigh-resolution three-dimensional imaging and two-dimensional solid-state nuclear magnetic resonance (NMR) spectroscopy, we show that mineral deposition is biologically driven. Randomly arranged, amorphous nanoparticles are initially deposited in microenvironments enriched in organic material; they then aggregate and form ordered aragonitic structures through crystal growth by particle attachment. Our NMR results are consistent with heterogeneous nucleation of the solid mineral phase driven by coral acid-rich proteins. Such a mechanism suggests that stony corals may be able to sustain calcification even under lower pH conditions that do not favor the inorganic precipitation of aragonite.


Subject(s)
Anthozoa/physiology , Calcium Carbonate/metabolism , Animals , Anthozoa/growth & development , Anthozoa/ultrastructure , Calcification, Physiologic/physiology , Carbonates/analysis , Cellular Microenvironment/physiology , Crystallization , Magnetic Resonance Spectroscopy , Microscopy, Electron, Scanning , Nonlinear Optical Microscopy
4.
Meteorit Planet Sci ; 52(5): 949-978, 2017 May.
Article in English | MEDLINE | ID: mdl-30498327

ABSTRACT

Miller Range (MIL) 090340 and MIL 090206 are olivine-rich achondrites originally classified as ureilites. We investigate their petrography, mineral compositions, olivine Cr valences, equilibration temperatures, and (for MIL 090340) oxygen isotope compositions, and compare them with ureilites and other olivine-rich achondrites. We conclude that they are brachinite-like achondrites that provide new insights into the petrogenesis of brachinite clan meteorites. MIL 090340,6 has a granoblastic texture and consists of ~97 modal % by area olivine (Fo = molar Mg/[Mg+Fe] = 71.3±0.6). It also contains minor to trace augite, chromite, chlorapatite, orthopyroxene, metal, troilite, and terrestrial Fe-oxides. Approximately 80% by area of MIL 090206,5 has a granoblastic texture of olivine (Fo 72.3±0.1) plus minor augite and chromite, similar to MIL 090340 but also containing minor plagioclase. The rest of the section consists of a single crystal of orthopyroxene (~11×3 mm), poikilitically enclosing rounded grains of olivine (Fo = 76.1±0.6), augite, chromite, metal and sulfide. Equilibration temperatures for MIL 090340 and MIL 090206, calculated from olivine-spinel, olivine-augite, and two-pyroxene thermometry range from ~800-930°C. In both samples, symplectic intergrowths of Ca-poor orthopyroxene + opaque phases (Fe-oxides, sulfide, metal) occur as rims on and veins/patches within olivine. Before terrestrial weathering, the opaques were probably mostly sulfide, with minor metal. All petrologic properties of MIL 090340 and MIL 090206 are consistent with those of brachinite clan meteorites, and largely distinct from those of ureilites. Oxygen isotope compositions of olivine in MIL 090340 (δ18O = 5.08±0.30‰, δ17O = 2.44±0.21‰, and Δ17O = -0.20±0.12‰) are also within the range of brachinite clan meteorites, and well distinguished from ureilites. Olivine Cr valences in MIL 090340 and the granoblastic area of MIL 090206 are 2.57±0.06 and 2.59±0.07, respectively, similar to those of three brachinites also analyzed here (Brachina, Hughes 026, Nova 003). They are higher than those of olivine in ureilites, even those containing chromite. The valence systematics of MIL 090340, MIL 090206, and the three analyzed brachinites (lower Fo = more oxidized Cr) are consistent with previous evidence that brachinite-like parent bodies were inherently more oxidized than the ureilite parent body. The symplectic orthopyroxene + sulfide/metal assemblages in MIL 090340, MIL 090206, and many brachinite clan meteorites have superficial similarities to characteristic "reduction rims" in ureilites. However, they differ significantly in detail. They likely formed by reaction of olivine with S-rich fluids, with only minor reduction. MIL 090340 and the granoblastic area of MIL 090206 are similar in modal mineralogy and texture to most brachinites, but have higher Fo values typical of brachinite-like achondrites. The poiklitic pyroxene area of MIL 090206 is more typical of brachinite-like achondrites. The majority of their properties suggest that MIL 090340 and MIL 090206 are residues of low-degree partial melting. The poikilitic area of MIL 090206 could be a result of limited melt migration, with trapping and recrystallization of a small volume of melt in the residual matrix. These two samples are so similar in mineral compositions, Cr valence, and cosmic ray exposure ages that they could be derived from the same lithologic unit on a common parent body.

6.
Sci Adv ; 1(8): e1500380, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26601265

ABSTRACT

The Moon contains chlorine that is isotopically unlike that of any other body yet studied in the Solar System, an observation that has been interpreted to support traditional models of the formation of a nominally hydrogen-free ("dry") Moon. We have analyzed abundances and isotopic compositions of Cl and H in lunar mare basalts, and find little evidence that anhydrous lava outgassing was important in generating chlorine isotope anomalies, because (37)Cl/(35)Cl ratios are not related to Cl abundance, H abundance, or D/H ratios in a manner consistent with the lava-outgassing hypothesis. Instead, (37)Cl/(35)Cl correlates positively with Cl abundance in apatite, as well as with whole-rock Th abundances and La/Lu ratios, suggesting that the high (37)Cl/(35)Cl in lunar basalts is inherited from urKREEP, the last dregs of the lunar magma ocean. These new data suggest that the high chlorine isotope ratios of lunar basalts result not from the degassing of their lavas but from degassing of the lunar magma ocean early in the Moon's history. Chlorine isotope variability is therefore an indicator of planetary magma ocean degassing, an important stage in the formation of terrestrial planets.

8.
Psychooncology ; 22(11): 2611-6, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23784985

ABSTRACT

OBJECTIVE: The results of studies concerning levels of internalizing and externalizing behaviors in adolescent children with a parent suffering from cancer as compared with control groups or normative data are contradictory so far. Longitudinal designs using control groups are rare. No study explicitly exploring a broad range of risk behaviors in adolescent children with a parent suffering from cancer exists to date. METHODS: Therefore, 74 adolescents who have a parent with cancer (index group) were compared with 75 adolescents with healthy parents (control group) concerning several juvenile risk behaviors and externalizing behaviors. Participants were examined three times over the course of 12 months. RESULTS: No significant main effects for group or interactional effects of group with time could be found for any of the measured variables. CONCLUSIONS: Results suggest that the somatic illness of the parent is not a developmental risk that is expressed in increased levels of juvenile risk behavior. Adolescents with a parent suffering from cancer adjusted generally quite well to the parental illness, although some individuals did show signs of severe strain.


Subject(s)
Adolescent Behavior/psychology , Child of Impaired Parents/psychology , Internal-External Control , Juvenile Delinquency/psychology , Neoplasms/psychology , Parents/psychology , Adolescent , Child , Female , Humans , Logistic Models , Longitudinal Studies , Male , Parent-Child Relations , Psychiatric Status Rating Scales/statistics & numerical data , Risk-Taking , Socioeconomic Factors , Surveys and Questionnaires , Young Adult
9.
Article in German | MEDLINE | ID: mdl-22950336

ABSTRACT

By the current state of research, it cannot be answered clearly how adolescents experience anticipatory grief and if and to which extent this process differs from anticipatory grief of adults. The present study will fill this gap by providing both a quantitative and a qualitative description of anticipatory grief processes. Therefore, 74 adolescents and young adults (11-21 years), whose parents have suffered from cancer, completed an adapted version of the "Trauerfragebogen" (Weiser u. Ochsmann, 2002). Additionally a subsample of n = 38 took part in a qualitative guided interview. Based on these interviews, 16 categories were formed, that were assigned to two types of stressors. Beside communication and prioritization of family, different symptoms of grief were the central category in the loss-oriented type, where fears of loss, compassion and concern were of crucial importance. Also categories of the restoration-oriented type were strongly present. Thus, it seems that young people generally manage to accept their new role in the stressful family situation and they have a series of coping mechanisms available to do so. This was also reflected in the quantitative data, were the subscale "Inner Strength" reached the highest value. In the counselling of adolescents with cancer-diseased parents, both loss-oriented and restoration-oriented processes should equally be recognized and encouraged.


Subject(s)
Adaptation, Psychological , Anticipation, Psychological , Child of Impaired Parents/psychology , Grief , Neoplasms/psychology , Adolescent , Attitude to Death , Female , Humans , Interview, Psychological , Male , Social Support , Young Adult
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