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Major geodynamic processes, including mantle convection and plate tectonics, govern the exchange of mass between Earth's interior and its surface. These processes drive mass-transfer mechanisms such as partial melting and crustal recycling, which have generated a lithologically and compositionally heterogeneous mantle over time. Ocean island basalts (OIB) directly sample these heterogeneities, making them excellent tools to constrain the mantle's dynamic geochemical evolution. In this study, we probe the connection between crustal recycling, mantle mineralogy, and partial melting using the stable Ca isotope compositions of OIB, ultimately contextualizing their Ca isotope variability using conventional mantle "endmember" components including DMM, HIMU, EM-1, and EM-2. Using the state-of-the-art Nu Sapphire collision cell MC-ICP-MS, we measured the Ca isotope compositions of 27 well-characterized OIB samples from 11 different ocean island groups. By supplementing our new data with additional high-precision Ca isotope measurements from the literature, we create an expanded dataset consisting of 15 ocean islands, facilitating a global-scale investigation of Ca isotope variability among hotspots. Our findings reveal that island-averaged Ca isotope compositions form two distinct groups on the basis of their radiogenic isotope compositions. The first group, consisting of OIB with un-enriched radiogenic isotope compositions (non-EM-type), exhibits robust negative correlations with both lithospheric thickness and primitive TiO 2 contents, providing compelling evidence that Ca isotopes are sensitive to the degree of partial melting (F) as well as to the effects of crustal recycling. This joint signal appears to trace the process of decompression melting beneath oceanic lithosphere of variable thickness, as recycled lithologies rich in garnet and pyroxene (i.e., pyroxenites)—which generate large solid-melt Ca isotope fractionations—disproportionally control the Ca isotope composition of the final aggregate melt when F is limited by thick overlying lithosphere. In contrast, the island-averaged Ca isotope compositions of OIB with enriched radiogenic isotope compositions (EM-type) form a distinctly light negative correlation with primitive TiO 2 contents without exhibiting a relationship with lithospheric thickness. In addition to lithology-dependent partial melting effects, the Ca isotope compositions of EM-type OIB appear to be sensitive to the compositional effects of crustal recycling, which may explain their decoupling from the physical controls of partial melting. Calcium isotopes show exceptional potential for elucidating the origin of both enriched and ultra-depleted mantle sources, emphasizing the need to prioritize localities with these signatures in future studies. [ABSTRACT FROM AUTHOR]

Characterizing the K-isotope compositions of marine sediments is a necessary step to using this novel isotope system to investigate K cycling both in the ocean system and in subduction zones. Here we report data for 70+ samples in order to characterize the K-isotope compositions of deep-sea sediments for two drill sites in the western Pacific: (1) IODP Site C0011 adjacent to the Nankai Trough and Southwest Japan arc and (2) Site 1149 adjacent to the Izu-Bonin trench and arc. Variation in δ 41 K at both sites is mostly subtle, reflecting a consistently strong contribution of K from sources that have δ 41 K similar to the upper continental crust (UCC). Yet, in detail, the mean δ 41 K at both sites is about 0.05–0.10 ‰ lower than a recently proposed best estimate for UCC ( δ 41 K = −0.44 ‰). We infer that the slightly low mean δ 41 K values relative to UCC are likely caused by secondary processes acting on the volcanogenic component of the sediments, though chemical weathering of (non-volcanogenic) terrigenous materials may also play a role. We measured a very low δ 41 K value (−1.33 ± 0.04 ‰) for one discrete ash layer at Site C0011, so volcanoclastic materials may lower the δ 41 K values of the bulk sediments, despite only accounting for a small fraction of the K in the sediments. Correlations between δ 41 K , Cr/Al, and K/Al in the upper sediments of Site 1149 were used to investigate mixing between volcanic ash and terrigenous materials. This approach indicates that mixing of isotopically light volcanic ash (with δ 41 K about −0.75 ‰) and terrigenous materials (about −0.46 ‰) can account for the observed variation in δ 41 K values in these sediments. In addition, we observe that at Site C0011 K isotopes exhibit a shift (by ~0.08 ‰) at ~250 m below the seafloor from UCC-like compositions in the upper sediments to slightly lighter compositions in the lower sediments. This shift in δ 41 K coincides with an abrupt change in certain physical properties (porosity and cementation) of the sediments that may relate to the extent of weathering/degradation of the dispersed volcaniclastics, with more extensively weathered materials present in the lower sediments. Finally, we find evidence for variable admixture of a high δ 41 K silicic volcanic ash in the lowermost sediments at Site C0011, supporting the view that heterogeneous volcaniclastics can give rise to significant δ 41 K variations in marine sediments. [ABSTRACT FROM AUTHOR]

Many cancer survivors report cognitive problems following diagnosis and treatment. However, the clinical significance of patient-reported cognitive symptoms early in survivorship can be unclear. We used a machine learning approach to determine the association of persistent self-reported cognitive symptoms two years after diagnosis and neurocognitive test performance in a prospective cohort of older breast cancer survivors. We enrolled breast cancer survivors with non-metastatic disease (n = 435) and age- and education-matched non-cancer controls (n = 441) between August 2010 and December 2017 and followed until January 2020; we excluded women with neurological disease and all women passed a cognitive screen at enrollment. Women completed the FACT-Cog Perceived Cognitive Impairment (PCI) scale and neurocognitive tests of attention, processing speed, executive function, learning, memory and visuospatial ability, and timed activities of daily living assessments at enrollment (pre-systemic treatment) and annually to 24 months, for a total of 59 individual neurocognitive measures. We defined persistent self-reported cognitive decline as clinically meaningful decline (3.7+ points) on the PCI scale from enrollment to twelve months with persistence to 24 months. Analysis used four machine learning models based on data for change scores (baseline to twelve months) on the 59 neurocognitive measures and measures of depression, anxiety, and fatigue to determine a set of variables that distinguished the 24-month persistent cognitive decline group from non-cancer controls or from survivors without decline. The sample of survivors and controls ranged in age from were ages 60–89. Thirty-three percent of survivors had self-reported cognitive decline at twelve months and two-thirds continued to have persistent decline to 24 months (n = 60). Least Absolute Shrinkage and Selection Operator (LASSO) models distinguished survivors with persistent self-reported declines from controls (AUC = 0.736) and survivors without decline (n = 147; AUC = 0.744). The variables that separated groups were predominantly neurocognitive test performance change scores, including declines in list learning, verbal fluency, and attention measures. Machine learning may be useful to further our understanding of cancer-related cognitive decline. Our results suggest that persistent self-reported cognitive problems among older women with breast cancer are associated with a constellation of mild neurocognitive changes warranting clinical attention. [ABSTRACT FROM AUTHOR]

Summary Protected areas may impose local welfare costs through the enforcement of use restrictions. Predicting their welfare impacts before their establishment could help with the design of compensation schemes. Discrete choice experiments (DCEs) are increasingly used for ex ante evaluations but their validity is largely untested in low-income settings. Using a case study of a new REDD+ (Reducing Emissions from Deforestation and forest Degradation) project in eastern Madagascar, we explore the validity of DCEs in two ways: (i) whether the estimates of welfare costs derived from DCE are affected by respondents’ prior experience of conservation (ii) whether DCE results have high theoretical and content validity. We surveyed households who have varying degrees of experience of restrictions to swidden agriculture. We also qualitatively debriefed a sub-sample of respondents to better understand their thought processes. Latent class analysis shows that DCE outcomes vary with conservation experience. Households more experienced with forest protection are less willing to trade-off rights to clear forest for swidden agriculture with any compensatory interventions whereas less experienced households highly favor support for alternative agricultural techniques and a secure right to clear one hectare of forest. Although the results show apparent non-attendance to some attributes (e.g., cash payments), qualitative debriefings suggest that respondents infact do expect relatively low or no utility from the given attributes and hence have theoretically valid preferences. Similarly, the DCE has generally high content validity. Although DCE can elicit current preferences in this context, using ex ante DCE to estimate the welfare costs of such a long-term intervention requires caution. We conclude that it is difficult to robustly estimate compensation in advance of an intervention, there is therefore a need to rethink conservation approaches, and the feasibility of achieving fair compensations for conservation-imposed restrictions. [ABSTRACT FROM AUTHOR]

We report mass-dependent and mass-independent Ca isotopic variations in nine chondrites from three groups: carbonaceous, ordinary and enstatite chondrites. There is about 0.25‰ per amu, i.e., ∼1‰ in 44 Ca/ 40 Ca, variation in chondrites: carbonaceous chondrites have the lightest Ca isotopes, enstatite chondrites have modeled bulk Earth like Ca isotopes, and ordinary chondrites are in between. The correlations between mass-dependent Ca isotopic variation and chemical variations in chondrites may reflect variable contributions from different endmembers, including refractory inclusions, in different chondrite groups. In detail, enstatite chondrites and the Earth share similar isotopic characteristics, but are very different in chemical compositions. At the ±1 and ±2 ε-unit levels, respectively, there is no measurable 40 Ca or 43 Ca anomaly in bulk chondrites. Carbonaceous chondrites show several ε-units of 48 Ca excess. That is, Ca exhibits both mass-dependent and mass-independent isotopic variations in chondrites, similar to O isotopes. The 48 Ca anomaly in bulk chondrites is positively correlated with 50 Ti anomaly, but does not form simple correlation with 54 Cr anomaly, implying multiple supernova sources for these neutron-rich isotopes in the Solar System. Finally, all meteorites with negative Δ 17 O have either 48 Ca deficits (differentiated meteorites) or 48 Ca excess (carbonaceous chondrites), implying that the Sun with a very negative Δ 17 O is probably also characterized by 48 Ca anomaly compared to the Earth. CAIs cannot be taken as representative of the initial isotopic compositions of refractory elements like Ca for the Earth–Moon system. [ABSTRACT FROM AUTHOR]

This individual patient data meta-analysis aimed to evaluate the effects of exercise on quality of life (QoL) and physical function (PF) in patients with cancer, and to identify moderator effects of demographic (age, sex, marital status, education), clinical (body mass index, cancer type, presence of metastasis), intervention-related (intervention timing, delivery mode and duration, and type of control group), and exercise-related (exercise frequency, intensity, type, time) characteristics. Relevant published and unpublished studies were identified in September 2012 via PubMed, EMBASE, PsycINFO, and CINAHL, reference checking and personal communications. Principle investigators of all 69 eligible trials were requested to share IPD from their study. IPD from 34 randomised controlled trials (n=4519 patients) that evaluated the effects of exercise compared to a usual care, wait-list or attention control group on QoL and PF in adult patients with cancer were retrieved and pooled. Linear mixed-effect models were used to evaluate the effects of the exercise on post-intervention outcome values (z-score) adjusting for baseline values. Moderator effects were studies by testing interactions. Exercise significantly improved QoL (β=0.15, 95%CI=0.10;0.20) and PF (β=0.18, 95%CI=0.13;0.23). The effects were not moderated by demographic, clinical or exercise characteristics. Effects on QoL (βdifference_in_effect=0.13, 95%CI=0.03;0.22) and PF (βdifference_in_effect=0.10, 95%CI=0.01;0.20) were significantly larger for supervised than unsupervised interventions. In conclusion, exercise, and particularly supervised exercise, effectively improves QoL and PF in patients with cancer with different demographic and clinical characteristics during and following treatment. Although effect sizes are small, there is consistent empirical evidence to support implementation of exercise as part of cancer care. [ABSTRACT FROM AUTHOR]

Objective Chemotherapy is less often prescribed in older individuals due to concerns about post-treatment morbidity and quality of life. We evaluated the physical performance of breast cancer survivors treated with and without adjuvant chemotherapy. Materials and Methods We conducted a case–control study in 56 estrogen receptor positive breast cancer survivors (BCS) on adjuvant aromatase inhibitors 1–2 years after definitive surgery. Cases had received adjuvant chemotherapy (n = 27; age 70.5 ± 3.6 years) versus age-matched controls who had not (n = 29; age 70.0 ± 4.3 years). Measures of grip strength, physical activity and performance, walking speed, fatigue, and self-reported physical function were collected. Biological correlates of inflammation, frailty and markers of DNA and RNA oxidation were compared. Results Grip strength (controls: 21 ± 7.4 vs. cases: 29.7 ± 5.0 kg, p = 0.20), physical activity (5403 ± 3204 vs. 6801 ± 9320 steps/day, p = 0.45), physical performance (short physical performance battery score: 10.1 ± 1.8 vs. 10.4 ± 1.1, p = 0.52) and long-distance walking speed (1.2 ± 0.21 vs. 1.3 ± 0.41 m/s, p = 0.17) were similar between the two groups. Self-reported physical function was marginally lower in cases than controls (controls: 72 ± 24 vs. cases: 57 ± 34 AU, p = 0.07). Fatigue disruptiveness was not different between groups (controls: 11.1 ± 13.0 vs. cases: 15.7 ± 16.2 AU, p = 0.24). Similarly, the inflammation, oxidation, and frailty markers did not present a significant difference between groups, except for vitamin D levels (p = 0.04). Conclusion Older women who received chemotherapy reported having slightly lower physical function, but a similar physical performance compared to women who did not. These data suggest that older BCS treated with chemotherapy recover to an extent similar to survivors who only received hormonal therapy. [ABSTRACT FROM AUTHOR]

We report a method for high-precision potassium isotope measurements that improves by an order of magnitude the precision compared to previous methods. The purification of K is achieved through ion exchange chromatography on AG50W-X8 cation exchange resins. The 41 K/ 39 K ratios are analyzed with a GV Instruments IsoProbe P Multiple-Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS) equipped with a hexapole collision gas cell. With this technique, the argon-hydride interferences as well as the large 40 Ar + peak from the Ar-plasma are eliminated. The 41 K/ 39 K ratios can thus be obtained with a precision of 0.05 per mil. The precision and accuracy of this method is validated with gravimetrically determined 41 K or 39 K enriched standards. New precise K isotopic compositions of three terrestrial basalts (BCR-2, BHVO-1 and a MORB) are also reported. These basalts have indistinguishable K isotopic compositions and are used to define a reference value of −0.479 ± 0.027 per mil for the 41 K/ 39 K ratio of the Bulk Silicate Earth (BSE) relative to a Merck Suprapur potassium nitrate standard. Seawater and sylvites from evaporite deposits have similar 41 K/ 39 K ratios, but higher by up to 0.227 per mil compared to the Merck Suprapur standard. Other commercially available K-salts/solutions also have 41 K/ 39 K ratios similar to the Merck standard, while a SPEX K-chloride was higher by 0.384 per mil. This shows that K isotope variations will be useful as a tracer in low-temperature geochemistry processes. [ABSTRACT FROM AUTHOR]

Transmission lines are critical infrastructures, but frequently contested especially at the local level, by local communities. The role of public engagement in processes pertaining to specific transmission line projects is an under-researched, yet important topic that this paper seeks to discuss by investigating how inhabitants perceive these processes and to what extent they find the processes just and fair. This paper addresses the participatory aspects of the planning process, as perceived by the local inhabitants in four Norway and UK cases, by using a qualitative comparative case study design. We further analyse this issue through frameworks of public engagement and procedural justice. In both countries public engagement is largely characterized by perceptions of insufficient information, and insufficient influence on the process. In sum, the findings indicate that the informants generally perceive the opportunities for involvement as insufficient and unjust. The findings are quite similar across all cases and both countries. Local inhabitants represent diverse groups who often have different levels of knowledge, time and engagement to bring to the planning process. Their requests for improved processes thus underline the serious public engagement challenges that applicants and decision-makers face. [ABSTRACT FROM AUTHOR]

Objective To compare the incidence and severity of postoperative complications after oesophagectomy for carcinoma of the oesophagus and gastro-oesophageal junction (GOJ) after randomized accrual to neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT). Background Neoadjuvant therapy improves long-term survival after oesophagectomy. To date, evidence is insufficient to determine whether combined nCT, or nCRT alone, is the most beneficial. Methods Patients with carcinoma of the oesophagus or GOJ, resectable with a curative intention, were enrolled in this multicenter trial conducted at seven centres in Sweden and Norway. Study participants were randomized to nCT or nCRT followed by surgery with two-field lymphadenectomy. Three cycles of cisplatin/5-fluorouracil was administered in all patients, while 40 Gy of concomitant radiotherapy was administered in the nCRT group. Results Of the randomized 181 patients, 91 were assigned to nCT and 90 to nCRT. One-hundred-and-fifty-five patients, 78 nCT and 77 nCRT, underwent resection. There was no statistically significant difference between the groups in the incidence of surgical or nonsurgical complications (P-value = 0.69 and 0.13, respectively). There was no 30-day mortality, while the 90-day mortality was 3% (2/78) in the nCT group and 6% (5/77) in the nCRT group (P = 0.24). The median Clavien-Dindo complication severity grade was significantly higher in the nCRT group (P = 0.001). Conclusion There was no significant difference in the incidence of complications between patients randomized to nCT and nCRT. However, complications were significantly more severe after nCRT. Registration trial database The trial was registered in the Clinical Trials Database (registration number NCT01362127 ). [ABSTRACT FROM AUTHOR]

Background: The definition of Chronic Fatigue Syndrome (CFS) overlaps with definitions of insomnia, but there is limited knowledge about the role of insomnia in the treatment of chronic fatigue.Aims: To test if improvement of insomnia during treatment of chronic fatigue was associated with improved outcomes on 1) fatigue and 2) cortisol recovery span during a standardized stress exposure.Methods: Patients (n = 122) with chronic fatigue received a 3.5-week inpatient return-to-work rehabilitation program based on Acceptance and Commitment Therapy, and had been on paid sick leave>8 weeks due their condition. A physician and a psychologist examined the patients, assessed medication use, and SCID-I diagnoses. Patients completed self-report questionnaires measuring fatigue, pain, depression, anxiety, and insomnia before and after treatment. A subgroup (n = 25) also completed the Trier Social Stress Test for Groups (TSST-G) before and after treatment. Seven cortisol samples were collected during each test and cortisol spans for the TSST-G were calculated.Results: A hierarchical regression analysis in nine steps showed that insomnia improvement predicted improvement in fatigue, independently of age, gender, improvement in pain intensity, depression and anxiety. A second hierarchical regression analysis showed that improvement in insomnia significantly predicted the cortisol recovery span after the TSST-G independently of improvement in fatigue.Conclusion: Improvement in insomnia severity had a significant impact on both improvement in fatigue and the ability to recover from a stressful situation. Insomnia severity may be a maintaining factor in chronic fatigue and specifically targeting this in treatment could increase treatment response. [ABSTRACT FROM AUTHOR]

The current study examined the feasibility of an appearance-based dissonance induction approach for the modification of tanning and sunscreen use behaviors. Undergraduate female students were randomized to: a healthy lifestyle condition, an appearance-based dissonance condition, or an appearance-based psychoeducation condition. Reports of tanning and sunscreen use were collected immediately before and 1 month following intervention ( N = 225). Relative to the healthy lifestyle condition, participants in the dissonance condition reported a significant reduction in daily hours spent tanning. Additionally, sunscreen use on the body decreased significantly for the healthy lifestyle group, but did not change for the dissonance group. The psychoeducation condition did not differ from the healthy lifestyle condition on any measure. These findings should encourage additional research into the use of dissonance induction as an appearance-based strategy for promoting reductions in UV exposure. [ABSTRACT FROM AUTHOR]

Studies show that engaging patients in exercise and/or stress management techniques during hematopoietic cell transplantation (HCT) improves quality of life. The Blood and Marrow Transplant Clinical Trials Network tested the efficacy of training patients to engage in self-directed exercise and stress management during HCT. The study randomized 711 patients at 21 centers to receive 1 of 4 training interventions before HCT: a self-directed exercise program, a self-administered stress management program, both, or neither. Participants completed self-reported assessments at enrollment and up to 180 days after HCT. Randomization was stratified by center and transplant type. There were no differences in the primary endpoints of the Physical Component Summary and Mental Component Summary scales of the Medical Outcomes Study Short Form 36 at day +100 among the groups, based on an intention-to-treat analysis. There also were no differences in overall survival, days of hospitalization through day +100 post-HCT, or in other patient-reported outcomes, including treatment-related distress, sleep quality, pain, and nausea. Patients randomized to training in stress management reported more use of those techniques, but patients randomized to training in exercise did not report more physical activity. Although other studies have reported efficacy of more intensive interventions, brief training in an easy-to-disseminate format for either self-directed exercise or stress management was not effective in our trial. [ABSTRACT FROM AUTHOR]

Abstract: We report Si isotopic data on a suite of terrestrial mantle-derived samples, meteorites and a lunar sample. Our data on co-existing mantle minerals, peridotites and basalts demonstrate lack of any resolvable high temperature fractionation during igneous processes. We show that the δ30Si of the bulk silicate Earth (BSE) is identical, within analytical uncertainties, to carbonaceous and ordinary chondrites (CHUR). Based on our data the difference between δ30SiBSE and δ30SiCHUR is 0.035±0.035. Whole-rock differentiated meteorites from different parent bodies (Mars, Vesta) and a lunar breccia sample also show similar δ30Si suggesting broad-scale Si isotope homogeneity in the inner Solar System with an average δ29Si=−0.20±0.01 and δ30Si=−0.39±0.02 relative to the NBS28 Si isotope standard. A difference between δ30SiBSE and δ30SiCHUR of 0.035, as observed in our study, translates to less than 1.67wt.% Si in the core considering a continuous accretion model whereas estimates using a batch model are even lower. Within uncertainties (±0.035‰) in the δ30Si difference between the BSE and CHUR, a maximum of 3.84wt.% Si could be present in the Earth’s core whereas at δ30SiBSE–δ30SiCHUR =0, there is no requirement of Si in the Earth’s core. Such low Si in the core necessitates the presence of other light elements in the core to explain its density deficit. Our data also places constraints on the oxidation state of the Earth’s mantle during core segregation. The uncertainties in estimating the concentration of oxidized Fe in the mantle during the first 90% of accretion arise from uncertainties in the estimates of the equilibrium partition coefficient of silicon between metal and silicate at conditions relevant to core formation. For δ30SiBSE–δ30SiCHUR =0.035±0.035, the concentration of oxidized Fe in the mantle during the first 90% of accretion could be as low as ∼1%. However, at δ30SiBSE–δ30SiCHUR =0, the Si isotope data do not require any change in the mantle concentration of oxidized Fe during accretion from the present day value of 6.26%. [Copyright &y& Elsevier]

Abstract: The forsterite-bearing Type B (FoB) CAI SJ101 consists of three major structural units: (1) light patches of sector-zoned, poikilitic Al-rich clinopyroxene (Cpx) with numerous inclusions of small spinel grains and aggregates and subordinate amounts of Mg-rich melilite (Mel) and anorthite (An) (Sp–Cpx lithology), (2) dark sinuous bands of Al-rich clinopyroxene with large (up to ∼300×60μm) poikilitically enclosed euhedral forsterite (Fo) crystals (Fo–Cpx lithology), and (3) the external Cpx–Sp–An rim overlying the entire inclusion. The two major lithologies are always separated by a transition zone of clinopyroxene poikilitically enclosing both forsterite and spinel. The patches of the Sp–Cpx lithology exhibit significant textural and mineralogical variability that is size-dependent. Small patches typically consist of Cpx and spinel with minor remnants of melilite and/or its alteration products. Large patches contain Mel–An-rich cores with either equigranular–ophitic–subophitic or ‘lacy’ textures reminiscent of those in Types B or C CAIs, respectively. All silicates poikilitically enclose numerous spinel grains of identical habit. Both melilite and anorthite gradually disappear toward the boundary with the Fo–Cpx lithology. Neither the evaporation mantle of Al-rich melilite typical of other FoBs nor the Wark–Lovering rim is present. Secondary minerals include grossular, monticellite, magnetite, and a few grains of wollastonite, andradite, and nepheline. Being a rather typical FoB mineralogically and chemically, texturally SJ101 differs from other FoBs in displaying the nearly complete segregation of forsterite from spinel which occur only in the Fo–Cpx and Sp–Cpx lithologies, respectively. The complex, convoluted internal structure of SJ101 suggests that the coarse-grained Sp–An–Mel–Cpx cores and Fo–Cpx lithology represent the precursor materials of FoBs, proto-CAIs and Fo-rich accretionary rims. While the inferred chemistry and mineralogy of the Fo-rich rims are fairly typical, the high Åk content in SJ101 melilite (78.7–82.3mol.%) implies that the SJ101 proto-CAIs represent a new type of CAIs that has not been sampled before. This type of CAIs might have formed by remelting of spinel-rich condensates. The Group II REE pattern, slightly negative δ29Si and δ25Mg values, and nearly solar ratios of the major elements in the bulk SJ101 suggest that its precursors, proto-CAIs and Fo-rich rims, could have formed by a non-equilibrium condensation in a closed system of solar composition somewhat depleted in a super-refractory evaporation residue. The proposed formation scenario of SJ101 invokes a non-steady cooling and condensation of the nebular gas interrupted by at least two distinct melting episodes required to account for the igneous textures of the Mel–An–Cpx-rich cores (proto-CAIs) and the Fo–Cpx lithology. [Copyright &y& Elsevier]

• Isotopically heavy K documented in Izu arc front. • Systematic shift to lighter K-isotope ratios in Izu rear arc. • Heavy K may reflect isotopic fractionation in association with slab dehydration. • Across-arc shift may reflect progressive depletion of slab in heavy K. • Potassium-isotope variations in arc lavas may be sensitive tracer of slab processes. In subduction zones, fluids rise from the slab to the mantle, causing metasomatism and flux melting of the mantle to produce arc magmas. The transfer of material from slab to mantle and, in turn, to arc crust is an important control on the long-term chemical evolution of the mantle and continental crust. In this study, we investigate the transport of K in subduction zones by exploring the systematics of K stable-isotope variations in lavas of the Izu arc. We find that the Izu lavas have isotopically heavy K relative to estimates for midocean ridge basalt (MORB)-source upper mantle. Moreover, the δ 41 K values of the lavas are clearly heavier than those of subducting sediments and are probably heavier than subducting altered ocean crust. An across-arc decrease in δ 41 K values is apparent. Arc-front lavas are heavier than the mantle by about 0.22‰ (median), whereas rear-arc lavas are heavier by only about 0.08‰ (median). The heavy K-isotope compositions of the arc lavas may arise from isotopic fractionation during slab dehydration, where light K is preferentially retained in phases such as phengite in the slab. The across-arc decrease in δ 41 K values may be due to progressive breakdown of these phases, and to associated depletion of the slab in heavy K. Variations in the relative contributions of different source materials—igneous ocean crust, sediment, and mantle peridotite—may also play a role. In particular, we explore a possibility, motivated by radiogenic-isotope studies, that the slab signal in K isotopes may be attenuated in the rear arc as a result of extensive fluid-mantle interaction. If K isotopes do track slab dehydration, then K isotopes provide insight into the transfer of K and similarly mobile elements out of the slab and into the upper mantle and arc crust. Lastly, we observe extreme isotopic variations in some of the lavas, which we interpret to result from crustal-level or Earth-surface processes that affect only a subset of the lavas. [ABSTRACT FROM AUTHOR]

Abstract: Breast self-examinations (BSE) and skin self-examinations (SSE) represent cost-effective and time-efficient approaches to cancer detection. Given their utility, it is important to determine who is likely to perform these behaviors regularly and why. Because BSE and SSE require close examination of one''s body, women who are less satisfied and less comfortable with their bodies may perform these behaviors less often. This study sought to determine if a relationship exists between body image and BSE and SSE behaviors and intentions. Ninety-three women completed measures assessing body image, past performance of and future intentions to perform BSE and SSE. Results indicated that body image was related to past performance of SSE. Having greater body-areas satisfaction and more favorable global evaluations of appearance were related to having performed SSE more frequently in the past year. Future research should further examine this relationship utilizing longitudinal designs and more diverse populations. [Copyright &y& Elsevier]

Abstract: The Fatigue Symptom Inventory has been used extensively to assess and measure fatigue in a number of clinical populations. The purpose of the present study was to further establish its utility by examining its operating characteristics and determining the optimal cutoff score for identifying clinically meaningful fatigue. The MOS 36-Item Short Form Vitality scale, a measure widely used to identify individuals with significant fatigue-related disability, was used to determine the sensitivity and specificity of the Fatigue Symptom Inventory. Results indicate that a score of 3 or greater on those items assessing fatigue in the past week is the optimal cutoff score for identifying clinically meaningful fatigue. Individuals who scored at or above the cutoff also reported significantly greater fatigue interference, more days of fatigue on average, and fatigue a greater proportion of each day in the past week. Findings suggest that the Fatigue Symptom Inventory can be used to discriminate effectively between individuals with and without clinically meaningful fatigue. [Copyright &y& Elsevier]

Abstract: Aims: To evaluate possible differences in effect on recurrence-free survival (RFS) and overall survival (OS) in node positive postmenopausal breast cancer patients receiving Tamoxifen or cyclic Tam and Megestrol acetate as adjuvant treatment. Methods: Between 1989 and 1994, 489 patients with pT1–2pN+ hormone receptor positive or unknown tumours were included in a randomized national multicenter study to receive either Tam alone or cyclic Tam (8 weeks) and MA (8 weeks) for 2 years. Final follow-up was completed as of June 2002. Time from start of treatment to first recurrence and novel primary breast tumour, overall survival and cancer specific survival were estimated. Results: No differences in RFS, OS or cancer specific survival were observed between the two treatment groups. Conclusions: Adjuvant treatment used as standard Tam alone, compared to Tam and MA, as employed in this group of patients gave similar outcomes. Side effects that led to cessation of study medication were observed in both arms. [Copyright &y& Elsevier]

Abstract: The α-conotoxin family is comprised of peptides that share the following arrangement of cysteine residues in the primary amino acid sequence: –CC–C–C–, where each dash represents a variable number of amino acids. The number of amino acids between cysteine residues has been used to group the α-conotoxins into distinct subfamilies. These subfamilies include the α4/7-, α4/3- and α3/5-conotoxins, so named for the number of amino acids between 2nd/3rd and 3rd/4th cysteine residues, respectively. The α3/5-conotoxins antagonize vertebrate-muscle nicotinic acetylcholine receptors (nAChRs), while the α4/7- and α4/3-conotoxins primarily inhibit vertebrate neuronal nAChRs. To date, these three subfamilies are the most extensively characterized of the α-conotoxin family. Here we report the purification and characterization of an unusual α4/4-conotoxin, α-conotoxin PIB (α-PIB), from the venom of Conus purpurascens, with the following amino-acid sequence: ZSOGCCWNPACVKNRC (Z=pyroglutamate, O=hydroxyproline). This peptide demonstrates high affinity inhibition of vertebrate-muscle nAChRs, and paralytic effects when injected in vivo. Testing of α-PIB against other receptors indicated that the inhibitory effect is specific for skeletal muscle nAChRs. α-PIB shares the key biochemical and pharmacological characteristics of the α-conotoxin family. [Copyright &y& Elsevier]

Objectives: To review the evidence for considering fatigue, depression, and insomnia as a symptom cluster in cancer. Data Sources: Empirical studies, clinical articles, and review articles. Conclusion: The single- and multi-symptom measurement approaches are of limited usefulness in distinguishing fatigue, depression, and insomnia. Studies in which these symptoms have been measured concurrently in patients with cancer yield consistent evidence of high positive correlations. Results do not appear to be solely a function of overlap in measurement approaches. Implications for Nursing Practice: Successful management of fatigue, depression, and insomnia in cancer patients are likely to combine pharmacologic and nonpharmacologic therapies. [Copyright &y& Elsevier]

Background: Targeting higher risk individuals, such as melanoma patients'' first-degree relatives, may be more efficient than mass skin cancer screening. Objective: Our aim was to examine prevalence and predictors of total cutaneous examination in first-degree relatives. Methods: Ninety-five first-degree relatives completed questionnaires assessing demographic and risk characteristics, perceived risk, perceived severity, self-efficacy, response efficacy, and total skin examination. Fourteen months later, first-degree relatives were asked if they had obtained a total skin examination during follow-up. Results: At baseline, 47% reported at least one total cutaneous examination and 27% had a health care provider recommendation for total skin examination. At follow-up, 37% had obtained a total skin examination. Baseline and follow-up total cutaneous examination was associated with more risk factors, higher education, provider recommendation, and greater perceived risk and severity. In multivariate analyses, provider recommendation and college education predicted follow-up total skin examination. Limitations: Data were self reported. Knowledge, health-care access, and follow-up provider recommendation were not assessed. Conclusion: Physicians and other providers may be influential in promoting total cutaneous examination in first-degree relatives. [Copyright &y& Elsevier]

Abstract: The current study evaluated a newly developed self-report measure of cognitive complaints with cancer patients, the Functional Assessment of Cancer Therapy Cognitive Scale (FACT-Cog). Six or 12 months following hematopoetic stem cell transplantation, participants completed a psychosocial assessment that included the FACT-Cog and a neuropsychological assessment. Using a criterion of two or more times a week, an average of 12 of a total of 50 items were endorsed as complaints on the FACT-Cog. FACT-Cog total, domain, and subscale scores were significantly correlated with measures of depression, fatigue, anxiety, and physical and mental well-being. FACT-Cog scores, with the exception of one subscale, Other People Noticed Deficits, were not significantly correlated with cognitive performance. In general, the FACT-Cog and a commonly used measure of cognitive complaints (European Organization for Research and Treatment of Cancer-Quality of Life Questionnaire-C30 Cognitive Functioning Scale) demonstrated similar psychometric properties. However, the FACT-Cog assesses broader aspects of cognitive complaints, thereby providing greater information about the types of cognitive complaints patients are experiencing. [Copyright &y& Elsevier]

Abstract: Motives for UV exposure have been shown to be related to appearance concerns, yet little research has examined specific tan appearance attitudes. Given this lacuna, Study 1 involved the identification of six factors among college female tanners: general attractiveness, media influence, family/friends influence, physical fitness appearance, acne reasons, and skin aging concerns. In Study 2, a separate sample of college female tanners were used to validate a higher order factor model, which demonstrated acceptable fit. Additionally, the factors converged in the expected directions, with the general attractiveness and skin aging concerns being the best correlate of UV exposure and sun-protection intentions. The relevance of these findings to skin cancer prevention is discussed. [Copyright &y& Elsevier]