The UCLA Cosmochemistry Database.

The UCLA Cosmochemistry Database was initiated as part of a data-rescue and -storage project aimed at archiving a variety of cosmochemical data acquired at University of California, Los Angeles (UCLA). The data collection includes elemental compositions of extraterrestrial materials analyzed by UCLA cosmochemists over the last five decades. The analytical techniques include atomic absorption spectrometry (AAS) and neutron activation analysis (NAA) at UCLA. The data collection is stored on the Astromaterials Data System (Astromat). We provide both interactive tables and downloadable datasheets for users to access all data. The UCLA Cosmochemistry Database archives cosmochemical data that are essential tools for increasing our understanding of the nature and origin of extraterrestrial materials. Future studies can reference the data collection in the examination, analysis, and classification of newly acquired extraterrestrial samples.

Formate overflow drives toxic folate trapping in MTHFD1 inhibited cancer cells.

Cancer cells fuel their increased need for nucleotide supply by upregulating one-carbon (1C) metabolism, including the enzymes methylenetetrahydrofolate dehydrogenase-cyclohydrolase 1 and 2 (MTHFD1 and MTHFD2). TH9619 is a potent inhibitor of dehydrogenase and cyclohydrolase activities in both MTHFD1 and MTHFD2, and selectively kills cancer cells. Here, we reveal that, in cells, TH9619 targets nuclear MTHFD2 but does not inhibit mitochondrial MTHFD2. Hence, overflow of formate from mitochondria continues in the presence of TH9619. TH9619 inhibits the activity of MTHFD1 occurring downstream of mitochondrial formate release, leading to the accumulation of 10-formyl-tetrahydrofolate, which we term a 'folate trap'. This results in thymidylate depletion and death of MTHFD2-expressing cancer cells. This previously uncharacterized folate trapping mechanism is exacerbated by physiological hypoxanthine levels that block the de novo purine synthesis pathway, and additionally prevent 10-formyl-tetrahydrofolate consumption for purine synthesis. The folate trapping mechanism described here for TH9619 differs from other MTHFD1/2 inhibitors and antifolates. Thus, our findings uncover an approach to attack cancer and reveal a regulatory mechanism in 1C metabolism.

Direct visualization of Rashba-split bands and spin/orbital-charge interconversion at KTaO3 interfaces.

Rashba interfaces have emerged as promising platforms for spin-charge interconversion through the direct and inverse Edelstein effects. Notably, oxide-based two-dimensional electron gases display a large and gate-tunable conversion efficiency, as determined by transport measurements. However, a direct visualization of the Rashba-split bands in oxide two-dimensional electron gases is lacking, which hampers an advanced understanding of their rich spin-orbit physics. Here, we investigate KTaO3 two-dimensional electron gases and evidence their Rashba-split bands using angle resolved photoemission spectroscopy. Fitting the bands with a tight-binding Hamiltonian, we extract the effective Rashba coefficient and bring insight into the complex multiorbital nature of the band structure. Our calculations reveal unconventional spin and orbital textures, showing compensation effects from quasi-degenerate band pairs which strongly depend on in-plane anisotropy. We compute the band-resolved spin and orbital Edelstein effects, and predict interconversion efficiencies exceeding those of other oxide two-dimensional electron gases. Finally, we suggest design rules for Rashba systems to optimize spin-charge interconversion performance.

DGAT1 activity synchronises with mitophagy to protect cells from metabolic rewiring by iron depletion.

Mitophagy removes defective mitochondria via lysosomal elimination. Increased mitophagy coincides with metabolic reprogramming, yet it remains unknown whether mitophagy is a cause or consequence of such state changes. The signalling pathways that integrate with mitophagy to sustain cell and tissue integrity also remain poorly defined. We performed temporal metabolomics on mammalian cells treated with deferiprone, a therapeutic iron chelator that stimulates PINK1/PARKIN-independent mitophagy. Iron depletion profoundly rewired the metabolome, hallmarked by remodelling of lipid metabolism within minutes of treatment. DGAT1-dependent lipid droplet biosynthesis occurred several hours before mitochondrial clearance, with lipid droplets bordering mitochondria upon iron chelation. We demonstrate that DGAT1 inhibition restricts mitophagy in vitro, with impaired lysosomal homeostasis and cell viability. Importantly, genetic depletion of DGAT1 in vivo significantly impaired neuronal mitophagy and locomotor function in Drosophila. Our data define iron depletion as a potent signal that rapidly reshapes metabolism and establishes an unexpected synergy between lipid homeostasis and mitophagy that safeguards cell and tissue integrity.

Gate-tuneable and chirality-dependent charge-to-spin conversion in tellurium nanowires.

Chiral materials are an ideal playground for exploring the relation between symmetry, relativistic effects and electronic transport. For instance, chiral organic molecules have been intensively studied to electrically generate spin-polarized currents in the last decade, but their poor electronic conductivity limits their potential for applications. Conversely, chiral inorganic materials such as tellurium have excellent electrical conductivity, but their potential for enabling the electrical control of spin polarization in devices remains unclear. Here, we demonstrate the all-electrical generation, manipulation and detection of spin polarization in chiral single-crystalline tellurium nanowires. By recording a large (up to 7%) and chirality-dependent unidirectional magnetoresistance, we show that the orientation of the electrically generated spin polarization is determined by the nanowire handedness and uniquely follows the current direction, while its magnitude can be manipulated by an electrostatic gate. Our results pave the way for the development of magnet-free chirality-based spintronic devices.

Comparative structural analysis provides new insights into the function of R2-like ligand-binding oxidase.

R2-like ligand-binding oxidase (R2lox) is a ferritin-like protein that harbours a heterodinuclear manganese-iron active site. Although R2lox function is yet to be established, the enzyme binds a fatty acid ligand coordinating the metal centre and catalyses the formation of a tyrosine-valine ether cross-link in the protein scaffold upon O2 activation. Here, we characterized the ligands copurified with R2lox by mass spectrometry-based metabolomics. Moreover, we present the crystal structures of two new homologs of R2lox, from Saccharopolyspora erythraea and Sulfolobus acidocaldarius, at 1.38 Å and 2.26 Å resolution, respectively, providing the highest resolution structure for R2lox, as well as new insights into putative mechanisms regulating the function of the enzyme.

Unconventional Charge-Spin Conversion in Weyl-Semimetal WTe2.

An outstanding feature of topological quantum materials is their novel spin topology in the electronic band structures with an expected large charge-to-spin conversion efficiency. Here, a charge-current-induced spin polarization in the type-II Weyl semimetal candidate WTe2 and efficient spin injection and detection in a graphene channel up to room temperature are reported. Contrary to the conventional spin Hall and Rashba-Edelstein effects, the measurements indicate an unconventional charge-to-spin conversion in WTe2 , which is primarily forbidden by the crystal symmetry of the system. Such a large spin polarization can be possible in WTe2 due to a reduced crystal symmetry combined with its large spin Berry curvature, spin-orbit interaction with a novel spin-texture of the Fermi states. A robust and practical method is demonstrated for electrical creation and detection of such a spin polarization using both charge-to-spin conversion and its inverse phenomenon and utilized it for efficient spin injection and detection in the graphene channel up to room temperature. These findings open opportunities for utilizing topological Weyl materials as nonmagnetic spin sources in all-electrical van der Waals spintronic circuits and for low-power and high-performance nonvolatile spintronic technologies.

A metabolite roadmap of the wood-forming tissue in Populus tremula.

Wood, or secondary xylem, is the product of xylogenesis, a developmental process that begins with the proliferation of cambial derivatives and ends with mature xylem fibers and vessels with lignified secondary cell walls. Fully mature xylem has undergone a series of cellular processes, including cell division, cell expansion, secondary wall formation, lignification and programmed cell death. A complex network of interactions between transcriptional regulators and signal transduction pathways controls wood formation. However, the role of metabolites during this developmental process has not been comprehensively characterized. To evaluate the role of metabolites during wood formation, we performed a high spatial resolution metabolomics study of the wood-forming zone of Populus tremula, including laser dissected aspen ray and fiber cells. We show that metabolites show specific patterns within the wood-forming zone, following the differentiation process from cell division to cell death. The data from profiled laser dissected aspen ray and fiber cells suggests that these two cell types host distinctly different metabolic processes. Furthermore, by integrating previously published transcriptomic and proteomic profiles generated from the same trees, we provide an integrative picture of molecular processes, for example, deamination of phenylalanine during lignification is of critical importance for nitrogen metabolism during wood formation.

Lipid accumulation controls the balance between surface connection and scission of caveolae.

Caveolae are bulb-shaped invaginations of the plasma membrane (PM) that undergo scission and fusion at the cell surface and are enriched in specific lipids. However, the influence of lipid composition on caveolae surface stability is not well described or understood. Accordingly, we inserted specific lipids into the cell PM via membrane fusion and studied their acute effects on caveolae dynamics. We demonstrate that sphingomyelin stabilizes caveolae to the cell surface, whereas cholesterol and glycosphingolipids drive caveolae scission from the PM. Although all three lipids accumulated specifically in caveolae, cholesterol and sphingomyelin were actively sequestered, whereas glycosphingolipids diffused freely. The ATPase EHD2 restricts lipid diffusion and counteracts lipid-induced scission. We propose that specific lipid accumulation in caveolae generates an intrinsically unstable domain prone to scission if not restrained by EHD2 at the caveolae neck. This work provides a mechanistic link between caveolae and their ability to sense the PM lipid composition.

Mapping spin-charge conversion to the band structure in a topological oxide two-dimensional electron gas.

While spintronics has traditionally relied on ferromagnetic metals as spin generators and detectors, spin-orbitronics exploits the efficient spin-charge interconversion enabled by spin-orbit coupling in non-magnetic systems. Although the Rashba picture of split parabolic bands is often used to interpret such experiments, it fails to explain the largest conversion effects and their relationship with the electronic structure. Here, we demonstrate a very large spin-to-charge conversion effect in an interface-engineered, high-carrier-density SrTiO3 two-dimensional electron gas and map its gate dependence on the band structure. We show that the conversion process is amplified by enhanced Rashba-like splitting due to orbital mixing and in the vicinity of avoided band crossings with topologically non-trivial order. Our results indicate that oxide two-dimensional electron gases are strong candidates for spin-based information readout in new memory and transistor designs. Our results also emphasize the promise of topology as a new ingredient to expand the scope of complex oxides for spintronics.

A standardized protocol for comparable analysis of GSH/GSSG by UHPLC-ESI-MSMS for human plasma.

Variability in the levels of GSH and GSSG in plasma is suggested to derive from inadequate pre-processing methods. The aim of this study was to develop a protocol for comparable and reliable measurements of GSH/GSSG. Venous blood from 8 healthy individuals were collected and divided into 7 different pre-processing procedures. For three of the samples an extraction mixture was added after 0 (baseline), 4 and 8 min and for three of the samples the extraction mixture was added at different times during defrost. A worst case scenario where a sample was left in a cool box during 6 h was also included. The samples were analyzed with UHPLC-ESI-MSMS. A large difference in the levels of GSH and GSSG were identified and it was clearly associated with the sample handling procedures. A sample left untreated for 4 min will have significantly reduced amount of GSH. Stability tests showed that the level of GSH was reduced after 3 months in -80 °C.

Rebuilding research capacity in fragile states: the case of a Somali-Swedish global health initiative.

This paper presents an initiative to revive the previous Somali-Swedish Research Cooperation, which started in 1981 and was cut short by the civil war in Somalia. A programme focusing on research capacity building in the health sector is currently underway through the work of an alliance of three partner groups: six new Somali universities, five Swedish universities, and Somali diaspora professionals. Somali ownership is key to the sustainability of the programme, as is close collaboration with Somali health ministries. The programme aims to develop a model for working collaboratively across regions and cultural barriers within fragile states, with the goal of creating hope and energy. It is based on the conviction that health research has a key role in rebuilding national health services and trusted institutions.

Predictors of contraceptive use among female adolescents in Ghana.

Adolescent girls in Ghana still face a number of challenges accessing reproductive/sexual health services despite efforts to improve their accessibility. This paper explores the key socio-demographic factors associated with contraceptive use amongst adolescent girls in Ghana using the 2008 Ghana Demographic and Health Survey (GDHS). Data from the 2008 GDHS was analyzed. Socio-demographic variables were selected to assess their interaction with contraceptive use. Multivariable regression analyses were performed. Odds ratios and confidence intervals were computed. Place of residence and marital status were the most important predictors of contraceptive use among sexually active adolescents. Rural residents were less likely to use contraceptives compared to urban residents (OR 0.32, CI 0.12-0.84, p = 0.021) as well as married respondents compared to their unmarried peers (OR 0.27, 95% CI 0.11-0.67, p = 0.005). The accessibility of reproductive/sexual health services needs to be improved and promoted in rural areas and among married adolescent women.

OnPLS integration of transcriptomic, proteomic and metabolomic data shows multi-level oxidative stress responses in the cambium of transgenic hipI- superoxide dismutase Populus plants.

BACKGROUND: Reactive oxygen species (ROS) are involved in the regulation of diverse physiological processes in plants, including various biotic and abiotic stress responses. Thus, oxidative stress tolerance mechanisms in plants are complex, and diverse responses at multiple levels need to be characterized in order to understand them. Here we present system responses to oxidative stress in Populus by integrating data from analyses of the cambial region of wild-type controls and plants expressing high-isoelectric-point superoxide dismutase (hipI-SOD) transcripts in antisense orientation showing a higher production of superoxide. The cambium, a thin cell layer, generates cells that differentiate to form either phloem or xylem and is hypothesized to be a major reason for phenotypic perturbations in the transgenic plants. Data from multiple platforms including transcriptomics (microarray analysis), proteomics (UPLC/QTOF-MS), and metabolomics (GC-TOF/MS, UPLC/MS, and UHPLC-LTQ/MS) were integrated using the most recent development of orthogonal projections to latent structures called OnPLS. OnPLS is a symmetrical multi-block method that does not depend on the order of analysis when more than two blocks are analysed. Significantly affected genes, proteins and metabolites were then visualized in painted pathway diagrams. RESULTS: The main categories that appear to be significantly influenced in the transgenic plants were pathways related to redox regulation, carbon metabolism and protein degradation, e.g. the glycolysis and pentose phosphate pathways (PPP). The results provide system-level information on ROS metabolism and responses to oxidative stress, and indicate that some initial responses to oxidative stress may share common pathways. CONCLUSION: The proposed data evaluation strategy shows an efficient way of compiling complex, multi-platform datasets to obtain significant biological information.

Outpatients' perspectives on problems and needs related to female genital mutilation/cutting: a qualitative study from somaliland.

Aim. To explore female outpatients' perspectives on problems related to female genital mutilation/cutting (FGM/C) and their views on information, care, and counseling. Setting. An FGM/C support center at a maternity clinic in Hargeisa, Somaliland. Methods. A qualitative, descriptive study, using content analysis of seven semistructured interviews with female outpatients. Results. All participants had been ignorant of the etiology of their FGM/C-related complications and hesitant to seek care. All had undergone infibulation but did not wish the same for their daughters. In recent years they had learnt through religious leaders and media campaigns that infibulation was unapproved by Islam. A less severe FGM/C type, "Sunna," was more accepted; however, few could define what "Sunna" meant. Condemning and ridiculing attitudes against uncircumcised women prevailed in their community. Conclusions. New ideas and concepts related to FGM/C enter the common discourse in the Somali society while traditional norms and values still prevail. Religion was shown to have a strong impact on FGM/C practices and beliefs. Interventions aiming to raise awareness of health consequences of all types of FGM/C, as well as where to seek care for complications, are needed in Somaliland. Involvement of religious leaders in anti-FGM/C programs is essential.

Midwives' Experiences in Providing Care and Counselling to Women with Female Genital Mutilation (FGM) Related Problems.

Aim. The aim of this study was to elucidate midwives experiences in providing care and counselling to women with FGM related problems. Setting. The study was conducted at a maternity clinic in Hargeisa, Somaliland. Method. A qualitative, inductive study were performed with eight midwives living in Somaliland. The interviews had semi-structured questions. Content analysis was used for the analysis. Findings. The main findings of the present study were how midwives are challenged by culture and religion when providing FGM counselling. The most prominent challenge is the perception that FGM is an important part of the culture and from this point of view the midwives work is apprehended as interfering and subverting the Somali culture. Having personal experience of FGM emerged as a benefit when counselling women. Conclusion. There is a contradiction between the professional actions of performing FGM despite a personal belief against FGM. Midwives as a professional group could be important agents of change and further research is needed about the midwives role in this process.

Yemeni women's perceptions of own authority during childbirth: what does it have to do with achieving the Millennium Development Goals?

BACKGROUND: women's underutilisation of professional care during childbirth in many low-income countries is a serious concern in terms of achievement of maternal Millennium Development Goal 5. OBJECTIVE: to explore women's perceived own authority within the modern and traditional spheres of childbirth in a high maternal mortality setting on the Arab peninsula. Yemen is a signatory to the Millennium Development Goals and one of 10 countries chosen for the United Nations Millennium Project. In Yemen, home birth has remained the norm for several decades in spite of high maternal mortality and morbidity rates. DESIGN: a multistage (stratified-purposive-random) sampling process was used. Two hundred and twenty women with childbirth experience in urban/rural Yemen were selected at random for interview. Answers to the question 'Did you feel that you were the authority during childbirth?' were analysed using qualitative content analysis. SETTING: the governorates of Aden, Lahej, Hadramout, Taiz and Hodeidah. FINDINGS: three main themes emerged from the analysis: (i) 'Being at the centre', including two categories 'being able to follow through on own wants' and its opposite 'to be under the authority of others'; (ii) 'A sense of belonging' with the categories 'belonging and support among women in the community' and 'the denial of support, the experience of separation' and (iii) 'Husband's role in childbirth' including one category 'opportunity to show authority over the husband'. Authority was experienced primarily among women within the traditional childbirth sector although a general complaint among women delivered by trained medical staff was the loss of own authority. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: these findings show that women's authority during childbirth is decreasing in the context of Safe Motherhood and the expansion of modern delivery care. This is likely to be an important reason why women underutilise professional care. Acquisition of knowledge from the traditional childbirth sector regarding how women exercise authority to facilitate childbirth would constitute an asset to skilled delivery and Safe Motherhood. The findings from Yemen are likely to be relevant for other low-income countries with similar persistent high home delivery rates, low status of women, and high maternal mortality and morbidity rates.

Sex of newborns associated with place and mode of delivery: a population-based study in northern Vietnam.

BACKGROUND: There is increasing evidence of an elevated sex ratio at birth (SRB) in many Asian countries, including Vietnam, and that this prenatal gender inequity is related to sex-selective abortion. However, few studies have investigated the relation between the sex of offspring and delivery care utilization. OBJECTIVE: The aim of the present study was to relate sex of newborns to place and mode of delivery in a province in northern Vietnam. METHODS: A population-based surveillance system within the Neonatal Health-Knowledge Into Practice (NeoKIP) project (ISRCTN44599712) recorded all births within eight districts of Quang Ninh province in northern Vietnam from July 2008 to June 2011. RESULTS: In total, there were 22,377 live births within the study area. SRB was 108 boys per 100 girls. There was a large difference in SRB depending on place of delivery, with 94 boys per 100 girls being delivered at home, whereas 113 boys per 100 girls were delivered at a district-level hospital. Cesarean section (CS) rate was 17%, and within the CS group, the SRB was 135:100. CONCLUSIONS: We demonstrated an elevated SRB, especially at district hospital level, and that sex of offspring influenced place and mode of delivery. Although mothers to boys were more likely to receive more qualified delivery care, they were at the same time more likely to undergo unnecessary surgery. Correct information to women and family members about CS and stricter implementation of the medical indications for CS are urgently called for.

Endotoxin-induced and vaccine-induced systemic inflammation both impair endothelium-dependent vasodilation, but not pulse wave reflection.

BACKGROUND: Inflammation induced by either endotoxin or vaccination has previously been shown to impair endothelium-dependent vasodilation (EDV) in healthy young individuals. However, the vascular effects of these two mechanisms of inducing inflammation have not been compared in the same individuals. METHODS: Twelve young healthy males were studied at the same time of the day on three occasions in a random order; on one occasion 4 hours following an endotoxin injection (Escherichia coli endotoxin, 20 IU/kg), on another occasion 8 hours following vaccination against Salmonella typhi, and on a third occasion 4 hours following a saline control injection. EDV and endothelium-independent vasodilation (EIDV) were evaluated by local infusions of acetylcholine and sodium nitroprusside in the brachial artery, and forearm blood flow was measured with venous occlusion plethysmography. The augmentation index was determined by pulse wave analysis as an index of pulse wave reflection. RESULTS: Both endotoxin and vaccination impaired EDV to a similar degree compared with the saline control (P = 0.005 and P = 0.014, respectively). EIDV was not significantly affected by inflammation. Endotoxin, but not vaccination, increased body temperature and circulating levels of intracellular adhesion molecule-1 and interleukin-6. Augmentation index was not affected by the interventions. CONCLUSION: Despite the fact that endotoxin induced a more pronounced degree of inflammation than vaccination, both inflammatory challenges impaired EDV to a similar degree, supporting the view that different inflammatory stimuli could induce harmful effects on the vasculature.

Married men's first time experiences of early childbearing and their role in sexual and reproductive decision making: a qualitative study from rural Vietnam.

Male partners' involvement in women's sexual and reproductive health has been increasingly emphasised in international health. A qualitative approach with open-ended qualitative interviews was used to explore young, married men's first time experiences of early childbearing, their sexual and reproductive decision making and the meanings they make of their role as husbands and fathers. The results offer a nuanced picture of the men's vulnerability in becoming young fathers and having to assume their role as family decision-makers, while still being inexperienced in matters related to the health of their wives and newborn child. Constraints to gender equality and traditional norms and values continue to pose barriers to both young men and women making independent decisions in relation to marriage and childbearing. Men's involvement is necessary in healthcare programmes designed to improve women's sexual and reproductive health and the health of the newborn. Young, first-time fathers, in particular, need support and empowerment.