bluuebunny/crossref_metadata_2025 huggingface dataset:
Thin set theorems and cone avoidance
Authors: Cholak Peter , Patey Ludovic
Published: September 2019

The thin set theorem

R
T

>
∞
,
ℓ

n

\operatorname {\mathsf {RT}}^n_{>\infty ,\ell }

asserts the existence, for every

k
k

-coloring of the subsets of natural numbers of size

n
n

, of an infinite set of natural numbers, all of whose subsets of size

n
n

use at most

ℓ
\ell

colors. Whenever

ℓ
=
1

\ell = 1

, the statement corresponds to Ramsey’s theorem. From a computational viewpoint, the thin set theorem admits a threshold phenomenon, in that whenever the number of colors

ℓ
\ell

is sufficiently large with respect to the size

n
n

of the tuples, the thin set theorem admits strong cone avoidance.

Let

d
0

,

d
1

,
…

d_0, d_1, \dots

be the sequence of Catalan numbers. For

n
≥
1

n \geq 1

,

R
T

>
∞
,
ℓ

n

\operatorname {\mathsf {RT}}^n_{>\infty , \ell }

admits strong cone avoidance if and only if

ℓ
≥

d
n

\ell \geq d_n

and cone avoidance if and only if

ℓ
≥

d

n
−
1

\ell \geq d_{n-1}

. We say that a set

A
A

is

R
T

>
∞
,
ℓ

n

\operatorname {\mathsf {RT}}^n_{>\infty , \ell }

-encodable if there is an instance of

R
T

>
∞
,
ℓ

n

\operatorname {\mathsf {RT}}^n_{>\infty , \ell }

such that every solution computes

A
A

. The

R
T

>
∞
,
ℓ

n

\operatorname {\mathsf {RT}}^n_{>\infty , \ell }

-encodable sets are precisely the hyperarithmetic sets if and only if

ℓ
>

2

n
−
1

\ell > 2^{n-1}

, the arithmetic sets if and only if

2

n
−
1

≤
ℓ
>

d
n

2^{n-1} \leq \ell > d_n

, and the computable sets if and only if

d
n

≤
ℓ

d_n \leq \ell

.
Weak membrane interactions allow Rheb to activate mTORC1 signaling without major lysosome enrichment
Authors: Angarola Brittany , Ferguson Shawn M.
Published: September 2019

Stable localization of the Rheb GTPase to lysosomes is thought to be required for activation of mTOR complex 1 (mTORC1) signaling. However, the lysosome targeting mechanisms for Rheb remain unclear. We therefore investigated the relationship between Rheb subcellular localization and mTORC1 activation. Surprisingly, we found that Rheb was undetectable at lysosomes. Nonetheless, functional assays in knockout human cells revealed that farnesylation of the C-terminal CaaX motif on Rheb was essential for Rheb-dependent mTORC1 activation. Although farnesylated Rheb exhibited partial endoplasmic reticulum (ER) localization, constitutively targeting Rheb to ER membranes did not support mTORC1 activation. Further systematic analysis of Rheb lipidation revealed that weak, nonselective, membrane interactions support Rheb-dependent mTORC1 activation without the need for a specific lysosome targeting motif. Collectively, these results argue against stable interactions of Rheb with lysosomes and instead that transient membrane interactions optimally allow Rheb to activate mTORC1 signaling.
Kinetochore-mediated outward force promotes spindle pole separation in fission yeast
Authors: Shirasugi Yutaka , Sato Masamitsu
Published: September 2019

Bipolar spindles are organized by motor proteins that generate microtubule-­dependent forces to separate the two spindle poles. The fission yeast Cut7 (kinesin-5) is a plus-end-directed motor that generates the outward force to separate the two spindle poles, whereas the minus-end-directed motor Pkl1 (kinesin-14) generates the inward force. Balanced forces by these antagonizing kinesins are essential for bipolar spindle organization in mitosis. Here, we demonstrate that chromosomes generate another outward force that contributes to the bipolar spindle assembly. First, it was noted that the cut7 pkl1 double knockout failed to separate spindle poles in meiosis I, although the mutant is known to succeed it in mitosis. It was assumed that this might be because meiotic kinetochores of bivalent chromosomes joined by cross-overs generate weaker tensions in meiosis I than the strong tensions in mitosis generated by tightly tethered sister kinetochores. In line with this idea, when meiotic mono-oriented kinetochores were artificially converted to a mitotic bioriented layout, the cut7 pkl1 mutant successfully separated spindle poles in meiosis I. Therefore, we propose that spindle pole separation is promoted by outward forces transmitted from kinetochores to spindle poles through microtubules.
Relaxation Therapy for Hypertension: Design Effects and Treatment Effects2
Authors: Jacob Rolf G. , Chesney Margaret A. , Williams David M. , Ding Yijun , Shapiro Alvin P.
Published: September 2019

The outcome literature on relaxation therapy for hypertension is surveyed and compared with the results of a recent meta-analysis, the Hypertension Intervention Pooling Project (HIPP). The results in the literature appear more favorable than those obtained in the HIPP. It seems that different impressions regarding the efficacy of relaxation therapy are reached depending on whether all studies or only methodologically sophisticated studies are examined. Besides pre-treatment pressure, the effect of baseline entry characteristics of a study were found to affect outcome: the largest declines in systolic pressure were reported in studies that included only one baseline session and used patients who were new to the outcome measurement setting. Comparing the changes of blood pressure in response to different treatment modalities yielded few differences once the effects of pre-treatment pressure and baseline entry characteristics had been considered; nevertheless, further research might be indicated to assess the effect of stress- or anxiety-management and EMG-biofeedback-assisted relaxation, using appropriate designs. The possibility of patient characteristics predisposing to successful treatment outcome was considered, but no clear findings are available at this time. A final concern is a possible lack of generalization of the relaxation effect outside of the blood pressure measurement situation; the declines in blood pressure observed with relaxation therapy may be transient and specific for the measurement situation.
Distribution of the National Early Warning Score (NEWS) in care home residents
Authors: Barker Robert Oliver , Stocker Rachel , Russell Siân , Roberts Anthony , Kingston Andrew , Adamson Joy , Hanratty Barbara
Published: September 2019

Background

the National Early Warning Score (NEWS) is a tool based on vital signs that aims to standardise detection of, and response to, clinical deterioration in adults. NEWS has been adopted in hospitals but not adapted for other settings. This study aimed to explore the feasibility of measuring the NEWS in care homes and describe the distribution of NEWS readings amongst care home residents.

Methods

descriptive analysis of all NEWS readings recorded in a 30-month period (2016–19) across 46 care homes in one Clinical Commissioning Group in England. Comparisons were made between measurements taken as a routine reading and those prompted by concern about acute illness.

Results

a total of 19,604 NEWS were recorded from 2,424 older adults (≥65 years; mean age 85). Median NEWS was 2. Two thirds (66%) of residents had a low NEWS (≤2), and 28% had a score of 0. Of the total NEWS readings, 6,277 (32%) were known to be routine readings and 2,256 (12%) were measured because of staff concerns. Median NEWS was 1 for routine and 2 for concern recordings. Overall, only 12% of NEWS were high (≥5), but a higher proportion were elevated when there were concerns about acute illness (18%), compared with routine recordings (7%).

Conclusions

use of NEWS in care homes appears to be feasible. The majority of NEWS were not elevated, and the distribution of scores is consistent with other out-of-hospital settings. Further work is required to know if NEWS is triggering the most appropriate response and improving care home resident outcomes.
Commentary: Economics and American Literary Studies in the New Gilded Age
Authors: Eby Clare
Published: September 2019

The marginalization of the humanities, while depressing, has at least provoked literary scholars into rethinking what they do and foregrounding the relevance of their research. The spike of interest in the economic humanities illustrates one path for making literary study more legible. To that end, several trends emerge in recent economic-themed literary scholarship. One trend of establishing the salience of humanistic scholarship proceeds by locating the origins of present concerns, such as the corporate takeover of democracy, in the past. While that approach is exciting and engaging, care must be taken not to flatten out differences between historical periods. A second salutary trend of making the humanities more intelligible develops interventionist and activist modes of scholarship—for instance, in the interest of making the economy more equitable, and by suggesting alternatives to current impasses. Through such approaches, the economic humanities can help demystify the epistemology of capitalism, the mental barrier determining what is and is not thinkable.
CSF sTREM2 and Tau Work Together in Predicting Increased Temporal Lobe Atrophy in Older Adults
Authors: Halaas Nathalie Bodd , Henjum Kristi , Blennow Kaj , Dakhil Shams , Idland Ane-Victoria , Nilsson Lars NG , Sederevicius Donatas , Vidal-Piñeiro Didac , Walhovd Kristine B , Wyller Torgeir Brunn , Zetterberg Henrik , Watne Leiv Otto , Fjell Anders M
Published: September 2019

Neuroinflammation may be a key factor in brain atrophy in aging and age-related neurodegenerative disease. The objective of this study was to test the association between microglial expression of soluble Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2), as a measure of neuroinflammation, and brain atrophy in cognitively unimpaired older adults. Brain magnetic resonance imagings (MRIs) and cerebrospinal fluid (CSF) sTREM2, total tau (t-tau), phosphorylated181 tau (p-tau), and Aβ42 were analyzed in 115 cognitively unimpaired older adults, classified according to the A/T/(N)-framework. MRIs were repeated after 2 (n = 95) and 4 (n = 62) years. High baseline sTREM2 was associated with accelerated cortical thinning in the temporal cortex of the left hemisphere, as well as bilateral hippocampal atrophy, independently of age, Aβ42, and tau. sTREM2-related atrophy only marginally increased with biomarker positivity across the AD continuum (A−T− #x2292; A+T− #x2292; A+T+) but was significantly stronger in participants with a high level of p-tau (T+). sTREM2-related cortical thinning correlated significantly with areas of high microglial-specific gene expression in the Allen Human Brain Atlas. In conclusion, increased CSF sTREM2 was associated with accelerated cortical and hippocampal atrophy in cognitively unimpaired older participants, particularly in individuals with tau pathology. This suggests a link between neuroinflammation, neurodegeneration, and amyloid-independent tauopathy.
Antimicrobial Resistance Following Azithromycin Mass Drug Administration: Potential Surveillance Strategies to Assess Public Health Impact
Authors: Mack Ines , Sharland Mike , Berkley James A , Klein Nigel , Malhotra-Kumar Surbhi , Bielicki Julia
Published: September 2019

The reduction in childhood mortality noted in trials investigating azithromycin mass drug administration (MDA) for trachoma control has been confirmed by a recent large randomized controlled trial. Population-level implementation of azithromycin MDA may lead to selection of multiresistant pathogens. Evidence suggests that repeated azithromycin MDA may result in a sustained increase in macrolide and other antibiotic resistance in gut and respiratory bacteria. Current evidence comes from standard microbiological techniques in studies focused on a time-limited intervention, while MDA implemented for mortality benefits would likely repeatedly expose the population over a prolonged period and may require a different surveillance approach. Targeted short-term and long-term surveillance of resistance emergence to key antibiotics, especially those from the World Health Organization Access group, is needed throughout any implementation of azithromycin MDA, focusing on a genotypic approach to overcome the limitations of resistance surveillance in indicator bacteria.
Navigating Institutions: Parents’ Knowledge of the Educational System and Students’ Success in Education
Authors: Forster Andrea G , van de Werfhorst Herman G
Published: September 2019

This study investigates whether families navigate educational institutions more successfully if they have a higher knowledge of the pathways in the educational system that are available to their children. We also study whether this kind of knowledge mediates secondary effects of social origin, i.e. differences in educational pathways once achievement differences between children are accounted for. The role of parents’ knowledge is consistent with various sociological theories concerning educational inequality. Knowledge can affect families’ ability to make rational choices for education but it can also be understood as a form of cultural capital. We use longitudinal student cohort data from the Netherlands combined with individual-level register data on educational attainment to study the importance of knowledge for short-term outcomes (up- and downward transitions in secondary education as well as track placement) and final educational attainment. Our results show that parents’ knowledge is a significant predictor of educational success net of parents’ education, socio-demographic characteristics, and demonstrated ability. If we apply a stricter test to the measure, however, we can see that knowledge matters for downward transitions and obtaining a tertiary degree but that the effect is negligible for upward transitions and track placement if other mechanisms such as cultural capital and aspirations are considered. Further, we conclude that knowledge matters especially for transitions in the educational system that require a move to a new and unknown school environment such as post-secondary or tertiary education. The study shows that knowledge is one useful avenue to investigate when we are confronted with the question why social disparities in educational decision-making arise.
A community approach to engaging Gypsy and Travellers’ in cancer services
Authors: Smith David , Newton Paul , Berlin Jenni , Barrett Shirley
Published: September 2019

While cancer outcomes in the UK have improved, inequalities remain with poorer and some ethnic minority populations experiencing lower survival rates. Research has addressed Gypsies’ and Travellers’ cancer-related beliefs, experiences and practices as part of wider studies but this is the first study in the UK to specifically focus on cancer. Findings suggest that health beliefs and practices are shaped by historical and contemporary social processes and the marginal position of Gypsies and Travellers in the UK society can result in a preference for seeking information and support from within the community. Starting from a health assets perspective, findings indicate that the structure of social relations in Gypsy and Traveller communities could be more widely utilized in health promotion programmes. Developing and extending techniques employed by Gypsy and Traveller Non-governmental Organisations such as community-based interventions and the use of lay health advisers, could be an effective method of health promotion by raising knowledge of cancer, engaging community members in preventative programmes and encouraging earlier access to services.
Single-nucleotide polymorphisms in Orai1 associated with atopic dermatitis inhibit protein turnover, decrease calcium entry and disrupt calcium-dependent gene expression
Authors: Yeh Yi-Chun , Lin Yu-Ping , Kramer Holger , Parekh Anant B
Published: September 2019

Loss-of function mutations in Orai1 Ca2+ channels lead to a form of severe combined immunodeficiency, auto-immunity, muscle hypotonia and defects in dental enamel production and sweat gland function. Two single-nucleotide polymorphisms (SNPs) in Orai1 have been found and localize to the second extracellular loop. These polymorphisms associate with atopic dermatitis but how they affect Ca2+ signalling and cell function is unknown. Here, we find that Orai1–SNPs turnover considerably more slowly than wild type Orai1 and are more abundantly expressed in the plasma membrane. We show a central role for flotillin in the endocytotic recycling of Orai1 channels and that endocytosed wild type Orai1 is trafficked to Rab 7-positive late endosomes for lysosomal degradation. Orai1–SNPs escape the degradation pathway and instead enter Rab 11-positive recycling endosomes, where they are returned to the surface membrane through Arf6-dependent exocytosis. We find that Orai1–SNPs escape late endosomes through endosomal pH regulation of interaction between the channel and flotillin. We identify a pH-sensitive electrostatic interaction between positively charged arginine in extracellular loop 2 (K210) and a negatively charged aspartate (D112) in extracellular loop 1 that helps determine Orai1 turnover. The increase in membrane Orai1–SNP leads to a mis-match in Orai1–STIM stoichiometry, resulting in inhibition of Ca2+ entry and Ca2+-dependent gene expression. Our results identify new strategies for targeting atopic dermatitis.
Concentration inequalities for the empirical distribution of discrete distributions: beyond the method of types
Authors: Mardia Jay , Jiao Jiantao , Tánczos Ervin , Nowak Robert D , Weissman Tsachy
Published: September 2019

We study concentration inequalities for the Kullback–Leibler (KL) divergence between the empirical distribution and the true distribution. Applying a recursion technique, we improve over the method of types bound uniformly in all regimes of sample size $n$ and alphabet size $k$, and the improvement becomes more significant when $k$ is large. We discuss the applications of our results in obtaining tighter concentration inequalities for $L_1$ deviations of the empirical distribution from the true distribution, and the difference between concentration around the expectation or zero. We also obtain asymptotically tight bounds on the variance of the KL divergence between the empirical and true distribution, and demonstrate their quantitatively different behaviours between small and large sample sizes compared to the alphabet size.
Using natural language processing to construct a metastatic breast cancer cohort from linked cancer registry and electronic medical records data
Authors: Ling Albee Y , Kurian Allison W , Caswell-Jin Jennifer L , Sledge George W , Shah Nigam H , Tamang Suzanne R
Published: September 2019

Objectives

Most population-based cancer databases lack information on metastatic recurrence. Electronic medical records (EMR) and cancer registries contain complementary information on cancer diagnosis, treatment and outcome, yet are rarely used synergistically. To construct a cohort of metastatic breast cancer (MBC) patients, we applied natural language processing techniques within a semisupervised machine learning framework to linked EMR-California Cancer Registry (CCR) data.

Materials and Methods

We studied all female patients treated at Stanford Health Care with an incident breast cancer diagnosis from 2000 to 2014. Our database consisted of structured fields and unstructured free-text clinical notes from EMR, linked to CCR, a component of the Surveillance, Epidemiology and End Results Program (SEER). We identified de novo MBC patients from CCR and extracted information on distant recurrences from patient notes in EMR. Furthermore, we trained a regularized logistic regression model for recurrent MBC classification and evaluated its performance on a gold standard set of 146 patients.

Results

There were 11 459 breast cancer patients in total and the median follow-up time was 96.3 months. We identified 1886 MBC patients, 512 (27.1%) of whom were de novo MBC patients and 1374 (72.9%) were recurrent MBC patients. Our final MBC classifier achieved an area under the receiver operating characteristic curve (AUC) of 0.917, with sensitivity 0.861, specificity 0.878, and accuracy 0.870.

Discussion and Conclusion

To enable population-based research on MBC, we developed a framework for retrospective case detection combining EMR and CCR data. Our classifier achieved good AUC, sensitivity, and specificity without expert-labeled examples.
Farmers’ Knowledge and Practices in the Management of Insect Pests of Leafy Amaranth in Kenya
Authors: Nampeera Esther L , Nonnecke Gail R , Blodgett Sue L , Tusiime Sharon M , Masinde Dorothy M , Wesonga John M , Murungi Lucy K , Baidu-Forson Joseph J , Abukutsa-Onyango Mary O
Published: September 2019

Amaranth (Amaranthus L.) species are grown for their grain or leaves and contribute to farmers’ livelihoods and nutritional food security. Leafy amaranth (LA) is consumed widely as a vegetable in Kenya. An assessment of current farmers’ knowledge of pest management practices provides information about future educational needs. Six-hundred LA farmers were interviewed, focus group discussions with farmers, and interviews with key informants were completed in four Kenyan counties. The majority (71%) of survey respondents grew LA on less than 0.25 acre (<0.1 ha) and 59.2% were female. Constraints of LA production differed by counties surveyed. Farmers indicated insects and birds were important in Kiambu and Kisumu counties, whereas in Vihiga and Kisii, capital, markets, and land area for production were important. Farmers stated and ranked importance of the insects they observed during LA production. Eighty-seven percent stated aphids (Hemiptera: Aphididae), as a major pest and 96.8% ranked aphids as the number-one insect pest of LA in all four counties. Two other pests of LA included cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae) (0.8%) and spider mites, Tetranychus spp (Trombidiformes; Tetranychidae) (0.7%). Forty-two percent of all LA farmers managed aphids, with 34% using synthetic insecticides and 8% using nonsynthetic methods. Biological controls and host-plant resistance were not mentioned. Educational programs that train farmers about integrated pest management (IPM) in LA production are needed. Future research should determine successful IPM strategies for aphids on LA to reduce insecticide use and improve sustainability and nutritional food security for small-landholder farmers and consumers.
Is Guyana a new oil El Dorado?
Authors: Panelli Luis Fernando
Published: September 2019

The Co-operative Republic of Guyana has become one of the most interesting and dynamic oil producing countries in the world at the start of the 21st century. The country already holds 5 billion barrels of proved reserves, which will certainly grow with new discoveries. Exxon leads a consortium of four companies that have the concession of the Stabroek Block (Liza Field), where nine discoveries have been made so far. Five FPSOs will be operating in the future, one of which is due to arrive in Guyana before the end of 2019 and another is due for 2020. By then, the country will be producing 340,000 barrels a day. This production will double and then reach 1 million barrels a day before the end of the next decade. The challenges and opportunities regarding the Guyanese people are dire. The lack of proper infrastructure is certainly one of the biggest challenges. But it is important to stress that the oil proceeds will transform Guyana into the highest GDP per capita of South America. The political stage is also analysed, since political instability might raise concerns for long-term investors. The Venezuela–Guyana differences regarding the sovereignty of the Essequibo Region are again a cause for concern. Brazil is a key player in supporting the geopolitical stability of South America. Presidential elections will be held in 2019/2020: the dispute will probably be between the current President Granger and the Opposition candidate Irfaan Ali. Guyana has a lot to profit from the wealth brought by oil exploitation, but its people fear the risk of growing corruption.
Stem cell fate in hypoxic root apical meristems is influenced by phytoglobin expression
Authors: Mira Mohammed M , El-Khateeb Eman A , Gaafar Reda M , Igamberdiev Abir U , Hill Robert D , Stasolla Claudio
Published: September 2019

Overexpression of phytoglobin retains stem cell fate specification and function in hypoxic root apical meristems
Clinical Use of κ Free Light Chains Index as a Screening Test for Multiple Sclerosis
Authors: Agnello Luisa , Lo Sasso Bruna , Salemi Giuseppe , Altavilla Patrizia , Pappalardo Emanuela Maria , Caldarella Rosalia , Meli Francesco , Scazzone Concetta , Bivona Giulia , Ciaccio Marcello
Published: September 2019

Objective

To assess the usefulness of the κ free light chain index (κFLCi) as a screening test to identify patients with suspected MS.

Methods

The study included 56 patients with a request to test for oligoclonal bands (OCBs). OCBs were detected by isoelectric focusing, followed by immunofixation. Cerebrospinal fluid (CSF) and serum κFLC were measured by a turbidimetric assay. Also, the κFLC index (κFLCi) was calculated.

Results

CSF κFLC levels and κFLCi were significantly higher in patients with multiple sclerosis (MS) than in patients with other neurological diseases (NDs; P < .001 and P < .001, respectively). At the cutoff value of 2.9, the κFLCi detected MS with sensitivity of 97% and specificity of 65%. Overall, 92% patients with κFLCi of 2.9 or greater and who had tested positive for OCBs were diagnosed as having MS.

Conclusion

Our findings support the use of κFLCi as a screening test when MS is suspected, followed by OCB detection as a confirmatory test for the diagnosis of MS.
The (Un)Making of a History Book: Revisiting the Earliest Manuscripts of Eadmer of Canterbury’s Historia novorum in Anglia*
Authors: Pohl Benjamin
Published: September 2019

This article revisits the earliest manuscripts of the ‘History of Recent Events in England’ (Historia novorum in Anglia) written by Eadmer of Canterbury during the first decades of the twelfth century. Today, it is widely recognised as one of the most important pieces of historical writing produced in England during the period following the Norman Conquest. The article is the first in over twenty years to offer an in-depth codicological study of the Historia novorum’s principal manuscripts, and it provides a critical corrective to the canonical studies of Richard Southern (1963/90), whose arguments still form the communis opinio in present-day scholarship. Analysis shows that, contrary to established scholarly consensus, Eadmer did not compose his work in two distinct versions separated by a five-year writing hiatus, but that he kept writing continuously and produced one or more interim redactions of the Historia novorum that continued the narrative up to key moments in the history of early twelfth-century England.
The young stellar population of the metal-poor galaxy NGC 6822
Authors: Jones Olivia C , Sharp Michael J , Reiter Megan , Hirschauer Alec S , Meixner M , Srinivasan Sundar
Published: September 2019

We present a comprehensive study of massive young stellar objects (YSOs) in the metal-poor galaxy NGC 6822 using IRAC and MIPS data obtained from the Spitzer Space Telescope. We find over 500 new YSO candidates in seven massive star formation regions; these sources were selected using six colour–magnitude cuts. Via spectral energy distribution fitting to the data with YSO radiative transfer models we refine this list, identifying 105 high-confidence and 88 medium-confidence YSO candidates. For these sources, we constrain their evolutionary state and estimate their physical properties. The majority of our YSO candidates are massive protostars with an accreting envelope in the initial stages of formation. We fit the mass distribution of the Stage I YSOs with a Kroupa initial mass function and determine a global star formation rate of 0.039 $\mathrm{M}_{\odot } \, \mathrm{yr}^{-1}$. This is higher than star formation rate estimates based on integrated UV fluxes. The new YSO candidates are preferentially located in clusters which correspond to seven active high-mass star-formation regions which are strongly correlated with the 8 and 24 μm emission from PAHs and warm dust. This analysis reveals an embedded high-mass star formation region, Spitzer I, which hosts the highest number of massive YSO candidates in NGC 6822. The properties of Spitzer I suggest it is younger and more active than the other prominent H ii and star-formation regions in the galaxy.
The excitation of NH2 in the interstellar medium
Authors: Bouhafs N , Bacmann A , Faure A , Lique F
Published: September 2019

Accurate estimation of the abundance of the NH2 radical in the interstellar medium requires accurate radiative and collisional rate coefficients. The calculation of hyperfine-resolved rate coefficients for the collisional (de-)excitation of NH2 by both ortho- and para-H2 is presented in this work. Hyperfine-resolved rate coefficients are calculated from pure rotational close-coupling rate coefficients using the Mj randomizing approximation. Rate coefficients for temperatures ranging from 5 to 150 K were computed for all hyperfine transitions among the first 15 rotational energy levels of both ortho- and para-NH2 in collisions with ortho- and para-H2. The new data were then employed in radiative transfer calculations to simulate the excitation of NH2 in typical star-forming regions such as W31C, where NH2 is seen in emission. We compared the excitation and brightness temperatures for different NH2 transitions obtained using the new and the previously available collisional data. It is found that the new rate coefficients increase the simulated line intensities by a factor ∼10–30. As a consequence, NH2 abundance derived from the observations will be significantly reduced by the use of the present rate coefficients.
Constraints on the production and escape of ionizing radiation from the emission-line spectra of metal-poor star-forming galaxies
Authors: Plat A , Charlot S , Bruzual G , Feltre A , Vidal-García A , Morisset C , Chevallard J , Todt H
Published: September 2019

We explore the production and escape of ionizing photons in young galaxies by investigating the ultraviolet and optical emission-line properties of models of ionization-bounded and density-bounded H ii regions, active-galactic-nucleus (AGN) narrow-line regions, and radiative shocks computed all using the same physically consistent description of element abundances and depletion on to dust grains down to very low metallicities. We compare these models with a reference sample of metal-poor star-forming galaxies and Lyman-continuum (LyC) leakers at various redshifts, which allows the simultaneous exploration of more spectral diagnostics than typically available at once for individual subsamples. We confirm that current single- and binary-star population synthesis models do not produce hard-enough radiation to account for the high-ionization emission of the most metal-poor galaxies. Introducing either an AGN or radiative-shock component brings models into agreement with observations. A published model including X-ray binaries is an attractive alternative to reproduce the observed rise in He iiλ4686/H β ratio with decreasing oxygen abundance in metal-poor star-forming galaxies, but not the high observed He iiλ4686/Hβ ratios of galaxies with large EW(Hβ). A source of harder ionizing radiation appears to be required in these extreme objects, such as an AGN or radiative-shock component, perhaps linked to an initial-mass-function bias towards massive stars at low metallicity. This would also account for the surprisingly high [O i]/[O iii] ratios of confirmed LyC leakers relative to ionization-bounded models. We find no simple by-eye diagnostic of the nature of ionizing sources and the escape of LyC photon, which require proper simultaneous fits of several lines to be discriminated against.
The peculiar chemistry of the inner ejecta of Eta Carina
Authors: Bordiu Cristobal , Rizzo J Ricardo
Published: September 2019

We investigated continuum and molecular line emission of four species (CO, HCN, H13CN, and HCO+) at 0.8 mm in the inner region around η Car, using ALMA archival observations at a resolution better than 0.2 arcsec. We report the discovery of an asymmetric extended structure north-west of the star, independent from the continuum point source. The structure is only traced by continuum and HCO+, and not detected in the other lines. Kinematics of this structure reveal that the HCO+ gas likely arises from ejecta expelled in the 1890s eruption. The ejecta is propagating outwards within the cavity produced by the current wind–wind interaction of η Car A and its companion. Chemical analysis of the ejecta reveals an apparent lack of CO and nitrogen-bearing species. We explore possible explanations for this peculiar chemistry, that differentiates this structure from the ejecta of the Great Eruption, rich in HCN and H13CN. We also report an absorption component near the continuum point source, only traced by HCN and H13CN in their vibrational-ground and vibrationally excited states. This absorbing gas is attributed to a hot bullet of N-enriched material expelled at a projected velocity of 40 km s−1.
Substrate conformational dynamics facilitate structure-specific recognition of gapped DNA by DNA polymerase
Authors: Craggs Timothy D , Sustarsic Marko , Plochowietz Anne , Mosayebi Majid , Kaju Hendrik , Cuthbert Andrew , Hohlbein Johannes , Domicevica Laura , Biggin Philip C , Doye Jonathan P K , Kapanidis Achillefs N
Published: September 2019

DNA-binding proteins utilise different recognition mechanisms to locate their DNA targets; some proteins recognise specific DNA sequences, while others interact with specific DNA structures. While sequence-specific DNA binding has been studied extensively, structure-specific recognition mechanisms remain unclear. Here, we study structure-specific DNA recognition by examining the structure and dynamics of DNA polymerase I Klenow Fragment (Pol) substrates both alone and in DNA–Pol complexes. Using a docking approach based on a network of 73 distances collected using single-molecule FRET, we determined a novel solution structure of the single-nucleotide-gapped DNA–Pol binary complex. The structure resembled existing crystal structures with regards to the downstream primer-template DNA substrate, and revealed a previously unobserved sharp bend (∼120°) in the DNA substrate; this pronounced bend was present in living cells. MD simulations and single-molecule assays also revealed that 4–5 nt of downstream gap-proximal DNA are unwound in the binary complex. Further, experiments and coarse-grained modelling showed the substrate alone frequently adopts bent conformations with 1–2 nt fraying around the gap, suggesting a mechanism wherein Pol recognises a pre-bent, partially-melted conformation of gapped DNA. We propose a general mechanism for substrate recognition by structure-specific enzymes driven by protein sensing of the conformational dynamics of their DNA substrates.
Determinism and Obligation
Authors: Haji Ishtiyaque
Published: September 2019

Chapter 2 addresses the deterministic horn. Whether determinism threatens obligation turns partly but pivotally on whether the alternatives obligation requires are of the sort that one can have even if determinism is true (weak alternatives) or of the sort determinism precludes one from having (strong alternatives). A line of reasoning for the view that obligation presupposes only that that agents have weak alternatives is evaluated. The chapter concludes with the argument that even if a teleological account of reasons explanation, according to which actions are to be explained in terms of the goals of agents and not in terms of whether they are caused by appropriate mental items (or their neural realizers), is true, determinism still threatens obligation if obligation requires strong alternatives.
The Extended Luck Problem
Authors: Haji Ishtiyaque
Published: September 2019

Chapter 4 continues critical discussion of the cross-world or present luck problem regarding obligation. It assesses various responses to this problem, including responses by teleological theorists about action explanation, agent causalists, and event causalists. It evaluates the view that so-called non-action-centered varieties of libertarianism (as opposed to action-centered varieties) bypass this objection. It discusses why the phenomenon of “tracing” with respect to obligation—the freedom of an action that is obligatory may be inherited from a previously performed free action—is not promising. It argues, finally, that this sort of luck objection is far reaching. It affects non-moral varieties of obligation, such as prudential obligation, and extends to best-from-one’s-own-point-of-view judgments that play a vital role in our practical deliberations.
Enfranchised
Authors: Andreas Joel
Published: September 2019

Chapter 2 recounts how the Chinese Communist Party reorganized industrial enterprises after taking power in 1949. Small numbers of party cadres, typically peasant veterans of the rural insurgency, were dispatched to factories to mobilize workers to attack capitalists and incumbent managers. Through a series of aggressive mass campaigns, the party established its control, recruiting workers to serve as factory leaders and creating party-led institutions of participation. After nationalization was completed in 1956, Mao—concerned that Communist cadres were becoming autocratic and arrogant—initiated a Party Rectification campaign, in which he encouraged unusually freewheeling criticism of “bureaucratism” among party officials. This opening unleashed a torrent of criticism by intellectuals as well as strikes by workers and inspired union leaders to push for greater independence from the party. The campaign, however, was quickly aborted and during the subsequent Anti-Rightist movement those who had spoken out were harshly punished, squelching prospects for autonomous activity.
Participatory Paternalism
Authors: Andreas Joel
Published: September 2019

Chapter 3 describes the institutional foundations of the Chinese work unit system and the practices of worker participation in the early 1960s, after the system was fully established and before the onset of the Cultural Revolution. Participatory institutions included self-managing teams on the shop floor, technical innovation groups, factory elections, representative congresses, and other mechanisms designed to solicit suggestions from below, learn about and defuse employees’ grievances and concerns, and mobilize workers to monitor and criticize factory leaders. Despite high levels of participation, predicated on lifetime job tenure and relatively egalitarian distribution, industrial governance was democratic only in a very limited sense. The party insisted on maintaining a political monopoly and harshly suppressed any hint of independent political activity. Not only was the scope of workers’ influence restricted largely to the shop floor, but they also had little autonomy. Although participation was extensive, the system was more paternalistic than democratic.
Big Democracy
Authors: Andreas Joel
Published: September 2019

Chapter 5 recounts the initial upheavals of the Cultural Revolution, when Mao called on workers to form “rebel” organizations to challenge the authority of the party leadership in their factories. Mao called this unbridled political participation “Big Democracy,” which he contrasted to more civil and institutionalized forms. By fomenting a movement independent of the party organization and loyal to no one but himself, Mao was able to introduce greater autonomy into mass supervision, with lasting consequences for cadre behavior. Local party cadres were criticized for abusing their power, seeking privileges, suppressing criticism from below, isolating themselves from the masses, and governing in a bureaucratic fashion. Virtually all were thrown out of office, and rebel groups were invited to help decide who among them were fit to be rehabilitated. After the party organization was paralyzed, however, factories polarized into rebel and conservative camps and the country descended into increasingly violent factional contention.
Revolutionary Committees
Authors: Andreas Joel
Published: September 2019

Chapter 6 recounts what happened after Mao, unwilling to allow the establishment of permanent autonomous organizations, called for factories to be governed by new “revolutionary committees,” that included veteran cadres and rebel leaders, as well as military officers assigned to oversee this volatile combination. Rebel leaders were supposed to serve as “mass representatives,” but after their organizations were disbanded, they lost the political base that had given them autonomous power and were no longer accountable to their constituencies. With the masses sidelined, the subsequent factional contention between “new” and “old” cadres hardly served as effective mass supervision. Moreover, this institutionalized form of contention was entirely dependent on Mao’s personal authority and was dismantled with the purge of the radical faction that followed his death in 1976. For all their destructive power, the political experiments of this period failed to do much to make leaders more accountable to those below them.
Reforming the Work Unit System
Authors: Andreas Joel
Published: September 2019

Chapter 7 looks at the impact on factory governance of the initial reforms carried out during the first decade and a half after Mao’s death in 1976. These reforms left the fundamental features of the work unit system—public ownership and permanent job tenure—in place, and institutional forms of participation, including staff and workers congresses, were revived and enhanced. During the “long 1980s” workers enjoyed substantial influence, especially with regard to the distribution of wages and bonuses, housing, and other welfare entitlements. Although the Chinese Communist Party had by then renounced its original class-leveling mission, workers effectively resisted new distribution policies that violated the egalitarian ethos that had long prevailed under the work unit system. The latter years of this period, however, also marked the beginning of the erosion of industrial citizenship as temporary employment was expanded and the power of the factory director was reinforced in the second half of the decade.
Lessons and Prospects
Authors: Andreas Joel
Published: September 2019

Chapter 9 looks back over China’s history since 1949 and considers prospects for the future. Chinese workers are beginning to reorganize, this time largely outside the confines of party-controlled institutions, and their strikes and protests have won important victories. Until they are able to regain some form of workplace citizenship rights, however, their gains will be limited and precarious. The chapter closes with an overview of parallel developments around the globe. It first examines three waves of labor unrest during the twentieth century that gave rise to the participatory institutions that characterized the era of industrial citizenship, before describing the subsequent demise of these institutions.
Communities in the Playing Field of Pluralism
Authors: Oruc Firat
Published: September 2019

This chapter aims to examine critically the concept of pluralism in the Middle East as a multidimensional site of negotiation and contestation. It approaches the question of pluralism and community in the Middle East as the lived experience of populations constantly negotiating the state-sanctioned inclusion and exclusion mechanisms. Rather than addressing the question of pluralism and community through the framework of "minorities," this chapter aims to offer a wider perspective on the impact of state policies on the diversity and heterogeneity of national identities as manifested at multiple levels, including education, law, cultural heritage, urbanism, economic activities and citizenship.
Formal Education Systems as Arenas of Inclusion and Exclusion
Authors: Rabo Annika
Published: September 2019

This chapter focuses on formal education in Lebanon and Syria to discuss inclusion and exclusion in plural societies. Both countries are linguistically, religiously, and ethnically heterogeneous but manage this diversity in very different ways in the educational systems. Empirical material used stretches from the 1980s until today. Curriculum theory provides a theoretical frame of reference for an analysis of school subjects such as civics, religious education and history. What is included and what is excluded is an indicator of values propagated by the educational authorities.
Emigrants, Immigrants, and Refugees
Authors: Carter Niambi Michele
Published: September 2019

This chapter presents a historical view of black opinion on immigration. In particular, it looks at the colonization movement of the nineteenth century and the ways in which blacks employed the concept of immigration as a way to escape racial oppression. In fact, blacks applied the term immigrant to their community and seriously considered leaving the United States, with some relocating to Canada and Liberia, for example. The goal of this chapter is to demonstrate blacks’ long-term engagement with the issue of immigration as part of their political tradition. Using primary documents, the chapter helps to demonstrate the depth and range of ways in which blacks have viewed immigration over time.
Conflicted Nativism
Authors: Carter Niambi Michele
Published: September 2019

This chapter tests a number of the propositions of the book empirically, using an original survey. The data demonstrate blacks have some superficially nativist attitudes, particularly those blacks who see themselves as prototypical Americans. These nativist attitudes are attenuated, however, by increasing levels of national pride. Moreover, blacks express a feeling of closeness with immigrants, particularly continental Africans, than native-born whites. At the same time, blacks support the idea of more border security but, in the main, have not even participated in the most minimal of political acts either in support of or against any immigration policy. This suggests immigration is not a salient issue for blacks, and to the extent they care about immigration, they are not willing to put any of their political energies toward the issue.
From Europhilia to Europhobia?
Authors: Graney Katherine
Published: September 2019

This chapter introduces the author’s argument about Europeanization in the period since 1989, including the idea of a “Eurocentric-Orientalist Cultural Gradient” that guides understandings about Europe on both sides of the former Iron Curtain. It identifies three main phases of Europeanization since 1989: Europhoria, Europhilia, and Europhobia; three sets of actors working together to produce new institutional and ideational understandings of Europe since 1989: European gatekeepers in European institutions, the other great power in the region (Russia), and the ex-Soviet republics themselves; and three forces that animate the processes of Europeanization: the Eurocentric-Orientalist Cultural Gradient, values-based commitments of European institutions like the EU and NATO, and the instrumental concerns of Russia and the post-Soviet states. The chapter also briefly explores the three realms within which these processes of Europeanization play themselves out—the cultural-civilizational, the political, and the security realm.
Political Europeanization since 1989
Authors: Graney Katherine
Published: September 2019

This chapter examines the process of EU expansion into the former Soviet Union since 1989, identifying the different criteria that have been used to judge candidates for EU membership. The Central European and Baltic states successfully made arguments about their “intrinsic Europeanness” and “belonging” to Europe and the EU, while the Balkan states have had a harder time proving their suitability for Europe. Unlike the Baltic states, the other ex-Soviet republics, like Ukraine and Georgia, have had a harder time convincing the EU of their fitness for membership, that is, their “intrinsic Europeanness,” and have had to settle for being made “Eastern Partners” of the EU and signers of Association Agreements with the EU. Russia has sought a form of partnership with the EU, while rejecting any idea of conditionality. Finally, the EU shows little concern for the ex-Soviet states of Central Asia, not seeing them as fundamentally European in any way.