bluuebunny/crossref_metadata_2025 huggingface dataset:
Lorentzian Metrics Null-Projectively Related to Semi-Riemannian Metrics
Authors: Olea Benjamín , Palomo Francisco J.
Published: December 2022

We say that a Lorentzian metric and a semi-Riemannian metric on the same manifold M are null-projectively related if every null geodesic of the Lorentzian metric is an unparametrized geodesic of the semi-Riemannian one. This definition includes the case of conformally related Lorentzian metrics and the case of projectively equivalent metrics. We characterize the null-projectively relation by means of certain tensor and provide some examples. Then, we focus on the special case in which both metrics share parametrized null geodesics. In this case, it is said that they are null related. We show how to construct projectively equivalent metrics via a conformal transformation from null-related ones and conversely. The classical Levi-Civita theorem on projectively equivalent metrics is adapted to the case of null-related metrics and some results ensuring that two null-related metric are affinely equivalent are proven under curvature conditions.
Application of Non-singular Kernel in a Tumor Model with Strong Allee Effect
Authors: Khajanchi Subhas , Sardar Mrinmoy , Nieto Juan J.
Published: December 2022

We obtain the analytical solutions in implicit form of a tumor cell population differential equation with strong Allee effect. We consider the ordinary case and then a fractional version. Some particular cases are plotted.
A Systematic Review on Participant Diversity in Clinical Trials—Have We Made Progress for the Management of Obesity and Its Metabolic Sequelae in Diet, Drug, and Surgical Trials
Authors: Johnson-Mann Crystal N. , Cupka Julie S. , Ro Alexandra , Davidson Andrea E. , Armfield Brooke A. , Miralles Frank , Markal Asena , Fierman Kiara E. , Hough Victoria , Newsom Mackenzie , Verma Isha , Dozic Abdul-Vehab , Bihorac Azra
Published: December 2022

Objective

Individuals from Black and Hispanic backgrounds represent a minority of the overall US population, yet are the populations most affected by the disease of obesity and its comorbid conditions. Black and Hispanic individuals remain underrepresented among participants in obesity clinical trials, despite the mandate by the National Institutes of Health (NIH) Revitalization Act of 1993. This systematic review evaluates the racial, ethnic, and gender diversity of clinical trials focused on obesity at a national level.

Methods

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review of clinicaltrials.gov, PubMed, Cochrane Central, and Web of Science was undertaken to locate phase 3 and phase 4 clinical trials on the topic of obesity that met associated inclusion/exclusion criteria. Ultimately, 18 studies were included for review.

Results

White non-Hispanic individuals represented the majority of clinical trial participants, as did females. No study classified participants by gender identity. Reporting of race/ethnicity was not uniform, with noted variability among racial/ethnic subgroups.

Conclusions

Our findings suggest that disparities remain in the diverse racial, ethnic, and gender representation of participants engaged in clinical trials on obesity relative to the prevalence of obesity in underrepresented populations. Commitment to inclusive and intentional recruiting practices is needed to increase the representation of underrepresented groups, thus increasing the generalizability of future research.
Study on non-iterative algorithms for center-of-sets type-reduction of Takagi–Sugeno–Kang type general type-2 fuzzy logic systems
Authors: Chen Yang
Published: December 2022

The paper performs the center-of-sets (COS) type-reduction (TR) and de-fuzzification for Takagi–Sugeno–Kang (TSK) type general type-2 fuzzy logic systems (GT2 FLSs) on the basis of the $$\alpha$$
α
-planes expression of general type-2 fuzzy sets. Actually, comparing the popular Karnik–Mendel (KM) algorithms with other non-iterative algorithms is an important question in T2 society. Here the modules of fuzzy inference, COS TR, and de-fuzzification for TSK type GT2 FLSs are discussed by means of non-iterative Nagar–Bardini (NB) algorithms, Nie–Tan (NT) algorithms, and Begian–Melek–Mendel (BMM) algorithms. Simulation instances are constructed to illustrate the performances of three types of non-iterative algorithms compared with the KM algorithms. It is proved that, the proposed non-iterative algorithms can enhance the computational efficiencies significantly, which afford the potential application value for designers of GT2 FLSs.
Unified treatment of Artin-type problems
Authors: Järviniemi Olli , Perucca Antonella
Published: December 2022

Since Hooley’s seminal 1967 resolution of Artin’s primitive root conjecture under the Generalized Riemann Hypothesis, numerous variations of the conjecture have been considered. We present a framework generalizing and unifying many previously considered variants, and prove results in this full generality (under GRH).
A framework for reconstructing transmission networks in infectious diseases
Authors: Najem Sara , Monni Stefano , Hatoum Rola , Sweidan Hawraa , Faour Ghaleb , Abdallah Chadi , Ghosn Nada , Hassan Hamad , Touma Jihad
Published: December 2022

In this paper, we propose a general framework for the reconstruction of the underlying cross-regional transmission network contributing to the spread of an infectious disease. We employ an autoregressive model that allows to decompose the mean number of infections into three components that describe: intra-locality infections, inter-locality infections, and infections from other sources such as travelers arriving to a country from abroad. This model is commonly used in the identification of spatiotemporal patterns in seasonal infectious diseases and thus in forecasting infection counts. However, our contribution lies in identifying the inter-locality term as a time-evolving network, and rather than using the model for forecasting, we focus on the network properties without any assumption on seasonality or recurrence of the disease. The topology of the network is then studied to get insight into the disease dynamics. Building on this, and particularly on the centrality of the nodes of the identified network, a strategy for intervention and disease control is devised.
System asymptotic stability analysis of a kind of complex production processes based on multi-dimensional moving pattern
Authors: Wu Jinxia , Li Jianwei
Published: December 2022

This paper presents a new method to study the system stability of a kind of complex production processes. The system dynamics is described by multi-dimensional pattern class variables instead of state variables or output variables. The system asymptotic stability is defined by system matrix and output class partition. Firstly, “pattern moving space” is constructed by a new maximum entropy clustering method. Multi-dimensional pattern class variables measured by pattern class centers are defined in this new space. Then the nonlinear state space model of the relevant control system is derived and established through two-step prediction model. On the basis of the original stability in Euclidean space, the multi-dimensional pattern moving state space is defined and Lyapunov stability is given in this space. Finally, experimental results show the effectiveness of the proposed conditions.
Phonetics in Language Teaching
Authors: Liu Di , Jones Tamara , Reed Marnie
Published: December 2022

This Element explores ways in which language teachers, especially teachers of English, can benefit from knowledge of phonetics. It also offers recommendations for introducing and improving pronunciation teaching in the classroom. While hoping that this Element is useful to instructors of all languages, the majority of the examples comes from North American English (NAE) and the English language classroom. At the same time, the Element acknowledges that English language teaching is rather different from the teaching of other languages, since nowadays, most interactions around the world in English do not involve a native speaker, and use of English as a lingua franca (ELF) has become widespread. Teachers of English should be aware that their students may not want to mimic all aspects of native-speaker pronunciation; since some native-speaker patterns of speech, such as the extensive simplification and omission of sounds may not be helpful in enhancing intelligibility.
Essence, Triviality, and Fundamentality
Authors: Coates Ashley
Published: December 2022

I defend a new account of constitutive essence on which an entity’s constitutively essential properties are its most fundamental, nontrivial necessary properties. I argue that this account accommodates the Finean counterexamples to classic modalism about essence, provides an independently plausible account of constitutive essence, and does not run into clear counterexamples. I conclude that this theory provides a promising way forward for attempts to produce an adequate nonprimitivist, modalist account of essence. As both triviality and fundamentality in the account are understood in terms of grounding, the theory also potentially has important implications for the relation between essence and grounding.
Canadian Stroke Best Practice Recommendations: Acute Stroke Management, 7th Edition Practice Guidelines Update, 2022
Authors: Heran Manraj , Lindsay Patrice , Gubitz Gord , Yu Amy , Ganesh Aravind , Lund Rebecca , Arsenault Sacha , Bickford Doug , Derbyshire Donnita , Doucette Shannon , Ghrooda Esseddeeg , Harris Devin , Kanya-Forstner Nick , Kaplovitch Eric , Liederman Zachary , Martiniuk Shauna , McClelland Marie , Milot Genevieve , Minuk Jeffrey , Otto Erica , Perry Jeffrey , Schlamp Rob , Tampieri Donatella , van Adel Brian , Volders David , Whelan Ruth , Yip Samuel , Foley Norine , Smith Eric E. , Dowlatshahi Dar , Mountain Anita , Hill Michael D. , Martin Chelsy , Shamy Michel
Published: December 2022

The 2022 update of the Canadian Stroke Best Practice Recommendations (CSBPR) for Acute Stroke Management, 7th edition, is a comprehensive summary of current evidence-based recommendations, appropriate for use by an interdisciplinary team of healthcare providers and system planners caring for persons with an acute stroke or transient ischemic attack. These recommendations are a timely opportunity to reassess current processes to ensure efficient access to acute stroke diagnostics, treatments, and management strategies, proven to reduce mortality and morbidity. The topics covered include prehospital care, emergency department care, intravenous thrombolysis and endovascular thrombectomy (EVT), prevention and management of inhospital complications, vascular risk factor reduction, early rehabilitation, and end-of-life care. These recommendations pertain primarily to an acute ischemic vascular event. Notable changes in the 7th edition include recommendations pertaining the use of tenecteplase, thrombolysis as a bridging therapy prior to mechanical thrombectomy, dual antiplatelet therapy for stroke prevention,1 the management of symptomatic intracerebral hemorrhage following thrombolysis, acute stroke imaging, care of patients undergoing EVT, medical assistance in dying, and virtual stroke care. An explicit effort was made to address sex and gender differences wherever possible. The theme of the 7th edition of the CSBPR is building connections to optimize individual outcomes, recognizing that many people who present with acute stroke often also have multiple comorbid conditions, are medically more complex, and require a coordinated interdisciplinary approach for optimal recovery. Additional materials to support timely implementation and quality monitoring of these recommendations are available at www.strokebestpractices.ca.
Gendered fertility intentions and child schooling: insights on the quantity–quality trade-off from Ethiopia
Authors: Boonaert Eva , Van Hoyweghen Kaat , Feyisa Ashenafi Duguma , Goos Peter , Maertens Miet
Published: December 2022

Fertility decline in human history is a complex enigma. Different triggers have been proposed, among others the increased demand for human capital resulting in parents making a quantity–quality (QQ) trade-off. This is the first study that examines the existence of a QQ trade-off and the possible gender bias by analyzing fertility intentions rather than fertility outcomes. We rely on the unified growth theory to understand the QQ trade-off conceptually and a discrete choice experiment conducted among 426 respondents in Ethiopia to analyze fertility intentions empirically. We confirm the existence of a QQ trade-off only when the number of children is less than six and find that intentions are gendered in two ways: (i) boys are preferred over girls, and (ii) men are willing to trade-off more education in return for more children. Results imply that a focus on both stimulating intentions for education, especially girls' education, and on family size intentions is important to accelerate the demographic transition.
Writing and Reading New Markets: Insurance in Quebec, 1931–1960
Authors: Nelson Heather
Published: December 2022

The Wawanesa Mutual Insurance Company, successful in western Canada, struggled to replicate its business model in Quebec in the 1930s. The absence of financial responsibility law in Quebec, which made purchasing automobile insurance nearly compulsory for drivers, created a unique opportunity. Wawanesa could insure taxis and fleets in a market where uninsured drivers were the norm. To accommodate this change, it became a direct writer in Quebec. The company also loosened its previously rigid management style to allow branch managers to make regionally appropriate decisions. Insurance companies that fled Quebec in the 1940s would struggle to compete upon their return, because Wawanesa became a market leader. The introduction of financial responsibility law in the province in 1961 would grow the company in the years that followed. As historians work to understand the importance of regional and legislative change to the insurance industry, this story provides a snapshot of a single company in a single market.
The complete separation of the two finer asymptotic structures for <
Authors: Argyros Spiros A. , Georgiou Alexandros , Manoussakis Antonis , Motakis Pavlos
Published: December 2022

For

$1\le p <\infty $

, we present a reflexive Banach space

$\mathfrak {X}^{(p)}_{\text {awi}}$

, with an unconditional basis, that admits

$\ell _p$

as a unique asymptotic model and does not contain any Asymptotic

$\ell _p$

subspaces. Freeman et al., Trans. AMS.370 (2018), 6933–6953 have shown that whenever a Banach space not containing

$\ell _1$

, in particular a reflexive Banach space, admits

$c_0$

as a unique asymptotic model, then it is Asymptotic

$c_0$

. These results provide a complete answer to a problem posed by Halbeisen and Odell [Isr. J. Math.139 (2004), 253–291] and also complete a line of inquiry of the relation between specific asymptotic structures in Banach spaces, initiated in a previous paper by the first and fourth authors. For the definition of

$\mathfrak {X}^{(p)}_{\text {awi}}$

, we use saturation with asymptotically weakly incomparable constraints, a new method for defining a norm that remains small on a well-founded tree of vectors which penetrates any infinite dimensional closed subspace.
Near-surface seismic anisotropy in Antarctic glacial snow and ice revealed by high-frequency ambient noise
Authors: Chaput Julien , Aster Rick , Karplus Marianne , Nakata Nori , Gerstoft P. , Bromirski P. D. , Nyblade A. , Stephen R. A. , Wiens D. A.
Published: December 2022

Ambient seismic recordings taken at broad locations across Ross Ice Shelf and a dense array near West Antarctic Ice Sheet (WAIS) Divide, Antarctica, show pervasive temporally variable resonance peaks associated with trapped seismic waves in near-surface firn layers. These resonance peaks feature splitting on the horizontal components, here interpreted as frequency-dependent anisotropy in the firn and underlying ice due to several overlapping mechanisms driven by ice flow. Frequency peak splitting magnitudes and fast/slow axes were systematically estimated at single stations using a novel algorithm and compared with good agreement with active source anisotropy measurements at WAIS Divide determined via active sources recorded on a 1 km circular array. The approach was further applied to the broad Ross Ice Shelf (RIS) array, where anisotropy axes were directly compared with visible surface features and ice shelf flow lines. The near-surface firn, depicted by anisotropy above 30 Hz, was shown to exhibit a novel plastic stretching mechanism of anisotropy, whereby the fast direction in snow aligns with accelerating ice shelf flow.
A Woman’s Place Is at the Negotiating Table: Evidence from Colombian Peace Processes
Authors: Gillooly Shauna N.
Published: December 2022

A substantial amount of scholarly work has been conducted on considerations (or lack thereof) of gender in the context of peace negotiations. While gender-specific concerns, particularly those focused on women’s empowerment, are now emphasized in the language of international and national organizations involved in peacebuilding (e.g., UN Security Council Resolution 1325), many times this language is just “talk.” Often, on-the-ground practice and policy does not reflect the lived experiences of women in post-accord or transitional contexts. This article analyzes the change in roles and the roles available to women in pre-negotiation and framework-setting negotiation processes between the Colombian government and nonstate armed actors. The study examines the negotiations between the Colombian government under the Juan Manuel Santos administration and the Fuerzas Armadas Revolucionarios de Colombia (FARC) in 2012–2016 to interrogate the ways that women, feminist groups, and women’s organizations play a role in pre-negotiation processes.
Stratigraphic evidence for culturally variable Indigenous fire regimes in ponderosa pine forests of the Mogollon Rim area, east-central Arizona
Authors: Roos Christopher I. , Laluk Nicholas C. , Reitze William , Davis Owen K.
Published: December 2022

The impact of Indigenous populations on historical fire regimes has been controversial and beset by mismatches in the geographic scale of paleofire reconstructions and the scale of land-use behaviors. It is often assumed that anthropogenic burning is linearly related to population density and not different cultural practices. Here we take an off-site geoarchaeology strategy to reconstruct variability in historical fire regimes (<1000 years ago) at geographic scales that match the archaeological, ethnohistorical, and oral tradition evidence for variability in the intensity of Indigenous land use by two different cultural groups (Ancestral Pueblo and Western Apache). We use multiple, independent proxies from three localities in ponderosa pine (Pinus ponderosa) forests in east-Central Arizona to reconstruct fire regime variability during four phases of cultural use of different intensities. Elevated charcoal with domesticate pollen (Zeaspp.) but otherwise unchanged forest pollen assemblages characterized intensive land use by Ancestral Pueblo people during an early phase, suggesting fire use to support agricultural activities. By contrast, a phase of intensive pre-reservation Western Apache land use corresponded to little change in charcoal, but had elevated ash-derived phosphorus and elevated grass and ruderal pollen suggestive of enhanced burning in fine fuels to promote economically important wild plants.
Commercial television and primate ethology: facial expressions between Granada and London Zoo
Authors: Kempton Miles
Published: December 2022

This article examines the significant relationship that existed between commercial British television and the study of animal behaviour. Ethological research provided important content for the new television channel, at the same time as that coverage played a substantial role in creating a new research specialism, the study of primate facial expressions, for this emergent scientific discipline. The key site in this was a television and film unit at London Zoo administered by the Zoological Society and Granada TV. The Granada unit produced ‘Animal expressions’, a twenty-five-minute television film based on research on monkeys and apes by the Dutch postgraduate student and soon-to-be-leading-authority Jan van Hooff. Recovering the production and multiple uses of ‘Animal expressions’, this paper offers the first sustained historical analysis of science on commercial television. I show how Granada patronage helped Van Hooff to support his argument that human expressions such as smiling and laughter shared common evolutionary origins with similar facial movements in nonhuman primates. Emphasizing the mutual shaping of science and ITV, I argue that ‘Animal expressions’ repurposed televisual conventions of framing talking heads, and blended serious science with the comedy of ‘funny faces’, thereby epitomizing Granada's public-service strategy at a time when commercial television was defending itself from criticism in the Pilkington report.
Does Pten have an impact on oogenesis of PCOS mouse models?
Authors: Onal T. , Tulay P. , Vatansever H.S.
Published: December 2022

Polycystic ovary syndrome (PCOS) is a complex disorder in which the aetiology is still not explained very well. The PI3K/PTEN (phosphatidylinositol 3-kinase/phosphatase and tensin homolog deleted on chromosome 10) pathway is an important pathway that is involved in many mechanisms, including proliferation, growth and motility. PTEN plays a role in granulosa cell proliferation and regulates the differentiation process. The aim of this study was to investigate the expression levels of Pten and Pik3ca in PCOS mouse models with and without any treatment procedures. Three groups of mouse models, PCOS, a PCOS group with clomiphene citrate treatment, and a PCOS group with the combination of clomiphene citrate, metformin and pioglitazone treatment, were established. Ovarian tissues, which were obtained from these groups and a control group with no PCOS, were embedded in paraffin and RNA was extracted. cDNA was synthesized and real-time PCR was conducted to evaluate the expression levels of Pten and Pik3ca. The results of this study showed that both Pten and Pik3ca genes were expressed in the ovarian tissues from the mouse models. Although one-way analysis of variance results showed that Pten was expressed significantly differently in the samples, individual Student’s t-tests did not show any significantly different expression levels in each group. This study is important as it shows the expression patterns of two genes in PCOS mouse models with different treatment strategies, including clomiphene citrate, metformin and pioglitazone. The results of this study formed the basis of research studies and investigations into different genes within the PTEN pathway, as well as other pathways that are under investigation.
Late systemic desaturation after transcatheter device closure of atrial septal defect
Authors: Bagaria Vivek , Hiremath Channabasavaraj S.
Published: December 2022

Transcatheter device closure has emerged as the preferred treatment for ostium secundum atrial septal defects with adequate margins, occasionally requiring surgical intervention to manage complications. We report a case of a young female patient who presented with systemic desaturation and exertional dyspnoea 5 years after device closure. Evaluation demonstrated anterior malposition of the septal occluder, with the right atrial rim of the device diverting the blood from the inferior vena cava to the left atrium. She underwent surgical extraction of the device and pericardial patch closure of the atrial septal defect.
“A Voyage of Discovery”: Reimagining the Walking Woman through Nineteenth-Century Diaries
Authors: Bredar Trish
Published: December 2022

This article uses a corpus of manuscript diaries to illuminate the practices and meanings of everyday mobility that shaped the lives of nineteenth-century Englishwomen. The female pedestrian has typically been characterized by scholars as a marginal or transgressive figure whose movements are interpreted through comparison to a masculine peripatetic tradition. “A Voyage of Discovery” seeks to broaden our understanding of what it meant to move through the world as a woman in the nineteenth century. Drawing from the narrated experiences of a broad range of little-known diarists, this article outlines a paradigm of “everyday adventure” to describe walking's status as an unremarkable act that nevertheless creates the potential for event and variety. In so doing, it expands on feminist concepts of the everyday, elaborates on the under-theorized relationship between walking and the body, and reassesses the boundaries of socially acceptable mobility.
Catching Up with the West? Historiographical stances in early accounts of Chinese electronic music
Authors: Liu Annie Yen-Ling
Published: December 2022

The emergence of electroacoustic music in China began much more recently than in Europe, the United States, North America, and Japan. Scholars have located the mid-1980s as the turning point in this development. Although consensus is lacking about the exact events and influences that initiated this field of musical production, a pervasive issue confronting historiographical scholarship has been the belatedness of this production. Linked to the trope of belatedness is an acknowledgement of the extremely rapid development of Chinese electroacoustic music, which both assimilated Western technologies and asserted distinctive national characteristics. Furthermore, one of the pioneers in the field, Zhang Xiaofu, has argued that a distinctive ‘Chinese model’ of electroacoustic music marked by stylistic hybridity and integration quickly emerged after this inception. The resulting ‘syncretism’ of practices has generated extensive reflection among Chinese composers and critics.
Fall-sown small grain cover crops for weed suppression and soil moisture management in an irrigated organic agroecosystem
Authors: Pratt Richard C. , Schutte Brian J. , Idowu O. John , Uchanski Mark , Grant Lois
Published: December 2022

Adoption of cover crops in arid agroecosystems has been slow due to concerns regarding limited water resources and possible soil moisture depletion. In irrigated organic systems, potential ecosystem services from cover crops also must be considered in light of the concerns for water conservation. A constructive balance could be achieved with fall-sown small grain cover crops; however, their impacts on irrigated organic systems are poorly understood. Our first objective was to determine the ability of fall-sown small grains [cereal rye (Secale cereale L), winter wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and oat (Avena sativa L.)] to suppress winter weeds in an irrigated, organic transition field in the southwestern USA. Small grains were planted following the legume sesbania (Sesbania exaltata (Raf.) Rydb. ex A.W. Hill) during Fall 2012 and Fall 2013. In Spring 2013 and 2014, weed densities and biomass were determined within each cover crop treatment and compared against unplanted controls. Results indicated that both barley and oat were effective in suppressing winter weeds. Our second objective was to compare weed suppression and soil moisture levels among seven barley varieties developed in the western United States. Barley varieties (‘Arivat’, ‘Hayes Beardless’, ‘P919’, ‘Robust’, ‘UC603’, ‘UC937’, ‘Washford Beardless’) were fall-sown in replicated strip plots in Fall 2016. Weed densities were measured in Spring 2017 and volumetric soil moisture near the soil surface (5.1 cm depth) was measured at time intervals beginning in December 2016 and ending in March 2017. With the exception of ‘UC937’, barley varieties caused marked reductions in weed density in comparison with the unplanted control. Soil moisture content for the unplanted control was consistently lower than soil moisture contents for barley plots. Barley variety did not influence volumetric soil moisture. During the 2017–2018 growing season, we re-examined three barley varieties considered most amenable to the cropping system requirements (‘Robust’, ‘UC603’, ‘P919’), and these varieties were again found to support few weeds (≤ 5.0 weeds m−2). We conclude that several organically certified barley varieties could fill the need for a ‘non-thirsty’ cover crop that suppresses winter weeds in irrigated organic systems in the southwestern United States.
Basking in Their Glory? Expressive Partisanship among People of Color Before and After the 2020 US Election
Authors: Maxwell Rahsaan , Pérez Efrén , Zonszein Stephanie
Published: December 2022

As the number of people of color (PoC) grows in the United States, a key question is how partisanship will develop among this important electoral group. Yet many open questions remain about PoC partisanship, due to limited availability of panel data, a lack of sensitive instrumentation, and small samples of PoC in most public opinion surveys. This brief report leverages a unique panel of African American (N = 650) and Latino (N = 650) eligible voters, before and after the 2020 Presidential Election between Democrat Joe Biden and Republican Donald Trump. Using measures that tap expressive partisan, racial, and national identity attachments, we find that Biden’s electoral victory significantly intensified partisan identity among his Democratic PoC supporters, relative to PoC who were not Democrats and supported Trump. We do not find significant changes in racial or national identities. Our results advance research on PoC’s partisanship.
MAVEN/NGIMS Dayside Exospheric Temperatures Over Solar Cycle and Seasons: Role of Dayside Thermal Balances in Regulating Temperatures
Authors: Bougher S. W. , Benna M. , Elrod M. , Roeten K. , Thiemann E.
Published: December 2022

Several important processes of the Mars upper atmosphere are regulated by exospheric temperature (Texo) variations, including atmospheric escape rates. From the MAVEN mission, significant and largely periodic variability of Mars dayside Texo is now revealed by Neutral Gas and Ion Mass Spectrometer (NGIMS) data sets collected throughout solar cycle 24. Two complementary methods are utilized to extract temperatures from NGIMS data sets. These NGIMS dayside mean exospheric temperatures are shown to vary by ∼80 K (∼180–260 K) over solar cycle 24. This corresponds to a ΔTexo/ΔEUV sensitivity of ∼38 K m2 mW−1, where Lyman‐α is the solar index. Previous Mars Global Surveyor derived Texo values for solar cycle 23 yielded a sensitivity of ∼45 in the same units. This close correspondence suggests that the underlying dayside energy balances are similar yet slightly different over these two solar cycles. Corresponding Mars Global Ionosphere‐Thermosphere Model simulations show that molecular thermal conduction largely balances EUV heating for the Mars dayside thermosphere, while CO2 15‐µm cooling is secondary in importance, along with global winds. It is valuable to compare this Mars sensitivity to that computed for the dayside thermosphere of Venus. Pioneer Venus dayside data sets imply a sensitivity of ∼17.5 K m2 mW−1 units for solar cycle 21, a factor of ∼2.2 smaller than computed for Mars. This is because Venus CO2 cooling strongly balances EUV heating near its peak, thereby serving as a more efficient thermostat regulating dayside temperatures. CO2 cooling is much weaker for Mars.
The Spatiotemporal Variability of Snowpack and Snowmelt Water 18O and 2H Isotopes in a Subarctic Catchment
Authors: Noor Kashif , Marttila Hannu , Klöve Björn , Welker Jeffrey M. , Ala‐aho Pertti
Published: December 2022

This study provides a detailed characterization of spatiotemporal variations of stable water 18O and 2H isotopes in both snowpack and meltwater in a subarctic catchment. We performed extensive sampling and analysis of snowpack and meltwater isotopic compositions at 11 locations in 2019 and 2020 across three different landscape features: (a) forest hillslope, (b) mixed forest, and (c) open mires. The vertical isotope profiles in the snowpack's layered stratigraphy presented a consistent pattern in all locations before snowmelt, and isotope profiles homogenized during the peak melt period; represented by a 1–2‰ higher 18O value than prior to melting. Our data indicated that the liquid‐ice fractionation was the prime reason that caused the depletion of heavy isotopes in initial meltwater samples prior to the peak melt period. The liquid‐ice fractionation was influenced by snowmelt rate, with higher fractionation during slow melt. The kinetic liquid‐ice fractionation was evident only in close examination of meltwater lc‐excess values, not 18O values alone. Meltwater was isotopically heavier and more variable than the depth‐integrated snowpack; the weighted mean of meltwater isotope values was higher by 0.62–1.33‰ 18O than the weighted mean of snowpack isotope values in forest hillslope and mixed forest areas, and 1.51–6.37‰ 18O in open mires. Our results reveal close to 3.1‰ 18O disparity between the meltwater and depth‐integrated snowpack isotope values prior to the peak melt period, suggesting that proper characterization of meltwater 18O and 2H values is vital for tracer‐based ecohydrological studies and models.
Endothelial cells regulate astrocyte to neural progenitor cell trans-differentiation in a mouse model of stroke
Authors: Li Wenlu , Mandeville Emiri T. , Durán-Laforet Violeta , Fukuda Norito , Yu Zhanyang , Zheng Yi , Held Aaron , Park Ji-Hyun , Nakano Takafumi , Tanaka Masayoshi , Shi Jingfei , Esposito Elga , Niu Wanting , Xing Changhong , Hayakawa Kazuhide , Lizasoain Ignacio , van Leyen Klaus , Ji Xunming , Wainger Brian J. , Moro Maria A. , Lo Eng H.
Published: December 2022

The concept of the neurovascular unit emphasizes the importance of cell-cell signaling between neural, glial, and vascular compartments. In neurogenesis, for example, brain endothelial cells play a key role by supplying trophic support to neural progenitors. Here, we describe a surprising phenomenon where brain endothelial cells may release trans-differentiation signals that convert astrocytes into neural progenitor cells in male mice after stroke. After oxygen-glucose deprivation, brain endothelial cells release microvesicles containing pro-neural factor Ascl1 that enter into astrocytes to induce their trans-differentiation into neural progenitors. In mouse models of focal cerebral ischemia, Ascl1 is upregulated in endothelium prior to astrocytic conversion into neural progenitor cells. Injecting brain endothelial-derived microvesicles amplifies the process of astrocyte trans-differentiation. Endothelial-specific overexpression of Ascl1 increases the local conversion of astrocytes into neural progenitors and improves behavioral recovery. Our findings describe an unexpected vascular-regulated mechanism of neuroplasticity that may open up therapeutic opportunities for improving outcomes after stroke.
The tongue biofilm metatranscriptome identifies metabolic pathways associated with the presence or absence of halitosis
Authors: Carda-Diéguez M. , Rosier B.T. , Lloret S. , Llena C. , Mira A.
Published: December 2022

Intra-oral halitosis usually results from the production of volatile sulfur compounds, such as methyl mercaptan and hydrogen sulfide, by the tongue microbiota. There are currently no reports on the microbial gene-expression profiles of the tongue microbiota in halitosis. In this study, we performed RNAseq of tongue coating samples from individuals with and without halitosis. The activity of Streptococcus (including S. parasanguinis), Veillonella (including V. dispar) and Rothia (including R. mucilaginosa) was associated with halitosis-free individuals while Prevotella (including P. shahi), Fusobacterium (including F. nucleatum) and Leptotrichia were associated with halitosis. Interestingly, the metatranscriptome of patients that only had halitosis levels of methyl mercaptan was similar to that of halitosis-free individuals. Finally, gene expression profiles showed a significant over-expression of genes involved in L-cysteine and L-homocysteine synthesis, as well as nitrate reduction genes, in halitosis-free individuals and an over-expression of genes responsible for cysteine degradation into hydrogen sulfide in halitosis patients.
A phase I clinical study to assess safety and immunogenicity of yellow fever vaccine
Authors: Desai Sajjad , Anil K. , Potey Anirudha Vyankatesh , Sindhu Y. , Grappi Silvia , Lapini Giulia , Manney Satyaprasad , Tyagi Parikshit , Montomoli Emanuele , Poonawalla Cyrus S. , Kulkarni Prasad S.
Published: December 2022

Yellow fever, a mosquito-borne flavivirus infection, is an important public health problem in Africa and Latin America. A Yellow Fever vaccine (YFV) was developed and tested in a study in India. This was a Phase I, open-label, randomized, controlled study where healthy adults received SII YFV intramuscularly (SII YFV IM), SII YFV subcutaneously (SII YFV SC) or STAMARIL® (Sanofi-Pasteur) in 1:1:1 ratio. They were followed for solicited reactions for 10 days and unsolicited events for 28 days and serious adverse events for 3 months. YF-neutralizing antibodies were measured at baseline and on Days 10, 14, 28. A total of 60 adults were enrolled in the study. The proportion of participants with solicited reactions was 10%, 40%, and 25% in SII YFV SC, SII YFV IM, and STAMARIL® arms, respectively. No causally related unsolicited events or any serious adverse event was reported. After vaccination, the seroconversion was 94.44%, 100%, and 100%, in the three arms respectively. The post-vaccination geometric mean titers were similar in the study arms. The new YFV was found safe and immunogenic by IM as well as SC routes. The vaccine can be tested in further phases of clinical studies.
Challenges and developments in universal vaccine design against SARS-CoV-2 variants
Authors: Zhao Fangxin , Zai Xiaodong , Zhang Zhiling , Xu Junjie , Chen Wei
Published: December 2022

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had become a global concern because of its unexpectedly high pathogenicity and transmissibility. SARS-CoV-2 variants that reduce the immune protection elicited from previous vaccination or natural infection raise challenges in controlling the spread of the pandemic. The development of universal vaccines against these variants seems to be a practical solution to alleviate the physical and economic effects caused by this disease, but it is hard to achieve. In this review, we describe the high mutation rate of RNA viruses and dynamic molecular structures of SARS-CoV-2 variants in several major neutralizing epitopes, trying to answer the question of why universal vaccines are difficult to design. Understanding the biological basis of immune evasion is crucial for combating these obstacles. We then summarize several advancements worthy of further study, including heterologous prime-boost regimens, construction of chimeric immunogens, design of protein nanoparticle antigens, and utilization of conserved neutralizing epitopes. The fact that some immunogens can induce cross-reactive immune responses against heterologous coronaviruses provides hints for universal vaccine development. We hope this review can provide inspiration to current universal vaccine studies.
Epipelagic nitrous oxide production offsets carbon sequestration by the biological pump
Authors: Wan Xianhui S. , Sheng Hua-Xia , Dai Minhan , Casciotti Karen L. , Church Matthew J. , Zou Wenbin , Liu Li , Shen Hui , Zhou Kuanbo , Ward Bess B. , Kao Shuh-Ji
Published: December 2022

The removal of carbon dioxide from the atmosphere by the marine biological pump is a key regulator of Earth’s climate; however, the ocean also serves as a large source of nitrous oxide, a potent greenhouse gas and ozone-depleting substance. Although biological carbon sequestration and nitrous oxide production have been individually studied in the ocean, their combined impacts on net greenhouse forcing remain uncertain. Here we show that the magnitude of nitrous oxide production in the epipelagic zone of the subtropical ocean covaries with remineralization processes and thus acts antagonistically to weaken the radiative benefit of carbon removal by the marine biological pump. Carbon and nitrogen isotope tracer incubation experiments and nitrogen isotope natural abundance data indicate enhanced biological activity promotes nitrogen recycling, leading to substantial nitrous oxide production via both oxidative and reductive pathways. These shallow-water nitrous oxide sources account for nearly half of the air–sea flux and counteract 6–27% (median 9%) of the greenhouse warming mitigation achieved by carbon export via the biological pump.
Ultrafast serrodyne optical frequency translator
Authors: Balla Prannay , Tünnermann Henrik , Salman Sarper H. , Fan Mingqi , Alisauskas Skirmantas , Hartl Ingmar , Heyl Christoph M.
Published: December 2022

The serrodyne principle enables an electromagnetic signal to be frequency shifted by applying a linear phase ramp in the time domain. This phenomenon has been exploited to frequency shift signals in the radiofrequency, microwave and optical regions of the electromagnetic spectrum over ranges of up to a few gigahertz, for example, to analyse the Doppler shift of radiofrequency signals for noise suppression and frequency stabilization. Here we employ this principle to shift the centre frequency of high-power femtosecond laser pulses over a range of several terahertz with the help of a nonlinear multi-pass cell. We demonstrate our method experimentally by shifting the central wavelength of a state-of-the-art 75 W frequency comb laser from 1,030 nm to 1,060 nm and to 1,000 nm. Furthermore, we experimentally show that this wavelength-shifting technique supports coherence characteristics at the few hertz-level while improving the temporal pulse quality. The technique is generally applicable to wide parameter ranges and different laser systems, enabling efficient wavelength conversion of high-power lasers to spectral regions beyond the gain bandwidth of available laser platforms.
Profound phenotypic and epigenetic heterogeneity of the HIV-1-infected CD4+ T cell reservoir
Authors: Wu Vincent H. , Nordin Jayme M. L. , Nguyen Son , Joy Jaimy , Mampe Felicity , del Rio Estrada Perla M. , Torres-Ruiz Fernanda , González-Navarro Mauricio , Luna-Villalobos Yara Andrea , Ávila-Ríos Santiago , Reyes-Terán Gustavo , Tebas Pablo , Montaner Luis J. , Bar Katharine J. , Vella Laura A. , Betts Michael R.
Published: December 2022

Understanding the complexity of the long-lived HIV reservoir during antiretroviral therapy (ART) remains a considerable impediment in research towards a cure for HIV. To address this, we developed a single-cell strategy to precisely define the unperturbed peripheral blood HIV-infected memory CD4+ T cell reservoir from ART-treated people living with HIV (ART-PLWH) via the presence of integrated accessible proviral DNA in concert with epigenetic and cell surface protein profiling. We identified profound reservoir heterogeneity within and between ART-PLWH, characterized by new and known surface markers within total and individual memory CD4+ T cell subsets. We further uncovered new epigenetic profiles and transcription factor motifs enriched in HIV-infected cells that suggest infected cells with accessible provirus, irrespective of reservoir distribution, are poised for reactivation during ART treatment. Together, our findings reveal the extensive inter- and intrapersonal cellular heterogeneity of the HIV reservoir, and establish an initial multiomic atlas to develop targeted reservoir elimination strategies.
Datasets of a Multizone Office Building under Different HVAC System Operation Scenarios
Authors: Yoon Yeobeom , Jung Sungkyun , Im Piljae , Gehl Anthony
Published: December 2022

This study provides an open-source dataset of the measured weather data, building indoor data, and system data under the different test settings. The test building is the two-story Flexible Research Platform building at the US Department of Energy’s Oak Ridge National Laboratory, in Oak Ridge, Tennessee. Four heating tests and three cooling tests were conducted. The 1-min interval of weather, building indoor data, and system data from each test setting are provided. Actual weather data were collected from a weather station installed on the roof. This paper describes information on the test building and installed sensors, data collection method, and data validation. The provided dataset can be employed to understand HVAC system conditions and building indoor conditions under different HVAC system operations and the performance of building envelope without HVAC system operation using free-floating test data. Additionally, it can be used for empirical validation of the building energy modelling engine.
Global patterns of prognostic biomarkers across disease space
Authors: Murad Neha , Melamud Eugene
Published: December 2022

There is a multitude of pathological conditions that affect human health, yet we currently lack a predictive model for most diseases, and underlying mechanisms that are shared by multiple diseases are poorly understood. We leveraged baseline clinical biomarker data and long-term disease outcomes in UK Biobank to build prognostic multivariate survival models for over 200 most common diseases. We construct a similarity map between biomarker-disease hazard ratios and demonstrate broad patterns of shared similarity in biomarker profiles across the entire disease space. Further aggregation of risk profiles through density based clustering showed that biomarker-risk profiles can be partitioned into few distinct clusters with characteristic patterns representative of broad disease categories. To confirm these risk patterns we built disease co-occurrence networks in the UK Biobank and US HCUP hospitalization databases, and compared similarity in biomarker risk profiles to disease co-occurrence. We show that proximity in the biomarker-disease space is strongly related to the occurrence of disease comorbidity, suggesting biomarker profile patterns can be used for both predicting future outcomes as well as a sensitive mechanism for detecting under-diagnosed disease states.
Metabolomics analysis of plasma samples of patients with fibromyalgia and electromagnetic sensitivity using GC–MS technique
Authors: Piras Cristina , Pibiri Monica , Conte Stella , Ferranti Gabriella , Leoni Vera Piera , Liggi Sonia , Spada Martina , Muntoni Sandro , Caboni Pierluigi , Atzori Luigi
Published: December 2022

Fibromyalgia (FM) is a chronic and systemic condition that causes widespread chronic pain, asthenia, and muscle stiffness, as well as in some cases depression, anxiety, and disorders of the autonomic system. The exact causes that lead to the development of FM are still unknown today. In a percentage of individuals, the symptoms of FM are often triggered and/or exacerbated by proximity to electrical and electromagnetic devices. Plasma metabolomic profile of 54 patients with fibromyalgia and self-reported electromagnetic sensitivity (IEI-EMF) were compared to 23 healthy subjects using gas chromatography-mass spectrometry (GC–MS) coupled with multivariate statistical analysis techniques. Before the GC–MS analysis the plasma samples were extracted with a modified Folch method and then derivatized with methoxamine hydrochloride in pyridine solution and N-trimethylsilyltrifuoroacetamide. The combined analysis allowed to identify a metabolomic profile able of distinguishing IEI-EMF patients and healthy subjects. IEI-EMF patients were therefore characterized by the alteration of 19 metabolites involved in different metabolic pathways such as energy metabolism, muscle, and pathways related to oxidative stress defense and chronic pain. The results obtained in this study complete the metabolomic "picture" previously investigated on the same cohort of IEI-EMF patients with1H-NMR spectroscopy, placing a further piece for better understanding the pathophysiological mechanisms in patients with IEI-EMF.