bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypothesis on the pathophysiology of syringomyelia based on analysis of phase-contrast magnetic resonance imaging of Chiari-I malformation patients
Authors: Chang Han Soo 
Published: October 2021

Background: Despite a number of hypotheses, our understanding of the pathophysiology of syringomyelia is still limited. The current prevailing hypothesis assumes that the piston-like movement of the cerebellar tonsils drives the cerebrospinal fluid (CSF) into the syrinx through the spinal perivascular space. However, it still needs to be verified by further experimental data. A major unexplained problem is how CSF enters and remains in the syrinx that has a higher pressure than the subarachnoid space. Methods: I analyzed phase-contrast MRI scans of 18 patients with Chiari-I malformation with syringomyelia undergoing foramen magnum decompression and 21 healthy volunteers. I analyzed the velocity waveforms of the CSF and the brain in various locations. The obtained velocity waveforms were post-processed using a technique called synchronization in situ. I compared between the preoperative data and the control data (case-control study), as well as between the preoperative and postoperative data (cohort study). Results: The syrinx shrank in 17 (94%) patients with good clinical improvement. In Chiari-I patients, the velocity of the tonsil was significantly larger than controls, but was significantly smaller than that of the CSF in the subarachnoid space, suggesting passive rather than active movement. The abnormal tonsillar movement disappeared after surgery, but the velocity waveform of the spinal subarachnoid CSF did not change. These results, contradicting the above mentioned hypothesis, required an alternative explanation. I thus hypothesized that there is a CSF channel between the fourth ventricle and the syrinx. This channel assumes one-way valve function when mildly compressed by the cyclical movement of the cerebellar tonsil. The decompression of the tonsils switches off the one-way valve, collapsing the syrinx. Conclusions: My hypothesis reasonably explained my data that clearly contradicted the existing hypothesis, and successfully addressed the above-mentioned theoretical problem. It will serve as a working hypothesis for further study of syringomyelia pathophysiology.
Performance evaluation of a multinational data platform for critical care in Asia
Authors:   Collaboration for Research, Implementation and Training in Critical Care - Asia Investigators, Pisani Luigi , Rashan Thalha , Shamal Maryam , Ghose Aniruddha , Kumar Tirupakuzhi Vijayaraghavan Bharath , Tripathy Swagata , Aryal Diptesh , Hashmi Madiha , Nor Basri , Lam Minh Yen , Dondorp Arjen M. , Haniffa Rashan , Beane Abi 
Published: October 2021

Background: The value of medical registries strongly depends on the quality of the data collected. This must be objectively measured before large clinical databases can be promoted for observational research, quality improvement, and clinical trials. We aimed to evaluate the quality of a multinational intensive care unit (ICU) network of registries of critically ill patients established in seven Asian low- and middle-income countries (LMICs). Methods: The Critical Care Asia federated registry platform enables ICUs to collect clinical, outcome and process data for aggregate and unit-level analysis. The evaluation used the standardised criteria of the Directory of Clinical Databases (DoCDat) and a framework for data quality assurance in medical registries. Six reviewers assessed structure, coverage, reliability and validity of the ICU registry data. Case mix and process measures on patient episodes from June to December 2020 were analysed. Results: Data on 20,507 consecutive patient episodes from 97 ICUs in Afghanistan, Bangladesh, India, Malaysia, Nepal, Pakistan and Vietnam were included. The quality level achieved according to the ten prespecified DoCDat criteria was high (average score 3.4 out of 4) as was the structural and organizational performance -- comparable to ICU registries in high-income countries. Identified strengths were types of variables included, reliability of coding, data completeness and validation. Potential improvements included extension of national coverage, optimization of recruitment completeness validation in all centers and the use of interobserver reliability checks. Conclusions: The Critical Care Asia platform evaluates well using standardised frameworks for data quality and equally to registries in resource-rich settings.
How Does Deleveraging Affect Funding Market Liquidity?
Authors: Qiu Buhui , Tian Gary Gang , Zeng Haijian 
Published: October 2021

How does deleveraging affect the market liquidity of high-embedded-leverage securities issued by financial institutions and the funding constraints of these institutions? We use the forced deleveraging of structured mutual funds during the 2015 Chinese stock market crash to study the effects of deleveraging. Our regression-discontinuity analysis shows that deleveraging significantly reduces the market liquidity of the deleveraging funds’ equity units. Moreover, our difference-in-differences analysis shows that deleveraging results in large decreases in subsequent fund flows, stock and cash holdings, and performance, with the impact channeled through the deterioration of the market liquidity of the fund’s equity units. This paper was accepted by Victoria Ivashina, finance.
The Role of Participation in Innovation Contests
Authors: Stouras Konstantinos I. , Hutchison-Krupat Jeremy , Chao Raul O. 
Published: October 2021

Many firms use external contests to obtain solutions to their innovation challenges. A central managerial concern is how to screen the population for only the most capable people when the capability of the population is not known. If the manager sets the bar too high, then the contest could fail, leaving the firm to suffer the consequences. Alternatively, if the bar is set too low, then too many people enter, which leads to increased competition, a lack of effort, and diminished performance, again leaving the firm to suffer the consequences. We study a situation in which the number of solvers in a population is known but the ability of each individual is not. At best, the firm can deduce the probability that any number of solvers would enter and the probability that any solver who enters would possess a specific ability. We derive the optimal contest design to maximize the performance of the best submission while accounting for the possibility that the contest receives an insufficient number of entries, resulting in an unproductive contest. Our results provide an alternative rationale for why many contests offer multiple awards: firms want to avoid an unproductive contest and the negative consequences associated with it. We also consider alternative levers available to the firm when facing uncertain participation. These include the establishment of performance thresholds and the decision to expand the potential solver population. This paper was accepted by Charles Corbett, operations management.
Computing Large Market Equilibria Using Abstractions
Authors: Kroer Christian , Peysakhovich Alexander , Sodomka Eric , Stier-Moses Nicolas E. 
Published: October 2021

Computing market equilibria is an important practical problem for market design, for example, in fair division of items. However, computing equilibria requires large amounts of information, often the valuation of every buyer for every item, and computing power. In “Computing Large Market Equilibria Using Abstractions,” the authors study abstraction methods for ameliorating these issues. The basic abstraction idea is as follows. First, construct a coarsened abstraction of a given market, then solve for the equilibrium in the abstraction, and finally, lift the prices and allocations back to the original market. The authors show theoretical guarantees on the solution quality obtained via this approach. Then, two abstraction methods of interest for practitioners are introduced: (1) filling in unknown valuations using techniques from matrix completion and (2) reducing the problem size by aggregating groups of buyers/items into smaller numbers of representative buyers/items and solving for equilibrium in this coarsened market.
Development of a porcine hard-to-heal wound model: evaluation of a bromelain-based enzymatic debriding agent
Authors: Shoham Yaron , Sabbag Itai , Singer Adam J 
Published: October 2021

Aims: We describe the development of a novel porcine eschar model and compare the debridement efficacy of various concentrations of a novel bromelain-based enzymatic agent with collagenase. Methods: Full thickness excisional wounds were created on pigs and injected intradermally with various doses of doxorubicin. Wounds were monitored for a period of 46 days for the development of eschar and wound closure. After determining the optimal concentration and dose of doxorubicin resulting in non-healing eschars, these conditions were used to create additional wounds on another set of animals. The resulting eschars were treated with various concentrations of a novel bromelain-based enzymatic agent (EscharEx-02) or collagenase. The primary endpoint was greater than 95% removal of the central eschar. Results: Consistent eschars composed of two distinct areas (a central area of exudate and slough representing the hard-to-heal wound bed, and a peripheral area of full-thickness mummified necrosis) were seen after injection of doxorubicin (0.5 ml/cm2 of stock solution 0.75mg/ml) at one and six days after wound creation. Complete removal of the central eschar was achieved in all wounds after five and eight treatments with 5% and 2% EscharEx-02 respectively. Complete removal of the central eschar with collagenase was achieved in 0% and 82% of the wounds after 10 and 16 treatments respectively. Conclusions: We describe a porcine model for creating eschars similar to hard-to-heal wounds in humans. A novel bromelain-based enzymatic debridement agent was more effective than a commercially available collagenase in removing eschars in this wound model.
Broadband achromatic metalens for linearly polarized light from 450 to 800  nm
Authors: Liu Mian , Cao Jianjun , Xu Nianxi , Wang Ben-Xin 
Published: October 2021

Metalens is a planar optical component that uses nanostructures with a thickness on the
order of the wavelength to manipulate the wavefront of the incident
light. A key problem, especially in color imaging and display
applications, is the correction of chromatic aberration, which is an
inherent effect caused by the dispersion of periodic lattices and
resonance modes. However, the current achromatic metalenses either use
the PB phase method that is only valid for circularly polarized light
or nanostructures with complex cross sections that are difficult to
manufacture. Here, we designed a broadband achromatic metalens for
linearly polarized light from 450 to 800 nm. Rectangular titanium
dioxide nanofins of various lengths and widths were applied to
modulate the phase and dispersion of the incident light. The metalens
can fulfill three target phases simultaneously by using an
optimization method. The designed metalens has a stable focus from 450
to 800 nm with an average focusing efficiency of 64%. It can be
potentially applied in microscopes, lithography machines, sensors, and
displays.
COVID-19-related outcomes in immunocompromised patients: A nationwide study in Korea
Authors: Baek Moon Seong , Lee Min-Taek , Kim Won-Young , Choi Jae Chol , Jung Sun-Young 
Published: October 2021

BackgroundGiven the rapid increased in confirmed coronavirus disease 2019 (COVID-19) and related mortality, it is important to identify vulnerable patients. Immunocompromised status is considered a risk factor for developing severe COVID-19. We aimed to determine whether immunocompromised patients with COVID-19 have an increased risk of mortality.MethodThe groups’ baseline characteristics were balanced using a propensity score-based inverse probability of treatment weighting approach. Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated for the risks of in-hospital mortality and other outcomes according to immunocompromised status using a multivariable logistic regression model. We identified immunocompromised status based on a diagnosis of malignancy or HIV/AIDS, having undergone organ transplantation within 3 years, prescriptions for corticosteroids or oral immunosuppressants for ≥30 days, and at least one prescription for non-oral immunosuppressants during the last year.ResultsThe 6,435 COVID-19 patients (≥18 years) included 871 immunocompromised (13.5%) and 5,564 non-immunocompromised (86.5%). Immunocompromised COVID-19 patients were older (60.1±16.4 years vs. 47.1±18.7 years, absolute standardized mean difference: 0.738). The immunocompromised group had more comorbidities, a higher Charlson comorbidity index, and a higher in-hospital mortality rate (9.6% vs. 2.3%; p < .001). The immunocompromised group still had a significantly higher in-hospital mortality rate after inverse probability of treatment weighting (6.4% vs. 2.0%, p < .001). Multivariable analysis adjusted for baseline imbalances revealed that immunocompromised status was independently associated with a higher risk of mortality among COVID-19 patients (adjusted odds ratio [aOR]: 2.09, 95% CI: 1.62–2.68, p < .001).ConclusionsImmunocompromised status among COVID-19 patients was associated with a significantly increased risk of mortality.
Prevalence and risk factors of dry eye disease among University Students in Bangkok, Thailand
Authors: Supiyaphun Chantaka , Jongkhajornpong Passara , Rattanasiri Sasivimol , Lekhanont Kaevalin 
Published: October 2021

Purpose
To investigate the prevalence of dry eye disease (DED) and its associated risk factors among Thai university students.

Methods
A cross-sectional study using an electronic survey was conducted in two Rajabhat universities in Bangkok, Thailand. The woman’s health study questionnaire was used to determine students with DED. The prevalence of DED along with 95% confidence interval (CI) were calculated. Logistic regression model was used to identify the associated risk factors.

Results
A total of 4,111 university students joined and completed the survey questionnaires. Mean age was 18.8 ± 1.1 years with female predominance (2874 students, 69.91%). Clinically diagnosed DED was reported in 136 students (3.31%), while severe symptoms of eye dryness and irritation were reported in 227 students (5.52%). The prevalence of DED among Thai university students was 8.15% (95% CI 7.33% to 9.02%). History of contact lens use and high screen time (> 8 hours per day) were reported in 868 students (21.11%) and 2101 students (51.11%), respectively. Male gender, contact lens use and high screen time were significantly associated with higher risk of DED with the adjusted ORs (95% CI) of 1.39 (1.09, 1.77), 2.49 (1.96, 3.17), and 1.43 (1.14, 1.80), respectively.

Conclusions
DED is not rare among Thai university students. Contact lens use and high screen time are two significant modifiable risk factors of DED in our students. These findings can raise awareness of DED in youth population and provide valuable information for public health promotion in university students.
Effect of a hospital-wide campaign on COVID-19 vaccination uptake among healthcare workers in the context of raised concerns for life-threatening side effects
Authors: Kim Min Hyung , Son Nak-Hoon , Park Yoon Soo , Lee Ju Hyun , Kim Da Ae , Kim Yong Chan 
Published: October 2021

Background
All healthcare workers (HCWs) in Yongin Severance Hospital were allocated to receive the ChAdOx1 nCov-19 vaccine according to national policy. A report of thrombosis and thrombocytopenia syndrome (TTS) associated with ChAdOx1 nCoV-19 led to hesitancy about receiving the second dose among HCWs who had received the first dose.

Methods
From 7 to 14 May, 2021, we performed a survey to identify the factors associated with hesitancy about receiving the second vaccine dose among HCWs at the hospital who had received the first dose of the vaccine. Based on survey results, a hospital-wide campaign was implemented on 18 May 2021 to improve vaccine coverage. HCWs who completed the second dose completed a self-administered questionnaire to evaluate the effect of the campaign.

Findings
Of 1,171 HCWs who had received the first dose of the vaccine, 71.5% completed the online survey, of whom 3.7% refused to take the second dose and 22.3% showed hesitancy. Hesitancy to receive a second dose was significantly associated with age under 30 years and concerns about TTS, and was less common among those who trusted effectiveness and safety of the vaccine. Among HCWs who received the first dose, 96.2% completed vaccination with the second dose between 27 May and 4 June, 2021. Of those who answered the questionnaire asked about the timing of their decision to receive the second dose, 57.1% reported that they were motivated by the hospital-wide campaign.

Conclusion
A tailored intervention strategy based on a survey can improve COVID-19 vaccination uptake among HCWs.
Evaluación de habilidades informacionales en estudiantes universitarios de la República Dominicana
Authors: De los Santos Lorenzo Mayeily 
Published: October 2021

La Alfabetización Informacional juega un papel importante dentro del desafío que presenta la sociedad del conocimiento, por tal motivo se hace necesario formar sujetos que sean capaces de interactuar con la información en diferentes formatos; para lograr esto se necesitan proyectos de investigación que permitan dar respuestas a las necesidades actuales a través de evaluaciones que permitan conocer la situación real de las estudiantes . Esta investigación muestra los resultados de un estudio sobre el nivel de habilidades observadas en el manejo de la información de los estudiantes de educación del Instituto de Formación docente Salomé Ureña (ISFODOSU) en la República Dominica; del cual se extrajo una muestra de 347 sujetos a los que se les aplicó un cuestionario de 10 ítems sobre competencias Informacionales Observadas (CIO). Como resultados se pudo notar que los estudiantes son más competentes buscando y comunicando la información, mientras que en la dimensión de evaluación y procesamiento las medias resultaron inferiores, ya que estas implican un trabajo cognitivo complejo para los sujetos. Esta investigación contribuirá a la creación de programas dirigidos a fortalecer las necesidades evidentes de información que poseen los estudiantes, principalmente en las dimensiones donde la problemática es mayor, pudiendo ser extensivo no solo a los estudiantes de educación, sino, a otros de distintas áreas, obteniendo un alcance mayor de la población estudiantil.
O desenvolvimento do significado da relação partetodo dentro dos números racionais positivos, tendo como referência a teoria dos Campos Conceituais
Authors: Petreche Harris Sampaio Ana Carolina , Gurgel Marrey Andrea 
Published: October 2021

Este paper é fruto da investigação das autoras sobre o conhecimento dos números racionais na forma fracionária pelos alunos de 5o ano, no contexto da relação partetodo. É resultado da participação na disciplina “O ensino e aprendizagem dos números racionais” do curso de pósgraduação de Didática da Matemática, no Instituto Vera Cruz. Realizamos uma pesquisa-ação com os alunos do 5o ano da Escola Vera Cruz, no segundo semestre do ano de 2019. Partimos do material do governo de Buenos Aires, “Matemática, fracciones y números decimales 5to grado: apuntes para la enseñanza”, dirigido por Cecilia Parra, e traduzimos as propostas “Las fraciones em los repartos” e “Más repartos”, refletindo sobre a prática, analisando as diferentes estratégias e os recursos que os alunos usavam para solucionar os problemas propostos e como seus erros fazem o professor compreender a forma como estão construindo o pensamento, facilitando o planejamento do caminho a ser trilhado no ensino.
Processos de subjetivação e psicanálise: uma criança com dificuldade de aprendizagem
Authors: Oliveira dos Santos Luciana , Oliveira Souza Deia Magda , Maciel Maria Regina 
Published: October 2021

O artigo aborda os processos de subjetivação infantil e como a psicanálise lida com isso em um contexto particular, o dos problemas do aprendizado. Tem por objetivo tecer reflexões a partir de uma criança que é descrita como sofrendo de dislexia. A metodologia empregada no artigo foi o estudo teórico e a interpretação psicanalítica do que se passou nas sessões de um atendimento breve. Nesse caso clínico, havia forte aderência entre a criança e a sua família, dificultando assim seus processos de aprendizagem e singularização. Observamos que a psicoterapia funcionou como mobilizadora dos significantes que representam a criança como ser de desejo, afastando-se um diagnóstico psicopatológico. A dimensão do cuidado no campo da clínica e no espaço escolar ganhou destaque. A aproximação entre esses dois campos, apontando para o resgate do potencial criativo dos sujeitos, conclui o texto.
Trajectories of Lymphocyte Counts in the Early Phase of Acute Pancreatitis Are Associated With Infected Pancreatic Necrosis
Authors: Zhou Jing , Chen Wensong , Liu Yang , Qu Cheng , Jiang Wendi , Yin Jiangtao , Lin Jiajia , Mao Wenjian , Ye Bo , Zhou Jing , Ke Lu , Tong Zhihui , Liu Yuxiu , Li Weiqin 
Published: October 2021

INTRODUCTION:
Infected pancreatic necrosis (IPN) is an important complication of acute pancreatitis (AP). Absolute lymphocyte count (ALC) was reported to be associated with immunosuppression and the development of IPN. The aim of this study was to describe the trajectory of ALC during the early phase of AP and assess its association with IPN.

METHODS:
We retrospectively screened patients with AP admitted to our center between January 2016 and July 2019. The ALC levels for the first 7 days after admission were collected. Group-based trajectory modeling was performed to detect the trajectories. Cox proportional hazards regression model was adopted to identify potential risk factors of IPN.

RESULTS:
Overall, 292 patients were enrolled for analysis. A triple-group trajectory model was developed, assigning 116 patients to the low-level ALC group, 133 to the medium-level ALC group, and 43 to the high-level ALC group. There was no overall significant difference regarding the incidence of IPN among the 3 groups (P = 0.066). In pairwise comparison, patients in the low-level ALC group had significantly higher incidence of IPN than those in the high-level ALC group (hazard ratio: 3.50; 95% confidence interval: 1.22–10.00, P = 0.020). Length of hospital stay and intensive care unit stay differed significantly among patients with different trajectories (P = 0.042 and 0.033, respectively).

DISCUSSION:
Despite the fact that the trajectories of ALC is overall insignificant for the development of IPN, patients with persistent low ALC trajectories during the early phase of AP are more likely to develop IPN when compared with patients with high ALC trajectories.
Notes from the Editors, October 2021
Authors: The Editors - 
Published: October 2021

buy this issue
What was most significant about the published Part I of the report was that it revealed that even in the most optimistic projection of the Shared Socioeconomic Pathways—in which carbon emissions globally peak in the next four years, a 1.5°C increase in global average temperature over preindustrial levels would be avoided until 2040, and the goal of net zero carbon emissions would be reached by 2050—the consequences for global humanity would nonetheless be catastrophic by the measure of all historical precedents.