bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatially referenced Bayesian state-space model of total phosphorus in western Lake Erie
Authors: Maguire Timothy J. , Stow Craig A. , Godwin Casey M.
Published: April 2022

Abstract. Collecting water quality data across large lakes is often done under regulatory mandate; however, it is difficult to connect nutrient concentration observations to sources of those nutrients and to quantify this relationship. This difficulty arises from the spatial and temporal
separation between observations, the impact of hydrodynamic forces, and the
cost involved in discrete samples collected aboard vessels. These challenges are typified in Lake Erie, where binational agreements regulate riverine loads of total phosphorus (TP) to address the impacts from annual harmful algal blooms (HABs). While it is known that the Maumee River supplies 50 % of the nutrient load to Lake Erie, the details of how the Maumee River TP load changes Lake Erie TP concentration have not been demonstrated. We developed a hierarchical spatially referenced Bayesian state-space model with an adjacency matrix defined by surface currents. This was applied to a 2 km-by-2 km grid of nodes, to which observed lake and river TP concentrations were joined. The model generated posterior samples describing the unobserved nodes and observed nodes on unobserved days. We quantified the impact plume of the Maumee River by experimentally changing concentration data and tracking the change in in-lake predictions. Our impact plume represents the spatial and temporal variation of how river concentrations correlate with lake concentrations. We used the impact plume to scale the Maumee River spring TP load to an effective Maumee River TP spring load for each node in the lake. By assigning an effective load to each node, the relationship between load and concentration is consistent throughout our sampling locations. A linear model of annual lake node mean TP concentration and effective Maumee River load estimated that, in the absence of the Maumee River load, lake concentrations at the sampled nodes would be 23.1 µg L−1 (±1.75, 95 % CI, credible interval) and that for each 100 t of spring TP effective load delivered to Lake Erie, mean TP concentrations increase by 11 µg L−1 (±1, 95 % CI). Our proposed modeling technique allowed us to establish these quantitative connections between Maumee TP load and Lake Erie TP concentrations which otherwise would be masked by the movement of water through space and time.
Use of streamflow indices to identify the catchment drivers of hydrographs
Authors: Mathai Jeenu , Mujumdar Pradeep P.
Published: April 2022

Abstract. Time irreversibility or temporal asymmetry refers to the steeper ascending and gradual descending parts of a streamflow hydrograph. The primary goal of this study is to bring out the distinction between streamflow indices directly linked with rising limbs and falling limbs and to explore their utility in uncovering processes associated with the steeper ascending and gradual descending limbs of the hydrograph within the time-irreversibility paradigm. Different streamflow indices are correlated with the rising and falling limbs and the catchment attributes. The key attributes governing rising and falling limbs are then identified. The contribution of the work is on differentiating hydrographs by their time irreversibility features and offering an alternative way to recognize primary drivers of streamflow hydrographs. A series of spatial maps describing the streamflow indices and their regional variability in the Contiguous United States (CONUS) is introduced here. These indices complement the catchment attributes provided earlier (Addor et al., 2017) for the CAMELS data set. The findings of the study revealed that the elevation, fraction of precipitation falling as snow and depth to bedrock mainly characterize the rising limb density, whereas the aridity and frequency of precipitation influence the rising limb scale parameter. Moreover, the rising limb shape parameter is primarily influenced by the forest fraction, the fraction of precipitation falling as snow, mean slope, mean elevation, sand fraction, and precipitation frequency. It is noted that falling limb density is mainly governed by climate indices, mean elevation, and the fraction of precipitation falling as snow; however, the recession coefficients are controlled by mean elevation, mean slope, clay, the fraction of precipitation falling as snow, forest fraction, and sand fraction.
Multi-mission altimetry data to evaluate hydrodynamic model-based stage-discharge rating curves in flood-prone Mahanadi River, India
Authors: Dhote Pankaj R. , Bansal Joshal K. , Garg Vaibhav , Thakur Praveen K. , Agarwal Ankit
Published: April 2022

Abstract. River discharge and water level data play a vital role for various hydrological applications worldwide. However, limited availability of in-situ data has drawn attention towards using remote sensing techniques to monitor river flow. Indeed, multi-mission satellite altimetry data has been used to generate stage-discharge rating curves through power-law relations and empirical methods. The validation of hydrodynamic model-based rating curves is missing. We investigate the potential of available altimetry series (Jason 2, Jason 3, Saral/AltiKa, Sentinel 3A and Sentinel 3B) over Mahanadi River to validate the estimated rating curves at virtual stations. The hydrodynamic model (HEC-RAS) was developed and 07 virtual stations were identified for Mahanadi River from Boudh to Mundali Barrage. During calibration (July–October, 2018) and validation (July–October, 2018), Root Mean Square Error (RMSE) and Nash-Sutcliffe Efficiency (NSE) between simulated and in-situ water level was found to be (0.46 m, 0.83) and (0.45 m, 0.76) respectively. The calibrated and validated model was used to generate rating curves at virtual stations. The RMSE ranging between 27 cm to 88 cm was observed between simulated and altimetry water levels, specifying the potential of all the altimeters with varying specifications to validate the rating curves. The rating curves estimated at virtual stations provide a cost-effective tool for monitoring river flows at additional locations, producing discharge time series for various hydrological applications and assessing of contribution of lateral tributaries.
CALL FOR NOMINATIONS FOR NEW CO-EDITOR: STATISTICS EDUCATION RESEARCH JOURNAL
Authors: JOLLIFFE FLAVIA R. , GAL IDDO
Published: April 2022

First published May 2005 at Statistics Education Research Journal: Archives
PAST IASE CONFERENCES
Authors: JOLLIFFE FLAVIA R. , GAL IDDO
Published: April 2022

First published May 2005 at Statistics Education Research Journal: Archives
CHARACTERIZING YEAR 11 STUDENTS’ EVALUATION OF A STATISTICAL PROCESS
Authors: PFANNKUCH MAXINE
Published: April 2022

Evaluating the statistical process is considered a higher order skill and has received little emphasis in instruction. This study analyses thirty 15-year-old students’ responses to two statistics assessment tasks, which required evaluation of a statistical investigation. The SOLO taxonomy is used as a framework to develop a hierarchy of responses. Focusing on the quality of response allowed insight into and suggestions for how instruction might be improved. The implications for teaching, assessment, and the curriculum are discussed.
First published November 2005 at Statistics Education Research Journal: Archives
PRE-SERVICE ELEMENTARY SCHOOL TEACHERS’ METAPHORS FOR THE CONCEPT OF STATISTICAL SAMPLE
Authors: GROTH RANDALL E. , BERGNER JENNIFER A.
Published: April 2022

The study describes the nature of pre-service teachers’ idiosyncratic metaphors for the concept of statistical sample. These metaphors were investigated because of their potential to provide insight about individuals’ content knowledge and how that content knowledge is enacted during teaching. Personal metaphors were elicited from 54 pre-service teachers through writing prompts. The writing prompt responses revealed seven different categories of thinking. In some instances, pre-service teachers struggled to construct a metaphor for the concept of sample. In the majority of cases, they constructed a metaphor for sample and discussed its relationship to their knowledge of the concept. The categories of thinking highlight some of the aspects of the concept of sample that teacher educators need to attend to over the course of instruction, and they also point out directions for further research related to metaphorical thinking about statistical content and its interaction with teaching practice.
First published November 2005 at Statistics Education Research Journal: Archives
PAST IASE CONFERENCES
Authors: JOLLIFFE FLAVIA R. , GAL IDDO
Published: April 2022

First published November 2005 at Statistics Education Research Journal: Archives
METHODS OF LEARNING IN STATISTICAL EDUCATION: A RANDOMIZED TRIAL OF PUBLIC HEALTH GRADUATE STUDENTS
Authors: ENDERS FELICITY BOYD , DIENER-WEST MARIE
Published: April 2022

A randomized trial of 265 consenting students was conducted within an introductory biostatistics course: 69 received eight small group cooperative learning sessions; 97 accessed internet learning sessions; 96 received no intervention. Effect on examination score (95% CI) was assessed by intent-to-treat analysis and by incorporating reported participation. No difference was found by intent-to-treat analysis. After incorporating reported participation, adjusted average improvement was 1.7 points (-1.8, 5.2) per cooperative session and 2.1 points (-1.4, 5.5) per internet session after one examination. After four examinations, adjusted average improvement for four study sessions was 5.3 points (0.4, 10.3) per examination for cooperative learning and 8.1 points (3.0, 13.2) for internet learning. Consistent participation in active learning may improve understanding beyond the traditional classroom.
First published May 2006 at Statistics Education Research Journal: Archives
ELEMENTARY PRE-SERVICE TEACHERS’ CONCEPTIONS OF VARIATION IN A PROBABILITY CONTEXT
Authors: CANADA DANIEL
Published: April 2022

While other research has begun to contribute to our understanding of how pre- college students reason about variation, little has been published regarding pre- service teachers’ statistical conceptions. This paper summarizes a framework useful in examining elementary pre-service teachers’ conceptions of variation, and investigates the question of how a class of pre-service teachers’ responses concerning variation in a probability context compare from before to after class interventions. The interventions comprised hands-on activities, computer simulations, and discussions that provided multiple opportunities to attend to variation. Results showed that there was overall class improvement regarding what subjects expected and why, in that more responses after the interventions included appropriate balancing of proportional thinking along with an appreciation of variation in expressing what was likely or probable
First published May 2006 at Statistics Education Research Journal: Archives
Front pages and editorial
Authors: GAL IDDO , SHORT TOM
Published: April 2022

First published November 2006 at Statistics Education Research Journal: Archives
REASONING ABOUT DISTRIBUTION: A COMPLEX PROCESS
Authors: PFANNKUCH MAXINE , READING CHRIS
Published: April 2022

First published November 2006 at Statistics Education Research Journal Archives
THE CONCEPT OF DISTRIBUTION
Authors: WILD CHRIS
Published: April 2022

This paper is a personal exploration of where the ideas of “distribution” that we are trying to develop in students come from and are leading to, how they fit together, and where they are important and why. We need to have such considerations in the back of our minds when designing learning experiences. The notion of “distribution” as a lens through which statisticians look at the variation in data is developed. I explore the sources of variation in data, empirical versus theoretical distributions, the nature of statistical models, sampling distributions, the conditional nature of distributions used for modelling, and the underpinnings of inference.
First published November 2006 at Statistics Education Research Journal Archives
AN EMERGING HIERARCHY OF REASONING ABOUT DISTRIBUTION: FROM A VARIATION PERSPECTIVE5
Authors: READING CHRIS , REID JACKIE
Published: April 2022

Recent research into students’ reasoning about variation refers specifically to notions of distribution that emerge. This paper reports on research where written responses, from tertiary introductory statistics students, were coded according to the level of consideration of variation. A hierarchy of reasoning about distribution is proposed, based on the notions of distribution that were evident in these responses. The hierarchy reflects students’ progression from describing key elements of distribution to linking them for comparison and inference. The proposed hierarchy provides researchers with an emerging framework of students’ reasoning about distribution. The research also highlights that educators need to be aware that, without a well developed consideration of variation, students’ ability to reason about distribution will be hampered.
First published November 2006 at Statistics Education Research Journal Archives
THE ROLE OF CAUSALITY IN THE CO-ORDINATION OF TWO PERSPECTIVES ON DISTRIBUTION WITHIN A VIRTUAL SIMULATION
Authors: PRODROMOU THEODOSIA , PRATT DAVE
Published: April 2022

Our primary goal is to design a microworld which aspires to research thinking-in- change about distribution. Our premise, in line with a constructivist approach and our prior research, is that thinking about distribution must develop from causal meanings already established. This study reports on a design research study of how students appear to exploit their appreciation of causal control to construct new situated meanings for the distribution of throws and success rates. We provided on- screen control mechanisms for average and spread that could be deterministic or subject to stochastic error. The students used these controls to recognise the limitations of causality in the short term but its power in making sense of the emergence of distributional patterns. We suggest that the concept of distribution lies in co-ordinating emergent data-centric and modelling perspectives for distribution and that causality may play a central role in supporting that co-ordination process.
First published November 2006 at Statistics Education Research Journal Archives
USE OF EXTERNAL VISUAL REPRESENTATIONS IN PROBABILITY PROBLEM SOLVING
Authors: CORTER JAMES E. , ZAHNER DORIS C.
Published: April 2022

We investigate the use of external visual representations in probability problem solving. Twenty-six students enrolled in an introductory statistics course for social sciences graduate students (post-baccalaureate) solved eight probability problems in a structured interview format. Results show that students spontaneously use self- generated external visual representations while solving probability problems. The types of visual representations used include: reorganization of the given information, pictures, novel schematic representations, trees, outcome listings, contingency tables, and Venn diagrams. The frequency of use of each of these different external visual representations depended on the type of probability problem being solved. We interpret these findings as showing that problem solvers attempt to select representations appropriate to the problem structure, and that the appropriateness of the representation is determined by the problem’s underlying schema.
First published May 2007 at Statistics Education Research Journal Archives
PAST CONFERENCE
Authors: GAL IDDO , SHORT TOM
Published: April 2022

First published May 2007 at Statistics Education Research Journal Archives
EVALUATION OF DISTANCE LEARNING IN AN “INTRODUCTION TO BIOSTATISTICS” CLASS: A CASE STUDY
Authors: EVANS SCOTT R. , WANG RUI , YEH TZU-MIN , ANDERSON JEFF , HAIJA RAMMY , MCBRATNEY-OWEN PAUL MADOC , PEEPLES LYNNE , SINHA SUBIR , XANTHAKIS VANESSA , RAJICIC NATASA , ZHANG JIAMENG
Published: April 2022

Biostatistics is not universally available in colleges/universities and is thus an attractive course to offer via distance education. However, evaluation of the impact of distance education on course enrollment and student success is lacking. We evaluated an “Introduction to Biostatistics” course at Harvard University that offered the distance option (Spring 2005).We assessed the effect on course enrollment and compared the grades of traditional students with non-traditional students, as well as with historical traditional students (Fall 2004). We further compared course evaluations from the inaugural semester with the distance option to evaluations from the prior semester. No evidence of dissimilarities was noted with respect to overall course grade averages or course evaluations.
First published November 2007 at Statistics Education Research Journal: Archives
PAST IASE CONFERENCES
Authors: GAL IDDO , SHORT TOM
Published: April 2022

First published November 2007 at Statistics Education Research Journal: Archives
Front pages and editorial
Authors: PETOCZ PETER , SHORT TOM
Published: April 2022

First published May 2008 at Statistics Education Research Journal Archives
CURVILINEAR RELATIONSHIPS BETWEEN STATISTICS ANXIETY AND PERFORMANCE AMONG UNDERGRADUATE STUDENTS: EVIDENCE FOR OPTIMAL ANXIETY
Authors: KEELEY JARED , ZAYAC RYAN , CORREIA CHRISTOPHER
Published: April 2022

This study examined the possibility of a curvilinear relationship between statistics anxiety and performance in a statistics course. Eighty-three undergraduate students enrolled in an introductory course completed measures of statistics anxiety and need for achievement at seven points during the semester in conjunction with six tests. Statistics anxiety scores were reliable internally and across time. Statistics anxiety decreased during the term yet paradoxically became more strongly related to performance. Curvilinear models were better predictors of test performance than linear, suggesting a mid-range optimal level of statistics anxiety. However, students’ need for achievement proved not to mediate the relationship between anxiety and performance. The authors suggest ways these findings may influence future research in statistics anxiety and classroom management of anxiety.
First published May 2008 at Statistics Education Research Journal: Archives
A FRAMEWORK TO SUPPORT RESEARCH ON INFORMAL INFERENTIAL REASONING5
Authors: ZIEFFLER ANDREW , GARFIELD JOAN , DELMAS ROBERT , READING CHRIS
Published: April 2022

Informal inferential reasoning is a relatively recent concept in the research literature. Several research studies have defined this type of cognitive process in slightly different ways. In this paper, a working definition of informal inferential reasoning based on an analysis of the key aspects of statistical inference, and on research from educational psychology, science education, and mathematics education is presented. Based on the literature reviewed and the working definition, suggestions are made for the types of tasks that can be used to study the nature and development of informal inferential reasoning. Suggestions for future research are offered along with implications for teaching.
First published November 2008 at Statistics Education Research Journal: Archives
DEVELOPING YOUNG STUDENTS’ INFORMAL INFERENCE SKILLS IN DATA ANALYSIS
Authors: PAPARISTODEMOU EFI , MELETIOU-MAVROTHERIS MARIA
Published: April 2022

This paper focuses on developing students’ informal inference skills, reporting on how a group of third grade students formulated and evaluated data-based inferences using the dynamic statistics data-visualization environment TinkerPlotsTM (Konold & Miller, 2005), software specifically designed to meet the learning needs of students in the early grades. Children analyzed collected data using TinkerPlots as an investigation tool, and made a presentation of their findings to the whole school. Findings from the study support the view that statistics instruction can promote the development of learners’ inferential reasoning at an early age, through an informal, data-based approach. They also suggest that the use of dynamic statistics software has the potential to enhance statistics instruction by making inferential reasoning accessible to young learners.
First published November 2008 at Statistics Education Research Journal: Archives
PAST IASE CONFERENCES
Authors: PETOCZ PETER , SHORT TOM
Published: April 2022

First published November 2008 at Statistics Education Research Journal: Archives
Questionário de avaliação da vulnerabilidade em saúde da pessoa com insuficiência cardíaca: construção e validação
Authors: Cestari Virna Ribeiro Feitosa , Florêncio Raquel Sampaio , Pessoa Vera Lúcia Mendes de Paula , Moreira Thereza Maria Magalhães
Published: April 2022

Objetivo: Construir e validar um instrumento para avaliação da vulnerabilidade em saúde da pessoa com insuficiência cardíaca. Método: Estudo metodológico, constituído de uma fase de identificação dos marcadores da vulnerabilidade em saúde da pessoa com insuficiência cardíaca e outra de desenvolvimento do instrumento e validação de seu conteúdo por especialistas. Para análise da validade de conteúdo e da concordância entre especialistas, calculou-se o Índice de Validade de Conteúdo e Teste Binomial, respectivamente. Resultados: O instrumento foi composto por três dimensões, desmembradas em 110 itens, com excelentes índices de validação de conteúdo (≥0,78) e p>0,05. O índice de validação total foi de 0,99. Conclusão: Os itens permitiram a operacionalização do fenômeno de interesse e os valores obtidos na análise estatística garantiram a validade e confiabilidade do instrumento para a fase de validação externa.
Diseases caused by pathogens in the urban water system in the metropolitan region of Belém, Pará, Brazil, and their relationship with the socio-economic context of the population
Authors: De Sousa Coelho Ana Paula , Lima Tavares Yasmim Stephane , Fonseca Sousa do Nascimento Henrique
Published: April 2022

The metropolitan region of Belém-PA suffers human fecal pollution in the local water supply system favoring the increase in cases of water circulating diseases in the population, especially the most socioeconomically vulnerable. Therefore, it is necessary to compileinformation on cases of these diseases over the years in this region, in order to better define public health policies. Thus, this work aims to contribute to the gathering of this information through a literature review selecting articles found in the SciELO, Pubmed and Google Academic databases with publications between 2005 and 2021 in Portuguese and English.The neighborhoods most affected by water circulation diseases proved were Guamá, Marco, Jurunas, Tapanã, Telegrafo and Terra Firme, located close to hydrographic basins, rivers and canals and are subject to flooding due to high tides and overflowing canals. In addition, the population in these neighborhoods is considered underprivileged. The most cited diseases and symptoms were leptospirosis, worms and diarrhea, which are easily prevented. Total and thermotolerant coliforms were also widely described, being the main indicators of fecal watercontamination. The importance of sanitary measures is evidenced, as these reduce cases of water supply diseases in urban centers and improve population health. The quality of the water in the supply network is also important to mitigate the prevalence of these diseases.KEY WORDS: Pathogens; sanitation; water resources; Belém, PA.
One Parameter Discrete Ailamujia Distribution with Statistical Properties and Biodiversity and Abudance Data Applications
Authors: Ahmad Afaq , Ahmad Aijaz , Ozel Gamze
Published: April 2022

The discretization of continuous distributions among researchers become important issue, so several discretization methods exists in the literature for obtaining discrete version of continuous distribution which can be pragmatic to discrete data. The present study proposes the discretization of continuous Ailamujia distribution. Subsequently various statistical properties has been studied including moment generating function, characteristic function, mode, reliability, probability generating function etc.
Nature of density function and hazard function has been studied graphically. The technique of maximum likelihood estimation is used to estimate
the unknown parameter of the said model. Biodiversity and abundance
data applications are provided to flexibility and applicability of the new
distribution in ecological studies.
Coupled Gerdjikov-Ivanov System and its Exact Solutions through Darboux Transformation
Authors: Abbas Zaheer
Published: April 2022

The coupled Gerdjikov-Ivanov (GI) system is discussed and its elementary Darboux transformation (DT) is constructed. From elementary (DT), we constructed 2N-fold (DT). The symmetrical properties of the Lax pair and iteration of 2N-fold (DT) give different types of solutions for both zero seed and non-zero seed. Zero seed solutions include brightbright (one and two) Soliton solutions. In non-zero seed solutions, we obtained breather, Ma breather, dark-bright Soliton, breather fission, and dark-bright rogue wave solutions are obtained and plot it.
К теории параметрического усиления коротких лазерных импульсов в нелинейных фотонных кристаллах
Authors: Сабиров О.И. , Акбарова Н.А. , Сапаев У.К.
Published: April 2022

Теоретически исследован процесс параметрического усиления коротких (фемтосекундных) лазерных импульсов в кристаллах с регулярной доменной структурой. Основное внимание уделено на формирование сигнального импульса при влиянии дисперсии среды и кубической нелинейности керровского типа. Показано, что незначительное изменение размера доменов от их точного значения, определяемого когерентной длиной, может значительно увеличить эффективность сигнальной волны. Это объясняется тем, что фазовые сдвиги, вызванные влияниями нелинейности третьего порядка и дисперсии среды (как правило, они влияют только на обобщенные фазы нелинейного взаимодействия волн), могут частично компенсироваться влиянием «избыточного» волнового числа нелинейной решетки. На основе полученных результатов проанализированы оптимальные значения размера доменов, при которых наблюдается максимальная эффективность генерации сигнальной волны в условиях самовоздействия и нестационарности.
Investigation of Inhibition Effects of Some Natural Phenolic Compounds on Glutathione S-transferase (GST)
Authors: Fikret Turkan Fikret Turkan
Published: April 2022

Herein, we report the experimental results of the inhibition effects of some phenolic compounds such as 2,4,6-Trihydroxybenzaldehyde, 3,4-Dihydroxy-5-methoxybenzoic acid, Serotonin hydrochloride on α-amylase, α-glycosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and glutathione S-transferase (GST) enzymes. α-Amylase from porcine pancreas, α-glycosidase from Saccharomyces cerevisiae, glutathione s-transferase from human placenta, acetylcholinesterase from human erythrocytes and Butyrylcholinesterase from equine serum were used as enzymes. These enzymes play a very important role in metabolism. In this study the Ki values obtained by the experiments done for the compounds on some enzymes such as GST, AChE, BChE, α-amylase and α-glycosidase were found in the range of 0.31±0.5–1.02±0.3 µM, 484.03±45.45–802.83±104.3 µM, 238.22±67.31–482.73±125.6 µM and 9.28±0.56–11.23±3.43 µM, respectively. The experiment results showed that the α-amylase enzyme has a selective inhibitory effect and its IC50 values were found to be in the range of 0.92–9.63 µM. As a result, it was found that these phenolic compounds have a selective effect on α-amylase, α-glycosidase, AChE, BChE and GST enzymes, and they can be used as antiparasitic, antidiabetic and anticholinergic.
Simultaneous Determination of Etoposide and Paclitaxel in Biological and Pharmaceutical Samples by RP-HPLC; Method Development
Authors: M. Hassan M. Hassan , Zafar Iqbal Zafar Iqbal , Fazli Nasir Fazli Nasir , Ismail Khan Ismail Khan , Fahim U. Khan Fahim U. Khan , Farhad Ullah Farhad Ullah , Saifullah Khan and Nabeela Niaz Saifullah Khan and Nabeela Niaz
Published: April 2022

A simple, rapid and sensitive RP-HPLC-UV method was developed for quantification of paclitaxel (PTX) and etoposide (ETO) in biological and pharmaceutical samples. Optimization of experimental conditions were performed and standard guidelines were used for the validation of the method. Analytes were separated on Pruospher® Star RP- 18e (250mm × 4.6mm, 5µm) column using ACN and TFA (0.025%) as mobile phase in the ratio of (60:40V/V) with a flow rate of 1 mL/min and detector set at 235 nm. Protein precipitation method was applied for the extraction of analytes from biological samples. The method was applied to in-vitro and in-vivo evaluation of polymeric nanoparticles of etoposide. Solvent evaporation technique was used for the preparation of polymeric nanoparticles (NPs) using polymer PLGA (75:25) and poloxamer as surfactant. The linearity of the method is in the range of 14-500 ng / mL for paclitaxel and 12-1000 ng/mL for etoposide. The LLOD were 5 and 6 ng/mL while the LLOQ were 12 and 14 ng/mL for etoposide and paclitaxel, respectively. The developed method was precise and its intra and inter day co-efficient of variance was below 1%. The method was used for in-vitro and in-vivo evaluation of PLGA polymeric nanoparticles of etoposide. In-vitro evaluation included determination of drug content and drug release while in-vivo evaluation consisted of pharmacokinetic evaluation.
Superior Block Length and Reduced Opioid Use with Dexmedetomidine and Dexamethasone regional block versus plain Ropivacaine: a retrospective trial
Authors: Berger Amnon A , Syed Zuby , Ryan Lianne , Lee Christopher , Hasoon Jamal , Urits Ivan , Viswanath Omar , Cornett Elyse M , Kaye Alan D , Eskander Jonathan P
Published: April 2022

Purpose

The purpose of this study is to determine if using a combination of dexamethasone and dexmedetomidine (Dex-Dex) in a single-shot perineural local anesthestic provides an increased duration of pain relief and reduced consumption of opioids for patients undergoing shoulder surgery.

Patients and methods

This is a retrospective trial of adult patients without major comorbidities undergoing elective, upper arm orthopedic procedures with regional nerve block for post-operative analgesia. Patients underwent nerve block with either 0.5% ropivacaine or 0.2% ropivacaine with 5mg dexamethasone and 25mg dexmedetomidine (“dex-dex”). Patients were assessed in 1-week intervals for two weeks for duration of block analgesia, pain scores, and opioid use.

Results

31 patients were included, 12 controls and 19 in the dex-dex group. These patients underwent one of arthroscopic rotator cuff repair, reverse total shoulder repair or repair of humerus fractures. Dex-dex blocks provided significantly longer analgesia (median block time 3.5 versus 1.5 days, p<0.0001), significantly better analgesia (mean NRS 2.32 versus 8.58 on post-operative day 1, p<0.0001), and significantly reduced opioid requirements (108.16mg vs 275.63mg in MME, p<0.0001). One patient experienced transient hypotension and prolonged paresthesia in the dex-dex group.

Conclusion

Preoperative single-shot interscalene nerve blocks with preservative-free dexamethasone and dexmedetomidine added as adjuvants to ropivicaine provide approximately two additional days of benefit versus ropivicaine alone. Additionally, postoperative opioid consumption is reduced.
Schmorl’s Node: An Uncommon Case of Back Pain and Radiculopathy
Authors: Pietrok Allyson , Lee Christopher , Kaye Rachel J. , Kaye Alan D. , Chesteen George
Published: April 2022

Background

Schmorl’s nodes are herniations of nucleus pulposus through the cartilaginous and bony endplate into the adjacent vertebra. Schmorl’s nodes are extremely common and are typically seen as incidental findings on radiographic imaging. In postmortem studies, it has been estimated that greater than 70% of the population has Schmorl’s nodes. Rarely, however, Schmorl’s nodes can be a cause of acute back pain and, even less often, radiculopathy.

Case Presentation

In the present case, an elderly male presented with an acute onset of lower back pain and radiculopathy. MRI demonstrated a large L3 vertebral body inferior endplate Schmorl’s node with posterior extension through the vertebral body cortex and into the ventral epidural space superiorly. This resulted in severe effacement of the right L2-L3 subarticular recess, as well as the right L3-L4 neural foramen, impinging on the right L3 nerve root. Surrounding cortical edema and enhancement on MRI further suggested an acute Schmorl’s node.

Conclusion

Although rare, Schmorl’s nodes can be a cause of acute back pain and, even less commonly, radiculopathy. The imaging modality of choice for the diagnosis of a Schmorl’s node is MRI as it has a greater capability to detect edema, neovascularization, and in this case, extruded disc material. In both asymptomatic and symptomatic cases, the mainstay of treatment for Schmorl’s nodes is conservative therapy. Surgical removal of disc material has been successful in cases of persistent radiculopathy from compression by a tunneling Schmorl’s node.
Debridement and implant retention in acute hematogenous periprosthetic joint infection after knee arthroplasty: a systematic review.
Authors: Balato Giovanni , Ascione Tiziana , de Matteo Vincenzo , Lenzi Marco , Amato Massimiliano , de Giovanni Roberto , Festa Enrico , Mariconda Massimo
Published: April 2022

Debridement, antibiotic, and implant retention (DAIR) can be used as a first surgical procedure for acute infections in patients who have well-fixed components. However, its use in hematogenous or late acute infections is still debated. This systematic review of literature aims to clarify the effectiveness of DAIR procedure in the treatment of hematogenous periprosthetic knee infections.

DAIR is an effective way to treat acute hematogenous PJIs of the knee and reaches its best efficacy when performed within one week from the onset of symptoms, modular components are exchanged, and a pathogen-oriented antibiotic therapy can be set. It is safe, economic, and effective technique, but has to be performed in a very narrow temporal window.
Return to sport following distal femur osteotomy: a systematic review
Authors: Ciolli Gianluca , Proietti Lorenzo , Mercurio Michele , Corona Katia , Maccauro Giulio , Schiavone Panni Alfredo , Cerciello Simone
Published: April 2022

Introduction

Distal femur osteotomies (DFOs) are well-accepted procedures in treating unicompartmental knee osteoarthritis associated with valgus malalignment. This study aims to investigate the Return to sport (RTS) after DFO.

Materials and methods

We conducted a systematic review of the literature according to the PRISMA guidelines, including all articles published in English, with no time limit, excluding double-level knee osteotomies.

Results

Five articles were included for an overall cohort of 76 patients. The mean follow-up was 45.53 months. The mean age of the patients at the time of surgery was 33.87 years, and the mean malalignment was 5.59° in valgus. In 70 cases, patients received a lateral DFO, while in 6 cases, a medial closing-wedge DFO. An RTS of 86.1% was observed after DFO and a mean time to RTS of 12.3 months. 76.8% of patients recovered to a level equal to or higher than that practiced before the onset of symptoms. No statistically significant differences were observed in the RTS rate between those who performed lateral or medial DFO.

Conclusions

RTS after DFO is ubiquitous and occurs around one year after surgery. In most cases, patients report improved performance compared to what they experienced before the onset of symptoms. Unfortunately, while athletes often have RTS at a similar or better level, other patients often see a return to lower impact sports.
Tranexamic acid in total knee replacement and total hip replacement – a single-center retrospective, observational study
Authors: Konarski Wojciech , Poboży Tomasz , Hordowicz Martyna
Published: April 2022

Background

Numerous strategies are used to decrease the risk of the need for [allogeneic blood transfusion (ABT)], including [tranexamic acid (TXA)].

Objective

In a single-center retrospective observational study, we have assessed the impact of TXA on the need and average volume of blood used during transfusion.

Methods

We have reviewed medical records of a total of 491 patients undergoing arthroplasty in our hospital from Dec 2016 to Dec 2019.

Results

226 patients were administered TXA IV, and 265 did not receive an additional intervention. In the TXA group, 7/226 patients required ABT vs. 41/265 in the non-TXA group (p<0,001). The Non-TXA group required a significantly higher blood transfusion volume than the TXA group (mean 82,42 mL vs. 12,74 mL; p<0,001).

Conclusion

We conclude that two doses of 1g TXA administered [intravenously (IV)] before incision and during skin suturing reduce the need for blood transfusion in patients undergoing JRS.
Use of muscular flaps for the treatment of knee prosthetic joint infection: A systematic review
Authors: Rovere Giuseppe , Smakaj Amarildo , Calori Sara , Barbaliscia Marco , Ziranu Antonio , Pataia Elisabetta , Maccauro Giulio , De Mauro Domenico , Liuzza Francesco
Published: April 2022

Deep periprosthetic infection after total knee arthroplasty is a serious and challenging complication for the orthopedic surgeon. Muscular flaps may represent a valid treatment option for the treatment of this condition. We present a systematic literature review about the use of muscular flaps for the treatment of knee prosthetic joint infection.

The review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. 70 articles, out of 589 titles, were considered eligible for the full-text analysis. Finally, 27 studies that met inclusion criteria were included in this review. Overall, 345 patients (139 males, 206 females) suffering from TKA infection treated with muscular flaps were collected. The mean age was 57.3 years. Mean follow-up, reported in all studies, was 30.1 months.

The results presented by the different authors, highlight the effectiveness of muscular flaps for the treatment of periprosthetic infection, in terms of function, limb salvage, prevention of recurrences, cost-effectiveness, and quality of life postoperatively.

Muscle flaps provide an excellent management option for patients with persistent infection after total knee arthroplasty.
Combination Olanzapine and Samidorphan for the Management of Schizophrenia and Bipolar 1 Disorder in Adults: A Narrative Review
Authors: Haddad Hannah W. , Boardman Elena , Williams Brooke , Mouhaffel Rama , Kaye Adam M. , Kaye Alan D.
Published: April 2022

Schizophrenia is a debilitating psychotic disorder characterized by positive symptoms such as delusions, hallucinations, and disorganized thoughts, and negative symptoms like lack of effect or motivation. Bipolar 1 disorder (B1D) is a psychiatric illness characterized by recurrent manic episodes in alternation with depressive episodes and interspersed periods of euthymia, ultimately resulting in psychological distress and impairment of daily functioning. Effective treatments are needed for both schizophrenia and B1D to reach the treatment goals of reducing the debilitating symptomology, improving social functioning and quality of life, and increasing the chances of recovery and more favorable long-term outcomes. To date, olanzapine is one of the most efficacious atypical antipsychotics (AAPs) for the treatment of both schizophrenia and B1D and is associated with fewer extrapyramidal effects compared to other treatments. However, compared to other AAPs, olanzapine is associated with a greater chance of metabolic syndrome, limiting its clinical use and affecting treatment compliance. Samidorphan mitigates the weight gain side effects of olanzapine by antagonizing μ-, κ-, and δ-opioid receptors. The use of combination drugs to treat psychiatric conditions is an emerging field with the goal of increasing therapeutic efficacy and decreasing undesirable side effects. Clinical trials have demonstrated combination on olanzapine and samidorphan (OLZ/SAM) treatment resulted in significantly less weight gain than olanzapine monotherapy. Clinical trial patients reported improvements in symptoms of psychosis, reduced weight gain, and overall satisfaction with their treatment. OLZ/SAM has been as shown to be a safe and effective pharmaceutical option for the clinical management of schizophrenia and B1D.
Processus Achat 5.0 et Acheteurs Augmentés : L’IA collective avec chat-bots dotés d’aversion au risque post-COVID-19
Authors: CHEHBI GAMOURA Samia
Published: April 2022

A l’aube de la 5ème génération de la transformation digitale industrielle, le processus « Achat 5.0 » connait, lui aussi, une mutation profonde en passant d’abord par ses acheteurs, appelés « acheteurs augmentés ». Face aux défis de l’automatisation induite par cette transformation, les travaux s’accentuent et tentent de converger vers des techniques plus avancées de l’Intelligence Artificielle (IA) pour faire face au problème complexe de la sélection multifournisseurs. Les risques liés à la volatilité des fournisseurs, encore fragilisés par la crise pandémique COVID-19, ont fortement augmenté en conséquence. L’objectif de cet article est de palier à cette faiblesse. Il propose une nouvelle approche par hybridation d’analyse multicritères et des chat-bots dotés de capacité d’aversion au risque à l’aide de l’apprentissage par renforcement. Un cadre de validation d’un constructeur automobile Français nous sert de scénario préliminaire. Les premiers résultats sont prometteurs et nous encouragent à continuer dans la suite de ces travaux.
Réflexions sur les usages de la blockchain pour la logistique et le Supply Chain Management : une approche prospective
Authors: Lesueur-Cazé Mathieu , Bironneau Laurent , Lux Gulliver , Morvan Thierry
Published: April 2022

Dans un environnement se caractérisant par des mutations numériques profondes, objets connectées, big data, plateformes, etc., la blockchain laisse entrevoir un potentiel de changements dans le pilotage des chaines logistiques. Se pose donc la question des potentialités d’une telle technologie innovante sur la logistique et plus globalement le Supply Chain Management (SCM) et ses principes de pilotage des flux et des processus. Cet article se propose donc de faire un point prospectif sur les usages de cette technologie pour la logistique et le SCM en mobilisant le modèle du SCM proposé par Mentzer et al. (2001). Plus précisément, ce modèle nous a offert la possibilité d’étudier les conséquences de la blockchain sur les six axes définis par Mentzer et al. (2001) : les flux « produits », les flux « services », la gestion de l’information, la gestion des ressources financières, la gestion des stocks et la coordination intra et inter-entreprises. Nos résultats mettent en avant (i) la nécessaire interopérabilité des blockchains en vue d’une traçabilité complète, (ii) les questions de pouvoir qu’impliquent l’interconnexion des flux de service et (iii) la modification des frontières de l’entreprise dans une vision plus large d’entreprise étendue.
John G. C. Brainard, Early American Poet
Authors: RAABE WESLEY
Published: April 2022

John G. C. Brainard was an early nineteenth-century Hartford poet who published his works in the Connecticut Mirror between 1822 and 1827. His name and his verse have been almost lost to literary history, but he deserves reconsideration for his practice of occasional verse, notably his New Year’s carriers’ addresses. Successor to the Hartford Wits, a contemporary of Lydia Sigourney, his works were collected in Occasional Pieces (1825), in leading antebellum poetry anthologies, in Literary Remains (1832), and in Poems (1842). John Greenleaf Whittier edited his Literary Remains, a grievously faulty edition that has shaped Brainard’s critical reputation. Samuel G. Goodrich, who was close to him in Hartford, championed Brainard, recalling him fondly and promoting his place in American poetry, and Edgar Allan Poe reviewed his Poems. Two of Brainard’s carriers’ addresses, on the Connecticut River and on the topic of charity, are discussed, the latter analyzed. His poem in Uncle Tom’s Cabin, on African Colonization, is read in context with his connections to Harriet Beecher Stowe, and Walt Whitman’s marginal annotation of his Occasional Pieces are assessed for how Brainard may be read. An appendix recovers his complete published poetry, ordered by its date of appearance.
Elizabeth Palmer Peabody’s Contributions to the Boston Observer, Christian Register, and Western Messenger, 1835
Authors: GALLAGHER MARK
Published: April 2022

Previously unattributed items by Elizabeth Palmer Peabody appear in the Boston Observer, Christian Register, and Western Messenger in 1835. One side of Peabody revealed in these articles is of the experimental educator who not only was embroiled in the drama over Bronson Alcott’s teaching at the Temple School but apparently had stirred up a small controversy of her own the year prior to the publication of Conversations with Children on the Gospels (1836–37). There might be nothing quite remarkable about these transcripts except for the fact that, in one of her dialogues with her students, Peabody tells a graphically violent story about infanticide among Cuba’s enslaved population, comments that she later attempts to defend. Another side of Peabody that these writings reveal is the portrait of a young religious author inspired to write her own devotional literature. This takes the form of an early correspondence with William Ellery Channing. And there is even another side to Peabody represented in these writings. It is that of a moral instructor imparting her wisdom on the formation of moral character. Taken together, these publications are a significant addition to our knowledge of Peabody at a critical time in the transcendentalist period of her life.
Anthony Burgess, Obscenity, and America
Authors: THURLEY CHRISTOPHER W.
Published: April 2022

Fifty years ago, in December 1971, Stanley Kubrick’s A Clockwork Orange premiered in America, releasing nationwide in January 1972, causing the British author of the novel, Anthony Burgess, to be routinely called upon to discuss the topic of violence and obscenity in society. What many observers continue to overlook is that Burgess had been writing and speaking about these topics for close to a decade before the release of the film and its effects on popular culture. Using newly discovered archival and historical materials concerning his time in the United States, and being informed by Burgess’s entire canon, this essay details the untold story of Anthony Burgess’s long and particularly American association with and commentary on the topic of pornography as it related to contemporary cultural debates about obscenity, censorship, and literary and nonliterary intentions in the 1960s, 1970s, and 1980s. The findings of such research and analysis, it is argued, are crucial not only for understanding Burgess’s aesthetics and the evolution of discourse surrounding pornography in the second half of the twentieth century but also for better understanding and contextualizing American culture at the time.