Ventricular catheter development: past, present, and future

Cerebrospinal fluid diversion via ventricular shunting is the prevailing contemporary treatment for hydrocephalus. The CSF shunt appeared in its current form in the 1950s, and modern CSF shunts are the result of 6 decades of significant progress in neurosurgery and biomedical engineering. However, despite revolutionary advances in material science, computational design optimization, manufacturing, and sensors, the ventricular catheter (VC) component of CSF shunts today remains largely unchanged in its functionality and capabilities from its original design, even though VC obstruction remains a primary cause of shunt failure. The objective of this paper is to investigate the history of VCs, including successful and failed alterations in mechanical design and material composition, to better understand the challenges that hinder development of a more effective design.

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Vaginal extrusion of a ventriculo-peritoneal shunt catheter in an adult

Journal of Neurosciences in Rural Practice ◽

10.4103/0976-3147.143212 ◽

2015 ◽

Vol 6 (01) ◽

pp. 097-099 ◽

Cited By ~ 5

Author(s):

Christopher M. Bonfield ◽

Gregory M. Weiner ◽

Megan S. Bradley ◽

Johnathan A. Engh

Keyword(s):

External Ventricular Drain ◽

Pseudotumor Cerebri ◽

Ventricular Catheter ◽

Peritoneal Catheter ◽

Vaginal Cuff ◽

Cerebrospinal Fluid Diversion ◽

First Case ◽

History Of ◽

Ray Series ◽

Tomography Scan

ABSTRACTVentriculo-peritoneal shunts (VPS) are commonly used in the treatment of various neurosurgical conditions, including hydrocephalus and pseudotumor cerebri. We report only the second case of vaginal extrusion of a VPS catheter in an adult, and the first case with a modern VPS silastic peritoneal catheter. A 45-year-old female with a history of VPS for pseudotumor cerebri, Behcet’s syndrome, and hysterectomy presented to our institution with the chief complaint of tubing protruding from her vagina after urination. On gynecologic examination, the patient was found to have approximately 15 cm of VPS catheter protruding from her vaginal apex. A computed tomography scan of the abdomen and shunt X-ray series demonstrated no breaks in the tubing, but also confirmed the finding of the VPS catheter extruding through the vaginal cuff into the vagina. The patient had the VPS removed and an external ventricular drain was placed for temporary cerebrospinal fluid diversion. Ventricular catheter cultures were positive for diphtheroids. After an appropriate course of antibiotics, a contralateral ventriculo-pleural shunt was placed one week later. Although vary rare, vaginal extrusion can occur in adults, even with modern VPS catheters.

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The Art of Chinese Philosophy

10.23943/princeton/9780691200798.001.0001 ◽

2020 ◽

Author(s):

Paul Goldin

Keyword(s):

Chinese Philosophy ◽

Philosophical Tradition ◽

Current Form ◽

Han Feizi ◽

Textual History ◽

Classical Chinese ◽

History Of ◽

Crucial Characteristic ◽

The Way

This book provides an unmatched introduction to eight of the most important works of classical Chinese philosophy—the Analects of Confucius, Mozi, Mencius, Laozi, Zhuangzi, Sunzi, Xunzi, and Han Feizi. The book places these works in rich context that explains the origin and meaning of their compelling ideas. Because none of these classics was written in its current form by the author to whom it is attributed, the book begins by asking, “What are we reading?” and showing that understanding the textual history of the works enriches our appreciation of them. A chapter is devoted to each of the eight works, and the chapters are organized into three sections: “Philosophy of Heaven,” which looks at how the Analects, Mozi, and Mencius discuss, often skeptically, Heaven (tian) as a source of philosophical values; “Philosophy of the Way,” which addresses how Laozi, Zhuangzi, and Sunzi introduce the new concept of the Way (dao) to transcend the older paradigms; and “Two Titans at the End of an Age,” which examines how Xunzi and Han Feizi adapt the best ideas of the earlier thinkers for a coming imperial age. In addition, the book presents explanations of the protean and frequently misunderstood concept of qi—and of a crucial characteristic of Chinese philosophy, nondeductive reasoning. The result is an invaluable account of an endlessly fascinating and influential philosophical tradition.

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Conservation analysis of SARS-CoV-2 spike suggests complicated viral adaptation history from bat to human

Evolution Medicine and Public Health ◽

10.1093/emph/eoaa041 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 290-303

Author(s):

Kuan Cheok Lei ◽

Xiaohua Douglas Zhang

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Mutation Analysis ◽

Evolutionary History ◽

Sequence Similarity ◽

Similarity Analysis ◽

Current Form ◽

Conservation Analysis ◽

Spike Sequences ◽

History Of ◽

Spike Sequence

Abstract Background The current coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome (SARS)-CoV-2, has become the most devastating public health emergency in the 21st century and one of the most influential plagues in history. Studies on the origin of SARS-CoV-2 have generally agreed that the virus probably comes from bat, closely related to a bat CoV named BCoV-RaTG13 taken from horseshoe bat (Rhinolophus affinis), with Malayan pangolin (Manis javanica) being a plausible intermediate host. However, due to the relatively low number of SARS-CoV-2-related strains available in public domain, the evolutionary history remains unclear. Methodology Nine hundred ninety-five coronavirus sequences from NCBI Genbank and GISAID were obtained and multiple sequence alignment was carried out to categorize SARS-CoV-2 related groups. Spike sequences were analyzed using similarity analysis and conservation analyses. Mutation analysis was used to identify variations within receptor-binding domain (RBD) in spike for SARS-CoV-2-related strains. Results We identified a family of SARS-CoV-2-related strains, including the closest relatives, bat CoV RaTG13 and pangolin CoV strains. Sequence similarity analysis and conservation analysis on spike sequence identified that N-terminal domain, RBD and S2 subunit display different degrees of conservation with several coronavirus strains. Mutation analysis on contact sites in SARS-CoV-2 RBD reveals that human-susceptibility probably emerges in pangolin. Conclusion and implication We conclude that the spike sequence of SARS-CoV-2 is the result of multiple recombination events during its transmission from bat to human, and we propose a framework of evolutionary history that resolve the relationship of BCoV-RaTG13 and pangolin coronaviruses with SARS-CoV-2. Lay Summary This study analyses whole-genome and spike sequences of coronavirus from NCBI using phylogenetic and conservation analyses to reconstruct the evolutionary history of severe acute respiratory syndrome (SARS)-CoV-2 and proposes an evolutionary history of spike in the progenitors of SARS-CoV-2 from bat to human through mammal hosts before they recombine into the current form.

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Giant syringobulbia associated with cerebellopontine angle arachnoid cyst and hydrocephalus

Journal of Neurosurgery Pediatrics ◽

10.3171/2011.4.peds10565 ◽

2011 ◽

Vol 8 (1) ◽

pp. 30-34 ◽

Cited By ~ 2

Author(s):

Ai Muroi ◽

Nigel Peter Syms ◽

Shizuo Oi

Keyword(s):

Arachnoid Cyst ◽

Head Circumference ◽

Lateral Ventricle ◽

Cerebellopontine Angle ◽

External Ventricular Drainage ◽

Magnetic Resonance Images ◽

Ventricular Catheter ◽

Cerebrospinal Fluid Diversion ◽

Left Lateral Ventricle ◽

The Brain

The aim in reporting this case was to discuss the pathophysiology and treatment issues in an infant with a giant syringobulbia associated with a right cerebellopontine angle (CPA) arachnoid cyst causing noncommunicating hydrocephalus. This 7-month-old infant presented to the hospital with a history of delayed milestones and an abnormal increase in head circumference. Magnetic resonance images and CT scans of the brain showed a large CSF cavity involving the entire brainstem and a right CPA arachnoid cyst causing obstruction of the fourth ventricle and dilation of the lateral and third ventricles. Cerebrospinal fluid diversion was performed by direct communication from the syringobulbia cavity to the left lateral ventricle and from the left lateral ventricle through another ventricular catheter; external ventricular drainage was performed temporarily for 5 days. Communication between the syrinx and arachnoid cyst was confirmed. Clinically, there was a reduction in head circumference, and serial MR imaging of the brain showed a decrease in the size of the syrinx cavity and the ventricle along with opening of the normal CSF pathways. The postoperative course was uneventful, and no further intervention was necessary. On follow-up of the child at 3 years, his developmental milestones were normal. Surgical intervention for this condition is mandatory. The appropriate type of surgery should be performed on the basis of the pathophysiology of the developing syringobulbia.

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Role of the periodic table in discovery of new elements

Proceedings in Radiochemistry ◽

10.1524/rcpr.2011.0000 ◽

2011 ◽

Vol 1 (1) ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

D.C. Hoffman

Keyword(s):

Periodic Table ◽

Predictive Power ◽

Chemical Elements ◽

Chemical Properties ◽

Negative Effects ◽

Current Form ◽

Future Role ◽

History Of ◽

Chemical Techniques

AbstractThis year (2009) marks the 140th Anniversary of Mendeleev's original 1869 periodic table of the elements based on atomic weights. It also marks the 175th anniversary of his birth in Tolbosk, Siberia. The history of the development of periodic tables of the chemical elements is briefly reviewed beginning with the presentation by Dmitri Mendeleev and his associate Nikolai Menshutkin of their original 1869 table based on atomic weights. The value, as well as the sometimes negative effects, of periodic tables in guiding the discovery of new elements based on their predicted chemical properties is assessed. It is noteworthy that the element with Z=101 (mendelevium) was identified in 1955 using chemical techniques. The discoverers proposed the name mendelevium to honor the predictive power of the Mendeleev Periodic Table. Mendelevium still remains the heaviest element to have been identified first by chemical rather than nuclear or physical techniques. The question concerning whether there will be a future role for the current form of the periodic table in predicting chemical properties and aid in the identification of elements beyond those currently known is considered.

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Twitter under Storm: Social Media Response Sensitization in the Caribbean

10.31235/osf.io/8kc46 ◽

2020 ◽

Author(s):

Danilo T Perez-Rivera ◽

Alexis Josué Martínez ◽

Adriana Pons ◽

Alejandro Rodríguez-Natal ◽

Sergio Andrés Davila-Santana

Keyword(s):

Social Media ◽

Emergency Preparedness ◽

Previous History ◽

The Bahamas ◽

Sea Levels ◽

History Of ◽

The Caribbean ◽

Rising Sea Levels ◽

Hurricane Exposure ◽

Effective Design

Climate change has led to rising sea levels and warmer sea surface temperatures. These factors contribute greatly to the intensity of hurricanes and floods they provoke. Projections estimate there will be an increase of 45% to 87% in the frequency of Category >4 hurricanes originating in the Atlantic Basin, which typically impact the Caribbean and Continental United States of America. During the 2019 Hurricane Season, there were 20 depressions, 18 storms, 6 hurricanes and 3 major hurricanes. Through this work, we explored the response on Social Media to these natural phenomena as a function of their trajectory, intensity, and previous exposure of the population to intense natural disasters. Data was collected through the Twitter API. The influences of hurricane proximity and intensity on volume of Social Media production was explored. Hurricane Dorian, with its trajectory strongly threatening the previously exposed Puerto Rico, and eventually causing widespread damage in the Abaco Islands of the Bahamas, presented the strongest case for the evaluation of the dichotomy of responses between populations with differences in previous history of exposure. The landscape of historic hurricane exposure Caribbean has radically changed in recent years. Taking advantage of Big Data to help elucidate these dynamics could be instrumental in the tailoring of emergency preparedness plans and the effective design of mental health first aid strategies.

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Computational design of symmetrical eight-bladed β-propeller proteins

IUCrJ ◽

10.1107/s205225251801480x ◽

2019 ◽

Vol 6 (1) ◽

pp. 46-55 ◽

Cited By ~ 15

Author(s):

Hiroki Noguchi ◽

Christine Addy ◽

David Simoncini ◽

Staf Wouters ◽

Bram Mylemans ◽

...

Keyword(s):

Enzymatic Activity ◽

Evolutionary History ◽

Protein Complexes ◽

Protein A ◽

Protein Structures ◽

Computational Design ◽

Computational Approach ◽

Modular Architecture ◽

Cellular Processes ◽

History Of

β-Propeller proteins form one of the largest families of protein structures, with a pseudo-symmetrical fold made up of subdomains called blades. They are not only abundant but are also involved in a wide variety of cellular processes, often by acting as a platform for the assembly of protein complexes. WD40 proteins are a subfamily of propeller proteins with no intrinsic enzymatic activity, but their stable, modular architecture and versatile surface have allowed evolution to adapt them to many vital roles. By computationally reverse-engineering the duplication, fusion and diversification events in the evolutionary history of a WD40 protein, a perfectly symmetrical homologue called Tako8 was made. If two or four blades of Tako8 are expressed as single polypeptides, they do not self-assemble to complete the eight-bladed architecture, which may be owing to the closely spaced negative charges inside the ring. A different computational approach was employed to redesign Tako8 to create Ika8, a fourfold-symmetrical protein in which neighbouring blades carry compensating charges. Ika2 and Ika4, carrying two or four blades per subunit, respectively, were found to assemble spontaneously into a complete eight-bladed ring in solution. These artificial eight-bladed rings may find applications in bionanotechnology and as models to study the folding and evolution of WD40 proteins.

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Sideways in Time

10.3828/liverpool/9781789620139.001.0001 ◽

2019 ◽

Keyword(s):

Science Fiction ◽

Contemporary Fiction ◽

Ancient Rome ◽

Pulitzer Prize ◽

Current Form ◽

Alternate History ◽

Early Twenty ◽

History Of ◽

Late Twentieth ◽

Science Fiction Studies

This book is the first collection of scholarly essays on alternate history in over a decade and features contributions from a mixture of major figures and rising stars in the field of science fiction studies. Alternate history is a genre of fiction which, although connected to the genres of utopian, dystopian and science fiction, has its own rich history and lineage. With roots in the writings of ancient Rome, alternate history matured into something close to its current form in the essays and novels of the nineteenth century. In more recent years a number of highly acclaimed novels have been published as alternate histories, by authors ranging from science fiction bestsellers to Pulitzer Prize-winning literary icons. The success and popularity of the genre is reflected in its success on television with original concepts being developed alongside adaptations of iconic texts. This important collection of essays seeks to redress an imbalance between the importance and quality of alternate history texts and the available scholarship and critical readings of texts, providing chapters by both leading scholars in the field and rising stars. The chapters in this book acknowledge the long and distinctive history of the genre whilst also revelling in its vitality, adaptability, and contemporary relevance, with many of the chapters discussing late-twentieth and early-twenty-first century contemporary fiction texts which have received little or no sustained critical analysis elsewhere in print.

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Traditional weaving cultures in a global market: The case of Zapotec weavers

International Journal of Fashion Studies ◽

10.1386/infs_00038_1 ◽

2021 ◽

Vol 8 (1) ◽

pp. 85-103

Author(s):

Mark Joseph O’Connell

Keyword(s):

Cultural Citizenship ◽

Global Market ◽

Original Design ◽

Design Elements ◽

Cultural Autonomy ◽

Object Based ◽

Cultural Mediators ◽

History Of ◽

Historical Sites ◽

Unbroken Line

Carpets woven in Mexico today use design elements found at historical sites in the vicinity of their manufacture, and local Indigenous weaving techniques function within an unbroken line of traditional familial wisdom. The weaving culture of the Zapotec Nation of Oaxaca now exists at the juncture of multivalent competing visual, economic and cultural mediators, which makes for a compelling case study to examine the impacts of globalization, as well as the preservation of creative and cultural autonomy. This article describes site visits to Zapotec weaving ateliers, and also examines the history of Zapotec weaving traditions, and contemporary community engagement within these (now globalized) processes. The methodology employed is an object-based exploration of a Zapotec weaving. Fieldwork was conducted in the winter of 2019. It included an ethnographic observation of master Zapotec weavers within their ateliers; an observation of the original design inspirations at pre-Columbian architectural sites; artefact observation at the Museo Textil de Oaxaca; as well as practice-led natural dye research. Textile weaving is a natural site for the study of political agency and ‘cultural citizenship’, as it functions within a structure that safeguards traditional knowledge, as well as collectivizes local labourers within production flows.

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Design-by-Analogy: Exploring for Analogical Inspiration With Behavior, Material, and Component-Based Structural Representation of Patent Databases

Journal of Computing and Information Science in Engineering ◽

10.1115/1.4043364 ◽

2019 ◽

Vol 19 (2) ◽

Cited By ~ 2

Author(s):

Hyeonik Song ◽

Katherine Fu

Keyword(s):

Mechanical Design ◽

Semantic Content ◽

Structural Representation ◽

History Of ◽

Design By Analogy ◽

Computational Methodology ◽

Design Solutions ◽

Analogical Retrieval ◽

Novel Design

Design-by-analogy (DbA) is an important method for innovation that has gained much attention due to its history of leading to successful and novel design solutions. The method uses a repository of existing design solutions where designers can recognize and retrieve analogical inspirations. Yet, exploring for analogical inspiration has been a laborious task for designers. This work presents a computational methodology that is driven by a topic modeling technique called non-negative matrix factorization (NMF). NMF is widely used in the text mining field for its ability to discover topics within documents based on their semantic content. In the proposed methodology, NMF is performed iteratively to build hierarchical repositories of design solutions, with which designers can explore clusters of analogical stimuli. This methodology has been applied to a repository of mechanical design-related patents, processed to contain only component-, behavior-, or material-based content to test if unique and valuable attribute-based analogical inspiration can be discovered from the different representations of patent data. The hierarchical repositories have been visualized, and a case study has been conducted to test the effectiveness of the analogical retrieval process of the proposed methodology. Overall, this paper demonstrates that the exploration-based computational methodology may provide designers an enhanced control over design repositories to retrieve analogical inspiration for DbA practice.

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