Does Transportation Mean Transplantation? Impact of New Airline Routes on Sharing of Cadaveric Kidneys

2021 ◽  
Author(s):  
Guihua Wang ◽  
Ronghuo Zheng ◽  
Tinglong Dai
Keyword(s):  
Kidney Transplantation ◽  
Survival Rate ◽  
Operations Management ◽  
Data Sets ◽  
Kidney Transplants ◽  
Long Distance ◽  
Policy Initiatives ◽  
Geographic Regions ◽  
Transplantation System ◽  
The U.S

Every year, nearly 5,000 patients die while waiting for kidney transplants, and yet an estimated 3,500 procured kidneys are discarded. Such a polarized coexistence of dire scarcity and massive wastefulness has been mainly driven by insufficient pooling of cadaveric kidneys across geographic regions. Although numerous policy initiatives are aimed at broadening organ pooling, they rarely account for a key friction—efficient airline transportation, ideally direct flights, is necessary for long-distance sharing, because of the time-sensitive nature of kidney transplantation. Conceivably, transplant centers may be reluctant to accept kidney offers from far-off locations without direct flights. In this paper, we estimate the effect of the introduction of new airline routes on broader kidney sharing. By merging the U.S. airline transportation and kidney transplantation data sets, we create a unique sample tracking (1) the evolution of airline routes connecting all the U.S. airports and (2) kidney transplants between donors and recipients connected by these airports. We estimate the introduction of a new airline route increases the number of shared kidneys by 7.3%. We also find a net increase in the total number of kidney transplants and a decrease in the organ discard rate with the introduction of new routes. Notably, the posttransplant survival rate remains largely unchanged, although average travel distance increases after the introduction of new airline routes. Our results are robust to alternative empirical specifications and have important implications for improving access to the U.S. organ transplantation system. This paper was accepted by Vishal Gaur, operations management.

Limitations on digital filtering of the DNAG magnetic data set for the conterminous U.S.

Geophysics ◽  
1993 ◽  
Vol 58 (9) ◽  
pp. 1281-1296 ◽  
Author(s):  
V. J. S. Grauch
Keyword(s):  
Spatial Frequency ◽  
North American ◽  
Digital Filtering ◽  
Magnetic Data ◽  
Data Sets ◽  
Frequency Content ◽  
Long Distance ◽  
High Quality ◽  
Data Set ◽  
The U.S

The magnetic data set compiled for the Decade of North American Geology (DNAG) project presents an important digital data base that can be used to examine the North American crust. The data represent a patchwork from many individual airborne and marine magnetic surveys. However, the portion of data for the conterminous U.S. has problems that limit the resolution and use of the data. Now that the data are available in digital form, it is important to describe the data limitations more specifically than before. The primary problem is caused by datum shifts between individual survey boundaries. In the western U.S., the DNAG data are generally shifted less than 100 nT. In the eastern U.S., the DNAG data may be shifted by as much as 300 nT and contain regionally shifted areas with wavelengths on the order of 800 to 1400 km. The worst case is the artificial low centered over Kentucky and Tennessee produced by a series of datum shifts. A second significant problem is lack of anomaly resolution that arises primarily from using survey data that is too widely spaced compared to the flight heights above magnetic sources. Unfortunately, these are the only data available for much of the U.S. Another problem is produced by the lack of common observation surface between individual pieces of the U.S. DNAG data. The height disparities introduce variations in spatial frequency content that are unrelated to the magnetization of rocks. The spectral effects of datum shifts and the variation of spatial frequency content due to height disparities were estimated for the DNAG data for the conterminous U.S. As a general guideline for digital filtering, the most reliable features in the U.S. DNAG data have wavelengths roughly between 170 and 500 km, or anomaly half‐widths between 85 and 250 km. High‐quality, large‐region magnetic data sets have become increasingly important to meet exploration and scientific objectives. The acquisition of a new national magnetic data set with higher quality at a greater range of wavelengths is clearly in order. The best approach is to refly much of the U.S. with common specifications and reduction procedures. At the very least, magnetic data sets should be remerged digitally using available or newly flown long‐distance flight‐line data to adjust survey levels. In any case, national coordination is required to produce a consistent, high‐quality national magnetic map.

scholarly journals TRASPLANTE RENAL EN ECUADOR, PUNTOS CLAVE Y SITUACIÓN ACTUAL.

2021 ◽  
Vol 31 (2) ◽  
pp. 42-48
Author(s):  
Jorge Albán Tigre ◽  
Andrea Villarreal Juris ◽  
Juan Mora Betancourt ◽  
Víctor Betancourt Nole
Keyword(s):  
Kidney Transplantation ◽  
Survival Rate ◽  
Renal Dialysis ◽  
Chronic Kidney Failure ◽  
World Health ◽  
Kidney Transplants ◽  
Pediatric Kidney Transplantation ◽  
Donor Rate ◽  
Health Organization ◽  
End Stage

IntroductionKidney transplantation in Ecuador began in 1976, it was limited until 2011, when the Organic Law of Donation and Transplantation of Organs, Tissues and Cells became valid. This is indicated in end-stage renal failure, in adult and pediatric patients; and, compared to peritoneal and renal dialysis, it is less expensive for the health system. In 2015, in Ecuador, at least 30,000 people suffered from end-stage kidney disease; 45% of them could die without treatment. The objective of this study was to determine the current situation in Ecuador regarding kidney transplantation. MethodologyA descriptive, retrospective study. INDOT statistics were reviewed from 2007 to August 2019, to determine the total number of transplants and kidney transplants, type of transplant, effective donors, rate of donors per million population (pmp), transplanted organ rate (pmp), evolution of the national waiting list, survival rate, etc. Results From 2007 to 2019, 6134 transplants were performed: 25.4% renal. Most donors were male (68.1%). The donor rate (pmp) between 2009 and 2019 was 4.2 (SD: ± 2.1). The mean rate of transplanted organs was 8.1 (SD: ± 3.6) (pmp) from 2007 to 2019. In this period 1560 kidney transplants were performed: 83.1% with cadaveric donors (88.1% adults; 11.9% pediatric) and 16.9% with living donors (72.4% adults; 27.6% pediatric). The one-year survival rate after cadaveric and living donor kidney transplantation was 0.94 and 0.97 in adults; and 0.90 and 0.97 in pediatrics, respectively. Currently there are only 5 accredited centers for kidney transplantation in adults and one for pediatric kidney transplantation .ConclusionsKidney transplantation has made significant progress in Ecuador, however, it is still below the World Health Organization (WHO) goal established for the proper management of patients with chronic kidney failure.

scholarly journals Queue Length Forecasting in Complex Manufacturing Job Shops

Forecasting ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 322-338
Author(s):  
Marvin Carl May ◽  
Alexander Albers ◽  
Marc David Fischer ◽  
Florian Mayerhofer ◽  
Louis Schäfer ◽  
...  
Keyword(s):  
Operations Management ◽  
Queue Length ◽  
Manufacturing Systems ◽  
Production Control ◽  
Data Sets ◽  
Job Shops ◽  
Static Data ◽  
Queue Lengths ◽  
Operational Excellence

Currently, manufacturing is characterized by increasing complexity both on the technical and organizational levels. Thus, more complex and intelligent production control methods are developed in order to remain competitive and achieve operational excellence. Operations management described early on the influence among target metrics, such as queuing times, queue length, and production speed. However, accurate predictions of queue lengths have long been overlooked as a means to better understanding manufacturing systems. In order to provide queue length forecasts, this paper introduced a methodology to identify queue lengths in retrospect based on transitional data, as well as a comparison of easy-to-deploy machine learning-based queue forecasting models. Forecasting, based on static data sets, as well as time series models can be shown to be successfully applied in an exemplary semiconductor case study. The main findings concluded that accurate queue length prediction, even with minimal available data, is feasible by applying a variety of techniques, which can enable further research and predictions.

A time-series analysis of the U.S. kidney transplantation and the waiting list: donor substitution effects

2010 ◽  
Vol 42 (1) ◽  
pp. 261-277 ◽  
Author(s):  
T. Randolph Beard ◽  
John D. Jackson ◽  
David Kaserman ◽  
Hyeongwoo Kim
Keyword(s):  
Time Series ◽  
Kidney Transplantation ◽  
Time Series Analysis ◽  
Waiting List ◽  
Substitution Effects ◽  
Series Analysis ◽  
The U.S

The past is prologue

2018 ◽  
Vol 17 (3) ◽  
pp. 366-385 ◽  
Author(s):  
David Cassels Johnson ◽  
Crissa Stephens ◽  
Stephanie Gugliemo Lynch
Keyword(s):  
Language Policy ◽  
Language Ideologies ◽  
Public Policies ◽  
Social Structures ◽  
New Latino Diaspora ◽  
Policy Initiatives ◽  
The Past ◽  
Historical Processes ◽  
The U.S

Abstract This article examines reactions to the changing linguistic ecology in the U.S. state of Iowa, which is experiencing a demographic phenomenon often referred to as the New Latino Diaspora (NLD) (Hamann et al., 2002). We first examine the historical processes and social structures that link current language policy initiatives within Iowa to local and national nativism. We then analyze public policies and texts to reveal how language ideologies circulate across diverse texts and contexts, forming discourses that shape the experiences of Latin@s in Iowa.

Reply to “Comment on ‘Which Earthquake Accounts Matter?’ by Susan E. Hough and Stacey S. Martin” by David J. Wald

2021 ◽  
Author(s):  
Susan E. Hough ◽  
Stacey S. Martin
Keyword(s):  
Scientific Community ◽  
Recent Article ◽  
Geological Survey ◽  
Data Sets ◽  
Macroseismic Data ◽  
Education Programs ◽  
Socioeconomic Groups ◽  
Science Projects ◽  
Community Science ◽  
The U.S

Abstract We thank David Wald (Wald, 2021; henceforth, W21) for his interest in our recent article (Hough and Martin, 2021; henceforth, HM21). Although different perspectives are vital in science, we are concerned that W21 misrepresents HM21 as an oblique criticism of the U.S. Geological Survey “Did You Feel It?” (DYFI) system, calling for HM21 to be retracted. Readers who are interested in the issues raised by HM21 and the statements made by us therein are referred to that article. In this brief reply, we respond to specific accusations made by W21 and return to the focus of HM21, calling attention to the extent to which macroseismic data sets and inferences drawn from them can be shaped by a lack of representation among individuals whose observations are available to science. HM21 never questioned the benefits of the community science DYFI project to science. HM21 noted, however, and we reiterate here, that community science also potentially benefits the community. Whether or not it matters for science, if participation in community science projects is unrepresentative across socioeconomic groups, it underscores the need for the scientific community to be proactive in its efforts to reach out to groups that have been underserved by current outreach and education programs. We appreciate this opportunity to continue the important conversation about representation.

The Ghost of Helms-Burton

2019 ◽  
pp. 205-224
Author(s):  
Jonathan C. Benjamin-Alvarado
Keyword(s):  
United States ◽  
The United States ◽  
Barack Obama ◽  
Obama Administration ◽  
Policy Initiatives ◽  
Executive Action ◽  
Normalization Process ◽  
The U.S

In spite of the significant policy initiatives undertaken by the Barack Obama administration to “normalize” U.S. relations with Cuba, serious barriers and impediments lie ahead. This chapter investigates the daunting policy challenges that face the United States and Cuba in their effort to advance their bilateral diplomatic and economic affairs, owing largely to the draconian conditionality codified in the Cuban Liberty and Democratic Solidarity (Libertad) Act of 1996 (Helms–Burton Act). Given the highly partisan and divided nature of executive and legislative branches of the U.S. government, it remains uncertain as to whether Congress will allow progress in the normalization process to move beyond the limits of executive action. The chapter identifies and details the concrete steps that must be undertaken by the Congress to dismantle Helms-Burton, and under what conditions that might occur.

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