Prior research studies comparing the quality of care provided by CAHs and non-CAHs have found that risk-adjusted mortality rates at CAHs were higher, and the hospitals’ quality of care, therefore, lower. But a new study led by investigators at the Center for Gerontology and Healthcare Research in Brown’s School of Public Health suggests that standard risk-adjustment methodologies have been unfairly penalizing CAHs.

According to the study, for Medicare beneficiaries in rural areas who were hospitalized during the period of 2007 to 2017, CAHs submitted significantly fewer hospital diagnosis codes than did non-CAHs. The primary reason for the relative under-reporting of diagnoses at CAHs has to do with differences in Medicare reimbursements — while non-CAHs are incentivized by Medicare to complete diagnosis coding, CAHs, which receive cost-based reimbursements, are not.

“When payments for episodes of care are tied to the acuity of patients, health care providers have the incentive to fully report or even overstate acuity,” said study senior author Momotazur Rahman, an associate professor of health services, policy and practice at Brown. “Since payments for non-CAHs are dependent on reported acuity while payments for CAHs are not, non-CAH patients will appear comparatively sicker than they actually are.”

Because mortality rates are adjusted per severity of illness — acuity, in Rahman’s words — the result is that CAHs appear to have higher mortality rates for patients with similar conditions, when in reality their patients may in fact be sicker than those in non-CAHs, from the standpoint of risk adjustment.

The study was published in the Journal of the American Medical Association on Tuesday, Aug. 4.

How did the researchers determine that CAHs tend to overreport diagnoses? In 2010, Medicare increased the allowable number of billing codes for hospitalizations from 10 to 25.

“We observed a large jump in reported acuity among non-CAH patients in 2010,” Rahman said, “but we saw a much smaller jump for CAH patients. We found that due to this difference in acuity reporting, when compared to non-CAHs, the risk-adjusted performance of CAHs on short-term mortality measures looks much worse than it actually is.”

The CAH program, created to prevent rural hospitals from closing, has repeatedly come under threat. Given that in many parts of the U.S., CAHs serve as sole health care providers, Rahman said that examining differences in quality of care is important for understanding the value of the CAH program and informing decisions about the allocation of funding for rural health care.

The finding that short-term mortality outcomes at rural CAHs may not differ from those of non-CAHs after accounting for different coding practices, he added, is essential knowledge for ensuring timely access to acute care for vulnerable rural communities.

Other authors include Brown doctoral student Cyrus Kosar, the study’s lead author, and Lacey Loomer, Kali Thomas, Elizabeth White and Orestis Panagiotou.

Story Source:

Materials provided by Brown University. Note: Content may be edited for style and length.

As climate change threatens cultural sites, preservationists and researchers are asking whether these iconic locations should be meticulously restored or should be allowed to adapt and “transform.”

“The traditional preservationist paradigm is the idea of static preservation — materials stay in a constant state, and we protect the values identified at the time they were designated,” said Erin Seekamp, first author of a paper that raises these questions and a professor of parks, recreation and tourism management at North Carolina State University.

“However, it’s really infeasible to manage all heritage sites and property through persistent adaptation due to the extent of projected climate impacts,” Seekamp said. “We are arguing for preservationists to shift toward transformation in some cases.”

The paper was co-authored by Eugene Jo, World Heritage Leadership Programme Coordinator at the International Centre for the Study of the Preservation and Restoration of Cultural Property (ICCROM).

Seekamp and Jo presented two ideas for how transformation could take place: adaptively in response to climate change impacts, or in advance of anticipated or projected impacts.

Seekamp and Jo argue that some cultural icons “severely impacted” by climate change-related events could remain damaged to serve as a “memory” of that event, and to help communities better understand and learn about the climate-related vulnerabilities of places.

In other cases, they argued that some landmarks at risk of climate change should be allowed to “transform” when the cost of preserving a landmark is too high. Decisions about how these important landmarks can and should change need to be guided by the values of descendants of people and cultures that those sites were originally intended to highlight and preserve, they said.

“Individuals whose heritage is at stake, and who receive benefits from those places as tourist sites, should be part of the discussions about change, and about what preserving values connected with sites should look like,” Seekamp said.

Their ideas about transformation were inspired by the concept of resilience in ecology, Seekamp said, in which a landscape can absorb change in response to a disturbance, and populations shift toward a “new state” or reorganize.

“What we’re arguing is that the heritage field adopt an ecological framework of resilience to expand the current paradigm of preservation toward transformation to allow for autonomous and anticipatory adaptation to occur,” Seekamp said.

They focused their recommendations on cultural landmarks designated as World Heritage Sites, which are landmarks or areas with important cultural, natural or scientific significance that have legal protections through the United Nations Educational, Scientific and Cultural Organization, or UNESCO.

They argued that preservation leaders create a new category for sites facing climate threats called “World Heritage Sites in Climatic Transformation.” That list could help gather information and better document sites that face threats from climate change, as well as help channel resources toward them.

“We are argue that policy reform is needed to create the flexibility that would allow for both the continuity of heritage values, and the evolution of place meaning and societal benefits in face of climate change,” Seekamp said.

Seekamp also indicated that the new designation could aid a natural landmark like Florida’s Everglades National Park. While the park isn’t a site recognized for its cultural heritage, which was the focus of Seekamp’s viewpoint — it was designated as a World Heritage Site because of its outstanding geologic and natural features — there are material remains of heritage present that are also at risk to rising seas and increasing temperatures.

The park is the traditional lands of the Seminole Tribe of Florida and the Miccosukee Tribe, as well as the Calusa. The designation of the park as a “World Heritage Site in Climatic Transformation” could allow managers to think about alternatives that better integrate culture and cultural values in changing environments, Seekamp said.

“We’re not saying that this should open the door for development or tourism,” Seekamp added. “We’re saying, ‘Let’s create a new categorization, and enable those places to not just think about persistent adaptation, but about transformative adaptation.’ It allows us to think about alternatives.”

This discovery was published in Nature Materials.

The breakthrough focused on reducing barriers for molecules accessing the interior pores of catalysts, called zeolites — aluminosilicates with pores smaller than a nanometer. Zeolites are widely used in commercial processes as solid catalysts for the production of gasoline and value-added chemicals and other products.

In these applications, chemistry within the zeolite pores first requires molecules to find the small number of openings on the outside surface of catalyst particles. This creates a queue of molecules that must “wait in line” to enter the particle, diffuse to the active site involved in the chemical reaction, and then exit the particle.

One approach to address these transport problems has been to synthesize small nanoparticles. As zeolites become smaller, the amount of surface area exposing the pores increases per amount of catalyst material, which grants increased access for molecules entering the pores. Smaller particles also reduce the internal distance molecules must travel through the particle.

However, the synthesis of these smaller zeolite particles is expensive, and the resulting particles are often too inefficient for practical applications.

Researchers at the University of Houston, led by Jeffrey Rimer, Abraham E. Dukler Professor of chemical and biomolecular engineering, developed a way to induce larger catalyst particles to behave like nanoparticles — that is, to allow molecules to enter, spark a reaction and exit quickly, by growing protrusions, or fins, on the surfaces of catalyst particles. By adding nanoscale fins that protrude from the external surface of large particles, the roughened exterior of the particle significantly increased in surface area, granting molecules increased access and reducing the transport limitations that frequently plague conventional zeolite materials.

“Our new synthesis approach capitalizes on work we have been doing in our group for many years, focused on controlling zeolite crystallization in ways that enable the growth of fins,” Rimer said. “This new class of materials bypasses the need to directly synthesize nanoparticles, creating a new paradigm in zeolite catalyst design.”

Rimer worked with a team of international experts in materials synthesis, characterization and modeling to demonstrate the capability of finned zeolites to improve the performance of this unique family of solid catalysts. By comparing finned zeolites with conventional catalytic materials, they showed that zeolites with fins lasted almost eight times longer. Rimer said the incorporation of fins leads to shorter internal diffusion pathways and ensures molecules efficiently reach the reaction sites while reducing the propensity of carbon-based species to become immobilized. That build up ultimately deactivates the catalyst.

Xiaodong Zou, professor of inorganic and structural chemistry at Stockholm University, and members of her laboratory conducted advanced 3D electron microscopy characterization to unravel the pore structures of the finned crystals and confirmed that the fins were extensions of the underlying crystal and did not create impediments for internal diffusion.

“It is amazing to see how well all these hundreds of individual nanofins are aligned with the parent crystal,” Zou said.

Additional state-of-the-art techniques for characterizing zeolite catalysts in real time were performed at Utrecht University by the research group of Bert Weckhuysen, professor of catalysis, energy and sustainability. These measurements confirmed the exceptional ability of finned zeolites to prolong catalyst activity well beyond that of larger catalysts.

Weckhuysen said the use of operando spectroscopy clearly showed how the introduction of fins lowered the amount of external coke deposits during catalysis. “That substantially increased the lifetime of finned zeolite crystals,” he said.

Jeremy Palmer, assistant professor of chemical and biomolecular engineering at UH, used computational methods to model finned materials and explain how the new design works to improve catalysis.

Researchers had expected the fins would perform better than a standard-sized zeolite catalyst, he said. “But we found it was not just a 10% or 20% improvement. It was a tripling of efficiency. The magnitude of the improvement was a real surprise to us.”

Additional work at the University of Minnesota by the research group of Paul Dauenhauer, professor of chemical engineering and materials science, and by Michael Tsapatsis, professor of chemical and biomolecular engineering at Johns Hopkins University, confirmed the enhanced mass transport properties of finned zeolites. Using a new method to track molecule diffusion by infrared light, the UM researchers demonstrated that the fins enhanced molecule transport between 100 and 1,000 times faster than conventional particles.

“The addition of fins allows molecules to get inside the channels of zeolites where the chemistry happens, but it also lets molecules quickly get out of the particle, which lets them operate for a much longer period of time,” Dauenhauer said.

The discovery has immediate relevance to industry for a host of applications, including the production of fuels, chemicals for plastics and polymers, and reactions that make molecules for food, medicine and personal care products.

“The beauty of this new discovery is its potential generalization to a wide range of zeolite materials, using techniques that are easy to incorporate in existing synthesis processes,” Rimer said. “The ability to control the properties of fins could allow for much greater flexibility in the rational design of zeolite catalysts.”

This work was supported by and is part of a larger mission of the U.S. Department of Energy, with additional support provided by various international funding agencies.