bluuebunny/crossref_metadata_2025 huggingface dataset:
DISPERSANT EFFECTIVENESS ON OIL SPILLS – EMPIRICAL CORRELATIONS
Authors: Nagarajan Kavitha R. , Deshpande Niranjan , Sorial George A. , Weaver James W.
Published: January 2013

When a dispersant is applied to an oil slick, its effectiveness in dispersing the spilled oil depends on various factors such as oil properties, wave mixing energy, temperature of both oil and water, and salinity of the water. Estuaries represent water with varying salinities. In this study three salinity values in the range of 10–34 ppt were investigated, representing potential salinities found in typical estuaries. Three oils were chosen to represent light refined oil, light crude oil and medium crude oil. Each oil was tested at three weathering levels to represent maximum, medium and zero weathering. Two dispersants were chosen for evaluation. A modified trypsinizing flask termed the ‘Baffled Flask’ was used for conducting the experimental runs. A full factorial experiment was conducted for each oil to investigate the effect of salinity (3 levels), temperature (6 levels), oil weathering (3 levels) and mixing energy (150, 200, and 250 rpm) on dispersant effectiveness. Each experiment was replicated four times in order to evaluate the accuracy of the test. Statistical analyses of the experimental data were performed separately for each of the three oils three times (with or without dispersant). Viscosity of the three oils at the different temperatures and weathering conditions were determined. An empirical correlation of the viscosity for each of the three oils was then obtained. A linear regression model incorporating the viscosity correlations to represent temperature and weathering, the other remaining main factors (salinity and flask speed) and second order interactions among the factors was developed and was found to accurately represent the experimental data. The empirical approach to the interaction between the dispersant and oil slick developed could provide a useful or practical approach for including dispersants in a model to assess the impact of dispersant usage on oil spills.
MAXIMIZING DISPERSANT PREPAREDNESS: LESSONS LEARNED FROM THE 2007 HAWAIIAN ISLANDS FULL SCALE EXERCISE
Authors: Beasley Kim , Martin C. Curtis , Laferriere Roger
Published: January 2013

Large scale dispersant exercises have been conducted nationally and internationally ever since their first large scale use during the Torrey Canyon Spill of 1967. Few of these exercises are conducted on the grandest scale intended to exercise all aspects of the operation; from command and control, pre-application testing, application, monitoring and data transmission. Clean Islands Council in cooperation with the State of Hawaii'S Department of Health and the U.S. Coast Guard conducted a two day exercise on February 21–22, 2007 to test the full range of the State'S Dispersant capability. It was the largest exercise ever conducted in Hawaii, and arguably the largest in United States history. The exercise was the culmination of 14 years of program development by the Clean Islands Council, the State of Hawaii and the United States Coast Guard. The exercise instilled a tremendous appreciation in all players involved of the complexity of dispersant operations, and the importance of ensuring efficient command and control processes, support and communications. All elements of Dispersant application were tested: decision making processes, laboratory pre-testing, on-scene test application, on-scene application, on-scene monitoring and real time data transmission to effect quick decision making from jurisdictional agencies. Additionally, the latest state of the art equipment was used during all phases. This paper discusses the results of the exercise and shares critical lessons learned that will greatly advance the preparedness knowledge of all dispersant users internationally. The authors of this paper have over 50 years of collective spill response experience and were personally involved in the exercise design and execution.
HIGHLAND BAYOU: APPROVED DESTRUCTION OF A MARSH
Authors: Baccigalopi Michael J. , Kartye J. Craig
Published: January 2013

On December 18, 2004 the Texas General Land Office Oil Spill Prevention and Response Program was notified of a spill originating from an abandoned tank battery located in the marsh of Highland Bayou near Galveston, Texas. The discharge of 9460 gallons of crude oil into the bayou and adjacent marsh resulted from lack of maintenance to the tank battery. A vertical pipe attached to one of the tanks rusted through, allowing the tank to drain. The oil did not flow over the secondary containment, but seeped underneath it and spread through the marsh. This flow-path complicated the response by concentrating the spill in the subsurface, thereby impacting the roots system of the marsh plants, and rendering response techniques such as underflow dams, low water flushing, and in-situ burning either minimally effective or not viable. Aggressive tactics such as trenching and digging of holes in combination with massive water flushing were used to remove the oil. Short and long term consequences from these aggressive tactics were clearly evident in the trampling of the marsh grasses and changing of the local hydrology during clean-up operations. Initial trustee assessments determined the heaviest area impacted had died and was to be tilled. This provided a valuable learning opportunity for area responders and saved the surrounding acres of marsh.
ANALYSIS OF OIL SPILL RESPONSE PERFORMANCE USING MODELS
Authors: Konkel Wolfgang J. , McCay Deborah French
Published: January 2013

The utilization of oil spill models is typically associated with the development of oil spill contingency plans, the support of spill response exercises, or the simulation of trajectories and weathering in actual spill incidents. Some spill models have the capability to simulate spill response through the removal of surface oil by mechanical recovery, in-situ burning, or by the application of dispersants. These models require that the basic operating parameters of the response equipment are entered into the models. The models remove oil from the surface using those parameters within the environmental operating limits for that technology. This type of analysis can be valuable in evaluating the success of spill responses under various conditions.

The simulation of oil spill response equipment in the SIMAP Model has been enhanced with the incorporation of a Spill Tools Calculator. The calculator readily incorporates various types of spill response equipment and associated operational parameters. Spill equipment is then applied to responses on a day-by-day basis using realistic travel times, storage capacities, and slick-intercept capabilities. This analysis allows for a realistic, albeit, optimistic prediction of spill response performance. A thorough understanding of the potential performance of a response early in a spill allows regulators and resource managers the opportunity to make decisions that may improve the ultimate success of the response.

The SIMAP Model provides numerous estimates of spill effects, e.g. shoreline oiling area and mass, and water concentrations of aromatics and total hydrocarbons. These parameters, in conjunction with the mass balance and response performance indicators, are valuable in comparing the results from various spill response alternatives. This information provides regulators and resource managers an understanding of the implications of various response alternatives and enables the selection of response alternatives that best meet the priorities in the area.
AUTOMATED SHORELINE OILING DATA GENERATION FOR SPILL DRILLS AND SCENARIOS
Authors: Reimer P.D. , Lamarche A. , Owens E.H.
Published: January 2013

Realism during drills and exercises is sometimes difficult to achieve. A new technique to quickly and easily create data on “oiled shorelines” also generates displays that can be viewed on Google Earth™. Shoreline surveys are a fundamental aspect of any spill response and the data generated by these field surveys forms the basis for decisions by the spill management team regarding operational strategies, treatment tactics, and treatment end points. During an actual spill event these data are collected by field teams that survey the affected area and generate reports that are entered into a data management system. Oil spill drills and scenario exercises are a practical method to evaluate response functionality, train personnel and maintain readiness for both private sector organizations and regulatory agencies. Teams can be assembled, oil trajectories simulated, and all of the response decisions practiced. The one factor typically that is missing is actual oiled shoreline data to drive the decision process. Generation of this shoreline oiling data can be time consuming and require a level of effort that may not be considered warranted in terms of time and cost. A simple and rapid technique has been developed to create detailed and realistic oiling conditions on shorelines to address this deficiency. The data that is generated includes length, width, distribution, and thickness of oil within a selected tidal zone or zones; all of the typical SCAT data. This data can be easily transferred to GIS and database systems to generate the reports required by the management team and to track simulated cleanup activities. A similar application is to generate data for scenarios that commonly are included in oil spill response or contingency plans. This technique was used successfully during a major spill drill in Prince William Sound Alaska in May, 2007.
SUNKEN OIL AND THE REMOVAL OF OIL FROM SUNKEN WRECKS
Authors: Parker Hugh , Moller Tosh
Published: January 2013

Following the technical triumph of removing most of the oil from the sunken wreck of the PRESTIGE, interest and expectations have been raised in equal measure. Since 2005 there have been a number of incidents worldwide involving sunken wrecks containing oil, as well as a smaller number of pollution cases in which oil spilled from ships has sunk due to its high specific gravity. The response to such incidents poses unique challenges and reference is made to ITOPF'S database of historical spills in order to demonstrate how attitudes and the policies for dealing with these cases have changed.

The problems posed by oil in wrecks or on the seabed straddle the disciplines of ship salvage and conventional spill clean-up. Whilst the technology used in recovering such oil differs, the rationale for determining whether or not certain measures have merit is in large part based on an assessment of what is technically reasonable. These principles are reflected in the development of the IOPC Funds’ technical guidelines for the removal of oil from sunken wrecks. This paper explores the evolution of response policy with reference to key shipping incidents involving sunken wrecks and sunken oil. In the course of this review, the conflicts between public expectations and technical limitations are highlighted.
THE MOVEMENT OF OIL AT SEA DUE TO IRREGULAR WAVES
Authors: Bechtel Ryan D. , Wickley-Olsen Erik , Boufadel* Michel C. , Weaver James , Barker Christopher
Published: January 2013

Our previous work investigated the transport of oil under regular waves at sea. This work considered irregular waves represented by a JONSWAP spectrum, which is a more realistic situation. Particle tracking was used in a Monte Carlo framework to evaluate the combined effects of wave kinematics and turbulent diffusion on the transport of oil droplets at sea. The centroids, variance and spreading coefficients of oil spills with various wave parameters were found in this study. Turbulent diffusion was assumed to be velocity-dependent, and an empirical formulation adopted from subsurface hydrology was adopted. Five hundred neutrally-buoyant oil “particles” were placed at the water surface and tracked for 1 hour. The vertical movement of the plume appeared to be comparable to the significant wave height (about one meter herein), and to decrease with depth. The increase in wind fetch caused an increase in transport and spreading of the plume. The results found in this study can be used by spill responders as a first approximation to the spread of a dispersed oil spill, or can be used as parameters as part of a more complex code used to model oil spills.
ASPHALT BARGE MM53 AND THE OHIO RIVER
Authors: Howard GREGORY A. , Laisure Donald L.
Published: January 2013

On January 26th, 2006, while southbound on the Ohio River, a towboat with three barges attempted to enter Louisville, Kentucky'S McAlpine lockway during high water levels. The barge tow allided with the starboard approach fender resulting in the loss of the entire tow. While two barges were recovered without loss of product, the third struck the K&I railroad bridge and eventually flipped onto its port side, discharging 220,000 (832.8 m3) gallons of oil into the river.

This paper will examine the challenges associated with the release of asphalt in a major navigable river, removal of solid asphalt from a stricken 300-foot (91.4 m) long barge and the ultimate salvage of the barge beneath a working railroad bridge. This paper will discuss operational decisions from the perspective of pollution response, salvage, safety, and command experiences coordinating efforts of the federal government and two states, a protracted event in urban setting and environmental pressures.
BIRD INJURY AND RESTORATION SCALING: AN ECOLOGICAL FRAMEWORK
Authors: Wakefield Jeffrey R. , McNutt Juli Anna
Published: January 2013

Habitat Equivalency Analysis (HEA) and Resource Equivalency Analysis (REA) each require the Natural Resource Damage Assessment (NRDA) practitioner to assess both the likely behavior of impacted systems or populations had there not been a pollution event (baseline) and the response of the impacted system/populations given the pollution event, response actions, and restoration. In the past several years, a general consensus regarding the approach and biological assumptions underlying HEA has arisen. While the details vary with the particulars of the spill, cooperative NRDA for Chalk Point, M/V Stuyvesant, Lake Barre, and other spills reveal an emerging consensus surrounding the application of HEA to specific components of oil spill assessment.

The same progression and consensus has not been observed with respect to the biological assumptions underlying REA. Assessments conducted for the Chalk Point (NOAA et al. 2002a), the Lake Barre (Penn and Tomasi 2002), North Cape (Sperduto et al. 1999, 2003) the Stuyvesant (CDFG et al. 2004), the Anitra (NJDEP et al. 2004) and the New Carissa (MIV New Carissa 2006) oil spills have used REA frameworks that differ from one another. Further, the variation in REA frameworks alone has resulted in NRD assessments that would differ by millions of dollars, even if all assumptions related to initial injury levels, underlying biological parameters, and the functioning of restoration projects were identical.

The purpose of this paper is to fuse the work of Penn and Tomasi (2002) Sperduto et al. (1999, 2003), NOAA et al. (2002a), CDFG et al. (2004) Zafonti and Hampton (2005) and others with basic ecological theory to refine and extend current practices resulting in a more standardized approach to REA.

For spills in which chronic, long term exposure is not an issue, we apply basic ecological approaches that consider a species ability to respond to environmental perturbation based on (1) changes to the proportion of adults attempting to breed, (2) changes in productivity (defined as fledglings per nesting pair), and (3) changes to annual survival rates. We show that, these factors, when integrated with a simple set of population dynamic equations, provide NRDA practitioners a common, easily understood framework upon which they can assess damages and the necessary scale of potential restoration options.
NOAA OFFICE OF RESPONSE AND RESTORATION'S ROLE DURING OIL SPILLS WHERE MARINE MAMMALS ARE INVOLVED
Authors: Baker Troy L. , Jeansonne Jim , Henry Charlie , Tarpley John
Published: January 2013

Providing rapid and humane care for distressed or threatened marine mammals is crucial to the ultimate success of such actions. Recently, in the southeast United States, marine mammals were observed in the vicinity of several oil spills. Proper coordination of marine mammal rescue or recovery actions with the Unified Command (UC) is essential for response personnel safety and increased probability of saving the affected animals. In the event of animal mortalities, effective coordination between the marine mammal resource agencies and the UC helps ensure the preservation of causal evidence. National Oceanic and Atmospheric Administration'S (NOAA'S) Office of Response and Restoration (OR&R), generally through the NOAA Scientific Support Coordinator (SSC), is able to assist the Federal On-Scene Coordinator (FOSC) and UC in addressing the threat of spilled oil on potentially affected marine mammals. Response actions during recent spills included: documenting the animals’ type and location, notification of the marine mammal agencies and teams responsible for their recovery and care, and coordination between the spill response and the marine mammal response. The actions of responders during recent spills involving marine mammals are summarized and relevant issues discussed, including properly characterizing the threat to marine mammals from spilled oil. The recent oil spill responses involving marine mammals in the southeastern U.S. are applicable to future spills throughout the United States and potentially worldwide. These recent incidents underscore the need to fully understand and plan for high profile wildlife issues during oil spill responses.
Growing a Regional Planning and Response Toolkit
Authors: Martin Robert D. , Henry Charlie , Gill Mary , Goetzee William , Salinas Blanche
Published: January 2013

The Texas Coastal Oil Spill Planning and Response Toolkit (the Toolkit) was first introduced to the spill response community in 1999 on CDROM. Updated annually since that time, the Toolkit is now in its 12th edition and its contents now span Texas, Louisiana, Mississippi and Alabama. With 2,000 DVDs distributed annually, the Toolkit has become the most widely used vehicle for disseminating Area Contingency Plans (ACPs), Environmental Sensitivity Index (ESI) maps and almost 1,500 other spill planning and response documents in the USCG District 8 region. Navigating this extensive collection of PDF documents is managed by hyperlinks from a Master Page document which subdivides the contents into seven major categories: ACPs; ESI maps; Regional Response Team VI documents; Incident Command System (ICS) documents; software applications; internet links and additional documents. The “Additional Documents” category contains national and international response plans, oiled wildlife guidelines, as well as a wide variety of NOAA job aids, manuals and other useful reference materials. The Toolkit can be used for both planning and response activities. As a contingency plan or drill development resource, the Toolkit provides a convenient source of maps and detailed geographic response plans for use as the basis for scenario and plan development. Scenarios and plans developed from the Toolkit materials can be checked against the ACPs for compliance. During a spill event, the Toolkit also provides resources for: ICS spill management, setting protection priorities, reviewing Incident Action Plans for ACP compliance, guidance in executing pre-approval plans, and reviewing procedures for aerial reconnaissance (to name a few). Besides the obvious benefit of having these planning and response support resources in one convenient package, the Toolkit provides an additional benefit to the regional response community: a rallying point. The annual production of the Toolkit has created a schedule and framework around which state, Federal and private entities organize the annual updates to their ACPs through their Area Committees. This poster describes the Toolkit's growth over time, the manner in which it is used, the production workflow, the content selection philosophy and its impact on the spill response community.
California Marine Oil Spill Fisheries Closure: Key Processes of the Department of Fish and Game (DFG), Office of Spill Prevention and Response (OSPR), During a Fisheries Closure Event
Authors: Faurot-Daniels Ellen R. , Yamamoto Julie T. , Imai Randy H. , Klasing Susan A.
Published: January 2013

Determining whether to close a commercial, recreational, or subsistence fishery after an oil spill is a difficult emergency decision that must be made quickly by California state authorities. California state law now states that fisheries affected by a spill must be closed within 24 hours of a spill of one barrel (42 gallons) or more of oil, unless it can be determined that the actual risk is non-existent or has been mitigated. However, assessing the amount of oil truly spilled, the status of spilled oil containment versus spreading rate, and determining which fisheries are in the potential path of oil are all confounding factors. While the goal of the law is to protect people from consuming fish or shellfish that exceed established petroleum contaminant thresholds, caution is used to make sure fisheries are not closed unnecessarily. The California fishery closure protocol articulates the separate, specific, and coordinated roles and responsibilities of the Department of Fish and Game (DFG) and the Office of Environmental Health Hazard Assessment (OEHHA).

These protocols are internal to the two involved California state agencies, and are separate from any fishery closure decisions that might be made by the National Marine Fisheries Service for spills in federal waters.
Advancing Oil Spill Preparedness and Response Techniques for Arctic Conditions
Authors: Velez Peter , Johnsen Hanne Greiff , Steen Alexis , Osikilo Yvette
Published: January 2013

Industrial and commercial activities in Arctic and sub-Arctic regions, including oil exploration, have increased in recent years. The 2008 circumpolar analysis by the US Geological Survey highlighted the large quantities of undiscovered oil and gas (O&G) estimated to be present. Governments of Arctic coastal states require industry to ensure a high level of environmental protection while operating in these areas. There are unique considerations which must be addressed such as: prolonged periods of darkness and daylight, cold temperatures, environmental sensitivities, indigenous peoples and their culture, distant infrastructure and remoteness, presence of seasonal/dynamic sea ice offshore, and a generally higher cost of doing business. Oil spill response (OSR) in the ice-free season can be comparable to the response in others parts of the world, with the exception of lower temperatures and extended daylight hours. The latter is a distinct advantage for OSR operations.

Prevention of spills remains a top priority for industry. To address spills, if prevention is unsuccessful, the O&G industry has made significant progress over the last decades on addressing the technical challenges of operating in the Arctic. The O&G industry has also performed work to evaluate and validate OSR response measures under Arctic conditions. Oil spill response is a demanding task in any environment, but responding to spills in Arctic regions can present different challenges, especially with presence of sea ice, than to spills found in more temperate regions and opportunities exist to improve upon this existing capability. Some response techniques have been modified or specially developed for use in the Arctic. The O&G industry will undertake a joint industry research program to further address the challenges of Arctic Oil Spill Response. This paper describes the background, planning, and scope for this Joint Industry Program (JIP).
Persistence and Toxicity of Oil in Brackish Marshes Seven Years After the Chalk Point, Maryland Oil Spill
Authors: Michel Jacqueline , Nixon Zachary , Dahlin Jeffrey , Betenbaugh David , White Mark , Burton Dennis , Turley Steven
Published: January 2013

Seven years after the spill of an estimated 140,000 gallons of a mixture of No. 6 and No. 2 fuel oils into the Patuxent River, a study was conducted to assess recovery at 24 oiled sites compared with 24 unoiled sites. Metrics included stem density, stem height, belowground biomass and polynuclear aromatic hydrocarbons (PAH) at depths of 0–10 cm and 10–20 cm, and soil toxicity of the 0–10 cm interval.

Half of the soil samples contained the spilled oil; total PAHs varied by 1–2 orders of magnitude between the top and bottom intervals, reflecting high oil heterogeneity. The oil had lost 22–76% of its initial PAH content, although there had been little to no additional PAH weathering since Fall 2000 and Summer 2001. Stem density and height were significantly lower in oiled versus unoiled sites for Spartina alterniflora but not S. cynosuroides.

In contrast, belowground biomass was significantly lower in S. cynosuroides but not S. alterniflora. Based on toxicity tests and sediment quality benchmarks, 25% of the soils were expected to be toxic to many organisms (ESB-TUFCV values > 3.0; PMax > 0.65).

There are likely two factors limiting natural weathering processes in the marsh soils: slow physical removal processes and low oxygen availability.

The interior marsh habitat is flooded by daily tides through many small channels. The marsh surface has a lot of micro-topography with low areas between dense clumps of stems that hold pools of water during low tide. The sediments in these low areas are very soft and water saturated.

Obviously, during spring low tides, the marsh soils do drain as low as 30 cm, because the oil penetrated to these depths in some areas. The falling tide drains through dense vegetation. Tidal flushing may have been a mechanism for removal of bulk oil stranded on the surface initially; however, it would not be effective at mobilizing oil from below the marsh surface. There are few bioturbating benthic biota in these marshes. Photo-oxidation does not occur below ground. Therefore, the only other removal mechanism would be microbial degradation.
Spreading Agents Provide a New Oil Spill Response Option
Authors: Nedwed Tim , Canevari Gerard P. , Febbo Eric
Published: January 2013

This paper describes research on a new approach to oil spill response that utilizes a silicone-based spreading agent to cause thick oil slicks to spread to extremely thin sheens. The increased surface area of the thin sheens will enhance the evaporation of the oil. Although this requires additional study, we expect that any residual oil that remains after evaporation will be less toxic because the volatile components are also soluble and contain at least a component of oil toxicity. In addition, spreading the oil will reduce areal loading of the oil and result in very low concentrations of oil entering the water column if wave energy disperses the sheens.

Our tests established the ability of a silicone-based spreading agent to spread viscous oil to a thicknesses that was visually not detectable. Further, we found that treating a stable water-in-oil emulsion resulted in breaking of the emulsion and continued spreading to a thickness that was also visually not detectable. We believe the emulsion was broken when the thickness of the oil became less than the diameter of the emulsified water droplets.

The new response approach is a method of reducing the impacts of offshore marine oil spills by promoting rapid spreading of the oil. This in turn increases evaporation rates, breaks emulsions, and potentially enhances natural dispersion of residual oil. The final result is less hydrocarbon transferred to the water column and reduced toxicity of the hydrocarbon that is transferred.
A NIR‐II‐Emissive Organic Nanomedicine with Biomimetic Engineering for High‐Contrast Targeted Bioimaging and Multiple Phototherapies of Pancreatic Tumors
Authors: Wang Yiwei , Zhang Jie , Wang Yu , Yu Jie , Gao Yijian , Yang Yuliang , Li Xiliang , Wang Hongcheng , Li Shengliang
Published: July 2024

Recent advances are achieved in the design and development of efficient organic photosensitizers (PSs), especially with fluorescence imaging navigation in the second near‐infrared (NIR‐II, 1000–1700 nm) region. However, there are simply a handful of NIR‐II emissive organic PSs with efficient oxygen‐independent capability due to the scarcity of high‐performance NIR‐responsive organic materials and targeted delivery. Herein, a NIR‐II‐emissive organic nanomedicine with biomimetic engineering for high‐performance NIR‐II imaging and targeted multiple phototherapies of pancreatic tumors is reported. An A‐D‐A‐type conjugated small‐molecule TPC is designed and used to prepare water‐dispersive nanoparticles, which demonstrated high efficiency for type I and type II photodynamic performances, good photothermal conversion of 57%, and bright NIR‐II emission with a quantum yield of 9.8% under 808 nm light irradiation. With pancreatic cancer cell membrane camouflage, the biomimetic TPC nanomedicine achieved high‐resolution and targeted bioimaging of whole‐body blood vessels and tumors. Antitumor experiments demonstrated the high efficiency of the biomimetic TPC nanomedicine for pancreatic tumor elimination and good biosafety with 808 nm light irradiation. This work demonstrated a NIR‐II‐emissive versatile nanomedicine with enhanced tumor‐targeting for high‐resolution NIR‐II bioimaging and superior phototheranostics, providing a feasible idea for the evolution of targeted and high‐performance theranostics.
Plasmonic Hot Carrier‐Driven Photoelectrochemical Processes: Principle, Detection and Application
Authors: Song Kyoungjae , Roh Yujin , Park Hyewon , Park Jeong Young
Published: July 2024

Utilizing hot carriers induced by surface plasmon resonance in solar energy conversion to chemical fuels is a crucial issue in the field of photocatalysis. To achieve practical efficiency in plasmonic hot carrier application to photocatalysts, it is essential to theoretically and experimentally understand the generation, relaxation, and transfer of hot carriers. Photoelectrochemical (PEC) processes can offer a pathway to investigate the transfer dynamics of hot electrons (or hot holes) and enhance the efficiency of both hot carrier transfer and catalytic activity. This work summarizes a theoretical and experimental understanding of the hot carrier effect, emphasizing the hot carrier transfer dynamics to investigate the exact role of hot carriers in PEC reactions. The principles of hot carrier detection, diverse applications of hot carrier‐based photocatalysis, and perspectives for possible future progress are discussed.
Aptasensors and Advancement in Molecular Recognition Technology
Authors: Napit Rajindra , Jaysawal Satendra Kumar , Chowdhury Rocky , Catague Jasmine , Melke Haben , Pham Cuong Viet , Xu Huo , Jia Lee , Lin Jia , Hou Yingchu , Duan Wei
Published: July 2024

Synthetic oligonucleic acids known as aptamers exhibit remarkable selectivity and affinity for target recognition and binding. Selected via an iterative process known as “selective evolution of ligands by exponential enrichment” (SELEX), aptamers fold into defined 3D conformations to interact with their targets. The incorporation of aptamers as recognition elements has driven notable progress in biosensors, giving rise to the development of aptasensors. Here, the process of aptamer discovery and the development of various types of aptasensors are summarized. The fundamental design principles of aptasensors are elaborated along with the superiority of aptamers compared to antibodies. The various modes employed by aptasensors, such as structure‐switching design, hybridization chain reaction amplification, enzyme‐assisted recycling, and split aptamer design are examined. Further light is shed on the diverse landscape of aptasensors, their adaptability to different analytes aptasensors as well as their potential to propel advancements in modern biosensor technology. As a nucleic acids‐based biosensor platform, aptasensors poise to become a next generation of sensitive and cost‐effective technology to shape the future of molecular recognition in biosensing.
Formal Olefinic C−H Phosphinylation via Alkenyl Sulfonium Salts
Authors: Ma Juan , Lin Jie , Li Mingrui , Wang Liandi , Wu Kaikai , Zhou Yong‐Gui , Yu Zhengkun
Published: July 2024

Formal olefinic C−P cross‐coupling between alkenyl sulfonium salts and secondary phosphine oxides and H‐phosphinates has been developed. A base enables construction of alkenyl C−P bonds as well as aliphatic C−P bonds at ambient temperature under an air atmosphere. This protocol provides an alternative access to multisubstituted alkenyl phosphine oxides and phosphinates in 40–99% yield from functionalized alkenes through an interrupted Pummerer activation/base‐promoted olefinic C−S bond phosphinylation sequence. Gram‐scale preparation and feasible derivatization demonstrated the applicability of the resultant alkenylphosphine oxides.
Copper(II)‐Catalyzed [2+2+2] Annulation of Enaminones with Maleimides Using a Traceless Directing Group Strategy
Authors: Fu Leiqing , Huang Hongxiang , Jiang Yingying , Liu Xuan , Chen Huimin , Wan Jie‐Ping
Published: July 2024

A copper‐catalyzed annulation of enaminones with maleimides was developed to synthesize various pyrrolo[3,4‐e]isoindoles. In this strategy, 2‐aminopyridine served as a traceless directing group, and target products were obtained in 54–72% yields. Moreover, a plausible mechanism for this reaction was proposed based on several control experiments, deuterium exchange experiments, and previous reports.
Disproportionation and Transalkylation of Phenol and Dimethylphenol on Zeolite Catalysts
Authors: Mao Junyu , Liu Naiwang , Meng Xuan , Shi Li
Published: July 2024

Substantial amounts of phenolic compounds are present in medium‐low temperature coal tar (MLCT), of which dimethylphenol (DMP) is not as valuable to be utilized as the more abundant cresol due to its complex composition and difficulty in isolation. In this study, the disproportionation and transalkylation reactions of MLCT‐related model compound, i.e., 2,6‐DMP, in phenol over zeolite catalysts are investigated using a fixed‐bed reactor for sustainable new option to utilize MLCT‐derived phenolic mixtures. Reactivity is promoted at high temperatures and associated with zeolite acidity and pore structure. Since disproportionation and transalkylation reactions have certain spatial requirements, the micropores of MFI‐type zeolite may cause spatial barriers that make it difficult to carry out the reactions. MCM‐22, characterized by MWW‐type zeolite, maximized the conversion of 2,6‐DMP due to its strong Bronsted acidity and large mesopore volume. FAU‐type zeolite HY with a 3D large 12‐ring through‐channel shows relatively small spatial confinement and certain molecular sieving ability, which enables bimolecular reactions while allowing cresols to flow out of the pores efficiently to obtain the highest cresol selectivity. The addition of phenol significantly inhibits the spontaneous disproportionation of 2,6‐DMP to tricresol. Besides, o‐cresol dominate the cresol products, suggesting that the selectivity of o‐cresol is kinetically controlled.
Nitrogen‐Doped Carbon‐Encapsulated Nickel Nanoparticle Catalysts Using Covalent Organic Frameworks as Templates for Electrochemical CO2 Conversion
Authors: Zhao Yuzhen , Yu Xinxin , Wu Zhuangzhuang , Li Yongpeng , Wang Wenxin , Feng Lijuan , Sui Zhuyin , Chen Qi
Published: July 2024

Electrochemical CO2 reduction (ECR) reactions, powered by cleaner energy, possess significant promise in mitigating CO2 emissions and achieving carbon recycling. Herein, Ni@N‐C electrocatalysts with encapsulated structures are prepared using covalent organic frameworks (COFs) as templates, where COF‐derived nitrogen‐doped carbon (N‐C) is utilized to wrap Ni nanoparticles. At the potential of −0.97 V vs. RHE, 2Ni@N‐C‐800 is characterized by a high current density (j = 24.2 mA cm‐2) and relatively high CO Faraday efficiency (FECO = 72%), reflecting its good catalytic activity. The ECR performance of 2Ni@N‐C‐800 is due to the cooperative interaction between Ni nanoparticles and the N‐C structure, which is inferred from control and poisoning measurements. This study provides a new idea for finding efficient and stable ECR catalysts.
Engineering Versatile Bacteria‐Derived Outer Membrane Vesicles: An Adaptable Platform for Advancing Cancer Immunotherapy
Authors: Luo Ziheng , Cheng Xiang , Feng Bin , Fan Duoyang , Liu Xiaohui , Xie Ruyan , Luo Ting , Wegner Seraphine V. , Ma Dayou , Chen Fei , Zeng Wenbin
Published: July 2024

In recent years, cancer immunotherapy has undergone a transformative shift toward personalized and targeted therapeutic strategies. Bacteria‐derived outer membrane vesicles (OMVs) have emerged as a promising and adaptable platform for cancer immunotherapy due to their unique properties, including natural immunogenicity and the ability to be engineered for specific therapeutic purposes. In this review, a comprehensive overview is provided of state‐of‐the‐art techniques and methodologies employed in the engineering of versatile OMVs for cancer immunotherapy. Beginning by exploring the biogenesis and composition of OMVs, unveiling their intrinsic immunogenic properties for therapeutic appeal. Subsequently, innovative approaches employed to engineer OMVs are delved into, ranging from the genetic engineering of parent bacteria to the incorporation of functional molecules. The importance of rational design strategies is highlighted to enhance the immunogenicity and specificity of OMVs, allowing tailoring for diverse cancer types. Furthermore, insights into clinical studies and potential challenges utilizing OMVs as cancer vaccines or adjuvants are also provided, offering a comprehensive assessment of the current landscape and future prospects. Overall, this review provides valuable insights for researchers involved in the rapidly evolving field of cancer immunotherapy, offering a roadmap for harnessing the full potential of OMVs as a versatile and adaptable platform for cancer treatment.
DHPS‐Mediated Hypusination Regulates METTL3 Self‐m6A‐Methylation Modification to Promote Melanoma Proliferation and the Development of Novel Inhibitors
Authors: Guo Jing‐si , Ma Jian , Zhao Xi‐he , Zhang Ji‐fang , Liu Kai‐li , Li Long‐tian , Qin Yu‐xi , Meng Fan‐hao , Jian Ling‐yan , Yang Yue‐hui , Li Xin‐yang
Published: July 2024

Discovering new treatments for melanoma will benefit human health. The mechanism by which deoxyhypusine synthase (DHPS) promotes melanoma development remains elucidated. Multi‐omics studies have revealed that DHPS regulates m6A modification and maintains mRNA stability in melanoma cells. Mechanistically, DHPS activates the hypusination of eukaryotic translation initiation factor 5A (eIF5A) to assist METTL3 localizing on its mRNA for m6A modification, then promoting METTL3 expression. Structure‐based design, synthesis, and activity screening yielded the hit compound GL‐1 as a DHPS inhibitor. Notably, GL‐1 directly inhibits DHPS binding to eIF5A, whereas GC‐7 cannot. Based on the clarification of the mode of action of GL‐1 on DHPS, it is found that GL‐1 can promote the accumulation of intracellular Cu2+ to induce apoptosis, and antibody microarray analysis shows that GL‐1 inhibits the expression of several cytokines. GL‐1 shows promising antitumor activity with good bioavailability in a xenograft tumor model. These findings clarify the molecular mechanisms by which DHPS regulates melanoma proliferation and demonstrate the potential of GL‐1 for clinical melanoma therapy.
Designing Plastrons for Underwater Bubble Capture: From Model Microstructures to Stochastic Nanostructures
Authors: Wong William S. Y. , Naga Abhinav , Armstrong Tobias , Karunakaran Bhuvaneshwari , Poulikakos Dimos , Ras Robin H. A.
Published: July 2024

Bubbles and foams are often removed via chemical defoamers and/or mechanical agitation. Designing surfaces that promote chemical‐free and energy‐passive bubble capture is desirable for numerous industrial processes, including mineral flotation, wastewater treatment, and electrolysis. When immersed, super‐liquid‐repellent surfaces form plastrons, which are textured solid topographies with interconnected gas domains. Plastrons exhibit the remarkable ability of capturing bubbles through coalescence. However, the two‐step mechanics of plastron‐induced bubble coalescence, namely, rupture (initiation and location) and subsequent absorption (propagation and drainage) are not well understood. Here, the influence of 1) topographical feature size and 2) gas fraction on bubble capture dynamics is investigated. Smaller feature sizes accelerate rupture while larger gas fractions markedly improve absorption. Rupture is initiated solely on solid domains and is more probable near the edges of solid features. Yet, rupture time becomes longer as solid fraction increases. This counterintuitive behavior represents unexpected complexities. Upon rupture, the bubble's moving liquid‐solid contact line influences its absorption rate and equilibrium state. These findings show the importance of rationally minimizing surface feature sizes and contact line interactions for rapid bubble rupture and absorption. This work provides key design principles for plastron‐induced bubble coalescence, inspiring future development of industrially‐relevant surfaces for underwater bubble capture.
Flexoelectricity Modulated Electron Transport of 2D Indium Oxide
Authors: Hu Xinyi , Yu Chen Guan , Luan Yange , Tang Tao , Liang Yi , Ren Baiyu , Chen Liguo , Zhao Yulong , Zhang Qi , Huang Dong , Sun Xiao , Cheng Yin Fen , Ou Jian Zhen
Published: July 2024

The phenomenon of flexoelectricity, wherein mechanical deformation induces alterations in the electron configuration of metal oxides, has emerged as a promising avenue for regulating electron transport. Leveraging this mechanism, stress sensing can be optimized through precise modulation of electron transport. In this study, the electron transport in 2D ultra‐smooth In2O3 crystals is modulated via flexoelectricity. By subjecting cubic In2O3 (c‐In2O3) crystals to significant strain gradients using an atomic force microscope (AFM) tip, the crystal symmetry is broken, resulting in the separation of positive and negative charge centers. Upon applying nano‐scale stress up to 100 nN, the output voltage and power values reach their maximum, e.g. 2.2 mV and 0.2 pW, respectively. The flexoelectric coefficient and flexocoupling coefficient of c‐In2O3 are determined as ≈0.49 nC m−1 and 0.4 V, respectively. More importantly, the sensitivity of the nano‐stress sensor upon c‐In2O3 flexoelectric effect reaches 20 nN, which is four to six orders smaller than that fabricated with other low dimensional materials based on the piezoresistive, capacitive, and piezoelectric effect. Such a deformation‐induced polarization modulates the band structure of c‐In2O3, significantly reducing the Schottky barrier height (SBH), thereby regulating its electron transport. This finding highlights the potential of flexoelectricity in enabling high‐performance nano‐stress sensing through precise control of electron transport.
The LIDPAD Mouse Model Captures the Multisystem Interactions and Extrahepatic Complications in MASLD
Authors: Low Zun Siong , Chua Damien , Cheng Hong Sheng , Tee Rachel , Tan Wei Ren , Ball Christopher , Sahib Norliza Binte Esmail , Ng Ser Sue , Qu Jing , Liu Yingzi , Hong Haiyu , Cai Chaonong , Rao Nandini Chilagondanahalli Lakshmi , Wee Aileen , Muthiah Mark Dhinesh , Bichler Zoë , Mickelson Barbara , Kong Mei Suen , Tay Vanessa Shiyun , Yan Zhuang , Chen Jiapeng , Ng Aik Seng , Yip Yun Sheng , Vos Marcus Ivan Gerard , Tan Nicole Ashley , Lim Dao Liang , Lim Debbie Xiu En , Chittezhath Manesh , Yaligar Jadegoud , Verma Sanjay Kumar , Poptani Harish , Guan Xue Li , Velan Sambasivam Sendhil , Ali Yusuf , Li Liang , Tan Nguan Soon , Wahli Walter
Published: July 2024

Metabolic dysfunction‐associated steatotic liver disease (MASLD) represents an impending global health challenge. Current management strategies often face setbacks, emphasizing the need for preclinical models that faithfully mimic the human disease and its comorbidities. The liver disease progression aggravation diet (LIDPAD), a diet‐induced murine model, extensively characterized under thermoneutral conditions and refined diets is introduced to ensure reproducibility and minimize species differences. LIDPAD recapitulates key phenotypic, genetic, and metabolic hallmarks of human MASLD, including multiorgan communications, and disease progression within 4 to 16 weeks. These findings reveal gut‐liver dysregulation as an early event and compensatory pancreatic islet hyperplasia, underscoring the gut‐pancreas axis in MASLD pathogenesis. A robust computational pipeline is also detailed for transcriptomic‐guided disease staging, validated against multiple harmonized human hepatic transcriptomic datasets, thereby enabling comparative studies between human and mouse models. This approach underscores the remarkable similarity of the LIDPAD model to human MASLD. The LIDPAD model fidelity to human MASLD is further confirmed by its responsiveness to dietary interventions, with improvements in metabolic profiles, liver histopathology, hepatic transcriptomes, and gut microbial diversity. These results, alongside the closely aligned changing disease‐associated molecular signatures between the human MASLD and LIDPAD model, affirm the model's relevance and potential for driving therapeutic development.
Automated Scanning Dielectric Microscopy Toolbox for Operando Nanoscale Electrical Characterization of Electrolyte‐Gated Organic Transistors
Authors: Tanwar Shubham , Millan‐Solsona Ruben , Ruiz‐Molina Sara , Mas‐Torrent Marta , Kyndiah Adrica , Gomila Gabriel
Published: July 2024

Electrolyte‐gated organic transistors (EGOTs) leveraging organic semiconductors' electronic and ionic transport characteristics are the key enablers for many biosensing and bioelectronic applications that can selectively sense, record, and monitor different biological and biochemical processes at the nanoscale and translate them into macroscopic electrical signals. Understanding such transduction mechanisms requires multiscale characterization tools to comprehensively probe local electrical properties and link them with device behavior across various bias points. Here, an automated scanning dielectric microscopy toolbox is demonstrated that performs operando in‐liquid scanning dielectric microscopy measurements on functional EGOTs and carries out extensive data analysis to unravel the evolution of local electrical properties in minute detail. This paper emphasizes critical experimental considerations permitting standardized, accurate, and reproducible data acquisition. The developed approach is validated with EGOTs based on blends of organic small molecule semiconductor and insulating polymer that work as accumulation‐mode field‐effect transistors. Furthermore, the degradation of local electrical characteristics at high gate voltages is probed, which is apparently driven by the destruction of local crystalline order due to undesirable electrochemical swelling of the organic semiconducting material near the source electrode edge. The developed approach paves the way for systematic probing of EGOT‐based technologies for targeted optimization and fundamental understanding.