bluuebunny/crossref_metadata_2025 huggingface dataset:
Toughening Brittle Bio‐P3HB with Synthetic P3HB of Engineered Stereomicrostructures
Authors: Zhang Zhen , Quinn Ethan C. , Olmedo‐Martínez Jorge L. , Caputo Maria Rosaria , Franklin Kevin A. , Müller Alejandro J. , Chen Eugene Y.‐X.
Published: October 2023

Poly(3‐hydroxybutyrate) (P3HB), a biologically produced, biodegradable natural polyester, exhibits excellent thermal and barrier properties but suffers from mechanical brittleness, largely limiting its applications. Here we report a mono‐material product design strategy to toughen stereoperfect, brittle bio or synthetic P3HB by blending it with stereomicrostructurally engineered P3HB. Through tacticity ([mm] from 0 to 100 %) and molecular weight (Mn to 788 kDa) tuning, high‐performance synthetic P3HB materials with tensile strength to ≈30 MPa, fracture strain to ≈800 %, and toughness to 126 MJ m−3 (>110× tougher than bio‐P3HB) have been produced. Physical blending of the brittle P3HB with such P3HB in 10 to 90 wt % dramatically enhances its ductility from ≈5 % to 95–450 % and optical clarity from 19 % to 85 % visible light transmittance while maintaining desirably high elastic modulus (>1 GPa), tensile strength (>35 MPa), and melting temperature (160–170 °C). This P3HB‐toughening‐P3HB methodology departs from the traditional approach of incorporating chemically distinct components to toughen P3HB, which hinders chemical or mechanical recycling, highlighting the potential of the mono‐material product design solely based on biodegradable P3HB to deliver P3HB materials with diverse performance properties.
Geometrically Compelled Silicon(II)/Silicon(IV) Donor–Acceptor Interaction Enables the Enamination of Nitriles
Authors: Kong Deliang , Li Jiancheng , Dai Wen , Jiang Liuying , Zhao Yiling , Zhu Hongping , Fu Gang , Roesky Herbert W.
Published: October 2023

Discovering new bonding scenarios and subsequently exploring the reactivity contribute substantially to advance the main group element chemistry. Herein, we report on the isolation and characterization of an intriguing class of the hydrido‐benzosiloles 2–4. These compounds exhibit a side arm of the amidinatosilylenyl group, featuring unidirectional silicon(II)/silicon(IV) donor‐acceptor interaction on account of the geometric constraint. Furthermore, the reactions involving 2–4 with nitriles yield the tricyclic compounds that edge‐fused of the Si‐heteroimidazolidine‐CN2Si2, silole‐C4Si, and phenyl‐C6‐rings (5–13). These compounds are manifesting a unique reaction that the silicon(II)/silicon(IV) interaction enables the enamination of the α‐H‐bearing nitriles. The reaction mechanism involved in H‐shift under oxidative addition at silylene followed by hydrosilylation of a ketenimine intermediate was revealed by density function theory (DFT) calculations.
High‐pressure high‐temperature fluid displacement by foam injection within a multiblock matrix‐fracture system
Authors: Fathollahi Alireza , Khosravi Maryam , Rostami Behzad , Saeibehrouzi Ali , Hassani Kamran
Published: October 2023

Foam injection has been suggested and demonstrated as a potential gas‐based solution for enhancing oil recovery from underground reservoirs. While the pore‐scale behavior of foam has been investigated for many years, most of those studies were done at room temperature and pressure. A high‐pressure high‐temperature (HPHT) cell was constructed to relax this contributing simplification and evaluate foam behavior under reservoir conditions. The performance of foam injection into a fractured reservoir was investigated experimentally at vertical and horizontal pathways utilizing a 2D microfluidic device. The results showed foam had a higher lamellae density in the fracture network and could direct fluids to the matrix. This was mainly attributed to the created pressure drop in the fractured media dictated by foam self‐tuning ability, which is a higher viscosity in areas with higher conductivity. Generating a viscous crossflow in horizontal tests leads to enhanced recovery relative to gas injection. But the presence of gravity in the vertical tests causes the drainage of the foam film and the segregation of the gas and surfactant solution due to gravity, which ultimately reduces the stability of the foam. Comparing the performance of gas and foam in the vertical injection scenario reveals that foam injection results in a considerably more enhanced oil recovery. The oleic phase had a detrimental impact on foam strength and reduced fluids diversion from fracture to matrix. The sizes of gas bubbles were also larger in the presence of the oleic phase.
Zygomatic arch root position in relation to dietary type in haplorhine primates
Authors: Edmonds Hallie M. , Daly E. Susanne , Smail Irene E.
Published: October 2023

The zygomatic root, along with other key craniofacial features, is hypothesized to play a crucial role in strengthening the face in response to stresses and strains related to feeding. As such, it has been cited as indicative of dietary specialization among fossil taxa, although it remains unknown how variable zygomatic arch root position is among living primates, and whether its positioning predicts differences in diet. We test whether primates that consume more mechanically challenging foods possess more anteriorly positioned zygomatic roots compared to those consuming less challenging foods. Zygomatic root position, as defined by the zygomaxillare landmark, was identified and recorded from digital images and physical specimens of adult primate crania. Data were collected from 33 haplorhine species (n = 722). Published data were used to assign species to a dietary type based on patterns of overall consumption along with reliance on especially challenging foods. Pairwise comparisons between mechanically challenging (hard and/or tough) and less mechanically challenging (soft) consumers found significant differences (p < 0.05) in the position of the zygomatic root in 17 of 20 pairs, 11 of which supported the prediction that a more mechanically challenging diet is associated with a more anteriorly placed zygomatic root. PGLS analysis found no significant effect of phylogeny on root position. This suggests that a more anteriorly positioned zygomatic root is useful for identifying dietary specialization in some taxa but is not required for consuming a mechanically challenging diet given that other craniofacial and behavioral factors can facilitate the consumption of such foods.
Verbindungen mit Nägeln im Holzbau – die Erforschung und Entwicklung von Konstruktionsregeln
Authors: Fischer Jens , Schwendner Sascha , Seim Werner , Engelmann Iris
Published: October 2023

Der metallische Nagel als tragendes Verbindungsmittel in Holzkonstruktionen ist heute weitverbreitet. Doch noch vor 100 Jahren war das anders: sein statisch konstruktiver Gebrauch war in Deutschland nicht normativ geregelt. Das änderte sich Ende der 1920er‐Jahre, als damit begonnen wurde, genagelte Verbindungen systematisch zu erforschen. Seit 1933 ist der Nagel Bestandteil der deutschen Regelwerke und findet seitdem breite Verwendung. Über weite Teile des 20. Jahrhunderts diente er in Not‐ und Sparkonstruktionen wie Brett‐ und Bohlenbindern als hocheffizientes Verbindungsmittel der Wahl. Diese materialsparenden Tragwerke waren in Zeiten wiederkehrender Ressourcenknappheit sehr gefragt und gehören damit zur Konstruktionsgeschichte des Holzbaus. In diesem Beitrag wird über die Forschung zur Anwendung von Nägeln in Holzkonstruktionen und die einhergehend fortlaufende Normierung berichtet. Die stufenweisen Fortschritte werden vorgestellt. Anhand eines Zeitstrahls werden Zusammenhänge zwischen Forschung und Normung gezeigt. Tabellen und Grafiken verdeutlichen die Änderungen innerhalb der Normen von der ersten DIN 1052 im Jahr 1933 über die erste eigenständige Holzbaunorm in der DDR, die TGL 112‐0730, aus 1963 bis zur DIN 1052‐1988. Abschließend wird Bezug zum derzeitigen Entwurf des Eurocode 5 genommen. Allgemein zeigt sich, dass ein Großteil der heute immer noch gültigen Kenntnisse auf die Grundlagenforschung der 1930er‐Jahre zurückgeht.
Nägel im Holzbau – die Erforschung des Trag‐ und Verformungsverhaltens
Authors: Schwendner Sascha , Fischer Jens , Seim Werner , Engelmann Iris
Published: October 2023

Die Tragfähigkeit von Nägeln (Drahtstifte) und Nagelverbindungen im Holzbau war lange Zeit ausschließlich über Tabellen, die auf experimentellen Untersuchungen basierten, geregelt. In den letzten 100 Jahren untersuchten unterschiedliche Forscher das Last‐Verformungsverhalten dieser Verbindungen und entwickelten Modelle, mit denen auf Grundlage von analytischen Gleichungen die Tragfähigkeit und das Verformungsverhalten von Nägeln berechnet werden können. Die zunächst in Not‐ und Sparkonstruktionen eingesetzten Nägel werden heutzutage v. a. im Holztafelbau verwendet. Im Bestand finden sich aber auch zahlreiche, teils weitgespannte Fachwerkkonstruktionen, deren Tragsicherheit auf den genagelten Verbindungen in den Knotenpunkten basiert. In dem folgenden Beitrag wird die Erforschung und Entwicklung des Trag‐ und Verformungsverhaltens von Holz‐Holz‐Verbindungen mit Nägeln als Verbindungsmittel chronologisch und detailliert erläutert. Die entsprechenden Meilensteine werden genauer betrachtet. Unterschiedliche Methoden für die Bestimmung der Tragfähigkeit werden vorgestellt. Auf mechanische Phänomene, die nach und nach erforscht wurden, wird eingegangen. Mit dem heute erreichten Stand des Wissens können vielfältige Verbindungen nachgewiesen werden. Zudem ist es möglich, deren Steifigkeit explizit zu bestimmen. Tabellen und Grafiken verdeutlichen die einzelnen Meilensteine der geschichtlichen Entwicklung und vergleichen konkret die unterschiedlichen normativen Regelungen seit Beginn der Einführung des Nagels in den Ingenieurholzbau in Deutschland. Hierbei kann gezeigt werden, dass es trotz unterschiedlicher Herangehensweisen seit 1933 kaum Änderungen bei den Ergebnissen der rechnerischen Bestimmung der Tragfähigkeit gibt.
Distributed generator and capacitor‐embedded reconfiguration in three‐phase unbalanced distribution systems using teaching learning‐based optimization
Authors: Mehroliya Shweta , Arya Anoop
Published: October 2023

In the transmission and distribution networks, both active and reactive power play significant roles. While active power does the beneficial work, reactive power maintains the voltage that necessitates management from a system reliability perspective. The voltage variation from the nominal range may result in unintentional operation and early component failure. To maximize the amount of real power that can be transported over the power‐transmitting media, the system must also control reactive power flow. In a three‐phase unbalanced distribution system reinforced with distributed generator units (DGUs) and shunt capacitor units (SCUs), this paper suggests a teaching learning‐based optimization (TLBO) approach to be applied to combinatorial problems for simultaneous reduction of real power loss and net reactive power flow, enhance voltage stability index (VSI) and minimize aggregated voltage deviation index. A multiobjective formulation based on TLBO has been implemented to choose the ideal sizes and placements of DGUs and SCUs in large distribution networks. The case studies have been carried out on an IEEE 33‐bus standard system and a large 123‐bus unbalanced system. The analysis of the IEEE 33‐ and 123‐bus test systems reveals the economic efficiency of the suggested TLBO algorithm. Notably, by applying DG and capacitor simultaneously in the 33‐bus system, a significant reduction of 59.35%, 55.05%, and 50.76% (phases a, b, and c), and for the 123‐bus system, a significant reduction of 43.65%, 19%, and 48.65% (phases a, b, and c) in total active power losses have been achieved. The results suggest that the proposed method renders significant improvement in voltage stability and reduces power losses concerning the base case for both test systems.
Learning the value of additional learning
Authors: Skipworth Stan
Published: October 2023

After what I’ve affectionately referred to as a bit of a “gap year,” I’m back working in higher education campus safety fulltime. While I’ve been able to enjoy the opportunity to venture into some select security consulting and assessment work during this time, I’ve remained confident that I would like to re‐engage within a leadership role once more in higher education. In particular, I knew I’d like to re‐engage with a leadership role in higher education within a public safety department, perhaps to include the familiar concurrent oversight of parking, emergency services management, and special events security.
Electrodeposition of Manganese Dioxide under Different Conditions: Application of MnO2/Carbon Fibers in the Electrosorption Process
Authors: Issa Zainab M. , Salman Rasha H.
Published: October 2023

Anodic electrodeposition was used to synthesize a composite electrode of nanostructured manganese dioxide/carbon fiber (CF) galvanostatically. Different characterization results of the nanostructured MnO2 were obtained by varying the H2SO4 concentration and the current density. Field emission scanning electron microscopy, X‐ray diffraction, and atomic force microscopy were utilized to characterize the prepared composite electrodes. The best conditions were: 0.3 mA cm−2 current density and 0.64 M H2SO4 concentration. The electrosorption performance of the MnO2/CF electrode prepared under the best conditions was tested by way of its chromium(VI) ion adsorption from a simulated solution. The applied voltage, pH, and ionic strength affect the efficiency of Cr(VI) ion removal. The highest chromium removal efficiency was 99.98 %, achieved at pH 2, a cell voltage of 4.6 V, and a NaCl concentration of 1 g L−1.
Visible Light Mediated Co‐Catalyzed Isocyanide Insertion with Sulfonyl Azide: Synthesis of Sulfonyl Carbamimidic Azide and Sulfonyl Aminotetrazole via Carbodiimide Intermediate
Authors: Ravindra Sundaresan , Natarajan Kannan , Padma Priya Vetrivel R. , Kataria Ramesh , Nandi Ganesh Chandra
Published: October 2023

Herein, we report an operationally simple and efficient protocol to prepare sulfonyl carbamimidic azide and N‐sulfonyl aminotetrazole via Co‐catalyzed three component coupling of sulfonyl azide (acts as nitrene source), isocyanide, and TMS‐azide at room temperature under visible light. Initially, the carbamimidic azide is formed, which cyclizes only in the presence of base to deliver N‐sulfonyl aminotetrazole in very good yields. The sulfonyl aminotetrazole can also be synthesized directly without isolating the carbamimidic azide in the presence of base. The sulfonyl azide is anticipated to generate nitrene and reacts with isocyanide to produce carbodiimide. Subsequent addition of azide (TMS‐N3) to carbodiimide results in the formation of carbamimidic azide.
Nitrogen‐Doped Starbons®: Methodology Development and Carbon Dioxide Capture Capability
Authors: Barker Ryan E. , Brand Michael C. , Clark James H. , North Michael
Published: October 2023

Five nitrogen sources (glycine, β‐alanine, urea, melamine and nicotinamide) and three heating methods (thermal, monomodal microwave and multimodal microwave) are used to prepare nitrogen‐doped Starbons® derived from starch. The materials are initially produced at 250–300 °C (SNx300y), then heated in vacuo to 800 °C to produce nitrogen‐doped SNx800y’s. Melamine gives the highest nitrogen incorporation without destroying the Starbon® pore structure and the microwave heating methods give higher nitrogen incorporations than thermal heating. The carbon dioxide adsorption capacities of the nitrogen‐doped Starbons® determined gravimetrically, in many cases exceed those of S300 and S800. The carbon dioxide, nitrogen and methane adsorption isotherms of the most promising materials are measured volumetrically. Most of the nitrogen‐doped materials show higher carbon dioxide adsorption capacities than S800, but lower methane and nitrogen adsorption capacities. As a result, the nitrogen‐doped Starbons® exhibit significantly enhanced carbon dioxide versus nitrogen and methane versus nitrogen selectivities compared to S800.
Deep learning methods for blood flow reconstruction in a vessel with contrast enhanced x‐ray computed tomography
Authors: Shusong Huang , Monica Sigovan , Bruno Sixou
Published: October 2023

The reconstruction of blood velocity in a vessel from contrast enhanced x‐ray computed tomography projections is a complex inverse problem. It can be formulated as reconstruction problem with a partial differential equation constraint. A solution can be estimated with the a variational adjoint method and proper orthogonal decomposition (POD) basis. In this work, we investigate new inversion approaches based on PODs coupled with deep learning methods. The effectiveness of the reconstruction methods is shown with simulated realistic stationary blood flows in a vessel. The methods outperform the reduced adjoint method and show large speed‐up at the online stage.
Transformation of CO2 to Carbon Nanotubes by Catalytic Chemical Vapor Deposition using a Metal‐Supported Hierarchical Zeolite Template
Authors: Nunthakitgoson Watinee , Rodaum Chadatip , Pornsetmetakul Peerapol , Wattanakit Chularat , Wattana Piyarat , Thivasasith Anawat
Published: October 2023

The conversion of CO2 into valuable substances is a topic of great interest in current research. Carbon nanotubes (CNT) have emerged as highly promising materials for CO2 conversion. In this study, we successfully developed a catalyst by loading active transition metals (Fe or Ni) onto hierarchical zeolite for CNT synthesis. Our catalyst demonstrated excellent performance under synthetic conditions. The most favorable CNT was obtained using the 25 wt.% FeHieFAU catalyst, which exhibited a diameter size of 23.1 nm, a CNT yield of 15.4 %, and an ID/IG ratio of 0.56, indicating high quality. Additionally, we investigated the beneficial effects of the synthesized CNT by testing their current response. Notably, the current response of the synthesized CNT surpassed that of commercial CNT when using a 0.5 M H2SO4 supporting electrolyte and cyclic voltammetry (V vs. Ag/AgCl). These findings highlight the significant contributions of the small diameter and superior quality of our synthesized pure CNT, which offer potential improvements in current response compared to commercial CNT. This research opens new avenues for utilizing CNT in CO2 conversion and electrochemical applications.
Cross‐sectional and longitudinal evaluation of plasma glial fibrillary acidic protein to detect and predict clinical syndromes of Alzheimer's disease
Authors: Ally Madeline , Sugarman Michael A. , Zetterberg Henrik , Blennow Kaj , Ashton Nicholas J. , Karikari Thomas K. , Aparicio Hugo J. , Frank Brandon , Tripodis Yorghos , Martin Brett , Palmisano Joseph N. , Steinberg Eric G. , Simkin Irene , Farrer Lindsay A. , Jun Gyungah R. , Turk Katherine W. , Budson Andrew E. , O'Connor Maureen K. , Au Rhoda , Goldstein Lee E. , Kowall Neil W. , Killiany Ronald , Stern Robert A. , Stein Thor D. , McKee Ann C. , Qiu Wei Qiao , Mez Jesse , Alosco Michael L.
Published: October 2023

Introduction

This study examined plasma glial fibrillary acidic protein (GFAP) as a biomarker of cognitive impairment due to Alzheimer's disease (AD) with and against plasma neurofilament light chain (NfL), and phosphorylated tau (p‐tau)181+231.

Methods

Plasma samples were analyzed using Simoa platform for 567 participants spanning the AD continuum. Cognitive diagnosis, neuropsychological testing, and dementia severity were examined for cross‐sectional and longitudinal outcomes.

Results

Plasma GFAP discriminated AD dementia from normal cognition (adjusted mean difference = 0.90 standard deviation [SD]) and mild cognitive impairment (adjusted mean difference = 0.72 SD), and demonstrated superior discrimination compared to alternative plasma biomarkers. Higher GFAP was associated with worse dementia severity and worse performance on 11 of 12 neuropsychological tests. Longitudinally, GFAP predicted decline in memory, but did not predict conversion to mild cognitive impairment or dementia.

Discussion

Plasma GFAP was associated with clinical outcomes related to suspected AD and could be of assistance in a plasma biomarker panel to detect in vivo AD.
Extreme precipitation promotes invasion in managed grasslands
Authors: Ratcliffe Hugh , Kendig Amy , Vacek Sara , Carlson Daren , Ahlering Marissa , Dee Laura E.
Published: October 2023

Climate change is increasing the frequency and intensity of extreme events like drought and flooding, which threaten to amplify other global change drivers such as species invasion. We investigate the effect of wet and dry extreme precipitation regimes on invasive species' abundances in northern tallgrass prairies. Because soil moisture is a key determinant of prairie composition, theory and evidence suggest drought conditions will hinder invasion, whereas wetter conditions will enhance invasion. To test this hypothesis, we explored the effect of precipitation on invasive plant species abundance from 2010 to 2019 in 25 managed prairies using observations from 267 transects comprising 6675 plots throughout western Minnesota, USA. We estimated how increases in the number of extremely wet or dry months in a year altered overall invasive species abundance and the abundance of the highly invasive grasses Poa pratensis and Bromus inermis. We found that a greater occurrence of abnormally wet months increased invasive species abundance but found mixed evidence that abnormally dry conditions hindered invasion. Further, more moderately wet and dry months reduced native grass abundance. Together, these results suggest that more frequent extremely wet months may intensify invasive dominance and that dry months may not counterbalance these trends. Given the considerable uncertainty still surrounding the interactive effects of climate change and invasion on native plant communities, this research represents an important step toward quantifying the complex influence of precipitation extremes on invasion dynamics in managed ecosystems of critical conservation concern.
Intra‐individual cortical networks in Anorexia Nervosa: Evidence from a longitudinal dataset
Authors: Collantoni Enrico , Alberti Francesco , Dahmen Brigitte , von Polier Georg , Konrad Kerstin , Herpertz‐Dahlmann Beate , Favaro Angela , Seitz Jochen
Published: October 2023

Objective

This work investigates cortical thickness (CT) and gyrification patterns in Anorexia Nervosa (AN) before and after short‐term weight restoration using graph theory tools.

Methods

38 female adolescents with AN underwent structural magnetic resonance imaging scans at baseline and after ‐ on average ‐ 3.5 months following short‐term weight restoration while 53 age‐matched healthy controls (HCs) were scanned once. Graph measures were compared between groups and longitudinally within the AN group. Associations with clinical measures such as age of onset, duration of illness, BMI standard deviation score (BMI‐SDS), and longitudinal weight changes were tested via stepwise regression.

Results

Cortical thickness graphs of patients with acute AN displayed lower modularity and small‐world index (SWI) than HCs. Modularity recovered after weight gain. Reduced global efficiency and SWI were observed in patients at baseline compared to HCs based on gyrification networks. Significant associations between local clustering of CT at admission and BMI‐SDS, and clustering/global efficiency of gyrification and duration of illness emerged.

Conclusions

Our results indicate a shift towards less organised CT networks in patients with acute AN. After weight recovery, the disarrangement seems to be partially reduced. However, longer‐term follow‐ups are needed to determine whether cortical organizational patterns fully return to normal.
Effect of Cichorium glandulosum on intestinal microbiota and bile acid metabolism in db/db mice
Authors: Yan Junlin , Zhang Rui , Kang Jinsen , Zhong Yewei , Abudurexiti Adalaiti , Tan Huiwen , Lei Yi , Ma Xiaoli
Published: October 2023

This study aims to investigate the effects of Chorum glandulosum Boiss. et Huet (CG) on the intestinal microbiota and serum bile acid (BA) in db/db mice. A total of 12 db/db mice were randomly divided into model (MOD), high‐dose CG (CGH), and control (CON) groups. The CON and MOD groups received distilled water by gavage for 8 weeks. Whereas, the CGH group received an alcohol extract of CG at a dose of 200 mg/kg/day. Results showed that CG can reduce blood lipid levels. It change the composition of the intestinal microbiota, and increase the relative abundances of Muribaculaceae, Prevotellaceae, Bifidobacterium_pseudolongum, Bacteroidaceae in db/db mice as well. LC–MS metabolomics results showed that CG adjusted the serum BA levels. The results reduced the levels of primary BAs, such as cholic acid (CA) and chenodeoxycholic acid (CDCA). The results decreased the primary BA/secondary BA (PSA/SBA) ratio in db/db mice. Correlation analysis showed that the abundances of Bifidobacterium_pseudolongum and Bacteroidaceae were positively correlated with acetic acid level and negatively correlated with ursocholic acid (UCA), α‐muricholic acid (αMCA), triglyceride (TG), and total cholesterol levels (TC), indicating an interaction between the intestinal microbiota and serum BAs. CG may play a positive role in the interaction between the intestinal microbiota and BAs in lipid metabolism.
Geomorphological and meteorological drivers of ephemeral pond hydrology in the Canadian shield forest
Authors: Roux Marjolaine , Larocque Marie , Nolet Philippe , Bizhanimanzar Mohammad
Published: October 2023

Ephemeral ponds in cold and humid forested regions are often vulnerable because of their small size and ephemeral nature. The aim of this study was to identify the geomorphological and meteorological drivers of ephemeral pond hydrology in the forests of cold and humid climates. A multi‐year study of 40 ponds was conducted in the Kenauk forest located in the Canadian Shield of the Outaouais region (Quebec, Canada). Pond bathymetry, mineral and organic sediment thickness, watershed area, slope, canopy cover and maximum depth were measured in‐situ. The spring hydroperiod (the period during which there is water in the ponds between April and October) as well as the surface and groundwater recession rates were measured throughout the study period, from 2016 to 2020. Data from this study show that ponds located at lower altitudes in the landscape are larger, receive water from a larger area, and have longer hydroperiods than ponds located at higher altitudes. The results demonstrated a connection between the ponds and the surrounding aquifer. Spring and early summer precipitation was shown to affect hydroperiods the most, while summer precipitation influenced the presence of water in the ponds from April to October. Winter precipitation appear determinant for pond recession rates. Simple multiple regression models were able to simulate hydroperiods and hydroperiod indices relatively well, but pond recession rates were not well represented by the models. This study brings original multi‐year and multi‐site data identifying parameters and variables that determine ephemeral pond hydrology in cold and humid climates. The results provide new insights into their resilience on the landscape and bring new arguments for their long‐term protection.
An evaluation of the psychometric properties of the strengths and difficulties scale in Turkey: Implications for other non‐WEIRD countries
Authors: Ruffman Ted , Selcuk Bilge , Yavus‐Muren H. Melis , Arikan Kubra , Tuncay Ipek
Published: October 2023

The Strengths and Difficulties Questionnaire (SDQ) is a very widely used scale in which parents, teachers or the child rate various aspects of the child's well‐being. It is widely used in the Western world and is translated into 80+ languages. It is also used in countries that do not classify as WEIRD (Western, educated, industrialized, rich and democratic). However, unlike WEIRD countries, some studies indicate that the psychometric properties of the SDQ when used in non‐WEIRD countries are questionable. Therefore, we gave the SDQ to the mothers and teachers of 310 3‐ to 5‐year‐olds in urban centres of Turkey and examined its psychometric properties. Turkey is not a WEIRD country because it is not Western, although the participants in our study were well educated, living in an industrialized area, rich relative to others in Turkey (although poor relative to Westerners) and democratic. As such, it is not drastically different from WEIRD countries and our question was whether even relatively small deviations from standard WEIRD criteria could result in questionable psychometric properties for the SDQ.
Front Cover Image
Authors: Bae Byungjoon , Baek Yongmin , Yang Jeongyong , Lee Heesung , Sonnadara Charana S. S. , Jung Sangeun , Park Minseong , Lee Doeon , Kim Sihwan , Giri Gaurav , Shah Sahil , Yoo Geonwook , Petri William A. , Lee Kyusang
Published: October 2023

Fast and accurate SARS‐CoV‐2 diagnosis based on simultaneous detection of antigen and antibody enhanced by near‐sensor neural network.

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Molecular Targets in Oncology: Implications of the Multidrug Resistance Gene
Authors: Lum Bert L. , Gosland Michael P. , Kaubisch Sonja , Sikic Branimir I.
Published: October 2023

The curative potential of chemotherapy for a number of tumor types has been obscured by the fact that many patients initially have striking remissions but later relapse and die. At the time of relapse many patients manifest resistance to a wide array of structurally unrelated antineoplastic agents, hence the term multidrug resistance (MDR). Other tumor types, such as those arising in the colon, kidneys, liver, and lungs, tend to exhibit poor response to available cytotoxic drugs. The MDR phenomenon includes cross‐resistance among the anthracyclines (doxorubicin, daunorubicin), the epipodophyllotoxins (etoposide, teniposide), the vinca alkaloids (vinblastine, vincristine), taxol, and other compounds. In vitro studies in cell culture indicate that this form of resistance is associated with amplification or overexpression of the mdrl gene. The mdrl gene codes for the expression of a cell surface protein, P‐glycoprotein (P‐gp), which acts as an energy‐dependent efflux pump that transports drugs associated with MDR out of the cell before cytotoxic effects occur. The protein is expressed in normal human tissues such as the gastrointestinal tract, liver, and kidneys, where it is thought to serve as an excretory pathway for xenobiotic drugs and toxins. Preliminary studies demonstrated the presence of P‐gp in tumor samples from patients with acute leukemia, multiple myeloma, lymphomas, and a variety of solid tumors. A number of drugs are able to reverse MDR, including calcium‐channel blockers, phenothiazines, quinidine, antimalarial agents, antiestrogenic and other steroids, and cyclosporine. Limited results from clinical trials with small numbers of patients suggest that the addition of verapamil, diltiazem, quinine, trifluoperazine, or cyclosporine to chemotherapeutic regimens has the potential to reverse MDR; however, toxicities limit their clinical usefulness. A number of trials are under way to identify more active and less toxic modulators of MDR.
Monoclonal Antibody Therapy for Gram‐Negative Sepsis: Principles, Applications, and Controversies
Authors: Mehra LIa V. , Gottlieb Jonathan E. , Nash David B.
Published: October 2023

Gram‐negative sepsis is a common event in hospitalized patients and is a leading cause of death in the United States. Endotoxin (lipopolysaccharide, LPS), a component of the cell wall of gram‐negative microorganisms, is responsible for the cascade of events leading to the sepsis syndrome consisting of fever, tachycardia, tachypnea, and evidence of organ hypoperfusion. The lipid A region of endotoxin produces most of these biologic and toxic effects. Monoclonal IgM antibodies directed against the lipid A portion of endotoxin (anti‐LPS MoAb) have been developed for the treatment of gram‐negative sepsis. Results of two large‐scale clinical trials suggest that these antibodies offer clinically and statistically significant reductions in mortality by a factor of about one‐third. However, in both trials, this apparent beneficial effect was limited to particular subsets of patients, and no overall benefit was seen. These considerations, in addition to the likely high cost of the agents, pose questions about their ultimate use in the treatment of patients with gram‐negative sepsis. Nevertheless, the logic of the approach, the demonstration of efficacy in disease models, and the advances in modern techniques of molecular biology all suggest that these or other closely related products will play a significant role in the treatment of this disorder.
The Effect of Isradipine on Theophylline Pharmacokinetics in Healthy Volunteers
Authors: Perreault Marc M. , Kazierad David J. , Wilton John H. , Izzo Joseph L.
Published: October 2023

The effects of isradipine 2.5 mg and 5 mg on the disposition of theophylline were investigated in a placebo‐controlled, randomized, three‐way, crossover trial. Eleven healthy, nonsmoking men each received a treatment of placebo, and isradipine 2.5 mg and 5 mg every 12 hours for 6 consecutive days. On the morning of day 6, 2 hours after the isradipine dose, theophylline (solution) 5.0 mg/kg was administered orally, and blood samples were collected over 24 hours. A 2‐week washout period separated treatment sequences. Plasma samples were analyzed for theophylline using high‐performance liquid chromatography. Using a two‐way analysis of variance, no significant changes in apparent theophylline clearance were observed between placebo, and isradipine 2.5 and 5 mg (0.815 ± 0.164, 0.870 ± 0.212, and 0.827 ± 0.164 ml/min/kg, respectively; p=0.136). Similarly, no significant change in volume of distribution was noted. These findings suggest that isradipine at recommended dosages does not impair theophylline metabolism.
Prescribing Considerations in Fluoroquinolone Therapy
Authors: Gentry Layne O.
Published: October 2023

Comparative trials have shown that the new oral fluoroquinolones are as effective as parenteral cephalosporins and other broad‐spectrum agents in treating infections of the urinary tract, lower respiratory tract, and skin and skin structure caused by most gram‐negative and selected gram‐positive pathogens. The agents are also effective in the treatment of prostatitis and osteomyelitis. Sequential parenteral to oral therapy has also proved useful, even in patients who are severely ill and are in intensive care units. This allows patients to be transferred out of intensive care earlier, reduces hospital stay and pharmacy costs, and improves quality of life. Because of the high bioavailability (>95%) of ofloxacin, oral and parenteral doses are identical.
The Drug Data Base of the Pawtucket Heart Health Program: Development and Description
Authors: Barbour Marilyn McFarland , Hume Anne Lamont , Assaf Annlouise R. , Carleton Richard A.
Published: October 2023

Pharmacoepidemiology has become an important tool for identifying patterns of drug use and adverse drug reactions in the general population. Drug data bases derived from population‐based samples have been particularly useful in addressing questions such as adherence to national guidelines for the treatment of chronic diseases. As part of the Pawtucket Heart Health Program, a continuing community‐based research and demonstration project, detailed information regarding the use of drugs among the general population of two southeastern New England cities was collected using cross‐sectional and longitudinal methodologies.
Influence of Hyperbaric Oxygen on the Pharmacokinetics of Single‐Dose Gentamicin in Healthy Volunteers
Authors: Merritt Gerald J. , Slade J. Benjamin
Published: October 2023

Study Objective. To determine the single‐dose pharmacokinetics of gentamicin in healthy humans undergoing hyperbaric oxygen (HBO) exposure.

Design. Randomized, crossover trial.

Setting. Specialized hyperbaric research facility within a United States Air Force medical center.

Subjects. Five healthy men between 28 and 43 years of age.

Interventions. Each subject received a total of two doses of intravenous gentamicin 1.5 mg/kg lean body weight spaced at least 2 weeks apart. One dose was infused under normobaric oxygen (NBO) conditions and the other under HBO conditions.

Measurements and Main Results. Gentamicin pharmacokinetic values were determined on 11 serum samples per subject collected sequentially out to 300 minutes after infusion. Using PCNONLIN, the following results demonstrated no difference between the pharmacokinetic values under HBO and NBO conditions, respectively: β half‐life (112, 115 min); volume of distribution (0.201, 0.184 L/kg); peak concentration (6.52, 7.23 mg/L); clearance (0.0754, 0.0676 L/kg/hr).

Conclusions. Hyperbaric oxygen produced no changes in the measured pharmacokinetic values of gentamicin under the conditions specified in this study. It is possible that numerous HBO exposures could produce a cumulative effect on gentamicin pharmacokinetics that would not be discernible in a single‐dose study. Because of the profound physiologic effects of HBO, drugs with narrow therapeutic indexes should be evaluated under HBO conditions if they are to be given to patients receiving HBO treatments.
Patterns of Acetaminophen Use in Alcoholic Patients
Authors: Seifert Charles F. , Lucas Dirk S. , Vondracek Thomas G. , Kastens Donald J. , McCarty David L. , Bui Bao
Published: October 2023

Alcoholics may be predisposed to the hepatotoxicity of acetaminophen due to increased activity of the cytochrome P‐450 system and decreased hepatic glutathione. To date, scattered case reports provide only a brief sketch of the frequency and pattern of acetaminophen use by alcoholics. To determine these variables, we obtained a detailed ethanol and drug history from patients answering yes to at least one of four questions on the CAGE questionnaire. Patients were classified in terms of their acetaminophen use as nonusers, users as necessary, or regular users. Regular users were further classified as nondaily or daily users, or abusers (>4 g/day). A total of 64 patients were enrolled in the study. The average number of positive responses to the CAGE questionnaire was 3.27 ± 0.91. Of the 64 patients, 34 (53.1%) were continuous daily drinkers, 28 (43.8%) binge drinkers, and 2 (3.1%) had completely discontinued using alcohol. By history, 32 (50)% were nonusers of acetaminophen. Of the 32 users, 12 (37.5%) stated they took it as needed and 20 (62.5%) took it regularly. Of the 20 regular users, 7 (35%) were nondaily users, 11 (55%) were daily users, and 2 (10%) were abusers. Approximately 31% of alcoholics used acetaminophen regularly, most on a daily basis, with 1 of every 10 abusing the drug. Of the 64 alcoholics interviewed, 3 (4.7%) fit the drinking and acetaminophen use patterns theoretically associated with hepatotoxicity.
Pathophysiology and Pharmacotherapy of Common Upper Respiratory Diseases
Authors: Fireman Philip
Published: October 2023

The response of the upper respiratory tract to many environmental factors can be used both to analyze the body's inflammatory process and to choose appropriate therapy. The nose is the major pathway to the lungs, upper airways, sinuses, middle ears, and other parts of the body, and its reactions often represent a major portion of the problem. The most common upper respiratory illnesses are upper respiratory infections (URIs), primarily viral, followed by secondary bacterial infections. Approximately 20% of the total population may manifest allergic rhinitis, which is mediated by immunoglobulin E. This condition is often referred to as hay fever, although there is no direct allergy to hay, and there is no fever. The differential diagnosis includes nonallergic rhinitis with eosinophils, which mimics the pathophysiology of allergic rhinitis but yields negative results on skin testing; vasomotor and hormonal rhinitis; and rhinitis medicamentosa, the rebound congestion associated with overuse of topical adrenergic agents. Therapeutic options include avoiding causative agents, immunotherapy, and pharmacotherapy. Antihistamines produce excellent results in allergic rhinitis when sneezing and itching are present, but are of minimal value as decongestants. The α‐adrenergic agonists are the optimum choices for congestion associated with viral URIs, and allergic or nonallergic rhinitis. Of major importance are accurate diagnosis, selection of appropriate therapy, and patient compliance.
Predictors of Trough Concentrations of Oral Ciprofloxacin
Authors: Paladino Joseph A. , Forrest Alan , Wilton John H.
Published: October 2023

Patients enrolled in a fixed‐dose clinical trial of oral ciprofloxacin had trough concentrations measured to document absorption and monitor compliance. The objective was to determine whether any demographic characteristics might be important predictors of the concentrations. Stepwise multivariate linear regression revealed no correlation between ciprofloxacin trough concentrations and serum creatinine, estimated creatinine clearance (CIcr), weight, height, body surface area, or gender. However, age exhibited a direct linear relationship with trough concentrations (Y in μg/ml), Y = 0.020 · age −0.541 (p<0.003). We conclude that for patients with CIcr 30 ml/minute or above, age is a more important predictor of ciprofloxacin trough concentration than renal function. Dosage adjustment should not be arbitrary but should be guided by minimum inhibitory concentration, clinical response, and side effects.
Neuroleptic Malignant Syndrome Associated With Clozapine Monotherapy
Authors: Thornberg Sheri A. , Ereshefsky Larry
Published: October 2023

Neuroleptic malignant syndrome is thought to be a result of dopamine receptor blockade in the striatum. Clozapine has only weak affinity for dopamine type 1 and 2 receptors, and therefore it was thought this drug would not precipitate the syndrome. However, six cases of the syndrome have been reported in patients receiving clozapine monotherapy. A review of the pathoetiology of symptoms occurring in the syndrome is included.
A Prospective Evaluation of Benzodiazepine Guidelines in the Management of Patients Hospitalized for Alcohol Withdrawal
Authors: Hoey Lori L. , Nahum Avi , Vance‐Bryan Kyle
Published: October 2023

Our institution adopted guidelines for the selection of benzodiazepines to be administered to patients hospitalized for alcohol withdrawal. We assessed the guidelines' impact on prescribing habits, benzodiazepine dosage requirements and costs, and length of intensive care unit (ICU) stay. A 6‐month prospective, observational study was performed in 50 patients who exhibited signs of alcohol withdrawal and received benzodiazepine therapy. Appropriate therapy was defined as lorazepam for patients 60 years and older or those with hepatic dysfunction, and chlordiazepoxide for all other patients. Benzodiazepine costs were calculated based on acquisition cost. Based on our guidelines, 76% of patients were appropriate candidates for a long‐acting agent such as chlordiazepoxide; 61% of these candidates actually received such a drug. Using a benzodiazepine conversion to compare doses in chlordiazepoxide equivalents, there was a significant difference in the total mean dose of chlordiazepoxide (1295.5 mg, SD ± 1571) compared with lorazepam (365.5 mg; SD ± 446) (p<0.01). The mean total chlordiazepoxide acquisition cost was $61.74 (range $0.03–585.98) per patient (28 patients); prior to adoption of the guidelines, the mean cost of benzodiazepine therapy was $1008.72 (± $1554.45). For patients receiving chlordiazepoxide, the mean days of ICU and hospital stay were 1.1 days (range 0–9 days) and 5.6 days (range 1–17 days), respectively; before adoption of the guidelines, the mean number of days of ICU stay was significantly greater (4.1 days, p<0.0001). The guidelines resulted in a substantial change in benzodiazepine prescribing patterns. For the management of patients hospitalized for alcohol withdrawal, chlordiazepoxide can be given safely in higher dosages than previously described, is associated with minimal acquisition costs, and in select patients may facilitate non‐ICU management compared with alternative therapies, and thus result in significant cost savings for the provider institution and third‐party payers.
Effects of Long‐Term Drugs on Alfentanil Clearance in Patients Undergoing Renal Transplantation
Authors: Koehntop Douglas E. , Noormohamed Saleem E. , Fletcher Courtney V.
Published: October 2023

Although patients in renal failure frequently take several drugs on a long‐term basis, drug‐induced alterations in alfentanil metabolism have not been examined as a possible source of variability in alfentanil clearance in this population. We compared the pharmacokinetics of alfentanil during renal transplantation in seven patients receiving and six not receiving long‐term drug therapy. After the rapid intravenous injection of alfentanil 100 μg/kg during isoflurane anesthesia, plasma concentrations were measured at intervals up to 6 hours by radioimmunoassay. The terminal elimination half‐life, steady‐state volume of distribution (Vdss), and total body clearance were determined by non‐compartmental methods. There was no statistical difference in the Vdss between the two patient groups. However, clearance was significantly higher and elimination half‐life lower in the group taking long‐term drugs: clearance 6.94 ± 4.64 versus 3.47 ± 0.16 ml·kg−1·min−1, and elimination half‐life 50.6 ± 13.9 versus 90.7 ± 22.4 minutes, respectively (p<0.05). The higher clearance occurred even though five of the seven patients were taking agents known to be metabolized by the same cytochrome P‐450 hepatic isozyme that metabolizes alfentanil and therefore potential competitive inhibitors of alfentanil metabolism. Drugs taken by the three patients with the highest alfentanil clearances included known inducers of hepatic drug metabolism. Thus, in the presence of several long‐term drugs, the clearance of alfentanil appears to be noticeably increased by inducers of hepatic drug metabolism but unaffected by potential competitive inhibitors.
Interaction of 3′‐Azido‐3′‐Deoxythymidine With the Organic Base Transporter in a Cultured Renal Epithelium
Authors: Bendayan Reina , Georgis Wanda , Rafi‐Tari Shahryar
Published: October 2023

In humans and various animal species, 3′‐azido‐3′‐deoxythymidine (AZT) is in part eliminated by the kidneys, where it undergoes significant tubular secretion. The goal of this project was to develop, in a continuous renal epithelial cell line (LLCPK1), a model of AZT transport in which mechanisms of drug interactions could be investigated. Transport properties of H3‐AZT were studied in LLCPK1 cells grown as monolayers on permeable filters. This system provides access to the basolateral and apical surfaces of the epithelium and allows the determination of substrate transepithelial flux from the basolateral side to the apical side (B → A/secretory direction) and apical to basolateral side (A → B/reabsorptive direction). The B → A flux of AZT was significantly greater than B → A flux of mannitol (a nontransported substrate) and was temperature dependent (37°C > 4°C). The AZT A → B flux was significantly smaller than the B → A flux, indicating that the drug is predominantly secreted in this renal epithelium. The B → A flux was significantly inhibited by the organic bases cimetidine, quinine, quinidine, and trimethoprim. Log concentration dose studies indicate that quinine is a weak inhibitor (IC50 = 9.61 mM) of AZT B → A flux, and that AZT is a moderate inhibitor (IC50 = 0.69 mM) of the organic base cimetidine. These results suggest that AZT may share the organic base transporter in the renal epithelium, and that this model can be used successfully to study transport properties and renal drug‐drug interactions of AZT.