bluuebunny/crossref_metadata_2025 huggingface dataset:
Trouble Shooting the Extracorporeal Membrane Oxygenator Circuit and Patient
Authors: Faulkner Sherry C. , Chipman Carl W. , Baker Lorrie L.
Published: August 2023

Patients requiring extracorporeal membrane oxygenation (ECMO) often become totally dependent on the mechanical life support. The Extracorporeal Life Support Organization (ELSO) reports 2486 incidents of mechanical complications in 5905 ECMO supports. To help decrease the number of mechanical complications, an active quality assurance program was initiated at our institution. This resulted in identification of only 14 incidents of mechanical complications in 100 patients (neonate, pediatric, adult, and cardiac). Techniques for dealing with problems such as loss of roller pump occlusion, changing out of the membrane lung or heat exchanger without interrupting ECMO support, venous air lock, tamponade, emergency transfusion, and other situations were generated into written policies and procedures.

We routinely review and practice problem solving techniques with specific emphasis on monitoring patient hemodyanmics and appearance.

We conclude that written policies and procedures, “water drills,” and continuing education can be beneficial in early recognition, intervention, and/or prevention of ECMO mechanical complications.
The Influence of Heparin-Coated and Uncoated Extracorporeal Circuits on Blood Rheology During Cardiac Surgery
Authors: Belboul Ali , AI-Khaja Najib , Gudmundsson Magnus , Karlsson Hans , Uchino Takashi , Liu Bo , EI-Gatit Abdusalam , Bjell Anders , Roberts Donald , William-Oisson Goran
Published: August 2023

The effect of heparin-coated perfusion circuits on blood trauma during clinical cardiopulmonary bypass (CPB) was studied in order to find out if traumatic changes in the blood could be minimized. Twenty-four patients undergoing coronary artery bypass surgery were randomized prospectively to CPB with heparin-coated circuits (HCC) or non-coated circuits (NCC). The trauma to blood was assessed by measuring damage to blood cells by estimating red and white cell rheology changes. These were measured as red cell filtration rate (RFR) and white cell filtration rate (WFR) using standard microfiltration methods. Furthermore, changes in plasma hemoglobin (P-Hb), whole blood and plasma viscosity were simultaneously assessed. The RFR was significantly reduced in both groups during CPB by 10% in the HCC and 32% in the NCC groups (p<0.01). When comparing the HCC and NCC groups, a significant difference was first seen after 30 minutes ofbypass (p<0.05) and increased at the end ofCPB (p<0.01). Similar results were seen regarding WFR (15% and 36%, p<0.01). After 30 minutes ofbypass, a significant difference was seen between HCC and NCC groups (p<0.05). Furthermore, a significant increase in P-Hb levels were seen during CPB in both patient groups. At the end of CPB, there was a significant difference in P-Hb levels (HCC 305±90 mg/L; NCC 455±78 mg/L, p<0.01) when comparing the two groups.

When comparing HCC and NCC regarding corrected blood viscosity at shear rate 92 s-1, there were significantly higher viscosity values in the NCC group starting at 30 minutes of bypass (p<0.05). Plasma viscosity (PV) at shear rate 583 s-1 , showed similar results (p<0.05).

This study suggests that heparin-coated extracorporeal circuits are less damaging to the rheological properties of blood and would therefore be better suited for clinical use during cardiac surgery using CPB.
Case Study: Use of Two Parallel Oxygenators in a 159 Kilogram Patient during Normothermic Cardiopulmonary Bypass
Authors: Hamilton Carole
Published: August 2023

There have been few reports describing the perfusion of large patients with relevance to oxygen transfer and oxygen consumption (1,2). This report describes the technique of two oxygenators connected in parallel on a 33 year old male who presented to the operating room for repair of an acute dissecting type A ascending aortic aneurysm. The patient's weight was 159 kg, height 189 cm, and BSA 2.88 m2. The calculated blood flow, using a cardiac index of 2.4 L/min/m2 was 6.9 L/min. The theoretical oxygen consumption was calculated as 375 ml/min. The oxygen transfer of the oxygenator is rated at 350 ml/min at a flowrate of 6 L/min. To deal with the possibility of inadequate oxygenation in this large patient, due to insufficient oxygenator surface area, the decision was made to use a second oxygenator in parallel.

The pump was set-up in the usual fashion and the second oxygenator was connected into the existing circuit and de-aired. It was then clamped out of the circuit, ready for future use. Cardiopulmonary bypass was instituted via femoral arterial and right atrial cannulation. Standard normothermic bypass and warm cardioplegia techniques were used after initiation of cardiopulmonary bypass. Venous oxygen saturation indicated insufficient oxygenation within three minutes on pump. The second oxygenator was immediately brought into use resulting in normal physiologic levels within ninety seconds. The patient underwent a successful Cabral procedure, with a total cardiopulmonary bypass time of one hundred and ten minutes. There were no problems separating the patient from bypass.
Extracorporeal Life Support for an Adult with Varicella Pneumonia
Authors: Komorowski Benjamin , Stenach Nina , Furwakawa Satoshi
Published: August 2023

In June of 1992 a 32 year old male presented to the emergency room complaining of dyspnea and a headache. He had been exposed to chickenpox three days prior to his admission. His chest X-ray revealed diffuse bilateral infiltrates. Subsequently, the diagnosis of varicella pneumonia was made and he was started on oxygen and an antibiotic regime of acyclovir and erythromycin. He deteriorated over the next six hours and, in spite of maximal conventional ventilatory support, could not maintain arterial oxygen saturations greater than 80%. He was placed on veno-arterial Extracorporeal Life Support (ECLS) for 69 hours. After being weaned off ECLS, the patient required mechanical ventilation for nine days and was discharged 47 days after admission.
Current Perfusion Techniques for Repair of Giant Cerebral Aneurysms using Deep Hypothermia and Circulatory Arrest
Authors: Mongero Linda B. , Sistino Joseph J. , Beck James , Smith Craig R.
Published: August 2023

Intracerebral aneurysms unapproachable with conventional techniques can be clipped during total circulatory arrest under deep hypothermia. In a series of 30 cases, cardiopulmonary bypass techniques were developed which permit efficient core cooling and rewarming with peripheral (femoral-femoral) cannulation. The perfusion circuit was modified to use the centrifugal pump to apply negative pressure to the venous line without sacrificing the ability to rapidly add and subtract volume, and incorporated protection against air embolism by suction entrainment. Protection of the fibrillating heart during hypothermia was facilitated by transesophageal echo monitoring of the ventricular volume to detect distension. Conversion to central cannulation through median sternotomy was required in three patients (10%) because of inadequate venous return in two patients and severe iliac atherosclerosis in one patient. Early in the series there were two deaths (7%) from aortic dissection. The neurosurgical result, in otherwise inoperable patients, was successful in 90% of the cases.
Potential Risk of Paradoxical Embolization during Use of a Left Ventricular Assist Device: A Case Report
Authors: McCloskey Brian , Eagle Chris
Published: August 2023

A patient undergoing left ventricular assist had a complicated post-operative course due to a patent foramen ovale. This presented as a right to left shunt with desaturation of the arterial blood, and possibly contributed to paradoxical embolization resulting in neurological complications and death. A method is presented to determine the presence of a patent foramen ovale during left ventricular assist. Possible sources of embolization are discussed.
Successful Vaginal Delivery of a Male Infant During Extracorporeal Carbon Dioxide Removal: A Case Report
Authors: Jandhyala Ravi , Haydon Paul , Czaplicka Chet , Claprood Cicie , Casey Kevin
Published: August 2023

Extracorporeal carbon dioxide removal (ECCO2R) has become an effective strategy for the support of newborn infants with severe respiratory failure, but the survival rate for children and adults undergoing this procedure is only 50%. We initiated ECCO2R in a 20 year old, gravida 3, white female who developed severe respiratory distress after seeking treatment for a fever of four days duration and a nonproductive cough. Uterine contractions began shortly after ECCO2R was initiated. Nine hours later a male infant was delivered vaginally. Both mother and baby survived. To our knowledge, ECCO2R had never been used before to support a woman during labor and vaginal delivery.
A Comparison of the Benefits of Roller Pump Versus Constrained Vortex Pump in Adult Open-Heart Operations Utilizing Outcomes Research
Authors: Dickinson Timothy A. , Prichard Jack , Rieckens Faye
Published: August 2023

The purpose of this study was to compare roller pump and centrifugal pump technologies in routine adult open-heart operations to demonstrate the usefulness of applying a proven method of uniform risk stratification (outcomes research). Objective and readily available preoperative patient data was collected retrospectively on 102 non-randomized and consecutive adult openheart operations. Group 1 consisted of 51 adult open-heart operations utilizing a roller pump for arterial blood perfusion. Group 2 consisted of 51 adult open-heart procedures utilizing a constrained vortex pump for arterial blood perfusion. A comparison between the frequency of occurrence of 53 different preoperative risk factors in the roller pump group and the centrifugal pump group found no statistically significant differences (p < 0.05). Outcome data for the roller pump and centrifugal pump groups included such data comparisons as intensive care unit length of stay (LOS), post operative LOS, total LOS, total patient charge, reimbursement, morbidity, and mortality, which revealed no statistically significant differences (p < 0.05). Further comparison studies of roller pumps versus centrifugal pumps for arterial blood perfusion should incorporate this kind of comprehensive data comparison and analysis to reasonably assure that both pump groups are very similar before outcomes research is performed.
Heparin Dose Response in Pediatric Cardiopulmonary Bypass
Authors: Olshove Vincent F. , Langwell James , Burnside Jeff , Bennett Denise
Published: August 2023

Heparin dosing for cardiopulmonary bypass is frequently based on empirical loading doses. Most cite this heparin loading dose as 3 mg/kg (300 units/kg) for both adults and pediatric patients. The purpose of this study was to retrospectively evaluate the heparin dose response (HDR) in a pediatric population.

The HDR of 268 pediatric patients presenting for repair of congenital heart defects at Children's Hospital, Columbus, Ohio, was gathered retrospectively from May 1992 to October 1993. The HDR was gathered for the entire population and divided into four groups based on patient weight: Group I ≤ 5.0 kg; Group II 5.1 to 10.0 kg; Group III 10.1 to 20.0 kg; Group IV > 20 kg.

The HDR is reported as mean (SD, range) in mg/kg. For the entire population (n = 268) the HDR was 3.5 mg/kg (1.20, 1.0 to 7.3). For patients > 20 kg (group IV, n =58) the HDR was 3.0 mg/kg (0.8, 1.0 to 4.9); Group III (10.1 to 20.0 kg, n = 80) HDR was 3.5 mg/kg (1.1, 2.0 to 7.3). Group II (5.1 to 10.0 kg, n = 66) HDR was 3.8 mg/kg (1.2, 1.8 to 7.3). Group I(≤ 5.0 kg, n = 64) HDR was 3.9 mg/kg (1.3, 1.5 to 7.3). Twenty-seven percent of the total population had a HDR > 4.0 mg/kg. When compared by weight, 10% of the patients > 20.0 kg had a HDR > 4.0 mg/kg compared to 45% of the patients < 5.1 kg.

The heparin dose required by children becomes greater as the patient weight (size) decreases with more patients requiring > 400 units/kg. The use of a fixed dose protocol of heparin in the pediatric patient becomes increasingly inadequate as the patient size decreases. Heparin administration in the pediatric patient should be specific to the individual patient with a heparin dose response calculated for each patient.
Prebypass Pheresis and Red Blood Cell Exchange in a Patient with Homozygous SS Sickle Cell Disease Undergoing Cardiopulmonary Bypass: A Case Report
Authors: Parrish James M. , Page Paul A. , Cohen David , Nyreen Mark R. , Kingsley Charles P. , Chronister Tara , Shesol Berry F. , Drew Richard
Published: August 2023

Sickle cell disease was first described by Herrick in 1910. This disease involves an abnormality of the hemoglobin molecule which, under certain conditions, causes the red cell to take on a sickle shape. This abnormal shape and hemoglobin prevent the red cell from performing the normal respiratory functions and interfere with the normal flow through the circulatory system. Individuals demonstrate either a homozygous (dominant) SS or a heterozygous Ss state. Clinical symptoms for patients with SS disease are most often characterized by recurrent painful crises, sequestration of sickled cells, chronic hemolytic anemia, systemic diseases, vasoocclusive crises, permanent organ damage and recurrent infection. These patients usually require exchange transfusions due to the concern that the stress of surgery will precipitate a sickling crisis. Exchange transfusions require large amounts of homologous red blood cells (RBCs) to lower the percentage of the homozygous SS hemoglobin. The use of autologous pheresis in the peri operative period reduces the amount of homologous RBCs required and lowers the patient's exposure to homologous blood and its associated risks. This paper discusses the disease, the planning and the techniques for prebypass pheresis and red cell exchange in a patient with homozygous SS hemoglobin sickle cell disease undergoing cardiopulmonary bypass.
Blick über die Grenze: Was können wir von der Schweiz
lernen?
Authors: Beck Konstantin
Published: August 2023

Das Gesundheitssystem der Schweiz orientiert sich wie Deutschland an Enthovens
Konzept von Managed Competition. Obwohl es grossmehrheitlich von
sozialdemokratischen, wettbewerbskritischen Amtsinhabern geführt worden
ist, zeigen sich besonders dort, wo die Regulierungsdichte gering blieb (bei
Managed Care) und wo wettbewerbsfördernde Regulierung eingeführt
worden sind (beim Risikoausgleich) die gewünschten Effekte. Daneben
bleiben zahlreiche Bereiche, die regulatorisch optimiert werden
könnten.
Patellaosteotomie kombiniert mit modifizierter Trochleaplastik und Tuberositasmedialisierung als Therapie der permanenten Patellaluxation in Beugung
Authors: Dickschas Jörg , Schmeling Arno , Perl Mario , Simon Michael
Published: August 2023

Patellaluxationen in Flexion stellen die schwerste Form der patellofemoralen Dysbalance dar. Sie treten bei jeder Beugung auf, und die meisten bisherigen operativen Therapieversuche zeigten sich frustran. In einem neuen therapeutischen Ansatz wird die konkave Rückfläche der Patella, die auf dem hypoplastischen lateralen Kondylus wie auf Schienen nach lateral gleitet, in den Fokus gerückt. Die operative Therapie besteht aus einer Kombination aus lateral erweiternder Retinakuloplastik, Trochleaplastik, Patellaosteotomie, Tuberositasversetzung und MPFL-Plastik. In dem hier als OP-Video präsentierten Fall konnte bei einer 13-jährigen Patientin mit permanenter Patellaluxation in Beugung auf beiden Seiten ein physiologischer Patellalauf ohne Luxationstendenz bei schmerzfreien Kniegelenken erreicht werden.
Gestaltungsbedarf eines funktionsfähigen Wettbewerbs in der
sozialen Krankenversicherung
Authors: Cassel Dieter , Jacobs Klaus
Published: August 2023

Behandelt werden Funktionsbedingungen wettbewerblicher Steuerung der
Gesundheitsversorgung in einem sozialen Krankenversicherungssystem wie der
gesetzlichen Krankenversicherung (GKV). Eine ihrer konstitutiven Besonderheiten
ist das Solidarprinzip. Danach erhalten Versicherte Leistungen nach dem
medizinischen Bedarf, tragen jedoch zur Finanzierung nach ihrer wirtschaftlichen
Leistungsfähigkeit bei. Das kann mit Wettbewerb konfligieren, der streng
dem Leistungsprinzip folgt. Wie können wettbewerbliche Prozesse im
Krankheitsfall zu hoher Qualität und Wirtschaftlichkeit der Versorgung
beitragen, ohne das Solidarprinzip zu gefährden? Irenische
Lösungen hierfür werden theoretisch-deskriptiv anhand des
Beziehungsgeflechts zwischen dem Versicherungs-, Leistungs- und Behandlungsmarkt
aufgezeigt. Hieraus ergeben sich die Gestaltungserfordernisse für
Selektivverträge, die mehr Wettbewerb zum Wohle der Versicherten und
Patienten in weiten Teilen der GKV ermöglichen würden.
Frequency of serrated polyposis syndrome recognition by community endoscopists
Authors: McWhinney Connor D. , Lahr Rachel E. , Rex Douglas K.
Published: August 2023

Background and study aims Some data indicate serrated polyposis syndrome (SPS) is underdiagnosed. We determined the frequency of SPS diagnosis by community endoscopists prior to referral to a tertiary center.

Patients and methods We performed a retrospective analysis of a
prospectively collected database of SPS patients at a tertiary academic hospital. There were
212 patients who were referred to our center for resection of one or more lesions detected at
a prior colonoscopy and who had records available that allowed determination of whether SPS
was diagnosed before referral.

Results Only 25 of 212 patients (11.8%) had a diagnosis or
suspicion of a polyposis syndrome prior to referral, and only 12 patients (5.7%) had a
specific SPS diagnosis made prior to referral. Among 187 patients diagnosed at our center, 39
had sufficient serrated lesions removed and documented in outside records to meet SPS criteria
prior to referral, but the diagnosis was not made by the referring physician despite adequate
numbers of lesions resected. The remaining cases required lesions removed at our center to
meet SPS diagnostic criteria. Limitations were a single center, single expert
endoscopist.

Conclusions SPS is the most common colorectal polyposis syndrome, but it remains underdiagnosed by community endoscopists. Underdiagnosis may contribute to post-colonoscopy colorectal cancer in patients with SPS.
Green Synthesis of Five-Membered Hetarene N-Oxides: A Designed Approach to the Synthesis of Substituted Chromeno[3,4-c]pyrrole-2-oxides
Authors: Alizadeh Abdolali , Rostampoor Azar , Hasanpour Hamidreza
Published: August 2023

An efficient and chemoselective synthesis of biologically valuable chromeno[3,4-c]pyrrole 2-oxides containing one chiral stereocenter is described. In this method, by using a sequential nucleophilic addition reaction involving coumarins (α,β-unsaturated coumarins or 3-acetylcoumarins), activated acetylenic compounds, triphenylphosphine as a catalyst, and hydroxylammonium chloride (HAC) as an NO source, substituted chromeno[3,4-c]pyrrole 2-oxides were prepared with excellent efficiency. Readily available starting materials, absence of a metal catalyst, green and mild conditions, chemoselectivity, easy purification (the products can be purified by simple filtration and washing with EtOH), and synthetically useful yields are some highlighted advantages of this unprecedented transformation.
Mid-Term Outcomes of Modular Dual Mobility Bearings in Total Hip Arthroplasty
Authors: Arraut Jerry , Ward Spencer , Oakley Christian T. , Schwarzkopf Ran , Macaulay William
Published: August 2023

Modular dual mobility (MDM) prostheses in which a cobalt–chromium liner is inserted into a titanium acetabular shell have the potential for corrosion. This has raised concern. While these constructs have been shown to effectively reduce the risk of dislocation in revision and high-risk primary total hip arthroplasty (THA), previous studies have been limited by the length of follow-up. The purpose of the study is to review the mid-term clinical outcomes of MDM implants with a minimum of 5-year follow-up. A retrospective, observational study was conducted on all consecutive patients who underwent THA with a MDM implant from June 2011 and March 2017 at an urban, tertiary academic medical center. Descriptive statistics were used to describe baseline patient characteristics. Primary endpoints included revision rates, dislocations rates, and implant component survivorship. Implant survival was analyzed using the Kaplan–Meier method. A total of 92 cases (61 primary, 31 revision) underwent THA with a MDM implant at an average follow-up of 6.90 ± 1.48 years (range: 5.01–10.53 years). The mean patient age at the time of surgery was 58.20 ± 11.85 years. Six patients were revised (6.5%, 6/92), two for periprosthetic joint infection (2.2%, 2/92), one due to aseptic loosening (1.1%, 1/92), one due to periprosthetic fracture (1.1%, 1/92), and the remaining two for metallosis (2.2%, 2/92). Kaplan–Meier survivorship analysis showed a 93.5% survival rate for all-cause revisions and 98.9% survival for acetabular component revision. MDM components reliably decrease the risk of dislocation after THA. However, the occurrence of two revisions due to metallosis demonstrates the necessity for continued surveillance in this cohort. Larger trials with long-term follow-up may be required to further elucidate the long-term outcomes and performance of these bearings.
Molecular Genetic Analysis of Mycobacteria, Causing Female Genital Tuberculosis: Possibilities of Sexual Transmission–An Overview
Authors: Chatterjee Sayanti , Kar Sneha , Ghosh Shrayana , Gupta Prabuddha , Santra Pragya , Nan Subhajit , Dutta Abira , Chatterjee Siddhartha , Banerjee Asesh
Published: August 2023

Although tuberculosis (TB) is predominantly known to be a traditional air-borne disease, new modes of transmission have also come to light. While the lungs remain the main entry point, TB can spread to other regions of the body causing extrapulmonary tuberculosis (EPTB). Female genital tuberculosis is one such EPTB that can adversely affect females between the ages of 15 and 45 years and may cause hindrance in their ability of conception and successful pregnancy. Sexual transmission of TB is a lesser-known or poorly investigated route of spread that has recently been confirmed through molecular evidence. Targeted molecular-level studies by polymerase chain reaction (PCR), in addition to interim diagnostic techniques, have offered evidence for the sexual transmission of Mycobacterium subtypes. Recent studies conducted using multiplex PCR on both the male and female counterparts revealed that the male partners had Mycobacterium in their semen, while the female counterparts had it in their endometrium and products of conception resulting in miscarriage. These studies indicate that the mycobacterial infection/infestation in the females may have been brought on by contact with infected male semen. Therefore, it is necessary to identify the genetic loci that are responsible for the sexual transmission of mycobacteria. This can be done by whole-genome sequencing. It has also to be emphasized that screening of sexually active males for genital TB in endemic regions is necessary for the prevention of sexual transmission of mycobacteria.
Multistep Synthesis of Paracetamol in Continuous Flow
Authors: Chen Jian-Li , Hu Jing-Yu , Wang Qi-Fan , Ge Peng , Wang Quan-Hui , Lou Zi-Shuo
Published: August 2023

p-Aminophenol (AP) is the key intermediate of the traditional synthesis of paracetamol. The method of obtaining AP included a selective reduction reaction of the generation of N-arylhydroxylamine (AHA) using nitrobenzene (NB) as the raw material, followed by a Bamberger rearrangement reaction to transfer AHA to the target product. The generation of AHA is a key step, but due to its structural instability and the incompatibility of the two reaction systems, one-pot synthesis of paracetamol faces great challenges. Considering that using flow reactors in series may avoid the problems faced by batch reactors, the article presents the strategy to obtain paracetamol via a continuous flow technology. In particular, we focus on condition screening in total synthesis experiments, including hydrogenation, Bamberger rearrangement, and amidation in flow. The continuous three-step synthesis process used NB as a raw material to generate AHA, which entered the downstream for timely conversion, achieving in situ on-demand preparation of the unstable intermediate AHA, avoiding cumbersome processing and storage processes. Moreover, each step of the reaction system exhibits excellent compatibility, and the work-up is simple.
Engaging Patients and Caregivers to Develop a Patient-Centered Agenda for Comparative Effectiveness Research Focused on the Treatment of Complex Knee Problems
Authors: Royse Lisa A. , Strother Sandi , Trachsel Matt , Mehr David R. , Hoffman Kimberly , Cook James L.
Published: August 2023

Complex articular cartilage loss in the knee is being diagnosed more frequently and earlier in life, and patients are faced with major decisions regarding invasive surgical interventions at increasingly younger ages. There is a critical unmet need to provide patient-centered comparative effectiveness research for the hundreds of thousands of patients faced with these treatment decisions each year. Toward filling the need, we developed the Patient AdvisoR Team iN Orthopaedic ReSearch (PARTNORS) program. We recruited a diverse group of patients and caregivers with lived experiences in dealing with complex knee problems to define patient-centered research priorities for comparative biological and artificial knee surgery research for middle-aged adults. Adapting the Stakeholder Engagement in Question Development and Prioritization Method, PARTNORS defined a 20-question list of patient-centered research questions of factors influencing a patients' choice between biological and artificial knee surgeries. The highest prioritized research question related to functional level postsurgery as it relates to daily activities and recreational activities. The second highest prioritized research questions related to insurance coverage and financial costs. Other prioritized research areas included caregiving needs, implant longevity, recovery and rehabilitation time, patient satisfaction and success rates, individual characteristics, and risks. By engaging a group of patients and caregivers and including them as members of a multidisciplinary research team, comparative effectiveness research that includes patient-centered factors that go beyond typical clinical success indicators for knee surgery can be designed to allow physicians and patients to work together toward evidence-based shared decisions. This shared decision-making process helps to align patients' and health care team's goals and expectations to improve outcomes.
Wirtschaftliche Situation: 300 der 600 größten deutschen Krankenhäuser im Minus
Authors: Doelfs Guntram
Published: August 2023

Mehr als die Hälfte der 600 größten Krankenhäuser in Deutschland schreibt rote Zahlen. Das zeigt eine aktuelle Roland-Berger-Umfrage unter Führungskräften deutscher Krankenhäuser. Von Karl Lauterbachs Klinikreform erwarten diese keine Verbesserung.
Landkreis Cham: „Es passiert etwas“
Authors: Rößing Sabine
Published: August 2023

Im Osten Bayerns ausgerechnet – des Bundeslands also, welches den Krankenhausreformplänen des Bundesgesundheitsministers aktuell den größten Widerstand entgegenbringt – ist etwas gelungen, was in nur wenigen Kommunen gelingt: die Schließung eines Krankenhauses im Austausch für den Aufbau ambulanter Versorgungsangebote. Nur widerwillig trennten sich die Bürger Rodings von ihrer Klinik. Jetzt hoffen die Verantwortlichen, dass der „Gesundheitscampus Roding“ Alternativen aufzeigen kann.
Lichtblick: Therapieansatz mit Wau-Effekt
Authors: Hohnstein Aileen
Published: August 2023

Dieser Artikel ist nur als PDF-Dokument verfügbar.
Expanding and protecting human rights from space
Authors: Bales Kevin
Published: August 2023

The area of surveillance of human activities from above is fraught with concerns and controversy. Such surveillance is clearly being used in ways that invade human lives and often put those lives in danger. At the same time, there is an argument for more oversight, and the need to support more surveillance, in a controlled and monitored way, to expose and render access to sites of criminal activity, and particularly those of the most egregious crimes—slavery, genocide, environmental destruction, and the operation of ‘rebel’ military gangs or national militaries run by rogue states. If nature can be harried, harmed, and turned against human existence, it is also true that humans have now brought increasingly powerful diagnostic techniques to bear so that oceans, land, forests, fields, plains—all ecosystems—can be monitored for health as well as the scars of exploitation—including that of the human within the monitored ecosystem. The field of human rights now stretches far beyond humans to all life and nature—since useful and meaningful human rights can’t truly exist in a physical and natural world that is hostile to homo sapiens. Earth observation can be, and often is, a force for good.
Heterostructure formation of group-III sesquioxides via cation-exchange reactions with metal chloride gases
Authors: Goto Ken , Ueno Tomo , Kumagai Yoshinao
Published: August 2023

Thermodynamic analyses and experimental demonstrations were performed to investigate whether cation-exchange reactions (CERs) with metal chloride gases are a feasible technique for forming heterostructures of group-III sesquioxides. The thermodynamic analyses revealed the possibility of formation of aluminum oxide (Al2O3) layers on gallium oxide (Ga2O3) or indium oxide (In2O3) substrates via CERs with aluminum chloride gases, as well as formation of Ga2O3 layers on In2O3 substrates via CERs with gallium chloride gases, in a practical temperature range. However, CERs with gallium chloride gases or indium chloride gases did not occur on Al2O3 substrates, suggesting that heterostructures were not formed. On the basis of the results of the thermodynamic analyses, a CER was performed by the reaction of n-type β-Ga2O3(2̄01) substrates with aluminum trichloride gas, resulting in the formation of Al2O3 layers. Under optimal conditions, a dense (001)-oriented κ-Al2O3 layer with a thickness of 30 nm was formed and served as an excellent gate oxide in metal–oxide–semiconductor devices. The relative dielectric constant of κ-Al2O3 was obtained via capacitance–voltage measurements, and a high value of ∼22 was obtained in the several tens of kHz band. CERs using metal chloride gases open a new method for forming heterostructures of group-III sesquioxides.
Multifunctional fluorescent nanocomposite of PVDF-TrFE and europium barium titanate
Authors: McGinn Christine K. , Farahmand Nasim , O’Brien Stephen , Kymissis Ioannis
Published: August 2023

Polyvinylidene difluoride trifluoroethylene (PVDF-TrFE) has received widespread application in flexible electronics and biomedical devices but is limited in its sensing modalities to piezoelectricity and pyroelectricity. The addition of optically or magnetically active nanoparticles could provide additional sensing modalities in the same element, which could drive miniaturization of such sensors. Europium barium titanate (EBTO) is one such optically active nanoparticle that could add functionality to such a nanocomposite. In this work, multifunctional nanocomposites of PVDF-TrFE and EBTO are successfully synthesized and characterized for their material and electronic properties. The nanocomposite in this work is the first known multifunctional nanocomposite with PVDF-TrFE and a fluorescent nanoparticle.
Research on the directional characteristics of wind noise emitted by bionic rods
Authors: Zhang Zhe , Chen Tao , Zhang Yingchao , Wang Zhongjian , Zhang Chengchun , Shen Chun , Ren Luquan
Published: August 2023

In this paper, the directional characteristics of wind noise emitted by different bionic rods were studied based on a hybrid computational aeroacoustics method. The noise reduction mechanism of surface grooves, pits, and bumps was analyzed, respectively. The basic principle of noise reduction is to reduce the influence of the vortex shedding on the rod by changing the shape of the rod or passive control technology to reduce the dipole sound source. The unsmooth transverse surface will increase the loss of flow on the leading edge of the rod and reduce the vertical effect of vortex shedding on the rod. The convex leading edge of the rod can help to transfer the vertical noise from low frequency to high frequency and reduce the vertical effect of wake vortex shedding to reduce the peak sound pressure level. The cost of those was the increase in the aerodynamic drag and the increase in noise in the flow direction (the increase in the amplitude of drag fluctuation). In particular, the longitudinal v-groove structure on the surface of the elliptical rod can reduce the circumferential aerodynamic noise while keeping the aerodynamic drag coefficient unchanged.
Observation of hybrid solid solution and superior energy storage in 0.8Ba(Zr0.35Ti0.65)O3-0.2ZnO films
Authors: Zhang Xiaoyu , Pang Zhentao , Ding Wenjuan , Zhou Jinfeng , Jiao Peijie , Xiong Ke , Luo Jin , Deng Yu , Zhang Shan-Tao
Published: August 2023

Unusual substitutional and interstitial solid solutions were observed in (1−x)Ba(Zr0.35Ti0.65)O3-xZnO thin films, where one Zn2+ cation substituted one B-site Zr4+/Ti4+ site and two Zn2+ cations substituted one A-site Ba2+ site simultaneously. Such a hybrid solid solution with an appropriate ZnO content remarkably increases both the electric breakdown strength (Eb) by widening the bandgap and the energy storage efficiency (η) by suppressing the hysteresis of the ferroelectric loop. As a result, the films with x = 0.2 show superior energy storage performance with a recoverable energy storage density (Wrec) of 130.3 J/cm3 and η of 89.1%. This work confirms the feasibility of forming an unconventional hybrid solid solution, which may shed light on further work on perovskite oxides with improved ferroic functionalities.
Gate-tunable superconductivity in hybrid InSb–Pb nanowires
Authors: Chen Yan , van Driel David , Lampadaris Charalampos , Khan Sabbir A. , Alattallah Khalifah , Zeng Lunjie , Olsson Eva , Dvir Tom , Krogstrup Peter , Liu Yu
Published: August 2023

We present a report on hybrid InSb–Pb nanowires that combine high spin–orbit coupling with a high critical field and a large superconducting gap. Material characterization indicates the Pb layer of high crystal quality on the nanowire side facets. Hard induced superconducting gaps and gate-tunable supercurrent are observed in the hybrid nanowires. These results showcase the promising potential of this material combination for a diverse range of applications in hybrid quantum transport devices.
Morphology, size control, and photocatalytic activities of titanium dioxide nanoparticles synthetized by microemulsion method
Authors: Bakhtiari Farhad , Foruhar Nasim , Zelati Amir , Amouamouha Mitra
Published: August 2023

In the present work, we successfully synthesized titanium dioxide nanoparticles (TiO2-NPs) by reverse microemulsion method using cyclohexane, aqueous ammonia materials, and various ratios of surfactants. Using this method, nanoparticles of various morphologies, such as filamentous, sheet, and spherical morphologies, were synthesized. In addition, NPs in very small size (i.e., 4–7 nm for spherical morphology) were obtained. The as-prepared samples showed light absorption in the range of 200–300 nm, indicating their potential application as an UV light induced photocatalyst. The obtained TiO2-NPs were amorphous and can be converted to anatase by heating at 600–750 °C and to rutile by heating above 900 °C. In addition, TiO2-NPs with sheet morphology showed the highest activity on photocatalytic decomposition of methyl orange relative to spherical and filamentous morphologies. We also showed that doping of tin (Sn) atoms in TiO2-NPs causes a significant increase in the photocatalytic activity of NPs and the time needed for photocatalytic decomposition decreases to around one-fifth of the time needed for nondoped NPs. The results of the present research indicated that the microemulsion process is an effective/potential method for the synthesis of some new functional materials.
Iontronic capacitance-enhanced LC wireless passive pressure sensor for high-performance flexible sensing
Authors: Liu Ke , Qin Yuxin , Wu Guirong , Wang Daren , Zhang Haiyan , Wang Weidong , Yuan Yangbo , Gao Libo
Published: August 2023

Wireless passive sensors based on inductor-capacitor (LC) circuits have been an area of intense research in wearable electronics because of their battery-free and wirelessly connected operation. However, significant challenges remain in achieving high sensitivity and long-range performance for such device. In this study, we present a bilayer coils LC wireless passive iontronic pressure sensor (BWIPS) that overcomes these limitations. The bilayer coils strategy enhances the coupling effect and extends the operating distance up to 20 mm. Meanwhile, the capacitive iontronic pressure sensor (IPS) achieves high sensitivity (0.54 kPa−1) and a broad sensing range (400 kPa). By integrating bilayer coils and IPS, the BWIPS exhibits a remarkable sensitivity of −37.4 kHz kPa−1. Furthermore, the flexibility of the sensor allows it to maintain its resonant frequency regardless of various bending radius, making it suitable for use in prosthetic devices. Our BWIPS technology holds great potential for advancing the development of wireless passive sensors in the future, particularly in applications that require high sensitivity, broad sensing range, and non-contact detection at a distance.
Influence of the co- and counter-swirl on combustion instability of the centrally staged combustor
Authors: Ma Jinglong , Hui Xin , Han Meng , Han Xiao , Wang Xinyao , Wang Jianchen , Chi Zixin
Published: August 2023

The centrally staged combustor is an effective way to reduce NOx emissions from combustors. However, combustion instability caused by the mutual coupling between flames and acoustics during the combustion process is almost unavoidable. To better understand this problem, the effect of the swirl rotational direction is investigated in this paper using two different schemes with co-swirl and counter-swirl configurations. Pressure fluctuations and flame dynamics are investigated under self-excited combustion oscillation conditions. The CH* chemiluminescence distribution captured by a high-speed camera is utilized to characterize the flame macrostructure and heat release fluctuations. Furthermore, non-oscillating reaction velocity fields are acquired using particle image velocimetry (PIV) technology. The results indicate that the amplitude and frequency of the counter-swirl scheme are higher than those of the co-swirl scheme at varying main stage equivalence ratios. Combining the results from dynamic mode decomposition and the local Rayleigh index, it is found that the heat release regions of the counter-swirl scheme are mainly concentrated in the shear layer. Higher velocity gradients, vorticities, and strain rates in the inner shear layer (ISL) and outer shear layer (OSL) for the counter-swirl scheme are verified using PIV technology. The driving sources of thermoacoustic oscillations are located in the regions of the ISL, OSL, and the area where the flame impinges on the sidewall of the liner. Additionally, the counter-swirl scheme exhibits larger vorticities and strain rates in the ISL and OSL, facilitating the development of thermoacoustic oscillations.
Laboratory study of instability-driven mixing of fluid mud under surface wave motion
Authors: Aleebrahim Mohammad Ali , Jamali Mirmosadegh
Published: August 2023

Motivated by the role of interfacial instabilities in sediment resuspension in coastal areas, this paper provides quantitative measurements of fluid mud density profile during motion of a surface wave over a muddy bed in a wave flume. Following a fluidization process, a quasi-standing interfacial wave grew owing to a resonant wave interaction with the surface wave. In the process, the quasi-standing wave reached a maximum amplitude and then approached a steady state. The long-time behavior of the resonantly generated interfacial wave and the changes in vertical density profile during wave motion were recorded. Increasing the surface wave frequency led to a higher initial growth rate of the interfacial wave within the experimental range, but the faster growth rate did not result in a larger final amplitude. The results show that excitation of the interfacial wave results in increasing water turbidity such that the water column becomes turbid in a matter of a few minutes. In general, the change in the fluid density profile is highly correlated with the quasi-standing interfacial wave amplitude during the resonant interaction. The amount of entrained mud particles into the clear water by the end of each experiment was determined. The ultimate amplitude of the quasi-standing interfacial wave was found to be a major factor in sediment resuspension.
Electronic-state chaos, intramolecular electronic energy redistribution, and chemical bonding in persisting multidimensional nonadiabatic systems
Authors: Takatsuka Kazuo , Arasaki Yasuki
Published: August 2023

We study the chaotic, huge fluctuation of electronic state, resultant intramolecular energy redistribution, and strong chemical bonding surviving the fluctuation with exceedingly long lifetimes of highly excited boron clusters. Those excited states constitute densely quasi-degenerate state manifolds. The huge fluctuation is induced by persisting multidimensional nonadiabatic transitions among the states in the manifold. We clarify the mechanism of their coexistence and its physical significance. In doing so, we concentrate on two theoretical aspects. One is quantum chaos and energy randomization, which are to be directly extracted from the properties of the total electronic wavefunctions. The present dynamical chaos takes place through frequent transitions from adiabatic states to others, thereby making it very rare for the system to find dissociation channels. This phenomenon leads to the concept of what we call intramolecular nonadiabatic electronic-energy redistribution, which is an electronic-state generaliztion of the notion of intramolecular vibrational energy redistribution. The other aspect is about the peculiar chemical bonding. We investigate it with the energy natural orbitals (ENOs) to see what kind of theoretical structures lie behind the huge fluctuation. The ENO energy levels representing the highly excited states under study appear to have four robust layers. We show that the energy layers responsible for chaotic dynamics and those for chemical bonding are widely separated from each other, and only when an event of what we call “inter-layer crossing” happens to burst can the destruction of these robust energy layers occur, resulting in molecular dissociation. This crossing event happens only rarely because of the large energy gaps between the ENO layers. It is shown that the layers of high energy composed of complex-valued ENOs induce the turbulent flow of electrons and electronic-energy in the cluster. In addition, the random and fast time-oscillations of those high energy ENOs serve as a random force on the nuclear dynamics, which can work to prevent a concentration of high nuclear kinetic energy in the dissociation channels.
Enhancing plane-wave emission with a combination device based on acoustic metamaterial
Authors: Yang Rui , Zhang Xiaodong , Wang Gang
Published: August 2023

Generating high sound-intensity plane waves typically requires transducer arrays with complex synchronizing systems and high-output amplifiers. This work proposes a simple combination device to convert fan-shaped waves into elevated sound-pressure plane waves. The proposed device primarily relies on phase reconstruction of near-zero index metamaterials and the superposition of reflected waves in the reverberation field. The compact device, which is easy to manufacture, consists of a short waveguide equipped with two types of converters. One of the converters makes use of inverted cone's sound-guiding properties to convert fan-shaped waves into cylindrical waves over a broad frequency band. The other converter is comprised of rigid cylinders with triangular lattice arrays, effectively acting as the near-zero index metamaterial to transform cylindrical waves into plane waves. Both the simulated and experimental results show that the emitted plane waves can be linearly amplified by increasing the number of point sources that are separated by integer multiples of the wavelength in the vertical cavity. This study presents a straightforward and efficient approach to generate plane waves with a low-cost array assembly design, thereby enabling the widespread use of acoustic testing and underwater detection.
Hybrid integrated chip-scale laser systems
Authors: Porter C. , Zeng S. , Zhao X. , Zhu L.
Published: August 2023

Photonic integrated circuits (PICs) allow for the rapid advancement of a wide range of optical devices on a compact platform, making them more useful and readily available in the commercial market. Various materials such as III–V semiconductors, silicon, silicon nitride, lithium niobate, and polymers are used to create PICs with certain unique properties. Hybrid integration can combine multiple material platforms via optical coupling and realize multi-functional PICs that overcome the limitations of a single material platform. This allows for a broad application base for hybrid integrated PICs, greatly enhancing their usability and practicality. In this paper, we will discuss the methodology and applications of hybrid integration for chip-scale laser systems, including narrow linewidth, widely tunable external cavity lasers, laser beam combining, integrated frequency combs, and integrated Pockels lasers.
The smallest PbS nanocrystals pervasively show decreased brightness, linked to surface-mediated decay on the average particle
Authors: Hasham Minhal , Green Philippe B. , Rahman Samihat , Villanueva Francisco Yarur , Imperiale Christian J. , Kirshenbaum Maxine J. , Wilson Mark W. B.
Published: August 2023

PbS semiconductor nanocrystals (NCs) have been heavily explored for infrared optoelectronics but can exhibit visible-wavelength quantum-confined optical gaps when sufficiently small (⌀ = 1.8–2.7 nm). However, small PbS NCs traditionally exhibited very broad ensemble absorption linewidths, attributed to poor size-heterogeneity. Here, harnessing recent synthetic advances, we report photophysical measurements on PbS ensembles that span this underexplored size range. We observe that the smallest PbS NCs pervasively exhibit lower brightness and anomalously accelerated photoluminescence decays—relative to the idealized photophysical models that successfully describe larger NCs. We find that effects of residual ensemble size-heterogeneity are insufficient to explain our observations, so we explore plausible processes that are intrinsic to individual nanocrystals. Notably, the anomalous decay kinetics unfold, surprisingly, over hundreds-of-nanosecond timescales. These are poorly matched to effects of direct carrier trapping or fine-structure thermalization but are consistent with non-radiative recombination linked to a dynamic surface. Thus, the progressive enhancement of anomalous decay in the smallest particles supports predictions that the surface plays an outsized role in exciton–phonon coupling. We corroborate this claim by showing that the anomalous decay is significantly remedied by the installation of a rigidifying shell. Intriguingly, our measurements show that the anomalous aspect of these kinetics is insensitive to temperature between T = 298 and 77 K, offering important experimental constraint on possible mechanisms involving structural fluctuations. Thus, our findings identify and map the anomalous photoluminescence kinetics that become pervasive in the smallest PbS NCs and call for targeted experiments and theory to disentangle their origin.