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Abstract Near continuous phase transitions, universal power-law scaling, characterized by critical exponents, emerges. This behavior reflects the singular responses of physical systems to continuous control parameters like temperature or external fields. Universal scaling extends to non-equilibrium dynamics in isolated quantum systems after a quench, where time takes the role of the control parameter. Our research unveils critical scaling in time also during the relaxation dynamics of an open quantum system. Here we experimentally realize such a system by the spin of individual Cesium atoms dissipatively coupled through spin-exchange processes to a bath of ultracold Rubidium atoms. Through a finite-size scaling analysis of the entropy dynamics via numerical simulations, we identify a critical point in time in the thermodynamic limit. This critical point is accompanied by the divergence of a characteristic length, which is described by critical exponents that turn out to be unaffected by system specifics.

The bunker industry has faced negative perception to their trust and credibility in recent times. This is further compounded by the need for the industry to answer new challenges to meet the requirement of the International Maritime Organization 2020. The aim of this work is to illustrate how blockchain technology may be adopted for aiding in bunker dispute resolution.To demonstrate how blockchain may aid in disputes within the bunker industry, this paper first examines the existing bunker supply process, which involves the formation of contracts under English law, the Bunker Delivery Notes, the different types of disputes that may arise during a bunker transaction and the methods of dispute resolution utilised by the industry. Furthermore, the current literature in relation to blockchain technology and blockchain smart contracts is examined. Finally, interviews and surveys within the industry have been conducted to identify the benefits and challenges in adopting blockchain technology.The research found that blockchains may benefit the bunker supply chain offering the effective resolution of bunker quality disputes. Furthermore, blockchains may also serve as a verification tool for electronic bunker delivery notes, which may aid quality and quantity bunker disputes as well as compliance with the new International Maritime Organisation 2020 requirements. As a result, despite the research having shown blockchain to be situationally dependent and having an element of legal uncertainty, blockchain does offer a solution to aid in bunker disputes and for improving the trust and credibility within the bunker industry.

Designing reliable nanoscale quantum-heat engines achieving high efficiency, high power and high stability is of fundamental and practical interest. Here, the authors report the realization of such a quantum machine using individual neutral Cs atoms in an atomic Rb bath, in which quantized heat exchange via inelastic spin-exchange collisions is controlled at the level of single quanta.

Abstract Background Sepsis and septic shock remain drivers for mortality in critically ill patients. The heterogeneity of the syndrome hinders the generation of reproducible numbers on mortality risks. Consequently, mortality rates range from 15 to 56%. We aimed to update and extend the existing knowledge from meta-analyses and estimate 30- and 90-day mortality rates for sepsis and septic shock separately, stratify rates by region and study type and assess mortality rates across different sequential organ failure assessment (SOFA) scores. Methods We performed a systematic review of articles published in PubMed or in the Cochrane Database, between 2009 and 2019 in English language including interventional and observational studies. A meta-analysis of pooled 28/30- and 90-day mortality rated separately for sepsis and septic shock was done using a random-effects model. Time trends were assessed via Joinpoint methodology and for the assessment of mortality rate over different SOFA scores, and linear regression was applied. Results Four thousand five hundred records were identified. After title/abstract screening, 783 articles were assessed in full text for eligibility. Of those, 170 studies were included. Average 30-day septic shock mortality was 34.7% (95% CI 32.6–36.9%), and 90-day septic shock mortality was 38.5% (95% CI 35.4–41.5%). Average 30-day sepsis mortality was 24.4% (95% CI 21.5–27.2%), and 90-day sepsis mortality was 32.2% (95% CI 27.0–37.5%). Estimated mortality rates from RCTs were below prospective and retrospective cohort studies. Rates varied between regions, with 30-day septic shock mortality being 33.7% (95% CI 31.5–35.9) in North America, 32.5% (95% CI 31.7–33.3) in Europe and 26.4% (95% CI 18.1–34.6) in Australia. A statistically significant decrease of 30-day septic shock mortality rate was found between 2009 and 2011, but not after 2011. Per 1-point increase of the average SOFA score, average mortality increased by 1.8–3.3%. Conclusion Trends of lower sepsis and continuous septic shock mortality rates over time and regional disparities indicate a remaining unmet need for improving sepsis management. Further research is needed to investigate how trends in the burden of disease influence mortality rates in sepsis and septic shock at 30- and 90-day mortality over time.

Introduction: Extracorporeal hemoadsorption (HA) is a potential adjunctive therapy in severe cases of COVID-19 associated pneumonia. In this retrospective study we report data from critically ill patients treated with HA during the first and second wave of the pandemic.Patients and Methods: All patients, who received HA therapy with CytoSorb within the first 96 h of intensive care unit (ICU) admission without hospital-acquired bacterial superinfection, were included. Clinical and laboratory data were collected: on admission, before (TB) and after (TA) HA therapy.Results: Out of the 367 COVID-19 cases, 13 patients were treated with CytoSorb, also requiring mechanical ventilation and renal replacement therapy. All patients were alive at the end of HA, but only 3 survived hospital stay. From TB-TA there was a tendency of decreasing norepinephrine requirement: 193.7 [IQR: 34.8–270.4] to 50.2 [6.5–243.5] ug/kg/day and increasing PaO2/FiO2 ratio 127.8 (95% CI: 96.0–159.6) to 155.0 (115.3–194.6) mmHg but they did not reach statistical significance (p = 0.14 and 0.58, respectively). Treatment related adverse events were not reported.Conclusion: The treatment was well-tolerated, and there was a tendency toward an improvement in vasopressor need and oxygenation during the course of HA. These observations render the need for prospective randomized trials.

Heat engines usually operate by exchanging heat with thermal baths at different (positive) temperatures. Nonthermal baths may, however, lead to a significant performance boost. Here, we experimentally analyze the power output of a single-atom quantum Otto engine realized in the quasispin states of individual cesium atoms interacting with an atomic rubidium bath. From measured time-resolved populations of the quasispin state, we determine the dynamics during the cycle of both the effective spin temperature and of the quantum fluctuations of the engine, which we quantify with the help of the Shannon entropy. We find that power is enhanced in the negative-temperature regime and that it reaches its maximum value at half the maximum entropy. Quantitatively, operating our engine at negative effective temperatures increases the power by up to 30% compared to operation at positive temperatures, including the case of infinite temperature. At the same time, entering the negative-temperature regime allows for reducing the entropy to values close to zero, offering highly stable operation at high power output. We further numerically investigate the influence of the size of the Hilbert space on the performance of the quantum engine by varying the number of levels of the working medium. Our work thereby demonstrates control of a multilevel single-atom quantum engine interacting with a realistic atomic bath having many degrees of freedom.

This paper juxtaposes the clinical management of two patients with intracranial hypertension secondary to viral infection: one due to Human Herpesvirus-6 and the second due to Varicella Zoster Virus. Our cases highlight the clinical and scientific importance of cerebrospinal fluid viral polymerase chain reaction testing in the evaluation of the high-pressure headache syndrome. Keywords: Headache, Meningitis, Pseudotumor, Intracranial, Hypertension, CSF, Infection, HHV-6

Objective: To evaluate the cost-effectiveness of bariatric surgery in Italy from a third-party payer perspective over a medium-term (10 years) and a long-term (lifetime) horizon. Methods: A state-transition Markov model was developed, in which patients may experience surgery, post-surgery complications, diabetes mellitus type 2, cardiovascular diseases or die. Transition probabilities, costs, and utilities were obtained from the Italian and international literature. Three types of surgeries were considered: gastric bypass, sleeve gastrectomy, and adjustable gastric banding. A base-case analysis was performed for the population, the characteristics of which were obtained from surgery candidates in Italy. Results: In the base-case analysis, over 10 years, bariatric surgery led to cost increment of EUR 2,661 and generated additional 1.1 quality-adjusted life years (QALYs). Over a lifetime, surgery led to savings of EUR 8,649, additional 0.5 life years and 3.2 QALYs. Bariatric surgery was cost-effective at 10 years with an incremental cost-effectiveness ratio of EUR 2,412/QALY and dominant over conservative management over a lifetime. Conclusion: In a comprehensive decision analytic model, a current mix of surgical methods for bariatric surgery was cost-effective at 10 years and cost-saving over the lifetime of the Italian patient cohort considered in this analysis.

Characterizing and optimizing thermodynamic processes far from equilibrium is a challenge. This is especially true for nanoscopic systems made of a few particles. We here theoretically and experimentally investigate the nonequilibrium dynamics of a gas of a few noninteracting cesium atoms confined in a nonharmonic optical dipole trap and exposed to degenerate Raman sideband cooling pulses. We determine the axial phase-space distribution of the atoms after each Raman cooling pulse by tracing the evolution of the gas with position-resolved fluorescence imaging. We evaluate from it the entropy production and the statistical length between each cooling step. A single Raman pulse leads to a nonequilibrium state that does not thermalize on its own, due to the absence of interparticle collisions. Thermalization may be achieved by combining free phase-space evolution and trains of cooling pulses. We minimize the entropy production to a target thermal state to specify the optimal spacing between a sequence of equally spaced pulses and achieve in this way optimal thermalization. We finally use the statistical length to verify a refined version of the second law of thermodynamics. Altogether, these findings provide a general theoretical and experimental framework to analyze and optimize far-from-equilibrium processes of few-particle systems.

Quantum probes are atomic sized devices mapping information of their environment to quantum-mechanical states. By improving measurements and at the same time minimizing perturbation of the environment, they form a central asset for quantum technologies. We realize spin-based quantum probes by immersing individual Cs atoms into an ultracold Rb bath. Controlling inelastic spin-exchange processes between the probe and bath allows us to map motional and thermal information onto quantum-spin states. We show that the steady-state spin population is well suited for absolute thermometry, reducing temperature measurements to detection of quantum-spin distributions. Moreover, we find that the information gain per inelastic collision can be maximized by accessing the nonequilibrium spin dynamic. Keeping the motional degree of freedom thermalized, individual spin-exchange collisions yield information about the gas quantum by quantum. We find that the sensitivity of this nonequilibrium quantum probing effectively beats the steady-state Cramér-Rao limit by almost an order of magnitude, while reducing the perturbation of the bath to only three quanta of angular momentum. Our work paves the way for local probing of quantum systems at the Heisenberg limit, and moreover, for optimizing measurement strategies via control of nonequilibrium dynamics.

As the use of computer-based science simulations in educational environments grows, so too does the need for research on productive use of simulations. This paper presents ways to create effective assignments that accompany an interactive simulation in a variety of educational environments. A framework that supports the creation of assignments with simulations in any environment is provided, as well as a set of heuristics, or strategies, for how to create assignments based on the particular environment and simulation being used. Case studies of use in college and middle school science classes are provided to illustrate implementation of the heuristics, and how the heuristics can be used to promote productive use of a simulation.

The following case report demonstrates a case of a chronic irreducible patellar dislocation, age‐indeterminate associated with a large medial patellar avulsion fracture that was treated with a vastus medialis obliquus advancement following an extensive lateral release. This case is the only known report of this kind in the literature. The patient is a 41‐year‐old Caucasian female who presented to the clinic with an age‐indeterminate, chronically dislocated patella. She has a past medical history of hypertension and ischemic stroke 1 year prior to presentation, leading to expressive aphasia and lower extremity weakness in addition to patellar instability dating back to age 13. An unsuccessful patellofemoral reduction was performed at an outside clinic, and she was placed in a knee immobilizer and referred to our office. Clinically, the patient had limited knee range of motion with a fixed lateral patellar dislocation that was confirmed on imaging. This case report demonstrates a surgical reduction technique that can be utilized by orthopedic surgeons for chronic patellar dislocations that are not amenable to routine patellar instability surgeries due to the contraction of surrounding soft tissue, chronic bone abnormalities, and position of the chronic dislocation. An extensive lateral release followed by vastus medialis obliquus advancement was performed to center the patella within the trochlear groove and to allow for stable articulation throughout range of motion. The patient was able to regain painless, full range of motion of her knee postoperatively with patellar stability noted on both physical exam and radiographic imaging. [ABSTRACT FROM AUTHOR]

Combined medial and lateral posterior meniscal root tears in the setting of an acute anterior cruciate ligament (ACL) rupture are extremely rare. The following case report demonstrates a high school football player who sustained a noncontact knee injury while performing a spin move at practice. The patient is a 17‐year‐old high school football defensive end who was presented to the clinic 1 week following the injury complaining of persistent knee pain with associated swelling, limited range of motion (ROM), and complaint of instability. During physical examination, the patient was found to have anterior cruciate laxity. Magnetic resonance imaging (MRI) demonstrated a complete midsubstance tear of the ACL and increased signal within the posterior horn of the medial meniscus with no obvious signs of pathology localized to the lateral meniscus. ACL reconstruction (ACLR) was performed and intraoperatively, both medial and lateral root tears were found. A standard bone patellar‐tendon bone (BTB) autograft ACLR was performed with combined medial and lateral root repair utilizing a transtibial pull‐out method for both. The clinical importance is root tears with associated ACL tears can be hard to diagnose on preoperative MRI, especially laterally, so careful assessment of both meniscal roots at the time of arthroscopy is critical. Furthermore, careful creation of the needed root repair tunnels for transtibial repair is critical to avoid coalescence with the ACL tibial tunnel. [ABSTRACT FROM AUTHOR]

Motivational Interviewing, a heavily utilized approach to substance use counseling, has characteristics that make it a culturally sustaining approach to supporting Jewish clients with substance use disorders. The authors address challenges and opportunities in counseling Jewish clients, including identity development and difficulties in addressing mental health and substance use concerns. A case example is provided. [ABSTRACT FROM AUTHOR]