Dark Time Research Articles

Les conspirations d’un romancier historique : Dumas, les sociétés secrètes et la Révolution

It would be very reductive to consider the revolutionary secret societies represented by Dumas as a simple historic seasoning. In his historical novels, in particular the cycle of Mémoires d’un médecin, the Illuminati are a dramatic engine of the narrative, which they structure with consistency; but their main mission is to embody the republican principle that imbues history, until dark times, and to support Providence in its great conspiracy of progress.

A cluster-nanozyme-coenzyme system mimicking natural photosynthesis for CO2 reduction under intermittent light irradiation

Natural photosynthesis utilizes solar energy to convert water and atmospheric CO2 into carbohydrates through all-weather light/dark reactions based on molecule-based enzymes and coenzymes, inspiring extensive development of artificial photosynthesis. However, development of efficient artificial photosynthetic systems free of noble metals, as well as rational integration of functional units into a single system at the molecular level, remain challenging. Here we report an artificial system, the assembly system of Cu6 cluster and cobalt terpyridine complex, that mimics natural photosynthesis through precise integration of nanozyme complexes and ubiquinone (coenzyme Q) on Cu6 clusters. This biomimetic system efficiently reduces CO2 to CO in light reaction, achieving a production rate of 740.7 μmol·g−1·h−1 with high durability for at least 188 hours. Notably, our system realizes the decoupling of light and dark reactions, utilizing the phenol-evolutive coenzyme Q acting as an electron reservoir. By regulating the stabilizer of coenzyme Q, the dark reaction time can be extended up to 8.5 hours, which fully meets the natural day/night cycle requirements. Our findings advance the molecular design of artificial systems that replicate the comprehensive functions of natural photosynthesis.

Multi-qubit gates and Schrödinger cat states in an optical clock.

Many-particle entanglement is a key resource for achieving the fundamental precision limits of a quantum sensor1. Optical atomic clocks2, the current state of the art in frequency precision, are a rapidly emerging area of focus for entanglement-enhanced metrology3-6. Augmenting tweezer-based clocks featuring microscopic control and detection7-10 with the high-fidelity entangling gates developed for atom-array information processing11,12 offers a promising route towards making use of highly entangled quantum states for improved optical clocks. Here we develop and use a family of multi-qubit Rydberg gates to generate Schrödinger cat states of the Greenberger-Horne-Zeilinger (GHZ) type with up to nine optical clock qubits in a programmable atom array. In an atom-laser comparison at sufficiently short dark times, we demonstrate a fractional frequency instability below the standard quantum limit (SQL) using GHZ states of up to four qubits. However, because of their reduced dynamic range, GHZ states of a single size fail to improve the achievable clock precision at the optimal dark time compared with unentangled atoms13. Towards overcoming this hurdle, we simultaneously prepare a cascade of varying-size GHZ states to perform unambiguous phase estimation over an extended interval14-17. These results demonstrate key building blocks for approaching Heisenberg-limited scaling of optical atomic clock precision.

A Novel Algal–Algal Microbial Fuel Cell for Enhanced Chemical Oxygen Demand Removal

To enhance the removal of COD (Chemical Oxygen Demand) by microalgae, this study constructed a novel microalgae–microalgae microbial fuel cell system (AA-MFC). It investigated the coupling relationship between the COD treatment efficiency at the anode and the production of high-value microalgal products at the cathode, as well as explored the effects of different initial inoculum densities and light–dark cycles. The experiment first measured the operational performance of the newly constructed AA-MFC in open-circuit and closed-circuit modes, demonstrating that this novel AA-MFC could start up rapidly within 32 h and operate stably. The results showed that the AA-MFC enhanced the removal of COD and the growth of microalgae biomass at the anode while maintaining stable power generation. When the initial inoculation density of the anode was 1.2 × 108 cell/cm2 and the light–dark cycle time was 18:6 h, the AA-MFC had the most obvious promoting effect on the COD removal of the anode. Compared with normal culture conditions, the COD removal rate increased by 26.0% to 96.1%. These results indicate that the AA-MFC can not only effectively remove pollutants, but also promote the accumulation of high-value microalgae biomass.

Embodied Cognition in Dark Times

Michelle Maiese and Robert Hanna’s The Mind-Body Politic sets out to combine both the philosophy of essentially embodied cognition (EEM) and emancipatory political theory to put forth a “new critique of contemporary social institutions.” There remains, however, an explanatory gap between the general, normative foundations of their approach in EEM, and the particular critiques of neoliberalism and the alternative presented. This paper explores an alternative totalitarian pathway (as understood by Arendt) that such general EEM normativity might lead us, as a friendly invitation for further elaboration on the normative basis of MBP’s critiques of—and proposed alternative to—neoliberal institutions.

EP41 - A Terrorist drone attack: A tragic experience with learning potential

Abstract Introduction A drone strike struck at the Homs Military Academy on October 2023. The strike injured over 277 persons and killed at least 89. One nearby public hospital was the first to receive the first wave of casualties. With a very limited staff and resources, huge efforts were employed to save as many lives as possible even if this meant breaking common protocols. Purpose to remind doctors, especially surgeons that desperate times call for desperate measures and wise judgment is critical in the darkest times. Overview Right after receiving the tragic news of the incident, the hospital declared to give up paperwork, discharge observational admissions, stop non-life-threatening admissions, assign non-clinical staff to assist clinical staff, and call for off-duty workers. As injuries started to present, the hospital prioritized head, thorax, and abdominal injuries. The nurse workforce was assigned to manage the minor injuries while doctors focused on the major ones. While treating and operating on patients, the healthcare providers overlooked sterilization protocols. Due to a shortage of operation rooms, surgical teams have performed operations on some patients in non-operative rooms without monitors, relying solely on IV anaesthesia and portable oxygen cylinders. Some have died, some have suffered from a lifetime disability, yet the prioritizing mentality has saved a lot of lives that day. Conclusion Adhering to protocols is essential. However, many experienced surgeons have come across numerous puzzling situations for which there are no clear standards. We stress the need for a surgeon to take action during these challenging periods and act with their wise judgment.

Poetry, History, Memory: Wang Jingwei and China in Dark Times

Poetry, History, Memory: Wang Jingwei and China in Dark Times

Abstract 41: SerpinA3N in Leptin Receptor Neurons Regulates Metabolic Homeostasis and Cardiovascular Function

Obesity and associated conditions such as type 2 diabetes are among the most concerning health issues in the U.S. Leptin receptor (LepR) signaling in the brain plays a pivotal role in the regulation of food intake and energy expenditure. SerpinA3N is a serine protease inhibitor which is highly expressed in the arcuate nucleus of the hypothalamus, upregulated in diet-induced obesity and by leptin stimulation. However, the role of SerpinA3N in the LepR expressing cells in the control of body weight and glucose homeostasis remain unknown. RNAseq analysis confirmed that SerpinA3N mRNA levels were significantly upregulated in the hypothalamus of mice fed high fat high sucrose diet (HFHSD) for 12 weeks. Using immunofluorescence staining, we confirmed that SerpinA3N is expressed the LepR positive cells of the hypothalamus. Next, we investigated whether loss of SerpinA3N in LepR expressing neurons affects metabolic and glucose homeostasis. For this, we crossed mice harboring floxed alleles of the SerpinA3N gene (SerpinA3N fl/fl ) with mice expressing Cre recombinase driven by the LepR (LepRb Cre ). We found that female, but not male, conditional knockout (CKO, LepRb Cre /SerpinA3N fl/fl ) mice have significantly lower body weight when fed HFHSD. This lower body weight was due to decreased fat mass, measured by NMR. However, no alteration in food intake was observed between female CKO mice and controls, indicating that increased energy expenditure may account for the lower body weight in female CKO mice. Interestingly, CKO mice displayed exaggerated weight loss and anorectic response to leptin treatment (1 mg/g, twice daily, IP), indicating that loss of SerpinA3N enhances leptin sensitivity. Female CKO mice fed normal chow diet also exhibited enhanced insulin sensitivity compared to control animals. On the other hand, male CKO mice displayed significantly improved glucose handling, but no change in insulin sensitivity. Insulin-induced phosphorylation of AKT was elevated only in skeletal muscleof CKO mice relative to controls. Finally, systolic arterial blood pressure of CKO mice fed HFHSD trend to be lower during dark time compared to controls (142±6.4 vs 127.9±7.1 mmHg, p=0.06), although heart rate was not changed. These results demonstrate that SerpinA3N in LepRb-expressing neurons regulate energy and glucose homeostasis in a sex-dependent manner,and may protect from HFHSD induced hypertension.

The Ember Months: A Dark Time for Road Safety in Nigeria?

The Ember Months: A Dark Time for Road Safety in Nigeria?

Thinking in Dark Times: Life, Death, and Social Solidarity

Thinking in Dark Times: Life, Death, and Social Solidarity

Model-based optimisation of microalgae growth under high-intensity and high-frequency pulsed light conditions

High-frequency pulsed light is a promising tool to enhance the performance of microalgae cultivation under artificial illumination. The quantitative comprehension of the effects of pulsed light on cell growth is essential to maximise biomass productivity and to increase the efficiency of artificial light for microalgae growth. In this work, a mathematical model is developed to capture the effect of high-frequency and high-intensity pulsed light in photobioreactors. The model extends the formulation proposed by Zarmi et al. 2020 (https://doi.org/10.1016/j.isci.2020.101115) in order to account for the role of the dark time on photoproduction, photoinhibition effects, and the impact of mixing on cell growth in real photobioreactors. High-frequency pulsed light data from steady state and respirometry experiments are used to calibrate the model, which is demonstrated to shed light on the key photosynthetic mechanisms occurring in these extreme experimental conditions. Furthermore, it is shown how the model can be used to identify optimal operation conditions for microalgae growth, which are confirmed and validated by two respirometry experiments. In particular, it is shown that, for a fixed ratio of the light and dark times, a maximum of productivity can be achieved by minimising the dissipation of photons linked to high light conditions. The result paves the way towards a model-based approach to boost microalgae growth via optimisation of high-frequency high-intensity conditions in artificial light illumination.

Shedding Light on Surgeons' Darkest Times: Coping with Errors and Stress in the Silos of a Silent Surgical Culture.

Shedding Light on Surgeons' Darkest Times: Coping with Errors and Stress in the Silos of a Silent Surgical Culture.

A new hybrid genetic algorithm with tabu search for solving the temporal coverage problem using rotating directional sensors

AbstractOne of the most important problems in directional sensor networks is coverage problem. The coverage can be measured in two ways: positional or temporal. In temporal coverage, the directional sensors rotate periodically round themselves in a repetitive process. Thus, in each time slot, those targets that are positioned within the sensor nodes radius receive their desired coverage. In this model, if a target is left uncovered, it is said that the target has remained in darkness. The main task defined for the temporal coverage model is the minimization of the total dark time for all the targets in the network. This problem has been solved by greedy‐based algorithms in last studies. Greedy‐based algorithms are able to solve the temporal coverage problem in real time. Remember that the performance of greedy algorithms is extremely dependent on the closeness of optimal solution and initial candidates. For this reason, greedy algorithms may obtain local minima due to heuristic search. As far as we know meta‐heuristic algorithms have not been used in past researches to solve such problems. For solving this problem, in this paper two algorithms were developed, GA‐based and hybridized model comprising genetic algorithms and tabu search. A new model was suggested for the chromosome in genetic algorithm. To evaluate the performance of the developed algorithms, they were compared with randomized scenario and greedy‐based algorithm presented in last studies. For better comparison, several parameters, including total dark time, number of sensors, number of targets, sector angle, sensing range were taken into account. The results obtained from the comparison of the algorithms indicated that the developed algorithms are effective in solving the temporal coverage problem in terms of minimizing the total dark time of the targets.

Small things, deep resonance: A sociology for dark times

ABSTRACT Jeffrey C Goldfarb responds to the commentaries and reflections of the authors in this volume.

Systematic approach to measure the performance of microchannel-plate photomultipliers

In this paper, we present our approach to systematically measure numerous performance parameters of microchannel plate photomultiplier tubes. The experimental setups, the analyses and selected results are discussed. Although the techniques used may be different in other locations, the document is intended as a guide for comparable measurements with other types of microchannel plate photomultiplier tubes. Measurements are shown for the following performance parameters: spectral and spatial quantum efficiency, collection efficiency, gain as a function of voltage, position and magnetic field, time resolution, rate capability and lifetime. By using a dedicated 3-axis stepper and an FPGA-based data acquisition system, also inner PMT parameters are measured as a function of the active area, such as relative detection efficiency, dark count rate, time resolution, recoil electron and afterpulse distributions, as well as charge sharing and electronic crosstalk. In addition, some of the parameters are investigated inside a strong magnetic field. For many of these measurements, the change of most setup parameters and the subsequent analysis can be controlled semi-automatically by software scripts.

Women's Love in Antigone by Sophocles and The Tale of Kiều by Nguyễn Du

Abstract Comparative studies have identified “Antigone's sisters” across the globe, excepting for Southeast Asia. Yet in Vietnam, there exists Kiều, the protagonist in Nguyễn Du's The Tale of Kiều, whose cultural significance is comparable to Antigone. What insights can be gained about feminist political power by comparing Antigone to Kiều? Proposing a shift in focus on Kiều and Antigone's love from the questions of who and why to how, the paper argues that their love shares three fundamental commonalities related to their living conditions, actions, and choices. First, they are women who live a life full of love in worlds where love is forbidden. Secondly, they are women who practice love during dark times. And third, they choose to love in unconventional ways, and in doing so, they engender possibilities, particularly in terms of contemplating the interplay between life, death, and freedom. This analysis demonstrates a multiplicity of women's love and the experiences that possess a transcultural dimension, one that signals a type of harmony in the resistance of war through love. Therefore, Antigone and Kiều represent a different direction of a feminist world-building project—that of constructing a world through love.

Enquiries into virulent identifications

ABSTRACT Unquestioned vicious identifications with dubious (e.g. political) figures seem central in today's multiple crises. As in former dark times, when M. Klein described the dynamics triggered by an ‘inner Hitler', the approach offered in this contribution is to explore present forms, which we meet in the consulting room. As will be shown, a crucial step in this process lies in working through those challenges in the countertranserence.

Measurement of Charge State Dynamics in Nitrogen−Vacancy Centers Based on Microwave‐Pulses‐Assisted Longitudinal Relaxations Balancing of Spin Qutrit

AbstractThe nitrogen−vacancy (NV) center in diamond gains its versatility when negatively charged (NV−) but is mediocre when neutrally charged. Particularly, the charge states of NV centers are convertible under optical pumping and during the dark intervals, whose dynamics are mixed with the NV−s’ spin polarizations and relaxations, making them difficult to detect. Here, a microwave‐pulses‐assisted charge state dynamics (CSD) measurement method of NV centers in the dark time (DT) is proposed. The microwave pulses are designed to manipulate the populations of the NV−s’ ground state spin triplets (qutrit) to the equilibrium state before the DT. Thus, the longitudinal relaxations of the qutrit are balanced, and pure CSD can be detected. Interestingly, in an annealed bulk diamond, not only the traditional tunneling‐induced fast exponential CSD are observed, but also a slow and long‐term recharging process, which is probably attributed to the exchanging of the electrons between NV centers and the high‐energy‐level charge traps such as vacancy clusters. Furthermore, results demonstrate a 40% increase in NV−s’ contrast by properly extending the recharging DT. These results are significant for the in‐depth study of the NV centers’ CSD and can improve the sensing abilities of the NV− ensemble.

In situ X-ray and IR probes relevant to Earth science at the Advanced Light Source at Lawrence Berkeley Laboratory

Access to synchrotron X-ray facilities has become an important aspect for many disciplines in experimental Earth science. This is especially important for studies that rely on probing samples in situ under natural conditions different from the ones found at the surface of the Earth. The non-ambient condition Earth science program at the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory, offers a variety of tools utilizing the infra-red and hard X-ray spectrum that allow Earth scientists to probe Earth and environmental materials at variable conditions of pressure, stress, temperature, atmospheric composition, and humidity. These facilities are important tools for the user community in that they offer not only considerable capacity (non-ambient condition diffraction) but also complementary (IR spectroscopy, microtomography), and in some cases unique (Laue microdiffraction) instruments. The availability of the ALS’ in situ probes to the Earth science community grows especially critical during the ongoing dark time of the Advanced Photon Source in Chicago, which massively reduces available in situ synchrotron user time in North America.

Temperature dependence of charge conversion during NV-center relaxometry in nanodiamond

Temperature-dependent nitrogen-vacancy (NV)-center relaxometry is an established tool to characterize paramagnetic molecules near a sensing diamond, gaining momentum in different fields of science. However, recent results indicate that conversion between NV-center charge states impedes these measurements and influences the results for the T1 time. While the temperature dependence of NV centers' T1 time is well studied, additional contributions from temperature-dependent charge conversion during the dark time may further affect the measurement results. We combine temperature-dependent relaxometry and fluorescence spectroscopy at varying laser powers to unravel the temperature dependence of charge conversion in nanodiamond for biologically relevant temperatures. While we observe a decrease of the T1 time with increasing temperatures, charge conversion remains unaffected by the temperature change. These results allow the temperature-dependent performance of T1 relaxometry without further consideration of temperature dependence of charge conversion. Published by the American Physical Society 2024