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The article provides an overview of the formation and experiences of the first naval aviation unit in France during World War I. Comprised of volunteers from diverse backgrounds, the unit was sent to France to boost morale. Trained by French instructors, the men flew alongside allied forces and were eventually stationed at different locations in France. The article also highlights the types of planes used and the training received. After the war, many members of the unit pursued careers in aviation. The text concludes with a tribute to the members of the unit. [Extracted from the article]

Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb1–3. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption. In this work we address this challenge by leveraging advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division4,5. Narrow-linewidth self-injection-locked integrated lasers6,7are stabilized to a miniature Fabry–Pérot cavity8, and the frequency gap between the lasers is divided with an efficient dark soliton frequency comb9. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of −96 dBc Hz−1at 100 Hz offset frequency that decreases to −135 dBc Hz−1at 10 kHz offset—values that are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.

With the rapid advance of machine learning techniques and the increased availability of high-speed computing resources, it has become possible to exploit machine-learning technologies to aid in the design of photonic devices. In this work we use evolutionary optimization algorithms, machine learning techniques, and the drift-diffusion equations to optimize a modified uni-traveling-carrier (MUTC) photodetector for low phase noise at a relatively low bias of 5 V. We compare the particle swarm optimization (PSO), genetic, and surrogate optimization algorithms. We find that PSO yields the solution with the lowest phase noise, with an improvement over a current design of 4.4 dBc/Hz. We then analyze the machine-optimized design to understand the physics behind the phase noise reduction and show that the optimized design removes electrical bottlenecks in the current design.

Today's dental students, Generation Z (Gen Z), are said to learn differently than those of previous generations. As generations of dental students vary, our teaching styles must keep up with unique and changing groups of individuals. This article discusses learner‐focused teaching methods including techniques that address the characteristics of Gen Z learners. Blended learning methods that combine online media with traditional face‐to‐face sessions, team‐based learning, and a flipped classroom format have previously been suggested as ways to increase learning effectiveness and student satisfaction. In this paper, the characteristics and preferences of Gen Z students are described along with the challenges they create with conventional teaching methods. An implementation strategy using principles from organizational agility and Bolman and Deal's Four Frames Model is proposed for dental schools to transition to a more learner‐centered teaching approach. The suggested strategy can be customized and could be useful to schools that wish to enhance their teaching methods to meet the learning needs of Gen Z dental students and beyond.

Pathological hallmarks of Alzheimer’s disease (AD) precede clinical symptoms by years, indicating a period of cognitive resilience before the onset of dementia. Here, we report that activation of cyclic GMP–AMP synthase (cGAS) diminishes cognitive resilience by decreasing the neuronal transcriptional network of myocyte enhancer factor 2c (MEF2C) through type I interferon (IFN-I) signaling. Pathogenic tau activates cGAS and IFN-I responses in microglia, in part mediated by cytosolic leakage of mitochondrial DNA. Genetic ablation of Cgasin mice with tauopathy diminished the microglial IFN-I response, preserved synapse integrity and plasticity and protected against cognitive impairment without affecting the pathogenic tau load. cGAS ablation increased, while activation of IFN-I decreased, the neuronal MEF2C expression network linked to cognitive resilience in AD. Pharmacological inhibition of cGAS in mice with tauopathy enhanced the neuronal MEF2C transcriptional network and restored synaptic integrity, plasticity and memory, supporting the therapeutic potential of targeting the cGAS–IFN–MEF2C axis to improve resilience against AD-related pathological insults.

The fast development of mid-wave infrared photonics has increased the demand for high-performance photodetectors that operate in this spectral range. However, the signal-to-noise ratio, regarded as a primary figure of merit for mid-wave infrared detection, is strongly limited by the high dark current in narrow-bandgap materials. Therefore, conventional mid-wave infrared photodetectors such as HgCdTe require cryogenic temperatures to avoid excessively high dark current. To address this challenge, we report an avalanche photodiode design using photon-trapping structures to enhance the quantum efficiency and minimize the absorber thickness to suppress the dark current. The device exhibits high quantum efficiency and dark current density that is nearly three orders of magnitude lower than that of the state-of-the-art HgCdTe avalanche photodiodes and nearly two orders lower than that of previously reported AlInAsSb avalanche photodiodes that operate at 2 µm. Additionally, the bandwidth of these avalanche photodiodes reaches ~7 GHz, and the gain–bandwidth product is over 200 GHz; both are more than four times those of previously reported 2 µm avalanche photodiodes.

Time window functions are used as broadband excitations to obtain the output power spectrum of photodetectors. Numerical results show a good agreement with experimental results. The proposed method yields a two-orders-of-magnitude reduction in computing time and memory compared to traditional monochromatic calculations. This large reduction makes it possible to design high-performance photodetectors with numerical optimization on desktop computers. We use this approach to design a device whose 3-dB bandwidth is four times larger than the initial design.

An array of Josephson junctions (JJs) was driven with photonically generated current pulses to synthesize a high-fidelity 1 kHz bipolar voltage waveform with a quantum-based amplitude that can be directly related to fundamental constants. A photodiode capable of producing high average photocurrent was used to generate large-amplitude current pulses that were ac-coupled to a JJ array. The resulting bipolar current pulses have enabled the first demonstration of quantum-based bipolar waveform synthesis with an optical drive. We measured the quantum locking range with respect to several operating parameters, including 1.2 mA with respect to a dc bias current applied to the array, confirming the robust synthesis of bipolar waveforms.

Microglia are emerging as key drivers of neurological diseases. However, we lack a systematic understanding of the underlying mechanisms. Here, we present a screening platform to systematically elucidate functional consequences of genetic perturbations in human induced pluripotent stem cell-derived microglia. We developed an efficient 8-day protocol for the generation of microglia-like cells based on the inducible expression of six transcription factors. We established inducible CRISPR interference and activation in this system and conducted three screens targeting the ‘druggable genome’. These screens uncovered genes controlling microglia survival, activation and phagocytosis, including neurodegeneration-associated genes. A screen with single-cell RNA sequencing as the readout revealed that these microglia adopt a spectrum of states mirroring those observed in human brains and identified regulators of these states. A disease-associated state characterized by osteopontin (SPP1) expression was selectively depleted by colony-stimulating factor-1 (CSF1R) inhibition. Thus, our platform can systematically uncover regulators of microglial states, enabling their functional characterization and therapeutic targeting.

Mechanochemical degradation processes such as the fracture of cathode particles play a major role in limiting the service life of advanced lithium-ion batteries (LIBs). In order to help alleviate the degradation of battery performance, it is necessary to measure the relationship between the degradation of the mechanical properties of cathodes and their concomitant degradation of electrochemical performance. In this review, measurements of the mechanical properties of LIB cathode materials are summarized from the literature, along with the range of experimental methods used in their determination. Dimensional changes that accompany charge and discharge are compared for active materials of olivine, spinel, and layered atomic structures. The sensitivity of indentation hardness, Young’s modulus and fracture strength to grain size, porosity, state of charge and charge/discharge history are critically reviewed and discussed with reference to the behavior of conventional, electrically inactive solids. This approach allows for the identification of microstructural properties that dictate the mechanical properties of LIB cathode materials.

Abstract: Chronic myelomonocytic leukemia (CMML) is a relatively rare, heterogeneous syndrome classified as a myelodysplastic syndrome according to the French-American-British classification system. The patient's presenting symptom was a pigmented skin [...]

Transmission of SARS-CoV-2 from humans to other mammals, including pet animals, has been reported. However, with the exception of farmed mink, there is no previous evidence that these infected animals can infect humans, resulting in sustained human-to-human transmission. Following a confirmed SARS-CoV-2 infection of a pet shop worker, animals in the shop and the warehouse supplying it were tested for evidence of SARS-CoV-2 infection.

It is becoming increasingly difficult to find secluded places to anchor for the evening without worry. Stories of anchoring mishaps and strategies for managing a crowded anchorage -- including what type of rode to use, and how to account for water current, keep type, multiple achors, bottom composition, weather patterns and forecasts -- are discussed.

The autopilot can be an important instrument for sailboat enthusiasts because it gives a sailor some rest. It is important to determine the kind of features which are needed or desired. Examples of autopilots are the Oceanpilot, the Cetrek 730, the Autohelm ST6000+ and the AutoNav A-1500., The autopilot can be a mariner's best ally or his worst enemy. It's great for relieving crew stress and fatigue, especially if the crew is shorthanded. However, a skipper must [...]

INTRODUCTION In recent years, powder paint has been introduced in several auto assembly plants for anti-chip, primer, and black out applications, and holds promise for increased future application because of [...]

We report a 6 month-old infant girl with t(1;11)(p32;q23), KMT2A/EPS15-rearranged B-acute lymphoblastic leukemia (B-ALL) that was refractory to traditional ALL-directed chemotherapy. Following administration of blinatumomab, she experienced lineage switch from B-ALL to acute myeloid leukemia (AML). Myeloid-directed chemotherapy resulted in clearance of AML by flow cytometry, though a residual CD19+ B-ALL population persisted (0.14%). Following bridging blinatumomab, the patient achieved B-ALL and AML remission, as measured by flow cytometry. The patient subsequently underwent allogeneic hematopoietic stem cell transplant. Unfortunately, she relapsed with CD19+ B-ALL one-month post-transplantation. Next generation sequencing study of IGH/IGL using ClonoSEQ® analysis detected 3 dominant sequences all present in her original B-ALL, lineage switched AML, and post-transplant relapsed B-ALL, though the latter showed an additional 4 sequences, three of which were present at low abundance in the original diagnostic sample. The presence of the same clones throughout her disease course suggests cellular reprogramming and differentiation following chemotherapy and immunotherapy. This is the first reported case of lineage switch of B-ALL with t(1;11) and also the first report of a lineage switch case that used ClonoSEQ® to define the clonality of the original B-ALL, lineage switched AML, and relapsed B-ALL.

Postpartum plasma exchange appears to be helpful in patients with atypical HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome but only when there is no major deterioration of organ systems. HELLP is a rare complication of preeclampsia in pregnancy. Atypical HELLP occurs when HELLP fails to resolve within a few days after delivery or when it develops after delivery. Between 1984 and 1993, 18 patients with recalcitrant HELLP syndrome were given one or more plasma exchange transfusions when they failed to respond to other therapy. Nine women had multiple complications: infections, immune system or coagulation abnormalities, or damage to the central nervous system, kidneys, heart, or lungs. The nine women who were free of organ damage all responded rapidly to one or two transfusions. By contrast, four women in the group with additional complications failed to respond to transfusion and two women died.

Platelet count may indicate who is likely to have bleeding problems among women with severe preeclampsia who develop the HELLP syndrome. HELLP stands for hemolysis (blood cell destruction), elevated liver enzymes, and low platelet count. However, transfusions do not lower the incidence of postpartum hemorrhage. Records of women with the HELLP syndrome were reviewed, and the women were grouped according to platelet count. There were 132 women with counts less than or equal to 50,000 per microliter and 160 with counts over 50,000 but less than 100,000. Women with platelet counts less than or equal to 40,000 per microliter were significantly more likely to have bleeding complications. Prophylactic blood transfusions did not appear to decrease risk, although it is possible that hemorrhage was reduced in severity. Women with counts over 40,000 were unlikely to have serious bleeding and are thus unlikely to benefit from preventative routine transfusion.

OBJECTIVE--We assessed the relation of diabetes and insulin resistance (IR) on left ventricular (LV) structure and function in African Americans. RESEARCH DESIGN AND METHODS--Among those receiving echocardiograms in cycle 1 [...]

A sample of the business travel market is analyzed to determine whether the importance placed on particular hotel product attributes varies by travel situation. Multiple discriminant analysis is used to see whether certain attributes are able to correctly discriminate among five travel situations.

In 1982, Capasso and co-workers proposed the solid-state analogue of the photomultiplier tube, termed the staircase avalanche photodiode. Through a combination of compositional grading and small applied bias, the conduction band profile is arranged into a series of steps that function similar to the dynodes of a photomultiplier tube, with twofold gain arising at each step via impact ionization. A single-step staircase was previously reported but did not demonstrate gain scaling through cascading multiple steps or report noise properties. Here we demonstrate gain scaling of up to three steps; measurements show the expected 2Nscaling with the number of staircase steps, N. Furthermore, measured noise increased more slowly with gain than for photomultiplier tubes, probably due to the lower stochasticity of impact ionization across well-designed heterojunctions as compared with the secondary electron emission from metals. Excellent agreement was found between the experiments and Monte Carlo simulations for both gain and noise.

Preeclampsia is a syndrome characterized by hypertension, or high blood pressure, protein in the urine, and edema, or the movement of water into the body tissues. In the extreme case of eclampsia, convulsions and coma may result. These syndromes may occur with or without HELLP syndrome, which stands for hemolysis, elevated liver enzymes, and low platelet count (destruction of blood cells, abnormal liver function and diminished clotting factor). In pregnant women, preeclampsia generally resolves spontaneously after delivery. However, in some cases, the condition persists, and may require aggressive intervention. Seven case histories of women with preeclampsia (six) or eclampsia (one) associated with HELLP syndrome, which persisted for more than 72 hours after delivery, indicate the clinical value of plasma exchange. Using an IBM model 2997 Cell Separator, the patient's plasma could be exchanged for fresh frozen plasma while retaining the patient's blood cells. Although each case was unique and required a unique application of the technique, all benefitted, and no serious reactions occurred. It is not clear whether the fresh frozen plasma is providing a factor which is missing from the patient's blood, or whether some toxic substance is being eliminated from the patient's blood by the procedure. Nonetheless, plasma exchange seems to offer great promise for the treatment of preeclampsia-eclampsia with HELLP. (Consumer Summary produced by Reliance Medical Information, Inc.)

Self-steering systems are vital to anybody cruising a long distance short-handed. Windvane gear is the favorite of many, but demands vigilant maintenance.

Advice on safety below deck during a storm is presented. It is important to ensure that there is no breakable glass that could injure crew members, and attention must be given to ensuring a reliable anti-skid surface on the cabin sole.

The instruction of high enrollment general and organic chemistry laboratories at a large public university always has curricular, administrative, and logistical challenges. Herein, we describe how we met these challenges in the transition to remote teaching during the COVID-19 pandemic. We discuss the reasoning behind our approach, the utilization of our existing web-based course content, the additions and alterations to our curriculum, replacement of experimental work with videos, the results of both student and TA surveys, and lessons learned for iterations of these courses in the near future.

Sensitive photodetectors that operate at a wavelength of 2 μm are required for applications in sensing and imaging but state-of-the-art devices are severely limited by high dark current density (Jdark). The narrow-bandgap materials required for mid-infrared (2–5 µm) detection are plagued by carrier recombination and band-to-band tunnelling; as a result, detectors must be operated at cryogenic temperatures. HgCdTe is currently the most commonly used materials system for these applications and has achieved Jdark= 3 × 10−4A cm–2at a gain of 10 while operating at 125 K. Here, we report the details and results for avalanche photodiodes for 2-μm detection based on a separate absorption, charge, and multiplication design in the AlxIn1–xAsySb1–ymaterials system. We achieve comparable Jdarkbetween 200–220 K and demonstrate very low excess noise (k≈ 0.01) and gain >100 at room temperature. Such avalanche photodiodes could prove useful for receivers for eye-safe light imaging, detection and ranging.

•In dyadic relationships, the goals of the high-power partner are privileged over those of the low-power partner.•Higher power reduces attunement and attention to others.•Higher power increases the tendency to objectify and dehumanize others.•Power increases expressions of dominance and aggression, particularly when the level of situational power diverges from expectations or norms.•Greater power limits the detrimental psychological effects of social rejection.

Sex is a key modifier of neurological disease outcomes. Microglia are implicated in neurological diseases and modulated by microRNAs, but it is unknown whether microglial microRNAs have sex-specific influences on disease. We show in mice that microglial microRNA expression differs in males and females and that loss of microRNAs leads to sex-specific changes in the microglial transcriptome and tau pathology. These findings suggest that microglial microRNAs influence tau pathogenesis in a sex-specific manner.

The article discusses the similarities between librarians and fine arts teachers/artists and aims to help librarians build a reciprocal relationship with fine arts programs. Topics include making library collections artist-friendly, managing fine arts inventory, and providing resources for content creation, fostering an alliance between libraries and artists.

Silicon photonics provides a promising platform for energy-efficient interconnects within supercomputers and data centers. However, developing a complementary metal–oxide–semiconductor compatible high-speed photodetector with low dark current has long presented a challenge in the field. In this paper, we report the first O-band InAs quantum dot (QD) waveguide photodiode (PD) heterogeneously integrated on silicon. Record low dark currents as low as 0.01 nA, responsivities of 0.34 A/W at 1310 nm and 0.9 A/W at 1280 nm, and a record high 3 dB bandwidth of 15 GHz was measured. Avalanche gain was observed and a maximum gain of up to 45 and a gain bandwidth product (GBP) of 240 GHz were achieved, which are also record high results for any QD avalanche photodetector (APD) on silicon. Additionally, we demonstrate a device sensitivity of −11  dBm at 10 Gb/s and open-eye diagrams up to 12.5 Gb/s. These QD-based PDs are able to operate as p-i-n PDs or APDs under different bias conditions and offer a promising alternative to heterogeneous InGaAs-on-silicon and SiGe counterparts in low-power optical communication links. They also leverage the same epitaxial layers and processing steps as heterogeneously integrated QD lasers, significantly simplifying the processing and reducing the cost of a fully integrated QD transceiver on silicon.

We demonstrate a III-V avalanche photodiode (APD) grown by heteroepitaxy on silicon. This InGaAs/InAlAs APD exhibits low dark current, gain >20, external quantum efficiency >40%, and similar low excess noise, k∼0.2, as InAlAs APDs on InP.

Heat-induced antigen retrieval (HIAR) is routinely employed on aldehyde-fixed tissue sections to enhance the reactivity of antibodies that exhibit weak or no specific interactions with tissue antigens when applied in conventional immunohistochemical protocols. A major drawback of HIAR protocols is, however, the heat-induced detachment of sections from the microscope slide with resultant impaired tissue morphology or loss of the section. We developed a method in which tissue sections mounted on glass slides are temporally coverslipped, and a clamp is used to compress the sections on the microscope slide during HIAR treatment. This “pressurized coverslipping” during HIAR was tested on various formalin-fixed tissues (murine kidneys and temporal bones, human tonsils and temporal bones) that were embedded in paraffin or celloidin. The method reliably kept the sections adherent to the slide, preserved the tissue morphology, and effectively retrieved tissue antigens for improved results in immunohistochemical labeling, even for exceptionally delicate, large, and poorly adhering sections, that is, decalcified human temporal bone sections. In summary, we present a simple method for improved slide adherence and morphological preservation of tissue sections during HIAR treatment that can be combined with all HIAR protocols and that requires only basic lab equipment.

ABSTRACTUsing the Guangzhou social governance reform pilot as a case, this paper aims to explore the transformation of Chinese governments in managing collaborative non-governmental organisation (NGO) relationships. Local governments have adopted multiple new governance tools, and the expansion of the NGO sector with genuine grassroots development has been observed. However, valuable principles of New Public Management (NPM) paradigm have not been followed, and strong authoritarian and bureaucratic practices have been revealed. The state–NGO relationship has moved from a typical statist to a state-corporatist model. Findings indicate distinctive features of Asian public administration and the limitations of applying Westernized NPM models.