Life in the Fast Lane: Modeling the Fate of Glass Sponge Larvae in the Gulf Stream

Effective conservation management of deep-sea sponges, including design of appropriate marine protected areas, requires an understanding of the connectivity between populations throughout a species’ distribution. We provide the first consideration of larval connectivity among deep-sea sponge populations along the southeastern coast of North America, illustrate the influence of the Gulf Stream on dispersal, and complement published distribution models by evaluating colonization potential. Connectivity among known populations of the hexactinellid sponge Vazella pourtalesii was simulated using a 3-D biophysical dispersal model throughout its distribution from Florida, United States to Nova Scotia, Canada. We found no exchange with an estimated pelagic larval duration of 2 weeks between populations north and south of Cape Hatteras, North Carolina at surface, mid-water and seabed release depths, irrespective of month of release or application of a horizontal diffusion constant specific to cross-Gulf Stream diffusivity. The population north of Cape Hatteras and south of Cape Cod was isolated. There was some evidence that Gulf Stream eddies formed near Cape Hatteras could travel to the northwest, connecting the populations in the two sub-regions, however that would require a much longer pelagic duration than what is currently known. More likely almost all larval settlement will be in the immediate area of the adults. At sub-regional scales, connectivity was found from the Strait of Florida through to the Blake Plateau, southeastern United States, with the latter area showing potential for recruitment from more than one source population. The influence of the Charleston Bump, a shallow feature rising from the Blake Plateau, was substantial. Particles seeded just north of the Bump were transported greater distances than those seeded to the south, some of which were caught in an associated gyre, promoting retention at the seabed. To the north on the Scotian Shelf, despite weaker currents and greater distances between known occurrences, unidirectional transport was detected from Emerald Basin to the Northeast Channel between Georges and Browns Banks. These major conclusions remained consistent through simulations run with different averaging periods for the currents (decades to daily) and using two ocean model products (BNAM and GLORYS12V1)

Spectropolarimetric variability in the repeating fast radio burst source FRB 20180301A

As the sample size of repeating fast radio bursts (FRBs) has grown, an increasing diversity of phenomenology has emerged. Through long-term multi-epoch studies of repeating FRBs, it is possible to assess which phenomena are common to the population and which are unique to individual sources. We present a multi-epoch monitoring campaign of the repeating FRB source 20180301A using the ultra-wideband low (UWL) receiver observations with Murriyang, the Parkes 64-m radio telescope. The observations covered a wide frequency band spanning approximately 0.7--4 GHz, and yielded the detection of 46 bursts. None of the repeat bursts displayed radio emission in the range of 1.8--4 GHz, while the burst emission peaked at 1.1 GHz. We discover evidence for secular trends in the burst dispersion measure, indicating a decline at a rate of $-2.7\pm0.2\,{\rm pc\,cm^{-3}\,yr^{-1}}$. We also found significant variation in the Faraday rotation measure of the bursts across the follow-up period, including evidence of a sign reversal. While a majority of bursts did not exhibit any polarization, those that did show a decrease in the linear polarization fraction as a function of frequency, consistent with spectral depolarization due to scattering, as observed in other repeating FRB sources. Surprisingly, no significant variation in the polarization position angles was found, which is in contrast with earlier measurements reported for the FRB source. We measure the burst rate and sub-pulse drift rate variation and compare them with the previous results. These novel observations, along with the extreme polarization properties observed in other repeating FRBs, suggest that a sub-sample of FRB progenitors possess highly dynamic magneto-ionic environments.Comment: 21 pages, 14 figures; accepted for publication in MNRA

A single pulse study of PSR J1022+1001

Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), we have recorded 10^5 single pulses from PSR J1022+1001. We studied the polarization properties, their energy distribution and their times of arrival. This is only possible with the high sensitivity available using FAST. There is no indication that PSR~J1022+1001 exhibits giant pulse, nulling or traditional mode changing phenomena. The energy in the leading and trailing components of the integrated profile is shown to be correlated. The degree of both linear and circular polarization increases with the pulse flux density for individual pulses. Our data indicates that pulse jitter leads to an excess noise in the timing residuals of 67 ns when scaled to one hour, which is consistent with Liu et al. (2015). We have unsuccessfully trialled various methods to improve timing precision through the selection of specific single pulses. Our work demonstrates that FAST can detect individual pulses from pulsars that are observed in order to detect and study gravitational waves. This capability enables detailed studies, and parameterisation, of the noise processes that affect the sensitivity of a pulsar timing array.Comment: Accepted by Ap

Atomic magnetometers and their application in industry

In modern detection techniques, high-precision magnetic field detection plays a crucial role. Atomic magnetometers stand out among other devices due to their high sensitivity, large detection range, low power consumption, high sampling rate, continuous gradient measurements, and good confidentiality. Atomic magnetometers have become a hot topic in the field of magnetometry due to their ability to measure not only the total strength of the Earth’s magnetic field, but also its gradients, both slow- and high-velocity transient magnetic fields, both strong and weak. In recent years, researchers have shifted their focus from improving the performance of atomic magnetometers to utilizing their exceptional capabilities for practical applications. The objective of this study is to explore the measurement principle and detection method of atomic magnetometers, and it also examines the technological means and research progress of atomic magnetometers in various industrial fields, including magnetic imaging, material examination, underwater magnetic target detection, and magnetic communication. Additionally, this study discusses the potential applications and future development trends of atomic magnetometers

Case report: Microwave ablation is a safe and effective method for primary hyperparathyroidism in pregnancy

Primary hyperparathyroidism (PHPT) is a rare disease in pregnancy and endangers the health of both pregnant women and fetuses. However, the treatments are very limited for PHPT and most of them are unsatisfactory because of the peculiar state in pregnancy. The only curable method is parathyroidectomy which can be safely performed in the second trimester of pregnancy. In this case, we reported a pregnant woman with primary parathyroid adenoma presenting hypercalcemia and severe vomit at the end of first trimester. Finally, she got cured by microwave ablation at the end of first trimester and gave birth to a healthy baby boy

Progress of Postoperative Adjuvant Chemotherapy in Stage I Non-small Cell Lung Cancer

The morbidity and mortality of lung cancer rank the first place among all the malignant tumor. According to the histopathological characteristics, lung cancer is divided into non-small cell lung cancer (NSCLC) and small cell lung cancer. Only 20% patients diagnosed with NSCLC have the chance for surgery while their 5-yr overall survival is about 30%-60%. The therapeutic outcome of surgery alone is not satisfying. Adjuvant chemotherapy after surgical resection in stage II-IIIa lung cancer showed efficacy in many randomized clinical trials, but its role in stage I disease remains controversial. The choice of appropriate chemotherapy candidates, the selection of chemotherapy regimens and the research progress on biomarker are mainly discussed in this review

Porous graphene nanoarchitectures: An efficient catalyst for low charge-overpotential, long life, and high capacity lithium-oxygen batteries

The electrochemical performance of lithium-oxygen (Li-O) batteries awaits dramatic improvement in the design of porous cathode electrodes with sufficient spaces to accommodate the discharge products and discovery of effective cathode catalysts to promote both oxygen reduction reactions and oxygen evolution reactions. Herein, we report the synthesis of porous graphene with different pore size architectures as cathode catalysts for Li-O batteries. Porous graphene materials exhibited significantly higher discharge capacities than that of nonporous graphene. Furthermore, porous graphene with pore diameter around 250 nm showed the highest discharge capacity among the porous graphene with the small pores (about 60 nm) and large pores (about 400 nm). Moreover, we discovered that addition of ruthenium (Ru) nanocrystals to porous graphene promotes the oxygen evolution reaction. The Ru nanocrystal-decorated porous graphene exhibited an excellent catalytic activity as cathodes in Li-O batteries with a high reversible capacity of 17 700 mA h g, a low charge/discharge overpotential (about 0.355 V), and a long cycle life up to 200 cycles (under the curtaining capacity of 1000 mAh g). The novel porous graphene architecture inspires the development of high-performance Li-O batteries

Graphene supported Sn–Sb@carbon core-shell particles as a superior anode for lithium ion batteries

This paper reports the preparation and Li-storage properties of graphene nanosheets(GNS), GNS supported Sn–Sb@carbon (50–150 nm) and Sn–Sb nanoparticles (5–10 nm). The best cycling performance and excellent high rate capabilities were observed for GNS-supported Sn–Sb@carbon core-shell particles, which exhibited initial capacities of 978, 850 and 668 mAh/g respectively at 0.1C, 2C and 5C (1C=800 mA/g) with good cyclability. Besides the GNS support, the carbon skin around Sn–Sb particles is believed to be a key factor to improve electrochemical properties of Sn–Sb. Keywords: Core-shell nanostructure, Graphene nanosheets, Lithium-ion battery, Sn-S