By using Floquet driving protocols and interlacing them with a judicious reservoir emission engineering, we achieve extreme nonreciprocal thermal radiation. We show that the latter is rooted in an ...interplay between a direct radiation process occurring due to temperature bias between two thermal baths and the modulation process that is responsible for pumped radiation heat. Our theoretical results are confirmed via time-domain simulations with photonic and rf circuits.
Electroless Ni deposition has attracted much interest in surface modification of Mg alloy owing to its good performance, especially in corrosion inhibition. In this work, an electroless ...double-layered Ni-B/Ni-P coating on AZ91D Mg alloy was fabricated successfully by plating of a Ni-B layer as primer and a Ni-P layer as outer layer from eco-friendly fluoride-free plating baths. The morphology, composition, and phase structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS), and X-ray diffractometer (XRD), respectively. Several different electrochemical techniques such as linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopies (EIS) were used to analyze the deposition process and demonstrate the enhancement of corrosion inhibition of the Ni-B/Ni-P duplex coating. In addition, compared with Mg alloy and a single Ni-P coating, the new-designed duplex coating also exhibits a remarkable enhancement in micro-hardness.
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•An electroless double-layered Ni-B/Ni-P coating on AZ91D Mg alloy is prepared.•The plating baths for both inner and outer layers are environment-friendly.•The deposition process involves displacement and auto-catalytic reactions.•The coating exhibits a remarkable enhancement in micro-hardness.
Three-dimensional (3D) bioprinting is a promising technique for spatially patterning cells and materials into constructs that mimic native tissues and organs. However, a trade-off exists between ...printability and biological function, where weak materials are typically more suited for 3D cell culture but exhibit poor shape fidelity when printed in air. Recently, a new class of assistive materials has emerged to overcome this limitation and enable fabrication of more complex, biologically relevant geometries, even when using soft materials as bioinks. These materials include support baths, which bioinks are printed into, and sacrificial inks, which are printed themselves and then later removed. Support baths are commonly yield-stress materials that provide physical confinement during the printing process to improve resolution and shape fidelity. Sacrificial inks have primarily been used to create void spaces and pattern perfusable networks, but they can also be combined directly with the bioink to change its mechanical properties for improved printability or increased porosity. Here, we outline the advantages of using such assistive materials in 3D bioprinting, define their material property requirements, and offer case study examples of how these materials are used in practice. Finally, we discuss the remaining challenges and future opportunities in the development of assistive materials that will propel the bioprinting field forward toward creating full-scale, biomimetic tissues and organs.
Staphylococcus aureus is frequently found in patients with atopic dermatitis (AD) and contributes to disease exacerbation. The objective of this study was to evaluate the efficacy and safety of ...bleach baths as an adjunctive treatment in AD patients. Patients between 2 and 30 years old with moderate to severe AD were enrolled in a prospective, randomized, placebo‐controlled study. Patients soaked in diluted bleach or distilled water baths for 10 min, twice a week for 2 months. Efficacy assessments included the Eczema Area and Severity Index (EASI) scores and S. aureus density was determined using quantitative bacterial cultures. Patients in the treatment group showed significant reductions in EASI scores. A 41.9% reduction in S. aureus density from baseline was seen at 1 month further reducing to 53.3% at 2 months. Equal numbers of patients in both groups experienced mild side‐effects. This study demonstrates that diluted bleach baths clinically improved AD in as little as 1 month. No patient withdrew from the treatment arm because of intolerance to the baths.
Haemorrhoids are a common chronic anorectal disease, and haemorrhoidectomy is the standard treatment for advanced (grade III and IV) haemorrhoids. Warm water sitz has commonly been used to stimulate ...urination, cleanse wounds, and decrease pain. Although urinary retention and pain usually occur within the first 24 h after surgery, the warm water sitz bath is provided 24 h after haemorrhoidectomy, which might be a missed opportunity to optimize the quality and efficiency of the care provided.
To investigate the effect of early warm water sitz bath on the day of haemorrhoidectomy surgery on preventing urinary retention and reducing wound pain.
This was a longitudinal double-blind study with a permuted block randomization design.
This study was conducted in a surgical ward of a medical center. An average of 18 patients receiving hemorrhoid surgery in that ward every month.
A total of 64 participants (32 each in the experimental and control groups) were enrolled. (The first recruitment date is January 16, 2020.)
Patients who received haemorrhoidectomy for grade III or IV haemorrhoids from January to December 2020 were enrolled. The experimental and control groups received the same conventional treatment and care before the haemorrhoidectomy. The experimental group started warm-water sitz bath 6 h after the surgery, and the control group started warm water sitz bath on post-haemorrhoidectomy day 1 as usual. Urinary retention was defined as use of Foley catheter during the hospital stay or remaining urine volume ≧ 300 ml using the bladder scan. A numerical rating scale was used to rate the pain level. Each participant was evaluated 6 times in total until hospital discharge. The data were analysed by descriptive statistics, chi-square test, and independent samples t test. Generalized estimating equations and intention to treat were used to identify changes in urinary retention and pain over time and missing data, respectively.
There was no significant difference in the degree of change in the number of people with urinary retention between groups. A change in the wound pain index was noted; the study group had a statistically significant lower pain score than the control group (B = −0.81, 95 % CI: −1.44 to −0.18).
Early warm water sitz bath was a safe and effective strategy to decrease post-haemorrhoidectomy pain, but not urinary retention. Nurses could provide early warm water sitz bath for post-haemorrhoidectomy patients' comfort.
ClinicalTrials.gov ID: NCT04535765
Constant-flux gravity currents of viscoplastic fluid remain axisymmetric when extruded onto a dry horizontal plane. However, if the plane is coated with a shallow layer of water, the current suffers ...a dramatic non-axisymmetric instability in which localized $v$-shaped cuts appear in the outer edge where the viscoplastic fluid is in contact with water. These ‘fractures’ lengthen and guide the subsequent radial outflow, leading to distinctive flower-like patterns. This pattern formation process is illustrated for two viscoplastic materials, an aqueous suspension of Carbopol, and a mixture of water and joint compound (a kaolin-based, commercially available product). The fracturing spreads over the entire upper surface of the current when deeper water baths are used, complicating the extrusion patterns. The instability can be removed entirely when the ambient water layer is replaced by an immiscible liquid of comparable viscosity, indicating that the presence of water at the surface is key to the pattern formation process. We conjecture that the underlying mechanism is the fracture under tension of the viscoplastic material, exacerbated by the ambient water.
The operating process, versatility and the increasing research interest in optimising the process and products technology in the electroless plating method of metal coating, particularly, the ...electroless nickel plating of metallic substrates such as mild steel, necessitates the writing of this review. It is also aimed at providing more literature information, both of the past and the present published research in this field. In this paper, electroless nickel plating is introduced. The various nickel plating solutions and baths’ operating parameters; main types of electroless nickel plating; the mechanism involved in the plating process; application of the nickel plating process to iron powders; advantages and disadvantages and the process’s other applications are reviewed. Electroless nickel plating produces an amorphous deposit in the as-plated condition. The deposit is not dependent on current distribution and hence it is almost uniform in thickness. Electroless nickel plating is far more difficult to remove chemically than conventional nickel deposits due to its superior corrosion resistance. The deposit has a good wettability and is generally hard. However, its bath control is more complex than with electroplating. The bath also has lower efficiency and higher operating costs, even without the use of electricity.
In 2008 a fatal case of primary amoebic meningoencephalitis, due to the amoeboflagellate Naegleria fowleri, occurred in Guadeloupe, French West Indies, after a child swam in a bath fed with ...geothermal water. In order to improve the knowledge on free-living amoebae in this tropical part of France, we investigated on a monthly basis, the presence of Naegleria spp. in the recreational baths, and stream waters which feed them. A total of 73 water samples, 48 sediments and 54 swabs samples were collected from 6 sampling points between June 2011 and July 2012. The water samples were filtered and the filters transferred to non-nutrient agar plates seeded with a heat-killed suspension of Escherichia coli while sediment and swab samples were placed directly on these plates. The plates were incubated at 44°C for the selective isolation of thermophilic Naegleria. To identify the Naegleria isolates the internal transcribed spacers, including the 5.8S rDNA, were amplified by polymerase chain reaction and the sequence of the PCR products was determined. Thermophilic amoebae were present at nearly all collection sites. The pathogenic N. fowleri was the most frequently encountered thermophilic species followed by N. lovaniensis. The concentration of N. fowleri was rather low in most water samples, ranging from 0 to 22 per liter. Sequencing revealed that all N. fowleri isolates belonged to a common Euro-American genotype, the same as detected in the human case in Guadeloupe. These investigations need to be continued in order to counsel the health authorities about prevention measures, because these recreational thermal baths are used daily by local people and tourists.
Bathing is a routine care procedure that exposes preterm infants to prolonged handling, which could cause stress and potentially disrupt infants' biobehavioral responses. The aim of this double-blind ...randomized crossover trial was to compare the preterm infant's body temperature, heart rate (HR), peripheral capillary oxygen saturation (SpO2), salivary cortisol levels, and sleep-wake states during and after swaddled and conventional tub baths. Forty-three infants born at 32 to 36 weeks postmenstrual age, weighing 2225 g or less, were enrolled in the study. Infants were videotaped before and after each type of baths. The time interval between baths ranged from 24 to 72 hours to allow a washout period. Physiological, hormonal, and behavioral responses were collected at baseline and during recovery from baths. No significant differences in the mean body temperature, HR, SpO2, salivary cortisol levels, and sleep-wake states between the bath types were observed in the baseline or recovery responses during the first 20 minutes after bath. Regardless of bath type, salivary cortisol levels showed a nonstatistical significant increase.
We study a quantum interacting spin system subject to an external drive and coupled to a thermal bath of vibrational modes, uncorrelated for different spins, serving as a model for dynamic nuclear ...polarization protocols. We show that even when the many-body eigenstates of the system are ergodic, a sufficiently strong coupling to the bath may effectively localize the spins due to many-body quantum Zeno effect. Our results provide an explanation of the breakdown of the thermal mixing regime experimentally observed above 4-5 K in these protocols.
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