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Adhesion has attracted great interest in science and engineering especially in the field pertaining to nano-science because every form of physical contact is fundamentally a macroscopic observation of interactions between nano-asperities under the adhesion phenomenon. Despite its importance, no practical adhesion prediction model has been developed due to the complexity of examining contact between nano-asperities. Here, we scrutinized the contact phenomenon and developed a contact model, reflecting the physical sequence in which adhesion develops. For the first time ever, our model analyzes the adhesion force and contact properties, such as separation distance, contact location, actual contact area, and the physical deformation of the asperities, between rough surfaces. Through experiments using atomic force microscopy, we demonstrated a low absolute percentage error of 2.8% and 6.55% between the experimental and derived data for Si-Si and Mo-Mo contacts, respectively, and proved the accuracy and practicality of our model in the analysis of the adhesion phenomenon., Competing Interests: The authors declare that they have no competing interests., (This journal is © The Royal Society of Chemistry.)

With the exponential growth of the semiconductor industry, radiation-hardness has become an indispensable property of memory devices. However, implementation of radiation-hardened semiconductor memory devices inevitably requires various radiation-hardening technologies from the layout level to the system level, and such technologies incur a significant energy overhead. Thus, there is a growing demand for emerging memory devices that are energy-efficient and intrinsically radiation-hard. Here, we report a nanoelectromechanical non-volatile memory (NEM-NVM) with an ultra-low energy consumption and radiation-hardness. To achieve an ultra-low operating energy of less than 10 [Formula: see text], we introduce an out-of-plane electrode configuration and electrothermal erase operation. These approaches enable the NEM-NVM to be programmed with an ultra-low energy of 2.83 [Formula: see text]. Furthermore, due to its mechanically operating mechanisms and radiation-robust structural material, the NEM-NVM retains its superb characteristics without radiation-induced degradation such as increased leakage current, threshold voltage shift, and unintended bit-flip even after 1 Mrad irradiation., (© 2023. The Author(s).)

The charge of microbubbles in water is considered to be negative at the liquid-bubble interface. We investigated, for the first time, the charge of a single bubble sonoluminescence (SBSL bubble) that exhibits spatiotemporally stable light emission. When negative DC voltage was applied, the SBSL bubble was attracted to a hot electrode. Conversely, the SBSL bubble was repelled by the hot electrode when positive DC voltage was applied. The translation of the SBSL bubble under an electric field suggests that it is positively charged, and the bubble moved to an equilibrium position to balance the primary Bjerknes force and the electrostatic force. The amount of bubble translation under an electric field depended on the elapsed time of sonoluminescence, suggesting that the products generated inside the SBSL bubble affect the mechanism of bubble charging. Furthermore, we measured the electric field effects on bubble expansion and contraction by a light scattering technique. Applying a positive voltage decreased the maximum bubble diameter and also the intensity of the SBSL. Conversely, applying a negative voltage increased the maximum bubble diameter and also the intensity of the SBSL. The present study revealed that a SBSL bubble is positively charged.

Background: Spontaneous isolated posterior inferior cerebellar artery (PICA) dissection has been reported more frequently since high-resolution vessel wall magnetic resonance imaging (HR vw-MRI) was introduced to the field. The intimal flap or double lumen, which is commonly reported to be a direct sign of the dissection, is not easily detectable on HR vw-MRI because the size of the PICA is very small and tortuous., Case Presentation: Two patients with posterior circulation ischemic stroke due to spontaneous isolated PICA dissection underwent HR vw-MRI. The curved multiplanar reconstruction image reconstructed using three-dimensional (3D) HR vw-MRI (3D curved MPR imaging) is helpful to observe tortuous blood vessels such as the PICA because it can visualize the entire vessel course in a single plane. In this report, routine HR vw-MRI revealed only an intramural hematoma in both patients. However, 3D curved MPR imaging discovered the intimal flap which was not observed on the routine HR vw-MRI. Therefore, these two patients were diagnosed with spontaneous isolated PICA dissection due to the intimal flap that was observed on the 3D curved MPR image., Conclusion: HR vw-MRI is useful for the early diagnosis of isolated PICA dissection. Furthermore, we believe that 3D curved MPR imaging could improve the possibility of diagnosing the dissection early because it can easily confirm direct signs such as an intimal flap or double lumen.

Purpose: Unruptured intracranial aneurysm commonly occurs in the older people. Because the rupture risk increases with age, the factors associated with aneurysms might be different according to age. We aimed to evaluate unruptured intracranial aneurysm characteristics in healthy, symptom-free older patients., Methods: Patients who visited the health examination center of two regional university hospitals and underwent computed tomography angiography between March 2001 and March 2017 were included. The putative aneurysm risk factors were identified; the aneurysm size and shape were determined by CT angiography, and measuring the ASPECT and dome/neck ratios. All images were interpreted independently by a neurosurgeon and a neurologist for improving size measurement accuracy., Results: The unruptured intracranial aneurysm prevalence was 2.23% and 2.75% in the patients aged ≤ 60 and > 60 years, respectively. Among the younger group, female sex [odds ratio (OR), 1.85; P = 0.002], age (OR, 1.05; P < 0.001), hypertension (OR, 1.88; P < 0.001), coronary artery disease (OR, 0.26; P < 0.001), smoking (OR, 2.04; P < 0.001), and stroke family history (OR, 1.36; P = 0.047) were independently associated with aneurysm; anterior communicating artery aneurysms were the largest. Among the older group, female sex (OR, 1.76; P = 0.005), hypertension (OR, 2.54; P < 0.001), coronary artery disease (OR, 0.27; P < 0.001), and stroke family history (OR, 1.94; P = 0.003) were independently associated with aneurysm; internal carotid artery aneurysms were the largest., Conclusions: The factors related to unruptured intracranial aneurysm formation varied by age, and coronary artery disease protected against aneurysm formation regardless of age. The factors affecting unruptured intracranial aneurysm formation are different according to age and aneurysm location.

The article Asymptomatic unruptured intracranial aneurysms in the older people, written by Sang Woo Ha, Pahn Kyu Choi, Ji Eun Oh, Jung Soo Park and Hyun Goo Kang was originally published electronically on the publisher's internet portal (currently SpringerLink) on 29 October 2018 without open access.

The nutrition support team is a multidisciplinary team composed of medical doctors, registered nurses, pharmacists, and nutritionists, who evaluate the nutritional status of patients. The objective of this study was to determine the relationship between indications for nutrition support team therapy and the nutritional status of patients hospitalized in local major hospitals.Patients who were referred to a nutrition support team from January to December 2016 were enrolled. Patients were classified into 4 age groups, and the weight categories were determined using body mass index (BMI). Four of 6 indications were used for referral to a nutrition support team. The required calories were estimated, and the nutritional status was classified into malnutrition or eutrophia, based on the estimation.The proportion of elderly patients (37.0%) was higher than that of younger ones (28.3%). Patients with higher BMI had a relatively lower proportion of malnutrition. Patients receiving enteral nutrition had greater risk of malnutrition (adjusted odds ratio [aOR] = 3.77, 95% confidence interval [CI] = 2.71-5.24). Patients receiving parenteral nutrition (aOR = 0.38, 95% CI = 0.30-0.47) and treated in the intensive care unit (aOR = 0.70, 95% CI = 0.54-0.91) had lower risk of malnutrition. Patients with >3 indications for nutrition support team therapy had a lower risk of malnutrition than those with only 1 indication (aOR = 0.54, 95% CI = 0.37-0.77).Parenteral nutrition was the most common indication for referral to nutrition support team therapy; however, enteral nutrition had the poorest nutritional status. Patients receiving enteral nutrition who are referred to a nutrition support team need an intensive nutrition support strategy.

Rationale: Cerebral microbleeds are lesions that appear as round low signal intensity areas with a diameter of 2-5 mm on gradient echo T2-weighted sequence magnetic resonance imaging. Cerebral microblees are hemorrhages found in the brain parenchyma and they are caused by the extravasation of the blood. Although more patients with ischemic stroke are found to have cerebral microbleeds, only a few studies have evaluated other neurologic abnormalities outside of cognitive dysfunction due to cerebral microbleeds., Patient Concerns: A 73-year-old female patient had only a lacunar infarction with the development of a new microbleed whenever a new neurologic symptom occurred, without the occurrence of acute ischemic stroke., Diagnoses: A 73-year-old female patient diagnosed symptomatic cerebral microbleeds., Interventions: Brain magnetic resonance imaging was taken within a few hours of the occurrence of a new symptom and we confirmed increased cerebral microbleeds in the ventral-posterolateral area of the thalamus, consistent with the symptoms., Outcomes: This case study is meaningful because it proves that repeated occurrences of cerebral microbleeds in a specific area can induce acute ischemic stroke-like symptoms., Lessons: Cerebral microbleeds have been considered to be asymptomatic lesions thus far. However, recent studies have reported the association of cerebral microbleeds with neurological symptoms including cognitive dysfunction. This study confirmed the presence of newly formed cerebral microbleeds through imaging follow-ups whenever a symptom occurred.

Orange emission was observed during multibubble sonoluminescence at 1 MHz in water saturated with noble gas. The emission arose in the vicinity of the peeled ground electrode of a piezoceramic transducer exposed to water, suggesting that cavitation bubbles were affected by the electric fields that leaked from the transducer. The spectrum of the emission exhibited a broad component whose intensity increased towards the near-infrared region with peaks at 713 and 813 nm. The spectral shape was independent of the saturation gas of He, Ne, or Kr. The broad component was attributed to the superposition of lines due to vibration-rotation transitions of water molecules, each of which was broadened by the high pressure and electric fields at bubble collapse. An emission mechanism based on charge induction by electric fields and the charged droplet model is proposed., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Na emission in single-bubble sonoluminescence (SBSL) was observed from 0.1mM sodium dodecyl sulfate (SDS) solution containing a dissolved noble gas at a low acoustic pressure, at which a continuous spectral component was negligible. High-speed shadowgraph movies were captured at a frame rate of 30,000fps, which indicated that bubble dancing is responsible for the Na emission. The measured bubble path length was well correlated with the Na intensity. The disintegration of a daughter bubble followed by immediate coalescence was frequently observed, which may have been the cause of the bubble dancing. A comparison of the Na spectra obtained in SBSL and multibubble SL showed that the conditions under which Na emission is generated are twofold. A narrow component was observed in the Na spectrum in SBSL, while narrow and broad components were observed in MBSL., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Sonoluminescence from sodium dodecyl sulfate (SDS) aqueous solutions exhibits Na emission. The spectrum of Na emission was measured as a function of sonication time for a total of 30 min at an ultrasonic frequency of 148 kHz. The spectral line profiles changed with the sonication time, suggesting that the Na emission consists of two components: broadened lines, which are shifted from the original D lines, and unshifted narrow lines. The intensity of the unshifted narrow lines decreased at a greater rate than that of the broadened lines with increasing sonication time. This effect was enhanced at a higher acoustic power. The shifted broadened lines remained after sonication for 30 min. We propose that these quenching effects are caused by the accumulation of gases decomposed from SDS molecules inside bubbles. The CO₂ gas dependence of Na emission in NaCl aqueous solutions showed a similar change in the line profiles to that in SDS aqueous solutions, which supported this proposition. The unshifted narrow lines are easily affected by foreign gases. The results suggest that the two components originate from different environments around the emitting species, although both of them originate from the gas phase inside bubbles. The generation mechanisms of the two components are discussed., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The decreasing effect of sonoluminescence (SL) in water at high acoustic powers was investigated in relation to bubble dynamics and acoustic emission spectra. The intensity of SL was measured in the power range of 1-18W at 83.8kHz for open-end (free liquid surface and film-covered surface) and fixed-end boundaries of sound fields. The power dependence of the SL intensity showed a maximum and then decrease to zero for all the boundaries. Similar results were obtained for sonochemiluminescence in luminol solution. The power dependence of the SL intensity was strongly correlated with the bubble dynamics captured by high-speed photography at 64kfps. In the low-power range where the SL intensity increases, bubble streamers were observed and the population of streaming bubbles increased with the power. At powers after SL maximum occurred, bubble clusters came into existence. Upon complete SL reduction, only bubble clusters were observed. The subharmonic in the acoustic emission spectra increased markedly in the region where bubble clusters were observed. Nonspherical oscillations of clustering bubbles may make a major contribution to the subharmonic., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Multibubble-sonoluminescence spectra from Ar-saturated KCl aqueous solutions were measured in the temperature range of 15-40 °C at frequencies of 48 kHz, 148 kHz, and 1 MHz. The effects of dissolved rare gases and the ultrasonic frequency on the shape of the K atom emission spectrum were examined. The line width of the K doublet was independent of the solution temperature, whereas the K line intensity decreased with increasing temperature. The spectra from Xe- and Ar-saturated solutions at 148 kHz exhibited a red-shifted and asymmetrically broadened doublet of K lines. The spectrum from a He-saturated solution, on the other hand, exhibited symmetrically broadened K lines, which were slightly blue-shifted. The observed effects of rare gases are in good agreement with those obtained by gas-phase spectroscopy. These results strongly indicate that the excited K atoms are perturbed by rare gases inside bubbles. The spectra from Xe- and Ar-saturated solutions also indicated that the K doublet is composed of two types of peaks, shifted broadened lines and unshifted narrow lines. These two types of peaks were clearly separated at a frequency of 48 kHz with a high acoustic power in the case of Ar-saturated solutions. The intensity of the broadened lines relative to that of the narrow lines markedly decreased at 1 MHz. Although the narrow lines as well as the broadened lines may have originated from inside the bubbles, the exact mechanism is still unclear.

Multibubble sonoluminescence pulses of Na and continuum emissions were measured from NaCl-ethylene glycol solution saturated with Xe at 28 kHz. The Na emission consisted of multiple-peak pulses and single pulses. The intrinsic pulse width estimated from single pulses was 0.37 ns, which differs from 10-165 ns obtained by previous work. High-speed shadowgraphs of bubble dynamics and high-speed movies (32000 fps) of sonoluminescence were observed. The observations suggest that the multiple-peak pulse is due to the superposition of single peaks resulting from bubbles fragmented from a characteristic bubble which repeats the fragmentation and coalescence. This phenomenon may be specific to viscous liquids.

Sonoluminescence spectra from argon-saturated NaCl solution were measured in the concentration range of 0.5-4 M at the frequency of 138 kHz. The line broadening of sodium atom emission was observed at various acoustic powers in the range from 1.8 to 16.2 W. The sodium D line showed a maximum intensity at a NaCl concentration of 2 M, which corresponded to the maximum production of OH radicals estimated by KI dosimetry. The effects of the addition of a small amount of ethanol on the line width and intensity were closely investigated at various acoustic powers. The sodium line width increases with ethanol concentration and also with power, whereas the line intensity is strongly quenched with increasing ethanol concentration. The results conclusively show that the sodium emission occurs in the gas phase within bubbles. The line broadening is due to interactions with high-pressure argon, and the maximum relative density of gas at bubble collapse was estimated to be 59.5 from the comparison with spectroscopic data. Further line broadening and quenching upon the addition of ethanol arise from collisions with gaseous products obtained from the decomposition of ethanol. The mechanism of sodium excitation is inferred to be as follows. Sodium ions enter bubbles as droplets, and salts are formed because of the high temperature within bubbles. Sodium atoms are generated by the dissociation of salts and then undergo electronic excitation by OH and H radicals.

Spectra of multi-bubble sonoluminescence (MBSL) were measured in argon-saturated water and ethanol solutions in the concentration range 2-100 mM at the frequencies of 116 kHz and 1.0 MHz. The spectral peaks from OH-radical emission near 310 nm were observed at relatively low ultrasonic power at both frequencies. The sub-peaks at 290 and 340 nm were also observed, which are attributed to OH-radical vibronic transition. The MBSL spectra from ethanol solutions indicated that the quenching of OH-radical emission was more efficient than that of underlying continuous spectrum. The continuous spectrum suggested the decrease in temperature with increasing ethanol concentration. The concentration dependence of spectrum quenching showed no frequency dependence. A new peak was observed at 385 nm only at small ethanol concentrations and at the frequency of 1.0 MHz, which attributed to CH or CN molecule emission.

We analyzed a unique rice (Oryza sativa L.) blast lesion mimic (blm) mutant for differentially expressed proteins in leaves of one- and two-week-old seedlings manifesting the lesion mimic phenotype. Gel-based one- and two-dimensional electrophoresis (1- and 2-DGE) was performed using leaves (blm and wild-type, WT) before (stage 1, S1) and after (stage 2, S2) lesion formation. 1-DGE immunoblotting revealed potent increase in the expression of a key pathogenesis-related (PR) marker biosynthetic enzyme, naringenin 7-O-methyltransferase, involved in rice phytoalexin sakuranetin biosynthesis, and three oxidative-stress-related marker proteins, catalase, ascorbate peroxidase (APX), and superoxide dismutase (SOD) in leaves of the blm mutant. 2-D gel immunoblotting analysis with anti-APX and anti-SOD antibodies revealed newly appearing cross-reacting protein spots in blm. 2-DGE analysis detected 50 Coomassie brilliant blue-stained protein spots differentially expressed in blm. A total of 23 and 44 protein spots was excised for analysis by N-terminal amino acid sequencing and nano-electrospray ionization liquid chromatography mass spectrometry, respectively; 26 nonredundant proteins were identified. The pathogenesis-related class 5 and 10 proteins, including a new OsPR10d protein, were significantly induced in blm. The OsPR5 protein spot was stained with Pro-Q Diamond phosphoprotein gel stain suggesting OsPR5 to be a putative phosphoprotein. Surprisingly, protein spot 20, a leaf OsPR10b, showed identity to a rice root-specific PR-10 (RSOsPR10). To resolve this discrepancy, we checked its expression in leaves of blm and WT (S1 and S2), respectively, using gene-specific primers and reverse transcriptase-polymerase chain reaction; RSOsPR10 mRNA was found to express in the leaves.

To promote dopamine cell survival in human fetal tissue strands transplanted into immunosuppressed 6-OHDA-lesioned rats, we have preincubated tissue in insulin-like growth factor-I (IGF-I, 150 ng/ml) and basic fibroblast growth factor (bFGF, 15 ng/ml) in vitro for 2 weeks. Growth factor treatment did not affect the rate of homovanillic acid production in vitro but increased overall dopamine neuron survival in animals after transplant from 1240 +/- 250 to 2380 +/- 440 neurons (P < 0.05). Animals in the growth factor-treated group had a significantly greater reduction in methamphetamine-induced rotation (66%) compared to control transplants (30%, P < 0.05). We conclude that in vitro preincubation of human fetal tissue strands with IGF-I and bFGF improves dopamine cell survival and the behavioral outcome of transplants., (Copyright 2001 Academic Press.)

Extracts from skeletal muscle cell cultures have been shown to increase levels of the enzyme tyrosine hydroxylase (TH) and promote survival of different types of developing neurons in vitro. To determine the effect of muscle cell co-grafts on the survival of dopamine neurons in a rat model of Parkinson's disease, we transplanted an embryonic day (ED)-15 rat mesencephalic cell suspension alone or with neonatal muscle cells into 6-hydroxydopamine (6-OHDA) denervated rat striatum. In parallel experiments conducted in vitro, we cultured ED-15 rat mesencephalon or rat striatum in conditioned medium from neonatal rat muscle cultures (MC-CM). Our results showed that: (A) in vitro, MC-CM increased the number of TH-immunoreactive (TH-IR) neurons in embryonic mesencephalic cultures but did not induce expression of TH in embryonic striatal cultures; (B) in vivo, animals with co-grafts of muscle cells and ED-15 mesencephalon had more TH-IR in the grafted striatum compared to animals that received mesencephalic cells grafts alone, although the graft-induced reversal of circling behavior in response to methamphetamine was the same in both transplanted groups; and (C) grafts of muscle cells alone did not induce TH-IR in the denervated striatum and did not reduce methamphetamine-induced circling. These findings suggest that in vivo, neonatal muscle cells secrete factors that promote survival and/or outgrowth of fetal midbrain dopamine cells and improve the levels of TH-IR in grafted striatum.

Parkinson's disease symptoms can be improved by transplanting fetal dopamine cells into the putamen of parkinsonian patients. Because the supply of human donor tissue is limited and variable, an alternative and genetically modifiable non-human source of tissue would be valuable. We have generated cloned transgenic bovine embryos, 42% of which developed beyond 40 days. Dopamine cells collected from the ventral mesencephalon of the cloned fetuses 42 to 50 days post-conception survived transplantation into immunosuppressed parkinsonian rats and cells from cloned and wild-type embryos improved motor performance. Somatic cell cloning can efficiently produce transgenic animal tissue for treating parkinsonism.

Sexual harassment of Chinese college students with a focus on their awareness, experiences, responses, and expectations of institutional intervention to the problem was examined. 358 male and 491 female Chinese college students in Hong Kong participated. There were no gender differences in students' awareness of the phenomenon. Students' own experiences were less frequent than what they had heard about sexual harassment. Peer harassment occurred twice as frequently as faculty harassment. Compared to men, twice as many women said they had been sexually harassed. About one in four women students experienced various forms of sexual harassment and 1% were coerced into sexual activities during their college years by either teachers or peers. Students typically avoided and ignored the harassers and felt that the university should take up active roles in combating the problem. Comparisons with U.S. studies suggested that Chinese college students had a lower awareness and experience level in sexual harassment than U.S. students.

Ultrasonic absorption and velocity spectra in bovine serum albumin (BSA) aqueous solutions have been measured at 20 degrees C over the broad frequency range 0.1-1600 MHz in the pH range 1.5-13.2. Five different techniques were used: the plano-concave resonator, plano-plano resonator, pulse-echo overlap, Bragg reflection, and high-resolution Bragg reflection methods. The absorption spectrum at neutral pH was well fitted to the relaxation curve assuming a distribution of relaxation frequency with a high-frequency cutoff and long low-frequency tail. The relaxation behavior was interpreted in terms of various degrees of hydration of BSA molecules. At acid pH's, excess absorption over that at pH 7 was explained by double relaxation. The pH dependences of the relaxation frequency and maximum absorption per wavelength showed that the relaxation at about 200 kHz was related to the expansion of molecules and that at 2 MHz resulted from the proton transfer reaction of carboxyl group. At alkaline pH's, the excess absorption was explained by triple relaxation. The relaxation at about 200 kHz was associated with a helix-coil transition, and the two relaxations at 2 and 15 MHz were attributed to the proton transfer reactions of phenolic and amino groups, respectively. The rate constants and volume changes associated with these processes were estimated.

Luxatio erecta or inferior dislocation of the shoulder joint is rare and is caused by a hyperabduction injury. The clinical appearance is characteristic, with the arm locked in an elevated position. Radiographically, the shaft of the humerus is directed upwards and the humeral head lies inferior to the glenoid fossa, although not in contact with it. Attention should be given to possible complication, particularly concurrent fractures, as well as injury to the brachial plexus or the axillary artery.