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The effect of strain rate on mechanical properties of Al-2.3wt.%Mg alloy (AA5021) and commercial pure aluminum (purity 99.7wt.%: A1070) was investigated at room temperature. The tensile tests were conducted at strain rates from 1.0×10−4 to 1.0×103 s−1. The universal testing machine was used for strain rate 1.0×10-4 to 1.0×10−1 s−1. For the strain rate 1.0×100 s-1, the servohydraulic testing machine, which was developed by our laboratory, was used. The impact strain rate 1.0×103 s−1 was obtained using the split Hopkinson pressure bar method. The pure aluminum showed positive strain rate dependence of material strength at the investigated strain rates. In contrast, the Al-2.3wt.%Mg alloy showed the negative strain rate dependence at strain rates from 1.0×10−4 to 1.0×100 s−1. However, Al-2.3wt.%Mg alloy showed the positive strain rate dependence at strain rates from 1.0×100 to 1.0×103 s−1. It was surmised that the effect of dislocation locking by the solute Mg atoms became negligible at strain rate of approximately 1.0×100 s−1. It was confirmed that material properties for the Al-Mg alloy at the strain rate of 1.0×100 s−1 were important, since the strain rate dependence changed negative to positive around this strain rate.

The payload fairing in Japan is fixed by a lot of notched bolts. These notched bolts were fractured by axial impact tensile using the explosive devices to separate the fairing. In this case, the stress waves and the oscillations propagate, which may seriously damage the satellites. In this study, the impact deformation and the fracture behavior of notched titanium alloy bolt was investigated using a split Hopkinson pressure bar method. The notched bolt specimen was made of commercial Ti-6Al-4V alloy. The maximum load value was increased with increasing the displacement rate. It can be said that the strain rate dependence of strength for Ti-6Al-4V alloy appeared. From the observation of fracture surface using a scanning electron microscope, compared with the quasi-static test, it was clear that the irregularities of the fractured surface at the impact tensile test became rough. Therefore, it was found that the brittle fracture was mainly observed due to the increase in displacement rate, which may mean that the mode of fracture changes from the transgranular to the intergranular. It was surmised that this change of fracture mode was caused by the high strain rate due to stress concentration of the notched part.

Indentation is widely used to investigate the elastic and plastic properties of mechanical materials, which includes the strain rate sensitivity. The indentation exhibits an inhomogeneous strain distribution in contrast to compression and tensile tests with homogeneous deformation. Thus, the strain rate of the indentation may form the inhomogeneous distribution. Therefore, the effect of strain rate distribution of the indentation on pure aluminum with respect to the strain rate dependence of strength in order to clarify the effect of the strain rate on the indentation technique. First, the numerical simulation was established using the Cowper-Symonds equation as the dynamic constitutive equation. Secondary, the strain rate distribution was calculated from the equivalent plastic strain distribution. The strain rate distribution was quite different from the strain distribution, which showed that the strain rate at the crater rim was higher than that beneath the indenter. Finally, we try to perform the averaging of strain rate distribution in order to make an index of strain rate in the indentation. The average of strain rate distribution was calculated using the equivalent plastic strain above a boundary value that is the critical strain and the representative strain. There is correlation between the average strain rate and the loading curvature, which shows that the average strain rate can express as the representative of strain rate for the indentation technique.

The exact mechanism of exercise-induced hypoalgesia (EIH) in exercise therapy to improve chronic pain has not been fully clarified. Recent studies have suggested the importance of the ventral hippocampus (vHPC) in inducing chronic pain. We investigated the effects of voluntary running (VR) on FosB + cells and GABAergic interneurons (parvalbumin-positive [PV + ] and somatostatin-positive [SOM + ]) in the vHPC-CA1 in neuropathic pain (NPP) model mice. VR significantly improved thermal hyperalgesia in the NPP model. The number of the FosB + cells was significantly higher in partial sciatic nerve ligation-sedentary mice than in Sham and Naive mice, whereas VR significantly suppressed the FosB + cells in the vHPC-CA1. Furthermore, VR significantly increased the proportion of activated PV + and SOM + interneurons in the vHPC-CA1, and tracer experiments indicated that approximately 24% of neurons projecting from the vHPC-CA1 to the basolateral nucleus of amygdala were activated in NPP mice. These results indicate that feedforward suppression of the activated neurons via VR-induced activation of GABAergic interneurons in the vHPC-CA1 may be a mechanism to produce EIH effects, and suggested that disappearance of negative emotions such as fear and anxiety by VR may play a critical role in improving chronic pain., (© 2023. The Author(s).)

Continuing a survey of the chemistry of species of the largely continental African genus Vepris , we investigate a species previously referred to as Vepris sp. 1 of Congo. From the leaves of Vepris sp. 1 we report six compounds. The compounds were three furoquinoline alkaloids, kokusaginine (1), maculine (2), and flindersiamine (3), two acridone alkaloids, arborinine (4) and 1-hydroxy-3-methoxy-10-methylacridone (5), and the triterpenoid, ß-amyrin (6). Compounds 1-4 are commonly isolated from other Vepris species, compound 5 has been reported before once, from Malagasy Vepris pilosa , while this is the first report of ß-amyrin from Vepris . This combination of compounds has never before been reported from any species of Vepris . We test the hypothesis that Vepris sp. 1 is new to science and formally describe it as Vepris teva , unique in the genus in that the trifoliolate leaves are subsessile, with the median petiolule far exceeding the petiole in length. Similar fleshy-leathery four-locular syncarpous fruits are otherwise only known in the genus in Vepris glaberrima (formerly the monotypic genus Oriciopsis Engl.), a potential sister species, but requiring further investigation to confirm this phylogenetic position. We briefly characterise the unusual and poorly documented Atlantic coast equatorial ecosystem, where Vepris teva is restricted to evergreen thicket on white sand, unusual in a genus usually confined to evergreen forest. This endemic-rich ecosystem with a unique amphibian as well as plants, extends along the coastline from the mouth of the Congo River to southern Rio Muni, a distance of about 1,000 km, traversing five countries. We map and illustrate Vepris teva and assess its extinction risk as Endangered (EN B1ab(iii)+B2ab(iii)) using the IUCN, 2012 standard. Only three locations are known, and threats include port and oil refinery construction and associated activities, with only one protected location, the Jane Goodall Institute's Tchimpounga Reserve. Initial evidence indicates that the seeds of Vepris teva are dispersed by chimpanzees, previously unreported in the genus., Competing Interests: The authors declare that they have no competing interests., (© 2022 Langat et al.)

An aromatic alkaloid-rich 'absolute' extract from Vepris gossweileri inhibited Saccharomyces cerevisiae at 62.5 μg.mL -1 and Bacillus subtilis at 500 μg.mL -1 . A loss of activity upon fractionation indicated possible synergistic effects. Three new acridones, gossweicridone A ( 3 ), B ( 4 ) and C ( 5 ) and known compounds from the extract were inactive. Combinations of compounds showed that a sub-fraction containing mixtures of minor compounds with ( Ε )-caryophyllene augmented activity by 50-folds, with MIC values of 19.6 μg.mL -1 for S. cerevisiae and 375.0 μg.mL -1 for B. subtilis , demonstrating potent ΣFIC values of 0.02 and 0.375 respectively. From the active sub-fraction, three compounds were assigned as tecleanatalensine B, 13 S -hydroxy-9 Z ,11 E ,15 E -octadecatrienoic acid and normelicopine. In combination with ( Ε )-caryophyllene they separately demonstrated MIC values of 18 μg.mL -1 , 34 μg.mL -1 and 16 μg.mL -1 , respectively against S. cerevisiae . The synergistic combinations were more potent with addition of pheophytin A, suggesting that the synergistic antifungal effect of the extract is multi-layered.

N2 and CO2 gas permeability of mesoporous silica glass bearing photochromic indolinospironaphth[2,1-b][1,4]oxazine through a covalent linkage was controlled by photo-irradiation: the photo-isomerization of the spironaphthoxazine to the photomerocyanine form suppressed the gas permeation of the glass.

This study was designed to prove that survival of flaps was improved by the hypobaric oxygen training before making flaps. Wistar strain male rats weighing 200-250 grams were used as the experimental animals. Rats were kept in a hypobaric simulator two hours a day for two weeks, which was set to emulate a condition of 8000 meters above sea level (hypobaric oxygen training). When the hypobaric oxygen training was finished, flaps were elevated on the back of the rats. Survival rate of flaps were significantly increased at 7th post-operative day. But its effect has been diminished until the 3rd training day. The mechanism of hypobaric oxygen training was studied by blood cell count and measurement of serum prostglandin E level, micro-angiogram of the flap and the count of insulin particle in the dermis. Consequently, it is postulated that the mechanism of hypobaric oxygen training was not morphological and functional change in the flap vascularity but the cellular metabolic adaptation to the hypobaric state.

Use of a split-thickness scalp graft for coverage of the retroauricular area after elevation of a reconstructed auricle is reported. Because there is no morbidity of the donor site and the color and texture match is excellent, the scalp can be an ideal donor site for coverage of the retroauricular area of the reconstructed auricle.

Seventeen whole-breast tissue specimens of mammary cystic disease were prepared using Marcum's whole-mounting technique. Histological studies were performed on from 10 to 19 slides of tissue containing the suspected pathological foci. Cysts in the cleared breast tissues were numerous, and cyst walls were covered by single-layered duct epithelial cells with some apocrine metaplasia. The most notable findings were frequent minute carcinomatous foci next to the scattering of mammary cysts. The incidence of carcinoma among 17 mammary cystic disease patients was 8, or 47%. Each patient had from one to six minute carcinomatous foci--less than 1 mm in diameter and noninfiltrating. All patients were treated by subcutaneous total mastectomy and immediate breast reconstruction with the Natural-Y mammary prosthesis. In all 17 the results were good. With no hazardous complications. Steps toward immediate breast reconstruction are as imperative psychologically as the total glandectomy is clinically.

The abductor digiti minimi muscle flap is known as good tissue coverage for the lateral ankle and heel. For reconstruction of the distal portion of the foot, the distally based flap of this muscle can be useful, effectively utilizing the blood supply through the plantar arch communication. A case of frostbite of the right fifth toe is reported, which we successfully repaired with a distally based abductor digiti minimi muscle flap. In addition, some information on distally based use of the muscles of the foot is presented.

We introduce a simple method for correcting the inverted nipple in which there is preservation of the lactiferous duct, less surgical invasion, and negligible scar formation. Our method consists of two parts: releasing fibrous tissue around the lactiferous ducts, and keeping the nipple in the everted position with a bolster suture and milk suction pump.

The subcutaneous pedicle flap is useful for reconstruction of a relatively small defect, and there have been many reports on its use in the facial region. With careful manipulation and thought given to the selection of the patient, it is also applicable to the trunk and extremities. During the last 7 years, we have treated 80 patients who had subcutaneous pedicle flaps applied to various parts of the body (57 on the face, 12 on the trunk, and 11 on the extremities). Eleven representative patients are presented in this article. Based on our experience, we are now confident that the subcutaneous pedicle flap is useful to reconstruct a free border or transient area of different tissues, such as the eyebrow, eyelid, lip, and nose. In the trunk, e.g., in the buttock and the breast, it is useful to reconstruct the natural convexity. We prefer using the V-Y advancement type of subcutaneous pedicle flap rather than the transposition flap. To increase the mobility of the advancement flap, the distal portion of the flap is undermined just below the layer of the subdermal plexus. This may prevent postoperative bulkiness and facilitate the reconstruction of natural contour.

The response of serum prolactin (PRL) to thyrotropin-releasing hormone (TRH) was evaluated by radioimmunoassay in 6 normal women and 44 breast cancer cases. They were divided into the following 5 groups: group 1:6 normal women; group 2:10 preoperative patients with early breast cancer; group 3:13 preoperative patients with advanced cancer; group 4:13 postoperative patients with no recurrence of cancer for more than 2 years; group 5:8 postoperative patients with cancer recurrence. The maximum increment of serum PRL levels following the administration of TRH was significantly higher in groups 2, 3 and 5 than in groups 1 and 4. These results indicate that patients with recurrent breast cancer have a higher PRL response to TRH than those without recurrence of cancer.

Surgical and non-surgical procedures for the correction of Stahl's ear anomaly, more commonly found in Oriental races, are presented. The final postoperative appearance is aesthetically pleasing, acceptable, and encouraging to the patient with this deformity.

A one-stage repair was carried out for a prostato-membranous urethral stricture using an epilated gracilis myocutaneous flap. The follow-up has now lasted for 2 years and 6 months. The patient has been continent and able to pass urine with a good stream. This procedure is particularly suitable for reconstruction of the posterior bulbar and prostrato-membranous urethra which is difficult to repair by standard techniques.

The tissue PO2 level in the skin of rats injected with fluorocarbon (FC-43) was measured by the microelectrode method and by a transcutaneous monitor. It was found that the tissue PO2 in the animals injected with FC-43 was two to three times higher than that of the control group. Neither the administration of FC-43 nor the inhalation of systemic oxygen improved flap survival in the rats.

Modifications of the reverse-U operation of Tajima are described which remove the "plica vestibularis" and prevent recurrence of the nasal deformity by adding lining tissue to the deformed nasal cavity. Good results have been achieved in both primary repair in infants and secondary repair.

We investigated the effect of low-power laser irradiation on the survival of experimental skin flaps in rats. A gallium-aluminum-arsenide diode laser that was developed by the Japan Medical Laser Laboratory was used. The laser power was 15 mW and the wavelength 830 nm. Irradiation was carried out, either before or after flap elevation, in two groups of 20 Wistar strain rats. A third group of 20 rats served as controls. A caudally based skin flap, 3 X 9 cm, was designed on the back of each rat. Laser irradiation therapy was performed for 5 consecutive days for 6 minutes per flap per day, preoperatively in one group and postoperatively in the other. Seven days postoperatively, the survival areas of the flaps were measured and compared. The survival area was increased significantly in both groups receiving laser therapy, probably due to the observed proliferation of blood vessels around the irradiated points and an increase in blood flow.

A modification of McGregor's fan-shaped flap is described, based on the facial artery instead of the labial artery. The flap appears to have some advantages when compared with McGregor's original flap. A case of squamous cell carcinoma of the lower lip is presented in which the excisional defect was repaired with this flap.