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Since the demonstration of p-type gallium nitride (GaN) through doping with substitutional magnesium (Mg) atoms1,2, rapid and comprehensive developments, such as blue light-emitting diodes, have considerably shaped our modern lives and contributed to a more carbon-neutral society3–5. However, the details of the interplay between GaN and Mg have remained largely unknown6–11. Here we observe that Mg-intercalated GaN superlattices can form spontaneously by annealing a metallic Mg film on GaN at atmospheric pressure. To our knowledge, this marks the first instance of a two-dimensional metal intercalated into a bulk semiconductor, with each Mg monolayer being intricately inserted between several monolayers of hexagonal GaN. Characterized as an interstitial intercalation, this process induces substantial uniaxial compressive strain perpendicular to the interstitial layers. Consequently, the GaN layers in the Mg-intercalated GaN superlattices exhibit an exceptional elastic strain exceeding −10% (equivalent to a stress of more than 20 GPa), among the highest recorded for thin-film materials12. The strain alters the electronic band structure and greatly enhances hole transport along the compression direction. Furthermore, the Mg sheets induce a unique periodic transition in GaN polarity, generating polarization-field-induced net charges. These characteristics offer fresh insights into semiconductor doping and conductivity enhancement, as well as into elastic strain engineering of nanomaterials and metal–semiconductor superlattices13.The spontaneous formation of magnesium-intercalated gallium nitride superlattices by the interstitial intercalation of two-dimensional magnesium results in considerable compressive strain perpendicular to the layers, leading to enhanced hole transport. [ABSTRACT FROM AUTHOR]

Lanthanoid-doped Gallium Nitride (GaN) integrated into nanophotonic technologies is a promising candidate for room-temperature quantum photon sources for quantum technology applications. We manufactured praseodymium (Pr)-doped GaN nanopillars of varying size, and showed significantly enhanced room-temperature photon extraction efficiency compared to unstructured Pr-doped GaN. Implanted Pr ions in GaN show two main emission peaks at 650.3 nm and 651.8 nm which are attributed to 3P0-3F2 transition in the 4f-shell. The maximum observed enhancement ratio was 23.5 for 200 nm diameter circular pillars, which can be divided into the emitted photon extraction enhancement by a factor of 4.5 and the photon collection enhancement by a factor of 5.2. The enhancement mechanism is explained by the eigenmode resonance inside the nanopillar. Our study provides a pathway for Lanthanoid-doped GaN nano/micro-scale photon emitters and quantum technology applications. [ABSTRACT FROM AUTHOR]

As a newly developed technique to slice GaN substrates, which are currently very expensive, with less loss, we previously reported a laser slicing technique in this journal. In the previous report, from the perspective of GaN substrate processing, we could only show that the GaN substrate could be sliced by a laser and that the sliced GaN substrate could be reused. In this study, we newly investigated the applicability of this method as a device fabrication process. We demonstrated the thinning of GaN-on-GaN high-electron-mobility transistors (HEMTs) using a laser slicing technique. Even when the HEMTs were thinned by laser slicing to a thickness of 50 μm after completing the fabrication process, no significant fracture was observed in these devices, and no adverse effects of laser-induced damage were observed on electrical characteristics. This means that the laser slicing process can be applied even after device fabrication. It can also be used as a completely new semiconductor process for fabricating thin devices with thicknesses on the order of 10 μm, while significantly reducing the consumption of GaN substrates. [ABSTRACT FROM AUTHOR]

We have investigated the possibility of applying lasers to slice GaN substrates. Using a sub-nanosecond laser with a wavelength of 532 nm, we succeeded in slicing GaN substrates. In the laser slicing method used in this study, there was almost no kerf loss, and the thickness of the layer damaged by laser slicing was about 40 µm. We demonstrated that a standard high quality homoepitaxial layer can be grown on the sliced surface after removing the damaged layer by polishing. [ABSTRACT FROM AUTHOR]

Gallium nitride (GaN)-based devices surpass the traditional silicon-based power devices in terms of higher breakdown voltage, faster-switching speed, higher thermal conductivity, and lower on-resistance. However, heteroepitaxial GaN growths like GaN on sapphire are not suitable for power devices due to the threading dislocation densities as high as 108/cm2. Recently, homoepitaxial GaN growth has become possible thanks to the native GaN substrates with dislocation densities in the order of 104/cm2 but the extremely high cost of the GaN substrates makes the homoepitaxy method unacceptable for industrial applications, and the slicing of wafers for reusing them is an effective solution for cost reduction. In this study, we will investigate a route for slicing the GaN single crystal substrate by controlling the laser pulse energy and changing the distance between each laser shot. The 2D and 3D crack propagations are observed by a multiphoton confocal microscope, and the cross section of samples is observed by a scanning electron microscope (SEM). The results showed that two types of radial and lateral cracking occurred depending on the pulse energy and shot pitch, and controlling them was of importance for attaining a smooth GaN substrate slicing. Cross-sectional SEM images showed that at suitable pulse energy and distance, crack propagation could be controlled with respect to the irradiation plane. [ABSTRACT FROM AUTHOR]

GaN nanorods (NRds) with axial InGaN/GaN MQWs insertions are synthesized by an original cost-effective and large-scale nanoimprint-lithography process from an InGaN/GaN MQWs layer grown on c-sapphire substrates. By design, such NRds exhibit a single emission due to the c-axis MQWs. A systematic study of the emission of the NRds by time-resolved luminescence (TR-PL) and power dependence PL shows a diameter-controlled luminescence without significant degradation of the recombination rate thanks to the diameter-controlled strain tuning and QSCE. A blueshift up to 0.26 eV from 2.28 to 2.54 eV (543 nm to 488 nm) is observed for 3.2 nm thick InGaN/GaN QWs with an In composition of 19% when the NRds radius is reduced from 650 to 80 nm. The results are consistent with a 1-D based strain relaxation model. By combining state of the art knowledge of c-axis growth and the strong strain relieving capability of NRds, this process enables multiple and independent single-color emission from a single uniform InGaN/GaN MQWs layer in a single patterning step, then solving color mixing issue in InGaN based nanorods LED devices. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to identify independent predictive factors for return to sports (RTS) after anterior cruciate ligament (ACL) reconstruction in competitive-level athletes and to determine optimal cut-off values for these factors at 6 months after surgery.Methods: A total of 124 competitive athletes (50 males and 74 females; mean age, 17.0 years; preinjury Tegner activity scale > 7) who underwent primary ACL reconstruction were enrolled. Assessments at 6 months after surgery consisted of knee functional tests [quadriceps index, hamstrings index, and single-leg hop for distance (SLH)] and 2 self-report questionnaires [IKDC subjective score and ACL-Return to Sport after Injury scale (ACL-RSI)]. At 1 year after surgery, athletes were classified into the RTS group (n = 101) or non-RTS group (n = 23) based on self-reported sports activities. After screening possible predictive factors of RTS, multivariate logistic regression and receiver operating characteristic curve analyses were performed to identify independent factors.Results: Multivariate logistic regression analysis identified SLH (odds ratio, 2.861 per 10 unit increase; P < 0.001) and ACL-RSI (odds ratio, 1.810 per 10 unit increase; P = 0.001) at 6 months as independent predictors of RTS at 1 year after surgery. Optimal cut-off values of SLH and ACL-RSI were 81.3% (sensitivity = 0.891; specificity = 0.609) and 55 points (sensitivity = 0.693; specificity = 0.826), respectively.Conclusion: In competitive athletes, SLH < 81% and ACL-RSI < 55 points at 6 months after surgery were associated with a greater risk of unsuccessful RTS at 1 year after surgery. SLH and ACL-RSI at 6 months could serve as screening tools to identify athletes who have difficulties with returning to sports after ACL reconstruction.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: In animal studies after ACL reconstruction (ACL-R) using the bone-patellar tendon-bone (BTB), the graft-healing pattern was found to depend on the relationship between bone plug and the tunnel wall. This difference of graft-healing pattern could influence the postoperative morphological changes of the tunnel. However, no study has assessed the relationship between bone plug position and the change of tunnel morphology. Therefore, the main purpose of this study was to investigate the relationship between the bone plug position within femoral or tibial tunnel and morphological changes of each tunnel aperture in ACL-R using computed tomography.Methods: Subjects were 30 consecutive patients (six females and 24 males; mean age, 20.4 ± 5.4 years) who underwent primary ACL-R using BTB. The distance from the tunnel aperture to the tendon-bone junction (TBJ) at 2 weeks postoperatively, and tunnel aperture enlargement and tunnel wall migration from 2 weeks to 6 months postoperatively, were evaluated.Results: The distance from the femoral tunnel aperture to the TBJ in most cases was less than 2 mm, whereas the TBJ was located within the tibial tunnel. Femoral tunnel aperture was significantly enlarged (17.0 ± 11.7%) distally, and the tibial tunnel aperture was significantly enlarged (19.6 ± 12.5%) posterolaterally. Only the position at distal portion of femoral bone plug was correlated with femoral tunnel aperture enlargement (r = 0.454, p = 0.0015).Conclusion: Both femoral and tibial tunnel aperture were significantly enlarged distally and posterolaterally 6 months postoperatively. Only correlation between the position at distal portion of femoral bone plug and femoral tunnel enlargement were found, suggesting the deep plug position in the tunnel is a risk factor for femoral tunnel enlargement, highlighting the importance of accurately locating the TBJ just at the femoral tunnel aperture. Another option is to deviate the harvest site in the patellar tendon to match the shape of the TBJ and the tunnel aperture.Level Of Evidence: 4 (case series). [ABSTRACT FROM AUTHOR]

By alloying GaN with AlN the emission of AlGaN light-emitting diodes can be tuned to cover almost the entire ultraviolet spectral range (210-400 nm), making ultraviolet light-emitting diodes perfectly suited to applications across a wide number of fields, whether biological, environmental, industrial or medical. However, technical developments notwithstanding, deep-ultraviolet light-emitting diodes still exhibit relatively low external quantum efficiencies because of properties intrinsic to aluminium-rich group III nitride materials. Here, we review recent progress in the development of AlGaN-based deep-ultraviolet light-emitting devices. We also describe the key obstacles to enhancing their efficiency and how to improve their performance in terms of defect density, carrier-injection efficiency, light extraction efficiency and heat dissipation. This Review covers recent progress in AlGaN-based deep-ultraviolet light-emitting devices. The key technologies of how to improve their performance, carrier-injection efficiency, light extraction efficiency and heat dissipation are discussed. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to retrospectively compare the enlargement and migration of the femoral tunnel aperture after anatomic rectangular tunnel anterior cruciate ligament (ACL) reconstruction with a bone-patella tendon-bone (BTB) or hamstring tendon (HT) graft using three-dimensional (3-D) computer models.Methods: Thirty-two patients who underwent ACL reconstruction and postoperative computed tomography (CT) at 3 weeks and 6 months were included in this study. Of these, 20 patients underwent ACL reconstruction with a BTB graft (BTBR group), and the remaining 12 with an HT graft (HTR group). The area of the femoral tunnel aperture was extracted and measured using a 3-D computer model generated from CT images. Changes in the area and migration direction of the femoral tunnel aperture during this period were compared between the two groups.Results: In the HTR group, the area of the femoral tunnel aperture was significantly increased at 6 months compared to 3 weeks postoperatively (P < 0.05). The average area of the femoral tunnel aperture at 6 months postoperatively was larger by 16.0 ± 12.4% in the BTBR group and 41.9 ± 22.2% in the HTR group, relative to that measured at 3 weeks postoperatively (P < 0.05). The femoral tunnel aperture migrated in the anteroinferior direction in the HTR group, and only in the inferior direction in the BTBR group.Conclusions: The femoral tunnel aperture in the HTR group was significantly more enlarged and more anteriorly located at 6 months after ACL reconstruction, compared to the BTBR group.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

GaAs, InP, and their related compound semiconductors can be grown on native substrates, whereas such growth was not possible for group III nitride semiconductors in the 1970s and 1980s. Despite this drawback, researchers were able to use novel functions of group III nitride semiconductors by growing their thin films on nonnative substrates such as sapphire SiC and Si. [ABSTRACT FROM AUTHOR]

This study investigated the feasibility of using the cannibalistic habits of the mite Neoseiulus californicus (McGregor) and controlling the relative humidity (RH) to prolong the survival time during the storage or shipment of this predatory mite. Three-day-old mated and unmated females were individually kept at 25 ± 1 °C in polypropylene vials (1.5 mL), each containing one of the following items or combinations of items: a kidney bean leaf disk (L), N. californicus eggs (E), and both a leaf disk and the eggs (LE). Because the leaf disk increased the RH in the vials, the RH was 95 ± 2 % under the L and LE treatments and 56 ± 6 % under the E treatment. The median lethal time (LT) exceeded 50 days for the mated and unmated females under the LE treatment. However, it did not exceed 11 or 3 days for all females under the L or E treatments, respectively. Under the LE treatment, the mated and unmated females showed cannibalistic behavior and consumed an average of 5.2 and 4.6 eggs/female/10 days. Some of the females that survived for LT under each treatment were transferred and fed normally with a constant supply of Tetranychus urticae Koch. Unmated females were provided with adult males for 24 h for mating. Only females previously kept at LE treatment produced numbers of eggs equivalent to the control females (no treatment is applied). The results suggested that a supply of predator eggs and leaf material might have furnished nutrition and water vapor, respectively, and that this combination prolonged the survival time of N. californicus during storage. Moreover, this approach poses no risk of pest contamination in commercial products. [ABSTRACT FROM AUTHOR]

We report the selective-area growth of a gallium nitride (GaN)-nanorod-based InGaN/GaN multiple-quantum-well (MQW) core-shell structure embedded in a three-dimensional (3D) light-emitting diode (LED) grown by metalorganic chemical vapor deposition (MOCVD) and its optical analysis. High-resolution transmission electron microscopy (HR-TEM) observation revealed the high quality of the GaN nanorods and the position dependence of the structural properties of the InGaN/GaN MQWs on multiple facets. The excitation and temperature dependences of photoluminescence (PL) revealed the m-plane emission behaviors of the InGaN/GaN core-shell nanorods. The electroluminescence (EL) of the InGaN/GaN core-shell-nanorod-embedded 3D LED changed color from green to blue with increasing injection current. This phenomenon was mainly due to the energy gradient and deep localization of the indium in the selectively grown InGaN/GaN core-shell MQWs on the 3D architecture. [ABSTRACT FROM AUTHOR]

Purpose: Anterior knee pain related to the donor site is a frequent complication of anterior cruciate ligament reconstruction (ACLR) with bone-patellar tendon-bone autograft tissue. Even when hamstring tendon (HT) grafts are used instead, symptoms such as mild pain and discomfort can still occur. The purpose of this study was to elucidate the pathophysiology of anterior knee symptoms after ACLR with HT autografts.Methods: Fifty-seven patients (22 men and 35 women; mean age, 24.7 years) who underwent anatomic double-bundle ACLR with HT autografts were examined 6 months post-operatively. The presence of anterior knee symptoms, anterior knee laxity, range of motion, and muscle strength were assessed. Changes in patellar tendon and infrapatellar fat pad (IFP) morphology and blood flow were also evaluated using ultrasound. Potential variables affecting the presence of anterior knee symptoms were subjected to univariate analysis and multivariate logistic regression analysis to identify independent risk factors.Results: Six months post-operatively, the total incidence of anterior knee symptoms was 56.1 % (32/57). According to univariate analysis, age, quadriceps strength, and increased blood flow in the IFP were significantly associated with the presence of anterior knee symptoms. Multivariate logistic regression analysis revealed that increased blood flow in the IFP was an independent factor for the presence of anterior knee symptoms (odds ratio 5.0; 95 % confidence interval 1.3-19.9). There were no significant findings inside the patellar tendon.Conclusions: Increased blood flow in the IFP was identified as an independent factor for the presence of anterior knee symptoms 6 months after ACLR with HT autografts. The ultrasound evaluation can help to define precisely the origin of anterior knee symptoms after ACLR with HT autografts.Level Of Evidence: Case series with no comparison groups, Level IV. [ABSTRACT FROM AUTHOR]

Purpose: The displacement and deformation of the knee meniscus significantly affect its roles; however, little is known about the displacement and deformation patterns of a torn medial meniscus. The objective of this study was to evaluate quantitatively the patterns of displacement and deformation in horizontally torn medial menisci during knee flexion. Methods: Twenty patients with horizontally torn medial menisci underwent three-dimensional (3-D) magnetic resonance imaging at varying degrees of knee flexion, and 3-D computer models of the tibia, tibial articular cartilage, and meniscus were generated. Based on these, the size of the horizontal tear (% tear) was evaluated and defined as the circumferential ratio between the length of the horizontal tear and that of the entire meniscus. The 3-D meniscus models were automatically superimposed over images taken at 0, 20, 40, and 60° of knee flexion by the voxel-based registration method. Meniscal motion and deformation during knee flexion were visualized and quantitatively calculated on the mid-sagittal plane. Correlations between the size of horizontal tear, displacement/deformation of torn menisci, and clinical symptoms were evaluated after conservative treatment for 3 months. Results: The % tear was 35.7 ± 12.5 % (range 13.7-55.5 %). During knee flexion, all torn menisci moved posteriorly, with gradual widening of horizontal and vertical gaps ( p < 0.05). A direct correlation was observed between % tear and change in the vertical tear gap during knee flexion ( p < 0.05). There was an inverse correlation between Lysholm score and % tear ( p < 0.05). Conclusion: Medial meniscal horizontal tears widen and deform during knee flexion, and % tear correlates with the change in the vertical gap. Patients with a lower % tear are more capable of performing activities of daily living after conservative treatment. This method may help clarify the cause of pain in patients with medial meniscus tears as well as facilitate the selection of an appropriate treatment plan. Level of evidence: Case series, Level IV. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical outcome of anatomical double-bundle anterior cruciate ligament (ACL) reconstruction using multistranded hamstring tendons via an outside-in approach. Methods: One hundred and twenty-one patients (mean age 28 ± 10 years) who underwent ACL reconstruction were examined. Using an outside-in femoral drill guide, an upper femoral tunnel for the anteromedial (AM) graft was created just below the superior articular cartilage margin of the medial wall of the lateral condyle through a small incision. A lower femoral tunnel for the posterolateral (PL) graft was drilled in the centre of the inferior-posterior half of the attachment area behind the resident's ridge in the same manner. Two tibial tunnels were created at the centre of the AM and PL bundle footprints of a normal ACL. Patients were evaluated at 24 months postoperatively. Results: According to the IKDC form, 52 knees (43 %) were graded as normal, 64 (53 %) as nearly normal, 1 (1 %) as abnormal and 4 (3 %) as graft rupture due to re-injury. Loss of knee extension of <5° was observed in one patient (1 %). Among 111 patients who were directly evaluated, none showed loss of flexion of <5°. Lachman sign was negative in 103 patients (93 %), while the pivot shift test result was negative or equivalent to that of the contralateral healthy knee in 103 patients (93 %). The mean side-to-side difference in anterior laxity at manual maximum force with the KT-2000 arthrometer was 0.9 ± 1.1 mm, and 94 % of patients showed a range between −1 and +2 mm. Conclusion: The anatomical double-bundle outside-in ACL reconstruction provided a satisfactory short-term outcome. Level of evidence: Case series, Level IV. [ABSTRACT FROM AUTHOR]

The present study was performed to examine the reliability of ultrasound in evaluating patellar mobility in the superior-inferior direction. Twelve healthy men volunteered for the study. Patellar mobility in the superior-inferior direction during isometric knee extension contraction with the knee immobilized in a semi-flexed knee brace was measured using ultrasound. Both intra-observer and inter-observer reliability were assessed by intra-class correlation coefficients (ICCs). Bland-Altman analysis was used for assessing agreement between measurements. ICC values were excellent for both intra-observer and inter-observer reliability at 0.97 and 0.93, respectively. In 95 % of measurements, the same observer measured within −0.55 to 0.61 mm, while different observers measured within −0.82 to 0.85 mm. In conclusion, patellar mobility in the superior-inferior direction during an isometric knee extension exercise can be reproducibly measured using ultrasound. The level of evidence: VI (basic study of a novel evaluation method). [ABSTRACT FROM AUTHOR]

Tiny agricultural pests such as spider mites (Acari: Tetranychidae) attached to seedlings grown outdoors often invade greenhouses, thereby triggering pest outbreaks. To solve the problem, we examined whether differences in anoxia tolerance between animals and plants would permit the application of an anoxic environment to control spider mites without the aid of acaricides. Under an anoxic environment created by using a commercial deoxidant at 25 °C, the time for 50 % mortality of eggs, non-diapausing adults (summer form), and diapausing adults (winter form) were 6.1, 5.5, and 23.6 h, respectively, for Tetranychus urticae Koch and 5.4, 3.9, and 23.2 h, respectively, for Tetranychus kanzawai Kishida. With anoxia for 12 h, no eggs and non-diapausing adults survived in either species, whereas most diapausing adults (98 % for T. urticae and 88 % for T. kanzawai) survived. Under this treatment, host Phaseolus vulgaris L. seedlings showed serious physiological disorders in their primary leaves and apical buds, and unusual lateral buds developed in the cotyledon axils. The spider mites acquire anoxia tolerance during diapause, but anoxia can potentially control them during the summer if no negative effects are observed in the treated seedlings. [ABSTRACT FROM AUTHOR]

We investigated the rapid cold hardening (RCH) response in the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). On direct exposure, ≤2 % of adult females survived −10 °C for 2 h. However, when acclimatized first at 5 °C for 1 h, 75 % of females survived. RCH could also be induced by acclimatization at 30 °C for 2 h or anoxia (oxygen-free nitrogen) for 1-2 h. All immature stages showed enhanced survival when acclimatized at 5 °C for 2 h before exposure to −10 °C. Acclimatization at 30 °C induced RCH only in eggs and deutonymphs, and anoxia was effective for eggs, larvae, and deutonymphs. The variability among immature stages may be attributed to the cost associated with the acclimatization treatments. Our findings suggest that RCH may promote the survival of N. californicus during unexpected changes in temperatures, and can be an important feature particularly when this natural enemy is introduced to non-native environments. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to evaluate the entire course of ACL grafts on coronal oblique MR images, focusing on differences in graft morphology and graft-to-tunnel healing among single-bundle (SB), double-bundle (DB), and triple-bundle (TB) reconstructions. Methods: Eighty-three patients underwent anatomical ACL reconstruction using the semitendinosus tendon. SB reconstruction was performed on 20 patients, DB on 29 patients, and TB on 34 patients. The anteromedial-bundle (AMB) and posterolateral-bundle (PLB) images were extracted from coronal oblique images of grafts at 6 months to visualize their entire course. Signal intensity of grafts was measured independently in three regions: (1) intra-femoral tunnel region, (2) intra-articular region, and (3) intra-tibial tunnel region, followed by calculation of the signal-to-noise quotient (SNQ). To evaluate graft-to-tunnel healing, T2-weighted images were examined for the presence of a high signal-intensity lesion between the graft and bone tunnel around the tunnel aperture. Results: AMB images showed that SB graft was thick throughout the entire course, while DB graft was thinner than SB graft. TB graft showed a fan shape approaching the tibial tunnels. The SNQ in the femoral tunnel of SB graft was significantly lower than in the DB and TB grafts. High signal-intensity lesions were frequently observed around the femoral tunnel aperture in PLB images of DB and TB grafts compared to SB grafts. Conclusion: Gross morphology of TB grafts resembled that of the natural ACL. However, the graft-to-tunnel healing around the femoral tunnel seemed to be insufficient in PLB images of DB and TB compared to SB grafts. Level of evidence: III. [ABSTRACT FROM AUTHOR]

The silk produced by the group-living mite Tetranychus urticae provides group protection and is used as an informative material during habitat settlement, egg laying, mating, and dispersal events. In this context, cues contained in the silk and other materials produced by mites [eggs, black faeces (BF) and white faeces + silk (WFS)] were investigated. Chemical compounds were extracted by hexane or methanol, and choice tests were used to determine the individual attractiveness of each extract. For both solvents, individuals did not respond to the extract from eggs and WFS. BF extracts were attractive for both solvents. After separating the BF methanol extract into four different chemical components using thin layer chromatography, no component was determined to be responsible for mite attraction. This work supports the evidence that the faeces of T. urticae do contain substances that promote behavioural changes. Not particular chemical compounds but combinations of them seem to induce the mites' preference. Moreover, the response of mites to chemicals seemed to be context dependent as mites belonging to populations with different densities differed in their attraction to BF extracts. [ABSTRACT FROM AUTHOR]

Low air temperature accompanied with high humidity is effective for long-term cold storage of the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). To further improve this storage method, we investigated the effect of pre-storage nutrition on survival during storage and on post-storage quality in terms of survival, oviposition, and progeny viability. The predatory mite was fed from the egg to adult stage on the diapausing two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), non-diapausing spider mites, or Japanese pear pollen, Pyrus pyrifolia Nakai. Newly emerged N. californicus adult females and males were mated, and then both were stored at 7.5 °C and a vapor pressure deficit of 0.0 kPa for up to 75 days. Survival during storage and post-storage quality was significantly better with the diapausing spider mite diet than with the other diets. No effects on the survival or sex ratio of the progeny of the stored adults were observed, regardless of diet or storage duration. Providing diapausing spider mites as a pre-storage diet therefore significantly improves the long-term storage of N. californicus. We discuss the possibility that ingestion of the cryoprotectants, antioxidants, and energy reserves that are present in rich amounts in diapausing spider mites mitigates chilling injury. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1038/s41598-022-10610-4. The original version of this Article contained a repeated error where the symbol for micrometres "µm" was incorrectly given as millimetres "mm" in the Introduction, Experiments, Results and discussion, Figure 2 legend and the Conclusion. [Extracted from the article]

The present study investigated whether long-term cold storage at high relative humidity (RH) affected the quality of the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) in terms of its survival and reproduction. For this purpose, we examined biological traits at the end of storage and during the post-storage period. Mated females three days after adult emergence were stored individually in 1.5-ml vials for 15, 30, 45, 60, or 75 days at 5.0 ± 0.3°C and RH of 99 ± 0.1% under continuous darkness. At the end of the storage period, 94-100% of females had survived when the storage period was ≤30 days, but percent survival decreased with longer storage. After storage, female survival and oviposition rates were equivalent to un-stored females at 24 ± 1°C, RH of 93 ± 2%, and a photoperiod of LD 16:8 h. The quality of progeny (hatchability, survival to adulthood, and sex ratio) of stored females was not affected by storage periods as long as 60 days. These results indicate that storage using the tested method can preserve N. californicus for at least 30 days without any degradation. [ABSTRACT FROM AUTHOR]

To determine the optimum air temperature and water vapor pressure deficit (VPD) for the storage of the predatory mite, Neoseiulus californicus, 3-day-old mated females were stored at air temperatures of 0, 5, 10, or 15 °C and VPDs of 0.1, 0.3, or 0.5 kPa for 10, 20, or 30 days. At 10 °C and 0.1 kPa, 83 % of females survived after 30 days of storage; this percentage was the highest among all conditions. VPDs of 0.3 and 0.5 kPa regardless of air temperature, and an air temperature of 0 °C regardless of VPD were detrimental to the survival of the females during storage. Since the highest survival was observed at 10 °C and 0.1 kPa, the effect of the storage duration on the post-storage quality of the stored females and their progeny was investigated at 25 °C to evaluate the effectiveness of the storage condition. The oviposition ability of the stored females, hatchability, and sex ratio of their progeny were not affected even when the storage duration was extended to 30 days. Although a slight decrease in the survival during the immature stages of progeny was observed when the storage duration was ≥20 days, the population growth of N. californicus may not be affected when individuals stored in these conditions are applied to greenhouses and agricultural fields. The results indicate that mated N. californicus females can be stored at 10 °C and 0.1 kPa VPD for at least 30 days. [ABSTRACT FROM AUTHOR]

We developed a computer-based system for controlling water vapor conditions (i.e., humidity) using a two-flow method in which streams of humidified and dehumidified air were combined in an acrylic container. The flow rate of each stream was independently controlled to adjust relative humidity (RH). In this system, humidification from 15 to 90 % RH and dehumidification from 90 to 15 % RH at an air temperature (AT) of 25 °C were properly operated with short time constants of 4.3 and 10 min, respectively. Tetranychus urticae egg hatchability was then examined at 20-95 % RH and 25 °C AT. The coefficients of variation of RH were low (0.3-1.5 %). Egg hatchability in a polystyrene Petri dish was lower at 20 % RH than at 70-95 % RH. A delay in hatching was also observed at 70 % RH for eggs tested on a leaf disk placed on water-soaked cotton; this delay was attributed to the AT being 1.4 °C lower on the leaf surface than on the inner surface of the dish. Our system is expected to be useful for further examination of ecological and behavioral responses in pest mites and for developing novel physical control measures using water vapor. [ABSTRACT FROM AUTHOR]

The diapause response of the Kanzawa spider mite (KSM), Tetranychus kanzawai, was examined. KSMs were reared in aluminum bottles at 18°C with different combinations of light and dark periods created by the light-control unit. The developmental periods for all immature stages tended to decrease as the light period increased. The photoperiodic response curve for diapause induction showed that the critical (=50% diapause) light period was around 13 h days. No diapause induction was observed when the light period was longer than 13.5 h days or under continuous light. At 13-h days light period, the developmental period for deutonymphal stage as well as for the total immature stages was longer in diapaused females than in non-diapaused females. These results indicate that immature development as well as diapause induction are affected by photoperiod and further suggest that diapause-inducing stimuli prolong the developmental period especially for the deutonymphal stage of KSMs. [ABSTRACT FROM AUTHOR]

We developed an improved space-saving system consisting of a netbook computer, microcontrollers, aluminum bottles with white light-emitting diodes (LEDs), and an incubator. In this system, light and dark periods, light intensity, and night-interrupting light conditions (i.e., period, intensity, and timing) can be independently controlled in each bottle with a pulse-width modulator (PWM). Scheduled photoperiodic conditions with less fluctuation in air temperature were successfully realized with this system. Night-interrupting light conditions that may prevent diapause induction and subsequent overwintering were examined using this system to establish a novel strategy for nonchemical control of the two-spotted spider mite, Tetranychus urticae Koch. The results show that diapause incidence decreased as the cumulative intensity of night-interrupting light increased. Taken together, data show that this system can provide an accurate and space-efficient means of investigating the photoperiodic responses of insects and mites without unwanted fluctuations in air temperature, thus contributing to development of a lighting-based pest-control method in commercial agricultural fields. [ABSTRACT FROM AUTHOR]

The objective of this article is to describe the clinical outcome of the transitional double-bundle procedure for anatomical ACL reconstruction. Subjects included 78 patients (average age 25 years) who had undergone ACL reconstruction with the transitional double-bundle procedure with multi-stranded hamstring tendons. The femoral socket for the anteromedial (AM) graft was created at 5–6 mm from the mid-sagittal line of the intercondylar notch at 2:00 or 10:00, and that for the posterolateral (PL) graft was drilled adjacent to the AM socket at 3:00 or 9:00. For the tibial side, two tunnels were made at the center of the footprint of the AM and PL bundles of the normal ACL. Patients were evaluated at 24 months or longer postoperatively based on the IKDC Knee Examination Form. Subjectively, 32 knees (41%) were graded as normal; 41 (53%), as nearly normal; 4 (5%), as abnormal; and 1 (1%) as graft rupture by re-injury. The average side-to-side difference in anterior laxity at manual maximum force with the KT-2000 arthrometer was 0.9 mm ± 1.2. Seventy patients (93%) had a range between −1 mm and 2 mm. In conclusion the transitional double-bundle ACL reconstruction provided a satisfactory outcome after a short-term follow-up. [ABSTRACT FROM AUTHOR]

Anti-predator defenses provided by complex webs of Tetranychus mites can severely impede the performance of generalist predatory mites, whereas this may not be true for specialist predatory mites. Although some specialist predatory mites have developed morphological protection to reduce the adverse effects of complex webs, little is known about their behavioral abilities to cope with the webs. In this study, we compared thread-cutting behavior of three specialist predatory mites, Phytoseiulus persimilis, Neoseiulus womersleyi and N. californicus, exhibited inside the complex web of T. urticae. No major difference was observed among them in the basic pattern of this behavior, using chelicerae and palps, and in the number of silken threads severed while moving inside the web. These results and observations suggest that each predator species cut many sticky silken threads to move inside the complex web without suffering from serious obstruction. [ABSTRACT FROM AUTHOR]

To clarify the importance of the femoral socket location in bi-socket Anterior cruciate ligament (ACL) reconstruction. Subjects included 261 patients with an average age of 26 years who received ACL reconstruction via the high-femoral socket procedure (Group H) and 43 patients with an average age of 29 years who received ACL reconstruction via the low-femoral socket procedure (Group L) with a minimal follow-up of 24 months. In Group H, the femoral sockets were created at 1:00 or 11:00 and 2:00–2:30 or 9:30–10:00 of the intercondylar notch. In Group L, the two femoral sockets were drilled at 2:00 or 10:00 and 3:00 or 9:00. For the tibial side, a single tunnel was made at the center of the footprint. Evaluation was performed based on the IKDC Knee Examination Form. While 137 knees (52%) were graded as normal, 100 (38%) as nearly normal, 8 (3%) as abnormal, and 2 (1%) as severely abnormal with 14 (5%) re-injury in Group H, 38 knees (74%) were graded as normal, and 7 (16%) as nearly normal with 3 (7%) re-injury in Group L, showing a better subjective evaluation ( P = 0.007). The average side-to-side differences in anterior laxity at manual maximum force with the KT-1000 were 1.1 ± 1.6 mm for Group H and 1.0 ± 1.6 mm for Group L without statistically significant differences excluding re-injured cases. There were 204 patients (83%) from Group H and 33 (83%) from Group L with values between −2 and 2 mm, while 228 (92%) patients from Group H and 38 (95%) from Group L had values distributed between −3 and 3 mm. While the bi-socket ACL reconstruction provided objectively satisfactory clinical outcomes in more than 90% of the patients, the low-femoral socket placement was found to subjectively achieve better outcomes. [ABSTRACT FROM AUTHOR]

Artificial lighting is a merit of a 'plant factory', which might be utilized to suppress an increase in pest population. We investigated the effects of extending the light phase on diapause induction in the two-spotted spider mite (TSSM), Tetranychus urticae. TSSM were reared at 18°C under light phases ranging from 2 to 64 h combined with a constant dark phase of 16 h in aluminum bottles, with white light emitting diodes attached inside to minimize fluctuations in air temperature between the light and dark phases. Diapause was induced in adult TSSM females when the light phase was 24 h or shorter, and diapause induction was inhibited when the light phase extended over 32 h. The development of deutonymphs was delayed under a diapause-inducing photoperiod. Diapause inducing photoperiods may suppress an increase in the TSSM population, by slowing down development and reproduction. [ABSTRACT FROM AUTHOR]

Group-III-nitride semiconductors have shown enormous potential as light sources for full-colour displays, optical storage and solid-state lighting. Remarkably, InGaN blue- and green-light-emitting diodes (LEDs) emit brilliant light although the threading dislocation density generated due to lattice mismatch is six orders of magnitude higher than that in conventional LEDs. Here we explain why In-containing (Al,In,Ga)N bulk films exhibit a defect-insensitive emission probability. From the extremely short positron diffusion lengths (<4 nm) and short radiative lifetimes of excitonic emissions, we conclude that localizing valence states associated with atomic condensates of In–N preferentially capture holes, which have a positive charge similar to positrons. The holes form localized excitons to emit the light, although some of the excitons recombine at non-radiative centres. The enterprising use of atomically inhomogeneous crystals is proposed for future innovation in light emitters even when using defective crystals. [ABSTRACT FROM AUTHOR]

Phyto traps were attached to twigs, main branches and trunks of Japanese pear trees in central Japan in autumn of 2004, to evaluate the effectiveness of the trap as a tool to study overwintering phenology of arboreal phytoseiid mites. A subset of the traps was inspected and replaced at two-weeks intervals ("short-term Phyto trap"), in order to evaluate movement of phytoseiid mites on the trees in a short-term. The remaining traps were left undisturbed and collected monthly from January to May 2005 ("long-term Phyto trap"), to know what species overwinter in the traps and when they leave them. Most phytoseiid mites were collected in the traps on twigs. The most abundant phytoseiid species was Typhlodromus vulgaris Ehara. In the short-term traps on twigs, adult females and males of T. vulgaris were collected until mid-November 2004, when the pear trees became completely defoliated, but few mites were collected from December to April. On the other hand, adult females of T. vulgaris were abundant in the long-term traps on twigs sampled from January to April, but other stages of mites were never collected. These results indicate that T. vulgaris had moved to the long-term traps by late November, and that only adult females had overwintered in the traps. These females began to move and reproduce in early May. By that time immature developmental stages of T. vulgaris were also recorded in the short- and long-term Phyto traps. Our results confirmed that the Phyto trap was a useful tool for estimating overwintering phenology of phytoseiid mites on trees. [ABSTRACT FROM AUTHOR]

Objectives: Leaflet folding plasty was introduced for avoiding systolic anterior motion and coronary artery injury after mitral valve repair. We report the application and early outcome of this technique for mitral valve regurgitation. Methods: From January 1997 to January 2004,16 patients with mitral valve regurgitation were operated on using leaflet folding plasty. The group comprised 9 men and 7 women, with a mean age of 61.6 years. There were 15 patients with degenerative and 1 with ischemic mitral valve disease. The causes of mitral regurgitation were posterior mitral leaflet prolapse in 11 patients and commissural prolapse in 5 patients. Results: Mitral valve reconstruction could be performed in all patients. There were no perioperative deaths. Postoperative mitral regurgitation fell to 0.13±0.52 compared with 3.6±0.51 preoperatively. Systolic anterior leaflet motion was not observed in any patients after the procedure. The mean follow-up period was 22 months. There were no late deaths and reoperation was not required during follow-up. Conclusions: Early outcome of leaflet folding plasty for mitral valve repair was satisfactory. This technique may have advantages to accomplish mitral valve repair safely in patients with mitral regurgitation due to posterior or commissural prolapse. [ABSTRACT FROM AUTHOR]

The hemostatic effect of tranexamic acid (TA) was evaluated in patients undergoing coronary artery bypass grafting (CABG). The subjects were 33 serial patients who underwent elective CABG performed by the same team between January 1997 and April 2000. They were divided into a group that received TA ( n=15) and a non-TA control group ( n=18). The TA group received 50mg/kg of TA intravenously before starting cardiopulmonary bypass (CPB) and 25 mg/kg immediately after CPB. Blood loss from the end of CPB to completion of surgery (post-CPB), as well as during the first 6h (BL6), 6–12 h (BL6–12), 12–18h (BL12–18), and 18–24h after surgery (BL18–24), was compared between the two groups. The time of chest tube removal, the volume of blood transfused, and graft patency were also compared. The blood loss at BL6, BL6–12, BL12–18, and BL18–24, as well as the blood transfussion volume, were all significantly ( P<0.05) lower in the TA group than in the control group. There was no significant difference in graft patency between the two groups. In CABG patients, TA reduced blood loss without affecting graft patency, suggesting that it is useful in this setting. [ABSTRACT FROM AUTHOR]

Studies the process of egg formation in the body cavity of a phytoseiid mite, for examining the fertilization of male eggs. Formation of yolk granules after the insemination process; Presence of yolk granules in the eggshell due to fusion of two pronuclei; Expansion of ova in the eggshell leading to fertilization of the male egg.

Focuses on the effect of prey density on sex ratio of two predacious mites. Observation on the sex ratio of the two mites; Characteristics of the progeny in the two mites.

Focuses on the prey stage preference and feeding behavior of the first to third instar larvae and adult females of Oligota kashmirica. Change in the number of mites eaten with the growth of predator larvae; Prey preferences of adult female insects; Types of foraging behavior shown by predator larvae.

Five cases of pancreatic serous cystadenoma were examined pathologically, and their nuclear DNA ploidy patterns were determined. Four were unifocal tumors, and one was a multifocal tumor. The four unifocal tumors were typical serous cystadenomas. However, the multifocal tumor exhibited an increased N/C ratio, irregular nuclear margins, various-sized nuclei, coarse nuclear chromatin, and neural invasion. All tumor cells were stained with antiCA19-9 but none with antiCEA. In the antiCA19-9 staining, the four unifocal tumors and the tumors of the pancreatic tail in the multifocal case were positive only on the apical membrane, whereas the tumor cells of the pancreatic head in the multifocal case were positive within the whole cytosol. The unifocal tumors were diploid with a DNA Index (DI) of 1.0 and proliferation indices (PI) from 4.9 to 20.9% with a mean of 14.4%. In the multifocal case, the tumor in the pancreatic head was aneuploid (DI = 1.9) and had a PI of 27.8%. The multifocal sites in the pancreatic body were aneuploid (DI = 1.9) with a PI of 22.4%. We suggest that the biological property of serous cystadenoma should be revisited. [ABSTRACT FROM AUTHOR]

The pathological findings in three cases of solid and cystic tumor (SCT) of the pancreas were compared with the nuclear DNA histogram obtained by flow cytometry. One case involved maligant SCT with liver metastases. Two of the cases were benign SCT. In the malignant SCT, cellular atypia and mitotic figures were extensively observed. The proliferation index (PI) was 25, and the DNA index (DI) was 1.65. In the benign SCT, cellular atypia and mitotic figures were rarely observed. The PI was 8 and 13, respectively, and the DI was 1.0 in both cases. The proliferative activity and the biological malignant potential of the malignant SCT were thought to be higher than those of the benign SCT. [ABSTRACT FROM AUTHOR]

A case of multifocal pancreatic serous cystadenoma with atypical cells is reported. The patient was a 72-yr-old female who complained of jaundice. The distal common bile duct was obstructed, and the proximal bile duct was remarkably dilated on cholangiography. The main portal vein was obstructed and collateral vessels had developed on portal angiography. Total pancreatectomy was performed. The resected specimen contained one tumor in the head of the pancreas, five in the body, and one in the tail. The tumors of the head and body were morphologically the same. Microscopically, both contained spongelike multilocular cysts on their cut surfaces. These cysts were covered with low cuboid epithelium containing clear cystoplasm and abundant glycogen. Neural invasion was also found. The tumor cells exhibited an increased N/C ratio, variable nuclear size, irregular nuclear margins, and coarse nuclear chromatin. These tumors had aneuploid nuclear DNA with a DNA index of 1.9 and a proliferation index of 0.28. We feel that it is necessary to reconsider the biological concept of serous cystadenoma. [ABSTRACT FROM AUTHOR]

The effects of the Si doping level on the recombination dynamics and carrier (exciton) localization in modulation-doped GaN/Al0.07Ga0.93N multiple-quantum-well (MQW) structures were studied by means of photoluminescence (PL) and time-resolved PL measurements. All samples with different doping levels show a QW emission which is blue shifted with respect to the 3.48 eV PL peak from the GaN buffer layer. The decay time at the peak position remains nearly constant in the range of 320–420 ps at 2 K for all doping levels. For the undoped and low doped samples (3 × 1018 cm−3), which have less free electrons in the QWs, a non-exponential PL decay behaviour at 2 K is attributed to localized exciton recombination. The more highly doped samples (5 × 1018 cm−3 to 1020 cm−3) show almost exponential decay curves at 2 K, suggesting the recombination of free electrons and localized holes. The internal polarization-induced fields of the medium and highly-doped samples are partly screened by the electrons originating from the doping in the barriers. The emission peaks in time delayed PL spectra of these samples exhibit almost no shift as time evolves. Only the PL peak of the undoped and low-doped samples shows a redshift with time delay, related to the photogenerated carriers []. The decay time for the undoped sample shows non-exponential behaviour typical for localized excitons in III-N QWs. The same behaviour of decay time as a function of emission energy has been reported for InGaN QWs []. [ABSTRACT FROM AUTHOR]

Core–shell nanorods (NRs) with InGaN/GaN quantum wells (QWs) are promising for monolithic white light-emitting diodes and multi-color displays. Such applications, however, are still a challenge because intensity of the red band is too weak compared with blue and green. To clarify this problem, we measured photoluminescence of different NRs, depending on power and temperature, as well as with time resolution. These studies have shown that dominant emission bands come from nonpolar and semipolar QWs, while a broad yellow-red band arises mainly from defects in the GaN core. An emission from polar QWs located at the NR tip is indistinguishable against the background of defect-related luminescence. Our calculations of electromagnetic field distribution inside the NRs show a low density of photon states at the tip, which additionally suppresses the radiation of polar QWs. We propose placing polar QWs inside a cylindrical part of the core, where the density of photon states is higher and the well area is much larger. Such a hybrid design, in which the excess of blue radiation from shell QWs is converted to red radiation in core wells, can help solve the urgent problem of red light for many applications of NRs. [ABSTRACT FROM AUTHOR]

Growth of AlxGa1−xN layers (0 ≤ x ≤ 1) simultaneously on polar (0001), semipolar (10 1 ¯ 3) and (11 2 ¯ 2 ), as well as nonpolar (10 1 ¯ 0 ) and (11 2 ¯ 0 ) AlN templates, which were grown on planar sapphire substrates, has been investigated by metal-organic vapour phase epitaxy. By taking into account anisotropic in-plane strain of semi- and non-polar layers, their aluminium incorporation has been determined by x-ray diffraction analysis. Optical emission energy of the layers was obtained from room-temperature photoluminescence spectra, and their effective bandgap energy was estimated from room-temperature pseudo-dielectric functions. Both x-ray diffraction and optical data consistently show that aluminium incorporation is comparable on the polar, semi- and non-polar planes. [ABSTRACT FROM AUTHOR]