A Case Study of Cloud-top Kelvin–Helmholtz Instability Waves near the Dendritic Growth Zone

Kelvin-Helmholtz instability (KH) waves have been broadly shown to affect the growth of hydrometeors within a region of falling precipitation, but formation and growth from KH waves at cloud top needs further attention. Here, we present detailed observations of cloud-top KH waves that produced a snow plume that extended to the surface. Airborne transects of cloud radar aligned with range height indicator scans from ground-based precipitation radar track the progression and intensity of the KH wave kinetics and precipitation. In-situ cloud probes and surface disdrometer measurements are used to quantify the impact of the snow plume on the composition of an underlying supercooled liquid water (SLW) cloud and the snowfall observed at the surface. KH wavelengths of 1.5 km consisted of ~750-m-wide up- and downdrafts. A distinct fluctus region appeared as a wave-breaking cloud top where the fastest updraft was observed to exceed 5 m s−1. Relatively weaker updrafts of 0.5-1.5 m s−1 beneath the fluctus and partially overlapping the dendritic growth zone were associated with steep gradients in reflectivity of −5 to 20 dBZe in as little as 500 m depths due to rapid growth of pristine planar ice crystals. The falling snow removed ~80% of the SLW content from the underlying cloud and led to a twofold increase in surface liquid equivalent snowfall rate from 0.6 to 1.3 mm hr−1. This paper presents the first known study of cloud-top KH waves producing snowfall with observations of increased snowfall rates at the surface.

Antibacterial Properties of PEO/PVA Nanofibers containing Juniper Leaf Extract

As the resistance of bacteria to antibiotics has become a rising issue, the discovery of new antibiotics with minimal side effects is more crucial. In this study, the antibacterial properties of a plant extract were assessed by investigating the antimicrobial effects of methanolic extract of Juniper leaf on standard microbial strains in skin infections. In order to compare different methods, the disk diffusion method sample containing 400 μg.ml-1 of Juniper extract, the well-established method samples containing 400 μg.ml-1 of Juniper extract, 48% samples of blank disk nanofibers method and 48% samples of round coverslip were selected due to their better performance and were assessed and compared to the blank sample. An increase in growth zone diameter is seen in the polymeric nanofibers containing the extracts synthesized on the round coverslip compared to the polymeric solution containing the pre-electrophoretic extract in the bacteria culture medium. In addition, the results of the comparison of the growth zone diameter were similar for polymer nanofibers containing plant extract and gentamicin disc in gram-positive bacteria common in skin infection such as Staphylococcus Aureus and Staphylococcus Epidermidis.

Modeling Epitaxial Layer Growth from Gas Phase for Analysis of Influence of Changing Technological Process with Variation in Growth Zone Heating

In this paper, we analyze the nonstationary heat transfer during growth of epitaxial layers in epitaxy reactors from the gas phase. Based on this analysis, we formulate several recommendations on organization of heating of the growth zone for increasing homogeneity of epitaxial layers. We introduce an analytical approach for analysis of heat transfer during the growth of epitaxial layers from the gas phase. The approach gives a possibility to simultaneously take into account the nonlinearity of heat transfer, as well as changes of their parameters both in space and time.

Gypsum Precipitating From Volcanic Effluent as an Archive of Volcanic Activity

Records of volcanic activity are a key resource in volcano monitoring and hazard mitigation. The time period for which such records are available and the level of detail vary widely among volcanic centers and there is, therefore, a need for supplementary sources of this information. Here, we use growth-zoned gypsum as a mineral archive of the activity of Kawah Ijen volcano in East-Java, Indonesia. Gypsum precipitates where water seeps from the crater lake and hydrothermal system, and it has formed a 100 m long cascading plateau. A 19 cm plateau cross-section was analysed for minor and trace elements using laser-ablation ICP-MS. Absolute ages were assigned to this transect based on 210Pb dating. This 210Pb age model was corrected for variations in the 210Pb0 resulting from fluctuations in the volcanic radon flux by using 84Kr/36Ar and 132Xe/36Ar. The age model indicates that the transect covers a period from 1919 ± 12 to 2008 ± 0.2. Gypsum-fluid partition coefficients (D) permit the gypsum compositions to be converted to the concentrations in the fluid from which each growth zone grew. The D-values also show the compatibility of the elements in the gypsum structure, and identify the LREE, Sr, Pb, Tl, Ni, Co, Cu, Zn, Cd, Sb, Th, and Mo as least susceptible to contamination from rock fragment and mineral inclusions, and therefore as most reliable elements of the gypsum record. Compositional variability in the timeseries correlates with known element behavior in the Kawah Ijen system and shows three element groups: the LREE, Sr, and Pb that represent rock-leaching; Cu, Zn, and Cd, which have previously been linked to immiscible sulfide destabilization in a deep-seated basalt; and Sb, Tl, and As which point to a contribution from the shallow system and evolved magma. Moreover, the gypsum record shows that episodes of unrest and quiescence have a distinct compositional signature in Kawah Ijen seepage fluids, and can be distinguished. Thus, we show that gypsum is a sensitive recorder of volcanic activity and can provide detailed information on the state of the magmatic-hydrothermal system in the past.

Simulation of heat transfer processes during the growth of crystals of the NiFeGaCo alloy

Long crystals of NiFeGaCo alloy with shape memory effect, including magnetically controlled ones, were obtained by the methods of Czochralski and Stepanov. A strong influence on the properties of crystals of dendritic formations, especially noticeable in the initial part of the crystal, has been revealed. In order to optimize the growth experiments, the heat transfer process in the thermal growth zone was simulated. It is shown that the formation of dendrites is due to a change in heat transfer during growth, which leads to an increase in the axial temperature gradient near the crystallization front as the crystal grows. This fits into the framework of the classical concepts of the transition from dendritic growth to normal growth.

Analysis of Financial Distress Using Altman Methode (Z-score) in Bank Umum Milik Negara (BUMN)

The purpose of this study was to analyze bankruptcy using the Altman (Z-Score) method at State-Owned Commercial Banks (BUMN). The results showed that PT. BRI (Persero) Tbk with a condition that is not bankrupt or healthy in 2015 and 2016 the Z-score is 3,404 and 3,341. In 2017 the Z-score is 2,099, in 2018 it is 1,901 and in 2019 it is 2,057 which means it is included in the gray area (it is in growth zone). PT. BNI 46 (Persero) Tbk in 2015 obtained a Z-score of 4.213, meaning that it is not in a state of bankruptcy or health. In 2016 the Z-score was 1.622, 2017 was 1.702, in 2018 it was 1.578 and in 2019 it was 1.388, this means it is included in the gray area (in the growth zone). PT. Bank Mandiri (Persero) Tbk, in 2015 obtained a Z-score of 1,985, in 2016 was 2,074, in 2017 it was 1,914, in 2018 it was 1,818 and in 2019 it was 1,943, this means it is included in a gray area or in a growth zone. PT. BTN (Persero) Tbk in 2015 obtained a Z-score of 1.659, meaning it is included in the gray area (in the growth zone). In 2016 the Z-score was 0.932, 2017 was 0.962, 2018 was 0.835 and 2019 is 0.912, this shows that PT. BTN (Persero) Tbk has the potential to go bankrupt.

Evaluation of the effectiveness of using biodegradable implants based on magnesium oxide compared to titanium alternatives. Experimental study

The issues of improving surgical implants used in treating patients with traumatological and orthopedic profiles continue to remain relevant. The development of a material not inferior in its elastic-strength properties to metal and that does not require further removal remains a reason for studying new samples that are inert during resorption. The purpose of this study was to experimentally explore and compare the bone tissue reaction to the introduction of titanium and magnesium oxide implants, as well as to study the state of magnesium oxide structures at different times after implantation. The material for the study was an implant based on magnesium oxide manufactured by the «MAGNEZIX» company. We operated on 30 rabbits based on the experimental laboratory of the Main Military Clinical Hospital named after academician N.N. Burdenko Russian Defense Ministry. The main group consisted of 10 rabbits, which were injected with a biodegradable screw made of a material based on magnesium oxide. The control group included 10 rabbits, which were injected with a titanium screw. In addition, another group of rabbits was studied. It included 10 young subjects who were injected with an implant based on magnesium oxide into the growth zone. Subjects were removed from the experiment one at a time at various stages. Then X-ray and histological assessment of the paraimplant zone were performed. As a result, the experiment showed that biomaterials based on magnesium oxide are bioinert, do not cause an inflammation reaction or osteolysis of the surrounding tissue, do not lead to the release of gas and the formation of a pathological cavity. During the introduction of magnesium-containing implants to young subjects, no pathological changes in bone tissue, deformities or stunting in the growth of the studied individuals were detected. Based on the obtained experimental data gathered for 6 months, it should be concluded that the material based on magnesium oxide is very promising and suitable for use in traumatology and orthopedics.

Differentiation of the High Night Temperature Response in Leaf Segments of Rice Cultivars with Contrasting Tolerance

High night temperatures (HNT) affect rice yield in the field and induce chlorosis symptoms in leaves in controlled chamber experiments. However, little is known about molecular changes in leaf segments under these conditions. Transcript and metabolite profiling were performed for leaf segments of six rice cultivars with different HNT sensitivity. The metabolite profile of the sheath revealed a lower metabolite abundance compared to segments of the leaf blade. Furthermore, pre-adaptation to stress under control conditions was detected in the sheath, whereas this segment was only slightly affected by HNT. No unique significant transcriptomic changes were observed in the leaf base, including the basal growth zone at HNT conditions. Instead, selected metabolites showed correlations with HNT sensitivity in the base. The middle part and the tip were most highly affected by HNT in sensitive cultivars on the transcriptomic level with higher expression of jasmonic acid signaling related genes, genes encoding enzymes involved in flavonoid metabolism and a gene encoding galactinol synthase. In addition, gene expression of expansins known to improve stress tolerance increased in tolerant and sensitive cultivars. The investigation of the different leaf segments indicated highly segment specific responses to HNT. Molecular key players for HNT sensitivity were identified.

Mental Resilience of Medical Practitioners in Singapore during COVID-19: Survey Results from a Webinar Course on Resilience

Front-line doctors are at high risk of exposure to COVID-19. The mental resilience of general practitioners and their areas of concerns and support required are important during this COVID-19 period. A total of 403 general practitioners attending a webinar on resiliency, hosted by the College of Family Physicians, Singapore, participated in the survey anonymously. Participants provided responses to questions relating to COVID-19 in the domains of Family and friends, Myself, Practice, and Community. Responses are categorized into LEARNING, FEAR, and GROWTH zones. The majority of the doctors reported to be in the GROWTH zone in relation to Family and friends (39%) and Myself (38%) as compared to Practice and Community, aOR = 4.5 (95% CI 3.4 to 5.9), p < 0.001. 34% of the participants reported being in the FEAR zone in relation to Family and friends, aOR = 8.0 (95% CI = 5.6 to 11.2), p < 0.001; at least 81% reported being in the LEARNING zone in relation to Practice and Community, aOR = 7.5 (95% CI = 5.8 to 9.6), p < 0.001, compared to other domains. Supporting and protecting the doctors is important in strategic planning and management of the current pandemic and building preparedness and an effective response towards future crises.

Дослідження остеорегенераційної активності окістя нижньощелепних кісток, уражених кістами різного ґенезу

In response to the prolonged increasing influence of the radicular cyst, there is an adaptive compensatory reaction of the adjacent bone tissue and periosteum located in the area of damage. However, in the available professional literature there is no data on the activity of the marker of osteoregeneration-alkaline phosphatase in the periosteum of the mandible, which is in the growth zone of osteoblastoclastoma. The purpose of the study: to study in a comparative aspect osteoregenerative activity of the periosteum of the mandibular bones affected by radicular cyst and cystic form of osteoblastoclastoma by using the histochemical method. Histochemical studies were performed in 10 patients with large radicular cysts (d>3.0 cm) located on the mandibles – 1st clinical group, and in 9 patients with cystic forms of osteoblastoclastomas, localized on the mandibles - 2nd clinical group. Determination of alkaline phosphatase in periosteal tissues of the mandible was performed by the method of simultaneous azo combination according to Kaplow. Prepared samples of histochemicals were studied under a light microscope, the received images were photographed. Digitized images of histochemicals were analyzed using the computer program ImageJ. The accumulation of alkaline phosphatase in the periosteum of the mandibular areas affected by osteoblastoclastomas is less intense compared to the process of synthesis of this enzyme in the periosteum of the mandible, which is affected by radicular cysts of large size. Osteoregenerative potential of periosteum of mandibular bones affected by radicular cysts is much greater than in the periosteum located in the growth zone of the cystic form of osteoblastoclastoma.