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A chatter mark is a result of irregular vibration that affects the milling process, which results in poor surface finish, reduced work quality, machine impairment, and high production cost. This work presents an active feedback controller design using a new response matrix to suppress the free vibration in the milling process. The proposed controller considers feed rate, tooth passing frequency, and time-varying dynamic milling force coefficients. A milling experiment verifies the effect of the proposed method. The method provides a reliable way of tackling chatter vibration in an industrial process. The procedure is technically and economically beneficial. [ABSTRACT FROM AUTHOR]

Climate change will have various impacts on the survival and development of species, and it is important to explore whether plants can adapt to future climate conditions. Dipteronia dyeriana is an endangered species with a narrow distribution in Yunnan, characterized by a small population size. However, studies on its current distribution and the impact of climate change on its future survival and distribution are very limited. In this study, the current and future (2050 and 2090) potential habitats under the SSP1-2.6, SSP3-7.0, and SSP5-8.5 scenarios were predicted using both maximum entropy (MaxEnt) and random forest (RF) models based on the current range points of D. dyeriana, soil, topographical, land cover, and climate data. The results showed that the RF model demonstrated significantly higher AUC, TSS, and Kappa scores than the MaxEnt model, suggesting high accuracy of the RF model. Isothermality (bio_3), minimum temperature of the coldest month (bio_6), and annual precipitation (bio_12) are the main environmental factors affecting the distribution of D. dyeriana. At present, the high suitability area of D. dyeriana is mainly concentrated in the eastern part of Yunnan Province and part of southern Tibet, covering an area of 3.53 × 104 km2. Under future climate change scenarios, the total area suitable for D. dyeriana is expected to increase. Although, the highly suitable area has a tendency to decrease. With regards to land use, more than 77.53% of the suitable land area (29.67 × 104 km2) could be used for D. dyeriana planting under different SSP scenarios. In 2090, the centroid shifts of the two models exhibit a consistent trend. Under the SSP1-2.6 scenario, the centroids transfer to the southeast. However, under the SSP3-7.0 and SSP5-8.5 scenarios, the centroids of high suitability areas migrate toward the northwest. In summary, this study enhances our understanding of the influence of climate change on the geographic range of D. dyeriana and provides essential theoretical backing for efforts in its conservation and cultivation. [ABSTRACT FROM AUTHOR]

Abstract Four new deep ultraviolet (DUV) borates Li 7 Na 2 KRb 2 B 12 O 24 , Li 7.35 Na 2.36 K 1.50 Cs 0.78 B 12 O 24 , Li 6.97 Na 2.63 K 1.24 Cs 1.15 B 12 O 24 , and Li 7.27 Na 2.67 Rb 2.06 B 12 O 24 have been produced by high temperature solution method in open air. The structural analysis suggests that they all crystallize in the same trigonal space group R 3 ¯ (No. 148), and possess the identical isolated B 12 O 24 groups. Structural comparison among alkali-metal borates with B n O 2n in their chemical formulas have been discussed. In addition, infrared spectra were used to verify their structural validity. Furthermore, the UV–Vis–NIR diffuse reflectance spectra reveal that they exhibit short cutoff edges below 180 nm (6.88 eV). The first-principles theoretical studies carried out to increase the understanding of electronic structure and linear optical property. Graphical abstract Four new borates Li 7 Na 2 KRb 2 B 12 O 24 , Li 7.35 Na 2.36 K 1.50 Cs 0.78 B 12 O 24 , Li 6.97 Na 2.63 K 1.24 Cs 1.15 B 12 O 24 , and Li 7.27 Na 2.67 Rb 2.06 B 12 O 24 have been obtained. All of them exhibit isolated B 12 O 24 groups and short UV cut-off edges below 180 nm (6.88 eV). Image 1 Highlights • Four new compounds were synthesized, they all exhibit short cutoff edge below 180 nm. • Structural comparisons among alkali-metal borates with B n O 2n in their chemical formulas offered to foster the structural understanding. • Band structures and density of states for Li 7 Na 2 KRb 2 B 12 O 24 have been calculated firstly. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Synchronous bilateral adrenalectomy by midline incision: A reliable method for treatment of hypercortisolism" by S. A. Tabatabaee and colleagues, in the 2011 issue.

The aim of the research: the article deals with study of modern Dagestan city linguistic landscape. The relevance of the research: the relevance of the chosen topic is explained by the need for a synchronous description and analysis of toponymic, cultural-historical, linguistic, cultural, ethnolinguistic, and sociolinguistic traditions and representations of a complex and multi-level toponymic system on the example of one Dagestan city - the capital of the Republic - Makhachkala. It is a unique phenomenon of Russian and Dagestan linguistic cultures mix, which united into a single one. Research methods: the scientific research paper considers the basic principles of urbanonyms' nomination, the most frequent word-building patterns of both official and unofficial names of urban objects and microtoponyms of present and past. The specifics of the post-Soviet Dagestan city linguistic landscape have been revealed as its shows socio-political, economic, cultural and ideological tendencies of different periods of Russian history. Toponyms are considered not only from the perspective of structural, semantic and functional aspects, but also from the point of cognition. Special attention is paid to ergonyms as a significant part of urbanization. The conditions its creation and successful functioning are indicated. Results: the analysis of the linguistic landscape of Makhachkala has revealed universal and specific mechanisms of toponyms composition, reflecting the peculiarities of regional mentality. This is a diverse, often inconsistent linguistic practice of Russian, English and Dagestan languages usage, which shows us the multi-language and socio-cultural chronotope of the city. The area of the pragmatics of languages functioning is determined by the socio-political and economic factors, which influence on the initially polylingual Makhachkala. Significance of the research: the further prospects of research are observation and changes analysis of modern Dagestan city in the linguistic landscape of the modern Dagestan city. It will allow us to understand more deeply the sociolinguistic processes in the polyethnic Russian society. [ABSTRACT FROM AUTHOR]

Entropy creation by a blood-hybrid nanofluid flow with gold-tantalum nanoparticles in a tilted cylindrical artery with composite stenosis under the influence of Joule heating, body acceleration, and thermal radiation is the focus of this research. Using the Sisko fluid model, the non-Newtonian behaviour of blood is investigated. The finite difference (FD) approach is used to solve the equations of motion and entropy for a system subject to certain constraints. The optimal heat transfer rate with respect to radiation, Hartmann number, and nanoparticle volume fraction is calculated using a response surface technique and sensitivity analysis. The impacts of significant parameters such as Hartmann number, angle parameter, nanoparticle volume fraction, body acceleration amplitude, radiation, and Reynolds number on the velocity, temperature, entropy generation, flow rate, shear stress of wall, and heat transfer rate are exhibited via the graphs and tables. Present results disclose that the flow rate profile increase by improving the Womersley number and the opposite nature is noticed in nanoparticle volume fraction. The total entropy generation reduces by improving radiation. The Hartmann number expose a positive sensitivity for all level of nanoparticle volume fraction. The sensitivity analysis revealed that the radiation and nanoparticle volume fraction showed a negative sensitivity for all magnetic field levels. It is seen that the presence of hybrid nanoparticles in the bloodstream leads to a more substantial reduction in the axial velocity of blood compared to Sisko blood. An increase in the volume fraction results in a noticeable decrease in the volumetric flow rate in the axial direction, while higher values of infinite shear rate viscosity lead to a significant reduction in the magnitude of the blood flow pattern. The blood temperature exhibits a linear increase with respect to the volume fraction of hybrid nanoparticles. Specifically, utilizing a hybrid nanofluid with a volume fraction of 3% leads to a 2.01316% higher temperature compared to the base fluid (blood). Similarly, a 5% volume fraction corresponds to a temperature increase of 3.45093%. [ABSTRACT FROM AUTHOR]

Species of Rheum have high medicinal value, with the center of diversity in the Qinghai–Tibet Plateau (QTP) and adjacent regions. However, phylogenetic relationships of Rheum are still unclear due to fragment markers providing insufficient informative loci. Here, we sequenced and annotated plastomes of nine Rheum species, and compared the genome structure among the novel nine species along with three published species. Comparative analyses revealed that plastomes of Rheum share a relatively conserved structure. Five highly divergent regions (accD, ccsA, matK, ndhF, and ndhH) can be used as valuable molecular markers for further species delimitation and population genetic studies. Twenty‐two accessions representing 17 species were used for phylogenetic analysis, which generated a robust phylogenetic tree and revealed two major clades within Rheum. Phylogenetic results showed that glasshouse structures and cushions of Rheum are results of parallel evolution during adaptation to similar environments. Inconsistent tree topology between concatenated and coalescent methods was detected, implying that incomplete lineage sorting and hybridization may have occurred in the evolutionary history of Rheum. Divergence time estimation based on two fossil calibrations and three secondary calibrations revealed a Miocene to middle Oligocene origin of Rheum. Our study provides valuable genomic resources for the medicinally important genus Rheum, while gaining helpful insights into its systematics and evolution. [ABSTRACT FROM AUTHOR]

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies. Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients). A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality. Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies. NCT04354701 • Among 4966 patients with COVID-19 and a history of or active cancer, 58% were hospitalized and 14% died within 30 days. • Older age, male sex, obesity, comorbidities, non-Hispanic black race, and Hispanic ethnicity were associated with higher COVID-19 severity. • Worse performance status, hematologic malignancy, and recent cytotoxic chemotherapy were associated with more severe COVID-19. • Low or high absolute lymphocyte count, high absolute neutrophil count, low platelets, abnormal creatinine, troponin, lactate dehydrogenase, or C-reactive protein were associated with more severe COVID-19. • Specific anticancer therapies were associated with high 30-day all-cause mortality. [ABSTRACT FROM AUTHOR]

Background Despite level 1 evidence demonstrating the equivalence of single-fraction radiotherapy (sfrt) and multiple-fraction radiotherapy (mfrt) for the palliation of painful bone metastases, sfrt remains underused. In 2015, to encourage the sustainable use of palliative radiation oncology resources, CancerCare Manitoba disseminated, to each radiation oncologist in Manitoba, guidelines from Choosing Wisely Canada (cwc) that recommend sfrt. We assessed whether dissemination of the guidelines influenced sfrt use in Manitoba in 2016, and we identified factors associated with mfrt. Methods All patients treated with palliative radiotherapy for bone metastasis in Manitoba from 1 January 2016 to 31 December 2016 were identified from the provincial radiotherapy database. Patient, treatment, and disease characteristics were extracted from the electronic medical record and tabulated by fractionation schedule. Univariable and multivariable logistic regression analyses were performed to identify risk factors associated with mfrt. Results In 2016, 807 patients (mean age: 70 years; range: 35-96 years) received palliative radiotherapy for bone metastasis, with 69% of the patients having uncomplicated bone metastasis. The most common primary malignancies were prostate (27.1%), lung (20.6%), and breast cancer (15.9%). In 62% of cases, mfrt was used--a proportion that was unchanged from 2015. On multivariable analysis, a gastrointestinal [odds ratio (or): 5.3] or lung primary (or: 3.3), complicated bone metastasis (or: 4.3), and treatment at a subsidiary site (or: 4.4) increased the odds of mfrt use. Conclusions Dissemination of cwc recommendations alone did not increase sfrt use by radiation oncologists in 2016. A more comprehensive knowledge translation effort is therefore warranted and is now underway to encourage increased uptake of sfrt in Manitoba. [ABSTRACT FROM AUTHOR]