bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity and emendation of the genus Planktoniella (Bacillariophyceae), with descriptions of P. tubulata sp. nov. and P. trifurcata sp. nov
Authors: Yue Fang , Niu Biaobiao , Guo Yaqiong , Lundholm Nina , Li Yang
Published: April 2021

For the first time, LSU and SSU sequences were obtained from four species of the marine planktonic diatom Planktoniella. Samples were collected and cultured from Chinese coastal waters, and morphological observations were made using light and scanning electron microscopy. Combined morphological and DNA sequence data revealed two new species herein described as Planktoniella tubulata and Planktoniella trifurcata. Planktoniella tubulata is characterized by the prominent external tubes of two rimoportulae and the long external tubes of the marginal fultoportulae. The latter are organized regularly in a ring, externally on the mantle, and protrude parallel to the valvar plane. Planktoniella trifurcata is unique in having mucilaginous extensions that usually expand into three lobes, and external extensions of the marginal fultoportulae being either tubes or spines. In the phylogenetic analyses inferred from SSU and LSU sequences, the four analyzed Planktoniella taxa formed a well‐supported monophyletic group. A suite of three characters, mucilage membranes or wings, two marginal rimoportulae, and mantle ribs are diagnostic for Planktoniella. Based on these detailed ultrastructural observations, the description of Planktoniella is emended.
Rise of herbaceous diversity at the southeastern margin of the Tibetan Plateau: First insight from fossils
Authors: Huang Yong‐Jiang , Zhu Hai , Su Tao , Spicer Robert A. , Hu Jin‐Jin , Jia Lin‐Bo , Zhou Zhe‐Kun
Published: April 2021

The Hengduan Mountains region (HMR) on the southeastern Tibetan Plateau, supports a high diversity of herbs, particularly in its subalpine to alpine ecosystems, due to high altitude and cool temperate climate. Current understanding on the formation of such herbaceous richness is based chiefly on molecular phylogenies; however, direct geological evidence is lacking because herbs are rarely preserved as macroscopic fossils. In this study, we present abundant fossil fruits and seeds of herbs from the late Pliocene Heqing Basin in the southern HMR. Our systematic analysis shows the presence of at least 18 species belonging to 11 genera, that is,Ranunculus,Corydalis,Rumex,Polygonum,Chenopodium,Stellaria,Fragaria,Astragalus,Aster,Carex, andSchoenoplectus, of whichPolygonumis most abundant followed byAstragalus. This finding throws the first light from fossil evidence on the rise of herbaceous diversity in the region. We interpret the local assembly of these herbs as resulting from rapid pre‐Pliocene species diversifications of many herbaceous groups in the HMR. As nowadays most of these herbs grow primarily in meadows and a few occur as subaquatic plants, we suggest an open meadow hosting some scattered shrubs in the vicinity of a vegetated wetland in the Heqing Basin during the late Pliocene. This provides the first direct evidence of past treeless open vegetation within the HMR and thus improves our knowledge of vegetation evolution in the region. We suggest that the uplift‐induced climate cooling and monsoon‐associated precipitation seasonality are potentially the key driving forces for the opening of meadow vegetation in the HMR.
Predictors of longer hospitalization of maxillofacial infections‐a 17‐year retrospective study
Authors: Rasteniene Ruta , Vitosyte Milda , Jankauskaite Dainora , Aleksejuniene Jolanta
Published: April 2021

Objectives

To evaluate treatment outcomes in patients with severe maxillofacial infections requiring hospital care during a 17‐year period.

Methods

A retrospective cohort study reviewed 5,465 medical records, and the following data were collected: the reason for infection, locations of inflamed regions, treatment provided, bacteriological findings, and treatment outcomes. Other information included sociodemographic characteristics (age, gender), presence of systemic diseases, and smoking history.

Results

The annual incidence rate of patients with acute maxillofacial infections was 206 ± 19 cases with a male to female ratio 1.4:1.0, a mean hospital stay of 7.9 ± 4.9 days. Older age (>65 years), smoking and systemic diseases (diabetes), the causative tooth (molar), and need for extraoral incision predicted longer hospitalization. Intravenous penicillin was the most common drug prescribed in 50.5% of cases. A total of 132 different microorganisms were identified. The highest microorganism resistance occurred for metronidazole and the highest sensitivity was to clindamycin.

Conclusions

Increased age, smoking, diabetes, causative tooth, and the occurrence of several infected spaces were associated with a longer hospital stay. Streptococcus α haemolyticus was the most common microorganism found in more than 70.0% of cases that were sensitive to intravenous penicillin.
A high stem to leaf ratio reduced rainfall use efficiency under altered rainfall patterns in a semi‐arid grassland in northeast China
Authors: Zhang J. , Gao X. , Zheng X. , Yang Y. , Fan G. , Shi Y. , Wang J. , Mu C.
Published: April 2021

Rainfall use efficiency (RUE) is crucial for understanding the changes in grassland productivity due to variations in future rainfall patterns. Recently, numerous studies have been conducted on the relationship between RUE and the amount of rainfall, but there has been little research on the influence of rainfall distribution and the interactive effect of rainfall amounts and distribution on RUE.

Here, a simulated rainfall experiment was conducted to evaluate the impacts of rainfall amount (average rainfall amount (R0), 334 mm; decreased (R‐) and increased (R+) rainfall amounts, 233 mm and 434 mm, respectively) and dry intervals (comprising 6‐day, 9‐day, 12‐day, 15‐day, 18‐day and 21‐day intervals between rainfall) on productivity and RUE in Leymus chinensis (Trin.) Tzvel., a dominant grass of the Eastern Eurasian Steppe.

Our results showed that (1) for biomass production and RUE, moderate extension of dry intervals was conducive to enhancing total biomass production and RUE. The peak values of total biomass and RUE appeared during the 15‐day interval for R‐, and the 18‐day interval for R0 and R+. (2) For biomass allocation, extension of dry intervals decreased the stem to leaf ratio (S/L) and the root to shoot ratio (R/S). (3) Further, the S/L ratio was significantly negatively correlated with RUE.

These results suggest that variations in rainfall patterns can alter the RUE by changing the S/L ratio, and finally influence biomass production in L. chinensis. These findings have important implications for understanding and predicting the effect of future climate change on productivity in semi‐arid grassland.
Influence of psychological nursing and health education on depression, anxiety and life quality of elderly patients with lung cancer
Authors: Sun Yan , Wang Xiaoyun , Li Na , Bian Junping
Published: April 2021

Background

To explore and analyze the influence of psychological nursing and health education on depression, anxiety and life quality of elderly patients with lung cancer.

Methods

There were 84 elderly patients with lung cancer who were admitted and treated in our hospital since July 2018 till July 2019, serving as the objects of observation. The selected patients were divided into the control group (n = 42) and the observation group in principle of random allocation by computer numbers. Routine care was conducted to the control group, while psychological nursing and health education were implemented to the observation group, so as to compare the improvement effect of depression, anxiety, life quality and compliance on the two groups of patients before/after the two different nursing methods were adopted for intervention.

Results

Hamilton Depression Scale and Hamilton Anxiety Scale scores in the observation group were lower than those in the control group, and the levels of various pulmonary function indicators including degree of blood oxygen saturation, forced expiratory volume in 1 second, forced vital capacity and maximum ventilatory capacity and quality of life scores were significantly improved; compared with the control group, the total compliance of the observation group was significantly increased, and the difference between the two groups was statistically significant (P < 0.05).

Conclusion

The psychological nursing and health education implemented for elderly patients with lung cancer will improve patients' bad mood effectively, enhance life quality and perfect prognosis for patients, maintaining significant value in clinical application.
Nutritional assessment and support during continuous renal replacement therapy
Authors: Ostermann Marlies , Lumlertgul Nuttha , Mehta Ravindra
Published: April 2021

Malnutrition is highly prevalent in patients with acute kidney injury, especially in those receiving renal replacement therapy (RRT). For the assessment of nutritional status, a combination of screening tools, anthropometry, and laboratory parameters is recommended rather than a single test. To avoid underfeeding and overfeeding during RRT, energy expenditure should be measured by indirect calorimetry or calculated using predictive equations. Nitrogen balance should be periodically measured to assess the degree of catabolism and to evaluate protein intake. However, there is limited data for nutritional targets specifically for patients on RRT, such as protein intake. The composition of commercial solutions for continuous renal replacement therapy (CRRT) varies. CRRT itself can be associated with both, nutrient losses into the effluent fluid and caloric gain from dextrose, lactate, and citrate. The role of micronutrient supplementation, and potential use of micronutrient enriched CRRT solutions in this setting is unknown, too. This review provides an overview of existing knowledge and uncertainties related to nutritional aspects in patients on CRRT and emphasizes the need for more research in this area.
Kidney support therapy in the pediatric patient: Unique considerations for a unique population
Authors: Askenazi David , Basu Rajit K.
Published: April 2021

The use of kidney support therapy (KST) for use in managing patients with acute kidney injury (AKI) has expanded greatly in the last several decades. The growing use of KST modalities in children, and now in neonates, has been associated with opportunities for education, clinical research, clinical practice improvements, and outcomes research. A multitude of controversies exist in the field of pediatric KST—many of which are shared by adult critical care nephrology practice. Simultaneously, pediatric KST has led the way to a burgeoning exploration of the importance of fluid overload as it relates to KST initiation and management and also with quality improvement. In this review, we will explore and describe the paradigms contained with pediatric KST used to support children with AKI. In addition to the governing principles related to the mechanics of KST, we will describe the novel aspects of newer support machines and ethical considerations of KST provision. Anticoagulation, dose, and modality will be discussed as well as priming procedures for special considerations. The utilization of KST across pediatric populations represents the next frontier of critical care nephrology.
Impact of C1q fixing donor‐specific antibodies on renal transplant outcome
Authors: Baranwal Ajay Kumar , Goswami Sanjeev , Agarwal Sanjay Kumar , Kaur Gurvinder , Mehra Narinder Kumar
Published: April 2021

Not all anti‐HLA donor‐specific antibodies (HLA‐DSAs) are detrimental to renal allograft. In this context, the C1q complement activating ability of antibodies appears to be an important parameter to distinguish clinically inert versus detrimental DSAs. We evaluated sera of 206 consecutive primary live donor renal transplant recipients before transplant and at post‐operative day 7, 30, 90, 180 and at the time of graft dysfunction for quantifying HLA‐DSAs using single antigen bead assay on a Luminex platform. Patients positive for these antibodies with an MFI >500 were further screened for C1q fixing nature of DSA. Fourteen of the 18 antibody‐positive patients had C1q fixing DSA with MFI value >5000. Only 4 antibody‐positive patients did not have C1q fixing DSA. The MFI values of DSA detected by C1q assay were generally higher at least by 25% than those detected by the conventional IgG‐SAB assay. Twelve of the 14 patients (85.71%) with C1q+ DSA developed antibody‐mediated rejection during the mean follow‐up period of 21.43 ± 8.03 months as compared to none of the four C1q‐negative DSA (85.71% vs 0%; P = .001). These results suggest deleterious effect of C1q+ DSA vis‐à‐vis C1q‐negative DSA on renal allograft.
Feasibility and safety of remdesivir in SARS‐CoV2 infected renal transplant recipients: A retrospective cohort from a developing nation
Authors: Meshram Hari S. , Kute Vivek B. , Patel Himanshu , Banerjee Subho , Navadiya Vijay , Desai Sudeep , Rizvi Syed J , Mishra Vineet , Chauhan Sanshriti
Published: April 2021

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV2) infection has drastically impacted the transplant communities. Remdesivir (RDV) has shown some promising results in coronavirus disease (COVID‐19) albeit with low certainty. Data in kidney transplant recipients (KTR) are still lacking.

Methods

This was a retrospective cohort of 57 moderate to severe COVID‐19 positive KTR in a single center who received RDV as a part of COVID‐19 management. No dose adjustments were done. The outcomes were measured as acute kidney injury (AKI) recovery; liver function tests abnormalities; other side effects; graft loss and death.

Results

The median (inter‐quartile range) age of presentation was 44 (31‐51) years. The duration from onset of symptoms to RDV initiation was 6 (5‐7) days. Thirty‐two (56%) cases received RDV on the day of admission. Forty‐six (81%) cases were on oxygen support upon initiation of RDV. Thirty‐eight (66.6%) cases had acute kidney injury on admission. The median baseline, admission, and 28‐day follow‐up serum creatinine of the cohort were 1.59 (1.1‐2.1), 2.13 (1.3‐3.1), and 1.58 (1.05‐2.1) mg/dl, respectively. A total of 8(14%) cases died in the study with 1 (1.7%) graft loss. All those cases that died were on oxygen therapy at the time of initiation of RDV. No liver function derangements or any other major adverse events with the drug were reported.

Conclusion

RDV therapy is safe and clinically feasible in renal transplant recipients as seen in our cohort. Larger clinical registries and randomized clinical trials should be conducted to further explore the efficacy in transplant recipients.
Study on removal of oxytetracycline hydrochloride in marine aquaculture wastewater by Zn0.75Mn0.75Fe1.5O4/ZnFe2O4/ZnO photocatalyst
Authors: Li Zejun , Yu Xiaocai , Fu Jiayuan , Zhang Yongxia , Xue Bining , Liu Jinghua
Published: April 2021

Photocatalytic degradation of oxytetracycline hydrochloride (OTC‐HCl) in marine aquaculture wastewater and therefore the effects of factors on the effectiveness of photocatalysts are studied in this paper using Zn0.75Mn0.75Fe1.5O4/ZnFe2O4/ZnO under visible light and changing the molar ratio of Zn2+:Fe3+:Mn2+, calcination temperature of catalysts, hydrogen peroxide concentration, dose of catalysts, illumination time of photocatalytic and initial concentration of OTC‐HCl. The degradation of OTC‐HCl in marine aquaculture wastewater was optimized by orthogonal experiment. The best effect exists when the molar ratio of Zn2+:Fe3+:Mn2+ was 10:1:3, the calcination temperature of photocatalyst was 400°C, the concentration of hydrogen peroxide was 0.5 g/L, the dose of catalysts was 0.6 g/L, the illumination time was 2.5 h and the initial concentration of OTC‐HCl was 0.010 g/L. The degradation rate of OTC‐HCl can reach 80.18%. Zn0.75Mn0.75Fe1.5O4/ZnFe2O4/ZnO can effectively degrade the OTC‐HCl in marine aquaculture wastewater under visible light.
Pharmaceuticals and personal care products in aqueous urban environment of western India
Authors: Kachhawaha Akanksha S. , Nagarnaik Pranav M. , Labhasetwar Pawan K. , Banerjee Kaushik
Published: April 2021

Pharmaceuticals and personal care products (PPCPs) are receiving global scientific attention due to their occurrence, persistence and risk to aquatic and terrestrial organisms. In this study, we investigated the occurrence of 19 PPCPs in 6 lakes and River Nag in the city of Nagpur, India. Grab samples were collected and screened by LC–MS/MS. A total of 13 compounds were detected. In the multiple‐site monitoring study, metformin (19–94 µg/L) and triclosan [upto 74.3 µg/L] were identified as the major PPCPs. In the single‐site study (performed for 2 days at 2‐hour interval), a spike was observed in the evening of Day 1, for example, atenolol (0.39–35.9 µg/L), metoprolol (ND‐26.4 µg/L), acetaminophen (1.64–14.2), naproxen (0.5–15.9 µg/L), etc. The maximum number of compounds were detected in Lake Futala (13), followed by Gandhisagar (7), Khindsi (6), Ambazari (4), Koradi (4) and Gorewada (1). Triclosan and methylparaben were the major compounds in lake samples.
Beauty and the Beast: The Value of Teaching Fairy Tales to University Students in the 21st Century
Authors: Beal Jane
Published: April 2021

In this essay, I suggest that fairy tales have particular value for students studying at the university level. Assigning fairy tales allows students to read familiar stories from their childhood and reconsider them from critical perspectives. When teaching a college course on fairy tales, my students and I utilize three essential frameworks for understanding fairy tales, focusing on the psycho-social development and sexual maturation of the human person, feminist critique and the need for gender equality in a patriarchal world, and audience reception and reader responses leading to emotional progress and even spiritual enlightenment. Students primarily familiar with Disney film versions of fairy tales enlarge their understanding of multiple versions of tales, both early modern and contemporary. They become familiar with classic fairy tale writers and collectors, such as Charles Perrault, Madame d’Aulnoy, the Brothers Grimm, Hans Christian Anderson, Oscar Wilde, Andrew Lang, J.R.R. Tolkien, C.S. Lewis, Anne Sexton, Angela Carter, and J.K. Rowling as well as fairy tale scholars like Bruno Bettelheim, Maria Tartar, and Jack Zipes. Their study not only results in a firm grasp of the key aspects of story in general, but in the ability to see connections between the real-world problems of the 21st century – such as poverty, starvation, disease, inequality, child abuse, human trafficking, and abuses of political power, among others – and lessons learned from fairy tales. This essay analyzes “Beauty and the Beast” as a key example of the genre and identifies pedagogical strategies for teaching it.
Chronic stress induced perivascular adipose tissue impairment of aortic function and the therapeutic effect of exercise
Authors: DeVallance Evan R. , Branyan Kayla W. , Olfert I. Mark , Pistilli Emidio E. , Bryner Randall W. , Kelley Eric E. , Frisbee Jefferson C. , Chantler Paul D.
Published: April 2021

New Findings

What is the central question of this study?

Thoracic perivascular adipose tissue (tPVAT) is known to, in part, regulate aortic function: what are the effects of unpredictable chronic mild stress (UCMS) on the tPVAT regulation of aortic function and what is the role of exercise training in alleviating the potential negative actions of UCMS on tPVAT?

What is the main finding and its importance?

UCMS causes tPVAT to disrupt endothelium‐dependent dilatation, increases inflammatory cytokine production and diminishes tPVAT‐adiponectin. Exercise training proved efficacious in preventing tPVAT‐mediated disruption of aortic function. The data support a tPVAT mechanism through which chronic stress negatively impacts vascular health, which adds to our knowledge of how psychological disorders might increase the risk of cardiovascular disease.

Chronic stress is a major risk for cardiovascular disease. Perivascular adipose tissue (PVAT) has been shown to regulate vascular function; however, the impact of chronic stress and the comorbidity of metabolic syndrome (MetS) on thoracic (t)PVAT is unknown. Additionally, aerobic exercise training (AET) is known to combat the pathology of MetS and chronic stress, but the role of tPVAT in these actions is also unknown. Therefore, the purpose of this study was to examine the effects of unpredictable chronic mild stress (UCMS) on the tPVAT regulation of aortic function and the preventative effect of AET. Lean (LZR) and obese (OZR) Zucker rats (16–17 weeks old) were exposed to 8 weeks of UCMS with and without treadmill exercise (AET). In LZR, UCMS impaired aortic endothelium‐dependent dilatation (EDD) (assessedex vivoby wire myography) and aortic stiffness (assessed by elastic modulus) with no change in OZR subject to UCMS. However, both LZR and OZR UCMS tPVAT impaired EDD compared to respective controls. LZR and OZR subject to UCMS had higher oxidative stress production, diminished adiponectin and impaired aortic nitric oxide levels. Divergently, UCMS induced greater inflammatory cytokine production in LZR UCMS tPVAT, but not in OZR UCMS tPVAT. AET prevented the tPVAT impairment of aortic relaxation with UCMS in LZR and OZR. Additionally, AET reduced aortic stiffness in both LZR and OZR. These beneficial effects on tPVAT regulation of the aorta are likely due to AET preservation of adiponectin, reduced oxidative stress and inflammation, and enhanced nitric oxide. UCMS impaired tPVAT‐regulated aortic function in LZR, and augmented MetS‐induced EDD in OZR. Conversely, AET in combination with UCMS largely preserved aortic function and the tPVAT environment, in both groups.
Genetic and epigenetic regulation of skeletal muscle ribosome biogenesis with exercise
Authors: Figueiredo Vandré C. , Wen Yuan , Alkner Björn , Fernandez‐Gonzalo Rodrigo , Norrbom Jessica , Vechetti Ivan J. , Valentino Taylor , Mobley C. Brooks , Zentner Gabriel E. , Peterson Charlotte A. , McCarthy John J. , Murach Kevin A. , von Walden Ferdinand
Published: April 2021

Key points

Ribosome biogenesis and MYC transcription are associated with acute resistance exercise (RE) and are distinct from endurance exercise in human skeletal muscle throughout a 24 h time course of recovery.

A PCR‐based method for relative ribosomal DNA (rDNA) copy number estimation was validated by whole genome sequencing and revealed that rDNA dosage is positively correlated with ribosome biogenesis in response to RE.

Acute RE modifies rDNA methylation patterns in enhancer, intergenic spacer and non‐canonical MYC‐associated regions, but not the promoter.

Myonuclear‐specific rDNA methylation patterns with acute mechanical overload in mice corroborate and expand on rDNA findings with RE in humans.

A genetic predisposition for hypertrophic responsiveness may exist based on rDNA gene dosage.

Ribosomes are the macromolecular engines of protein synthesis. Skeletal muscle ribosome biogenesis is stimulated by exercise, although the contribution of ribosomal DNA (rDNA) copy number and methylation to exercise‐induced rDNA transcription is unclear. To investigate the genetic and epigenetic regulation of ribosome biogenesis with exercise, a time course of skeletal muscle biopsies was obtained from 30 participants (18 men and 12 women; 31 ± 8 years, 25 ± 4 kg m–2) at rest and 30 min, 3 h, 8 h and 24 h after acute endurance (n = 10, 45 min cycling, 70% ) or resistance exercise (n = 10, 4 × 7 × 2 exercises); 10 control participants underwent biopsies without exercise. rDNA transcription and dosage were assessed using quantitative PCR and whole genome sequencing. rDNA promoter methylation was investigated using massARRAY EpiTYPER and global rDNA CpG methylation was assessed using reduced‐representation bisulphite sequencing. Ribosome biogenesis and MYC transcription were associated primarily with resistance but not endurance exercise, indicating preferential up‐regulation during hypertrophic processes. With resistance exercise, ribosome biogenesis was associated with rDNA gene dosage, as well as epigenetic changes in enhancer and non‐canonical MYC‐associated areas in rDNA, but not the promoter. A mouse model of in vivo metabolic RNA labelling and genetic myonuclear fluorescence labelling validated the effects of an acute hypertrophic stimulus on ribosome biogenesis and Myc transcription, and also corroborated rDNA enhancer and Myc‐associated methylation alterations specifically in myonuclei. The present study provides the first information on skeletal muscle genetic and rDNA gene‐wide epigenetic regulation of ribosome biogenesis in response to exercise, revealing novel roles for rDNA dosage and CpG methylation.
Design and Construction of a Statically-Balanced Direct Drive ARM
Authors: Kazerooni H. , Kim S.
Published: April 2021

A statically-balanced direct drive robot manipulator is being constructed at the University of Minnesota for analysis of manufacturing tasks such as deburrlng and grinding when Impedance Control (8, 10, 11) is used to control the robot. This mechanism using a four bar linkage is designed without extra counterweights. As a result of elimination of the gravity forces on the drive system, smaller actuators (and consequently smaller amplifiers) are chosen to guarantee the acceleration of about 5g without overheating the motors. This mechanism results in closed-form solution for Inverse kinematics. The closed-form solutions for dynamic and Inverse kinematic have been derived. High torque, low speed brush-less AC synchronous motors are used to power the robot. The relatively “large” workspace of this configuration is suitable for manufacturing tasks. Graphite epoxy composite material is being used for the construction of the robot links.
The Optimum Kinematic Design of a Spherical Three-Degree-of-Freedom Parallel Manipulator
Authors: Gosselin C. , Angeles J.
Published: April 2021

In this paper, the design of a spherical three-degree-of-freedom parallel manipulator is considered from a kinematic viewpoint. Three different design criteria are established and used to produce designs having optimum characteristics. These criteria are i)symmetry ii)workspace maximization, and iii)isotropy. The associated problems are formulated and their solutions, one of them requiring to resort to a numerical method, are provided. Optimum designs are thereby obtained. A dicussion on singularities is also included.
Orthogonal Arrays and Conjugate Directions for Taguchi-Class Optimization
Authors: Tsai S.-C. , Ragsdell K. M.
Published: April 2021

The work of Genichi Taguchi has recently become a subject of great interest and promise amongst U.S. manufacturing companies. Dr. Taguchi’s philosophy contains two important elements [1] :

1. Quality loss is defined as deviation from target.

2. Quality can only be achieved economically by being designed in.

Dr. Taguchi’s approach employs orthogonal arrays and analysis of variance (ANOVA) tables in place of Taylor-expansion methods[2]. This approach appears to provide an opportunity for greater accuracy and proven convenience for practical engineering problems. This paper reports on a portion of a major effort in the Design Productivity Center to add theoretical justification to the Taguchi approach. In particular we propose a new algorithm which employs orthogonal arrays and conjugate directions in an effort to make Taguchi Methods more effective and theoretically defined.
Application of the Canonical Equations of Motion in Problems of Constrained Multibody Systems With Intermittent Motion
Authors: Lankarani H. M. , Nikravesh P. E.
Published: April 2021

For mechanical systems that undergo intermittent motion, the usual formulation of the equations of motion is not valid over the periods of the discontinuity, and a procedure for balancing the momenta of the system is often performed. A canonical form of the equations of motion is used here as the differential equations of motion. A set of momentum balance-impulse equations are derived in terms of the system total momenta by explicitly integrating the canonical equations. The method shows to be stable while numerically integrating the canonical equations, and efficient while solving the momentum balance-impulse equations. Examples are provided to illustrate the validity of the method.
Parallel Processing for Real-Time Dynamic System Simulation
Authors: Hwang R. S. , Bae D.-S. , Haug E. J. , Kuhl J. G.
Published: April 2021

A parallel processing algorithm based on the recursive dynamics formulation presented in a companion paper [1] is developed for multiprocessor implementation. Lagrange multipliers associated with cut-joint constraints for closed loop systems are eliminated systematically, resulting to a minimal set of equations of motion. Concurrent generation of the system inertia matrix and the generalized force vector is exploited. A new computational structure for dynamic analysis is proposed for real-time parallel processing. Real-time simulation of a vehicle is performed to illustrate efficiency and effectiveness of the algorithm, even for interactive man-in-the-loop simulation.
Transformative climate adaptation in the United States: Trends and prospects
Authors: Shi Linda , Moser Susanne
Published: April 2021

Adapting to the new normal

Successfully responding to the impacts of climate change will be a challenge for many communities, especially cities. Considering the situation in the United States, Shi and Moser examine how stakeholders can help to build urban resilience even in the absence of federal leadership. They discuss how local and state governments, private industry, and civil society can engage to adapt to the extreme weather events and other consequences of changing climate that are expected in the future. Preparing for these looming issues requires coherent, cohesive, and collective responses across all scales and sectors of society.

Science
, abc8054, this issue p.
eabc8054
A third purine biosynthetic pathway encoded by aminoadenine-based viral DNA genomes
Authors: Sleiman Dona , Garcia Pierre Simon , Lagune Marion , Loc’h Jerome , Haouz Ahmed , Taib Najwa , Röthlisberger Pascal , Gribaldo Simonetta , Marlière Philippe , Kaminski Pierre Alexandre
Published: April 2021

Biosynthesis and replication, from A to Z

Four nucleobases. adenine (A), cytosine (C), guanine (G), and thymine (T), are usually thought to be invariable in DNA. In bacterial viruses, however, each of the DNA bases have variations that help them to escape degradation by bacterial restriction enzymes. In the genome of cyanophage S-2L, A is completely replaced by diaminopurine (Z), which forms three hydrogen bonds with T and thus creates non–Watson-Crick base pairing in the DNA of this virus (see the Perspective by Grome and Isaacs). Zhou
et al.
and Sleiman
et al.
determined the biochemical pathway that produces Z, which revealed more Z genomes in viruses hosted in bacteria distributed widely in the environment and phylogeny. Pezo
et al.
identified a DNA polymerase that incorporates Z into DNA while rejecting A. These findings enrich our understanding of biodiversity and expand the genetic palette for synthetic biology.

Science
, this issue p.
512
,
516
,
520
; see also p.
460
How SARS-CoV-2 first adapted in humans
Authors: Choe Hyeryun , Farzan Michael
Published: April 2021

An early spike protein mutation promotes transmission and will shape the next vaccines
Feasibility of cardiopulmonary exercise testing in interstitial lung disease: the PETFIB study
Authors: Tomlinson Owen , Duckworth Anna , Markham Laura , Wollerton Rebecca , Knight Bridget , Spiers Alexander , Gibbons Michael , Williams Craig , Scotton Chris
Published: April 2021

Introduction

Cardiopulmonary exercise testing (CPET) provides a series of biomarkers, such as peak oxygen uptake, which could assess the development of disease status in interstitial lung disease (ILD). However, despite use in research and clinical settings, the feasibility of CPET in this patient group has yet to be established.

Methods

Twenty-six patients with ILD (19 male) were recruited to this study. Following screening for contraindications to maximal exercise, participants underwent an incremental CPET to volitional exhaustion. Feasibility of CPET was assessed by the implementation, practicality, acceptability and demand, thus providing clinical-driven and patient-driven information on this testing procedure.

Results

Of the 26 recruited participants, 24 successfully completed at least one CPET, with 67/78 prospective tests being completed. Contraindications included hypertension, low resting oxygen saturation and recent pulmonary embolism. Of the CPETs undertaken, 63% successfully reached volitional exhaustion, with 31% being terminated early by clinicians due to excessive desaturation. Quantitative and qualitative feedback from participants revealed a positive experience of CPET and desire for it to be included as a future monitoring tool.

Conclusion

CPET is feasible in patients with ILD. Identification of common clinical contraindications, and understanding of patient perspectives will allow for effective design of future studies utilising CPET as a monitoring procedure.
Anxiety and depression severity in neuropsychiatric SLE are associated with perfusion and functional connectivity changes of the frontolimbic neural circuit: a resting-state f(unctional) MRI study
Authors: Antypa Despina , Simos Nicholas J , Kavroulakis Eleftherios , Bertsias George , Fanouriakis Antonis , Sidiropoulos Prodromos , Boumpas Dimitrios , Papadaki Efrosini
Published: April 2021

Objective

To examine the hypothesis that perfusion and functional connectivity disturbances in brain areas implicated in emotional processing are linked to emotion-related symptoms in neuropsychiatric SLE (NPSLE).

Methods

Resting-state fMRI (rs-fMRI) was performed and anxiety and/or depression symptoms were assessed in 32 patients with NPSLE and 18 healthy controls (HC). Whole-brain time-shift analysis (TSA) maps, voxel-wise global connectivity (assessed through intrinsic connectivity contrast (ICC)) and within-network connectivity were estimated and submitted to one-sample t-tests. Subgroup differences (high vs low anxiety and high vs low depression symptoms) were assessed using independent-samples t-tests. In the total group, associations between anxiety (controlling for depression) or depression symptoms (controlling for anxiety) and regional TSA or ICC metrics were also assessed.

Results

Elevated anxiety symptoms in patients with NPSLE were distinctly associated with relatively faster haemodynamic response (haemodynamic lead) in the right amygdala, relatively lower intrinsic connectivity of orbital dlPFC, and relatively lower bidirectional connectivity between dlPFC and vmPFC combined with relatively higher bidirectional connectivity between ACC and amygdala. Elevated depression symptoms in patients with NPSLE were distinctly associated with haemodynamic lead in vmPFC regions in both hemispheres (lateral and medial orbitofrontal cortex) combined with relatively lower intrinsic connectivity in the right medial orbitofrontal cortex. These measures failed to account for self-rated, milder depression symptoms in the HC group.

Conclusion

By using rs-fMRI, altered perfusion dynamics and functional connectivity was found in limbic and prefrontal brain regions in patients with NPSLE with severe anxiety and depression symptoms. Although these changes could not be directly attributed to NPSLE pathology, results offer new insights on the pathophysiological substrate of psychoemotional symptomatology in patients with lupus, which may assist its clinical diagnosis and treatment.
Long-term stability in the volume of Atlantic Puffin (Fratercula arctica) eggs in the western North Atlantic
Authors: Lefort Kyle J. , Major Heather L. , Bond Alexander L. , Diamond Antony W. , Jones Ian L. , Montevecchi William A. , Provencher Jennifer F. , Robertson Gregory J.
Published: April 2021

In the eastern North Atlantic, declines in the volume of Atlantic Puffin (Fratercula arctica (Linnaeus, 1758)) eggs have been associated with shifts in the marine ecosystem, such as changes in the abundance of forage fishes and increasing sea-surface temperatures. In the western North Atlantic, where similar shifts in oceanographic conditions and changes in the abundance of forage fishes have presumably occurred, trends in the volume of Atlantic Puffin eggs remain unknown. In this study, we investigate Atlantic Puffin egg volume in the western North Atlantic. We compiled 140 years (1877–2016) of egg volume measurements (n = 1805) and used general additive mixed-effects models to investigate temporal trends and regional variation. Our findings indicate that Atlantic Puffin egg volume differs regionally but has remained unchanged temporally in the western North Atlantic since at least the 1980s.
Flexibility of nuptial colouration in a unique ecotype of threespine stickleback (Gasterosteus aculeatus)
Authors: Corney Rachel H. , Haley Anne L. , Weir Laura K.
Published: April 2021

Nuptial colouration in animals may serve as a signal of competitor and (or) mate quality during breeding. In many temperate fishes, nuptial colouration develops during discrete breeding seasons and is a target of sexual selection. We examine nuptial colouration and behaviour of a unique ecotype of threespine stickleback (Gasterosteus aculeatus Linnaeus, 1758), wherein males turn from dull brown-grey to pearlescent white during the breeding season. The main goal of this work was to determine the relative role of white colouration in intersexual competition and mate choice. In a combination of field and laboratory work, we found that males are brightest white when engaging in courtship activities in the presence of a female; this indicates that white colouration may be primarily related to enhancing signalling during mate attraction. White colouration intensity increased as the breeding season progressed and may be related to an influx of conspecifics. Colour change from cryptic grey to bright white occurred rapidly (<90 s) and may be deployed to enhance behavioural signals. We conclude that bright white colouration in the white ecotype is a potential signal of mate quality and may have evolved from a previously existing capacity for colour plasticity in common threespine stickleback.
THE EFFECTS OF NOZZLE NUMBER AND OUTLET GEOMETRY ON GRINDING PROCESS WITH MINIMUM QUANTITY COOLING (MQC) BY NANOFLUID
Authors: ABIYARI HOOMAN , ABOOTORABI MOHAMMAD MAHDI
Published: April 2021

Machining with minimum quantity lubrication (MQL) or minimum quantity cooling (MQC) as a subset of green machining is a process in which small volume fluid of high lubrication and cooling properties alongside high pressure air is used in the material removal process. The heat generated in the grinding process has a great impact upon the workpiece quality. Serving lubrication and heat transfer functions, cutting fluids have an essential role in reducing the temperature and thus improving the process of grinding. In this research, nanofluid made of graphene nanoparticles in water-based fluid as a cutting fluid of high heat transfer is utilized to investigate the effects of nozzle number and nozzle geometry of the MQC system on the cutting temperature and surface roughness of the workpiece. The effect of geometry and number of nozzles on grinding with MQC has not been studied so far. The study findings show that the nozzle outlet cross-section of rectangular, compared to circular, decreases the surface roughness and temperature by 30% and 36%, respectively. Moreover, compared to the single nozzle, the use of three nozzles results in a decrease of 19% and 31.7% in the surface roughness and temperature. Under the same machining conditions, the MQC method by 0.15[Formula: see text]wt.% nanofluid of graphene in water using a rectangular nozzle outlet of 1.2[Formula: see text]mm width makes surface roughness and temperature reduced by 67.2% and 48.3% compared to the dry condition, whereas decreased by 13.4% and 8.8% compared to the wet method, respectively.
ANALYSIS OF DENTAL CARIES IN THE PERMANENT FIRST MOLARS AND RELATED FACTORS WITH CHILDREN AGED 10–12 YEARS IN SOUTHERN CHINA
Authors: YAN YIXUAN , HUANG QUN , YAN FENGZHI
Published: April 2021

In order to investigate and analyze the caries status of permanent first molars (PFMs) in children aged 10 to 12 years in Southern China and to analyze the related factors, from January to August 2019, a multi-stage, stratified, cluster, and random sampling method had been used to select 6208 children from 22 schools in Guangzhou city for oral health examinations and questionnaires. The total caries rate of the PFMs was 39.40%, total DMFT score was [Formula: see text], the filling rate of caries was 3.38%, and the rate of fissure sealant was 5.89%. The percentage of PFM caries was statistically significant between female and boys, urban and rural areas, only-children and non-only children, and between ethnic minorities and Han ethnic groups ([Formula: see text]). The difference between urban and rural areas was statistically significant ([Formula: see text]). Multivariate logistic regression analysis showed that the number of daily toothbrushes, the number of desserts eaten, milk drinking before bedtime, being the only-child, and the parents’ level of education were the independents influencing the factors of for developing dental caries. The incidence of dental caries in the PFMs of children aged 10–12 years in Southern China is high, and the rate of fissure sealant and the rate of dental fillings are low. There are a lot of differences between urban and rural areas, where children’s oral health knowledge is poor, and poor oral hygiene behaviors and dietary habits exist.
Hybrid Image-based Rendering for Free-view Synthesis
Authors: Prakash Siddhant , Leimkühler Thomas , Rodriguez Simon , Drettakis George
Published: April 2021

Image-based rendering (IBR) provides a rich toolset for free-viewpoint navigation in captured scenes. Many methods exist, usually with an emphasis either on image quality or rendering speed. In this paper we identify common IBR artifacts and combine the strengths of different algorithms to strike a good balance in the speed/quality tradeoff. First, we address the problem of visible color seams that arise from blending casually-captured input images by explicitly treating view-dependent effects. Second, we compensate for geometric reconstruction errors by refining per-view information using a novel clustering and filtering approach. Finally, we devise a practical hybrid IBR algorithm, which locally identifies and utilizes the rendering method best suited for an image region while retaining interactive rates. We compare our method against classical and modern (neural) approaches in indoor and outdoor scenes and demonstrate superiority in quality and/or speed.
Tidal Disruption Events
Authors: Gezari Suvi
Published: April 2021

The concept of stars being tidally ripped apart and consumed by a massive black hole (MBH) lurking in the center of a galaxy first captivated theorists in the late 1970s. The observational evidence for these rare but illuminating phenomena for probing otherwise dormant MBHs first emerged in archival searches of the soft X-ray ROSAT All-Sky Survey in the 1990s, but has recently accelerated with the increasing survey power in the optical time domain, with tidal disruption events (TDEs) now regarded as a class of optical nuclear transients with distinct spectroscopic features. Multiwavelength observations of TDEs have revealed panchromatic emission, probing a wide range of scales, from the innermost regions of the accretion flow to the surrounding circumnuclear medium. I review the current census of 56 TDEs reported in the literature, and their observed properties can be summarized as follows: ▪  The optical light curves follow a power-law decline from peak that scales with the inferred central black hole mass as expected for the fallback rate of the stellar debris, but the rise time does not. ▪  The UV-optical and soft X-ray thermal emission come from different spatial scales, and their intensity ratio has a large dynamic range and is highly variable, providing important clues as to what is powering the two components. ▪  They can be grouped into three spectral classes, and those with Bowen fluorescence line emission show a preference for a hotter and more compact line-emitting region, whereas those with only Heii emission lines are the rarest class.
Forests and Sustainable Development in the Brazilian Amazon: History, Trends, and Future Prospects
Authors: Garrett Rachael D. , Cammelli Federico , Ferreira Joice , Levy Samuel A. , Valentim Judson , Vieira Ima
Published: April 2021

Ongoing deforestation in the Brazilian Amazon is the outcome of an explicit federal project to occupy, integrate, and “modernize” the region. Although there have been isolated periods of deforestation control, most recently between 2004 and 2012, the overall trajectory of the region since the colonial period has been one of forest loss and degradation. Addressing this challenge is especially urgent in the context of adverse climate-ecology feedbacks and tipping points. Here we describe the trends and outcomes of deforestation and degradation in the Amazon. We then highlight how historical development paradigms and policies have helped to cement the land use activities and structural lock-ins that underpin deforestation and degradation. We emphasize how the grounds for establishing a more sustainable economy in the Amazon were never consolidated, leading to a situation where forest conservation and development remain dependent on external programs—punitive measures against deforestation and fire and public social programs. This situation makes progress toward a forest transition(arresting forest loss and degradation and restoring forest landscapes) highly vulnerable to changes in political leadership, private sector engagement, and global market signals. After summarizing these challenges, we present a suite of measures that collectively could be transformational to helping overcome destructive path dependencies in the region. These include innovations in agricultural management, improved forest governance through landscape approaches, developing a local forest economy, sustainable peri-urbanization, and the empowerment of women and youth. These initiatives must be inclusive and equitable, enabling the participation and empowerment of local communities, particularly indigenous groups who have faced numerous historical injustices and are increasingly under threat by current politics.
How Cortical Circuits Implement Cortical Computations: Mouse Visual Cortex as a Model
Authors: Niell Cristopher M. , Scanziani Massimo
Published: April 2021

The mouse, as a model organism to study the brain, gives us unprecedented experimental access to the mammalian cerebral cortex. By determining the cortex's cellular composition, revealing the interaction between its different components, and systematically perturbing these components, we are obtaining mechanistic insight into some of the most basic properties of cortical function. In this review, we describe recent advances in our understanding of how circuits of cortical neurons implement computations, as revealed by the study of mouse primary visual cortex. Further, we discuss how studying the mouse has broadened our understanding of the range of computations performed by visual cortex. Finally, we address how future approaches will fulfill the promise of the mouse in elucidating fundamental operations of cortex.