bluuebunny/crossref_metadata_2025 huggingface dataset:
Bi-chromaticity and tunability of random lasing in mesoporous silica SBA16 doped with rhodamine B
Authors: Melo Leandro A , Prado Marcus V A , De Vicente Fábio S , Moreno Leandro X , Rodrigues Jr José Joatan , Alencar Márcio A R C
Published: May 2022

The random laser emission from ordered mesoporous silica SBA16 doped with rhodamine B (RB) organic dye was investigated. Powdered SBA16 with 16 nm average pore diameter have been synthesized and doped with five different concentrations of the organic dye. Typical incoherent feedback random laser behavior was observed. The bi-chromatic emission was characterized for the sample with the highest dye concentration. Tunable random laser emissions from 578 to 618 nm were obtained depending on the excitation laser spot diameter and the rhodamine-B load. The results indicate that mesoporous RB-doped SBA16 is a promising material for the development of solid-state random lasers.
Symmetric and antisymmetric vector solitons for the fractional quadric-cubic coupled nonlinear Schrödinger equation
Authors: Xu Jia-Zhen , Cao Qi-Hao , Dai Chao-Qing
Published: May 2022

The fractional quadric-cubic coupled nonlinear Schrödinger equation is concerned, and vector symmetric and antisymmetric soliton solutions are obtained by the square operator method. The relationship between the Lévy index and the amplitudes of vector symmetric and antisymmetric solitons is investigated. Two components of vector symmetric and antisymmetric solitons show a positive and negative trend with the Lévy index, respectively. The stability intervals of these solitons and the propagation constants corresponding to the maximum and minimum instability growth rates are studied. Results indicate that vector symmetric solitons are more stable and have better interference resistance than vector antisymmetric solitons.
Passive double pendulum in the wake of a cylinder forced to rotate emulates a cyclic human walking gait
Authors: Carleton Adrian G , Sup Frank C , Modarres-Sadeghi Yahya
Published: May 2022

The goal of this work is to present a method based on fluid–structure interactions to enforce a desired trajectory on a passive double pendulum. In our experiments, the passive double pendulum represents human thigh and shank segments, and the interaction between the fluid and the structure comes from a hydrofoil attached to the double pendulum and interacting with the vortices that are shed from a cylinder placed upstream. When a cylinder is placed in flow, vortices are shed in the wake of the cylinder. When the cylinder is forced to rotate periodically, the frequency of the vortices that are shed in its wake can be controlled by controlling the frequency of cylinder’s rotation. These vortices exert periodic forces on any structure placed in the wake of this cylinder. In our system, we place a double pendulum fitted with a hydrofoil at its distal end in the wake of a rotating cylinder. The vortices exert periodic forces on this hydrofoil which then forces the double pendulum to oscillate. We control the cylinder to rotate periodically, and measure the displacement of the double pendulum. By comparing the joint positions of the double pendulum with those of human hip, knee and ankle joint positions during walking, we show how the system is able to generate a human walking gait cycle on the double pendulum only using the interactions between the vortices and the hydrofoil.
Mitigating ozone damage to ecosystem productivity through sectoral and regional emission controls: a case study in the Yangtze River Delta, China
Authors: Lei Yadong , Yue Xu , Wang Zhili , Liao Hong , Zhang Lin , Tian Chenguang , Zhou Hao , Zhong Junting , Guo Lifeng , Che Huizheng , Zhang Xiaoye
Published: May 2022

The land ecosystems of China are estimated to provide an important sink for the increased atmospheric carbon dioxide (CO2), but are undermined by severe ozone (O3) pollution. Mitigation of O3 damage to ecosystems remains a challenge considering that O3 precursors are emitted from a wide range of anthropogenic sectors and O3 formations are also affected by regional transport. Here, we combine chemical transport and dynamic vegetation models to quantify the benefits of sectoral and regional emission controls for the recovery of gross primary productivity (GPP) in the Yangtze River Delta (YRD). For sectoral emission controls, the largest mitigation of O3 damage to GPP in YRD by 3.1 ± 0.4 and 2.2 ± 0.2 Gg[C] d−1 with 50% reductions in the emissions from industry and transportation sectors, respectively. For regional emission controls, reducing 50% anthropogenic emissions outside YRD can mitigate GPP losses by 18.6 ± 3.5 Gg[C] d−1, larger than the recovery of 10.1 ± 1.6 Gg[C] d−1 by the 50% reductions of anthropogenic emissions within YRD. Moreover, summer months, especially July are the best period for GPP recovery from anthropogenic emission controls. Our results highlight the importance of sectoral and regional emission controls to mitigate O3 damage to ecosystem productivities in YRD.
Mixed dispersion nonlinear Schrödinger equation in higher dimensions: theoretical analysis and numerical computations
Authors: Stefanov Atanas , Tsolias Georgios A , Cuevas-Maraver Jesús , Kevrekidis Panayotis G
Published: May 2022

In the present work we provide a characterization of the ground states of a higher-dimensional quadratic-quartic model of the nonlinear Schrödinger class with a combination of a focusing biharmonic operator with either an isotropic or an anisotropic defocusing Laplacian operator (at the linear level) and power-law nonlinearity. Examining principally the prototypical example of dimension d = 2, we find that instability arises beyond a certain threshold coefficient of the Laplacian between the cubic and quintic cases, while all solutions are stable for powers below the cubic. Above the quintic, and up to a critical nonlinearity exponent p, there exists a progressively narrowing range of stable frequencies. Finally, above the critical p all solutions are unstable. The picture is rather similar in the anisotropic case, with the difference that even before the cubic case, the numerical computations suggest an interval of unstable frequencies. Our analysis generalizes the relevant observations for arbitrary combinations of Laplacian prefactor b and nonlinearity power p.
Determination of amoxicillin trihydrate impurities 4-hydroxyphenylglycine (4-HPG) and 6-Aminopenicylanic acid (6-APA) by means of ultraviolet spectroscopy
Authors: Ergin M F , Yasa Hasniye
Published: May 2022

Amoxicillin is one of the broad-spectrumβ-lactam antibiotics widely used in the treatment of many diseases. It is inevitable that 4-hydroxyphenylglycine (4-HPG) and 6-Aminopenicylanic acid (6-APA), which are used during the production of this antibiotic, are incorporated into the molecular lattice of the product as impurities. Today, many expensive methods and chemical devices are used for the purification of Amoxicillin by determining 6-APA and 4-HPG, which are defined as impurities. In this study, it was aimed to develop a fast, simple, and specific UV-spectrophotometric method for the determination of 4-HPG and 6-APA. Another aim of this article is to cause as little harm as possible to the environment and human health by using as few chemicals as possible throughout the study. In this study, all attempts to determine 6-APA and 4-HPG, which are impurities in the production of amoxicillin, were carried out with the help of a UV/VIS spectrophotometer. Also, Four different concentrations of NaOH were used as a solvent for each impurity. UV spectra of 4-HPG and 6-APA concentrations between 210 and 400 nm were measured. In the literature, the UV spectrum of 4-HPG has been revealed for the first time in this study and examined in detail. The UV spectrum of 4-HPG was characterized in 3 regions. Again, the response of 6-APA to different NaOH concentrations was demonstrated for the first time in this study. It was determined that the peaks of 6-APA dissolved in NaOH shifted from 222 nm to 227 nm depending on the concentration amount. In addition, it is an ideal green procedure that makes a difference in the literature, as the study is carried out for the control and determination of impurities without the use of any organic solvents or chemicals harmful to the environment.
Effect of thermal deformation and Nb element action on the organization and performance of steel
Authors: Chen Longhai , Li Changrong , Wei Jiajia
Published: May 2022

The influences of Nb element and hot deformation on the strength of steels were systematically investigated. The microstructures and mechanical properties of the steels are determined through optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tensile tests. The nanometer sized carbide particles precipitated in the grain boundary are attributed mainly to severe deformation at high temperature. Of the two steels with different content of Nb element and deformation, the strength of 2#steel is more lager due to more content of Nb can form more precipitates to limit grains growth. Furthermore, the results also shown that adding Nb can refine the microstructure of the steel and effectively improve the mechanical properties, but only thermal deformation has no obvious effect on the improvement of the properties of the steel.
Effects of hybrid polyethylene terephthalate fibre and fly ash on mechanical properties of concrete
Authors: Nkomo N Z , Masu L M , Nziu P K
Published: May 2022

Cracked concrete is a problem due to several factors such as poor maintenance, insufficient reinforcement or steel corrosion leading to crack propagation. There is a need to increase the load-bearing capacity of concrete and increase its life span. The use of waste polyethylene terephthalate fibres and fly ash in a hybrid concrete composite dramatically alleviates the problem of crack propagation and failure sustainably. This study aimed to optimize a waste polyethylene terephthalate fibre/fly ash hybrid cement composite. The concrete test specimens were fabricated using polyethylene terephthalate fibres and fly ash following a full factorial experimental design. The developed specimens were then tested to ascertain their workability and material strength properties. The combined effect of fibre addition and fly ash showed a general decreasing slump value for all quantities of fly ash content. The combined optimum compressive strength for fibre and fly ash was at 0.5% and 15%, respectively, with a strength of 15.54 N mm−2. The optimum split tensile strength of 2.79 N mm−2 was realised at 0.5% fibre and 20% fly ash mass fractions. The optimum flexural strength for fibre and fly ash mass fractions was obtained at 0.5% and 30%, respectively. The trend observed by the rebound number followed that of the compressive strength. However, the non-destructive rebound hammer method gave significantly lower strength values than the destructive test method.
An ecosystem-based natural capital evaluation framework that combines environmental and socio-economic implications of offshore renewable energy developments
Authors: Trifonova Neda , Scott Beth , Griffin Robert , Pennock Shona , Jeffrey Henry
Published: May 2022

There is about to be an abrupt step-change in the use of coastal seas around the globe, specifically by the addition of large-scale offshore renewable energy (ORE) developments to combat climate change. Developing this sustainable energy supply will require trade-offs between both direct and indirect environmental effects, as well as spatial conflicts with marine uses like shipping, fishing, and recreation. However, the nexus between drivers, such as changes in the bio-physical environment from the introduction of structures and extraction of energy, and the consequent impacts on ecosystem services delivery and natural capital assets is poorly understood and rarely considered through a whole ecosystem perspective. Future marine planning needs to assess these changes as part of national policy level assessments but also to inform practitioners about the benefits and trade-offs between different uses of natural resources when making decisions to balance environmental and energy sustainability and socio-economic impacts. To address this shortfall, we propose an ecosystem-based natural capital evaluation framework that builds on a dynamic Bayesian modelling approach which accounts for the multiplicity of interactions between physical (e.g. bottom temperature), biological (e.g. net primary production) indicators and anthropogenic marine use (i.e. fishing) and their changes across space and over time. The proposed assessment framework measures ecosystem change, changes in ecosystem goods and services and changes in socio-economic value in response to ORE deployment scenarios as well as climate change, to provide objective information for decision processes seeking to integrate new uses into our marine ecosystems. Such a framework has the potential of exploring the likely outcomes in the same metrics (both ecological and socio-economic) from alternative management and climate scenarios, such that objective judgements and decisions can be made, as to how to balance the benefits and trade-offs between a range of marine uses to deliver long-term environmental sustainability, economic benefits, and social welfare.
Parametric analysis on drilling of aluminium alloy hybrid composites reinforced with SIC/WC
Authors: Babu S Senthil , Dhanasekaran C , Anbuchezhiyan G , Palani Kumaran
Published: May 2022

Aluminium alloy (Al7075) based hybrid metal matrix composites reinforced with Silicon carbide (SiC) and Tungsten carbide (WC), at 5 wt% each are considered for this investigation, which are developed by stir casting methodology. Material characteristic analysis both at micro and macro (Tensile strength and micro hardness) level were performed. This investigation is further progressed with drilling of the composites using titanium aluminium nitride coated carbide drill (5mm diameter) for varied point angle, feed rate and drill speed. The responses such as thrust force, surface roughness and roundness error were investigated by adopting Response Surface Methodology (RSM). Multiple linear regression (MLR) is developed along with Artificial Neural Networks (ANN) model for predicting the outputs. Scanning Electron Microscope (SEM) image reveals the uniform distribution of ceramic particles in matrix which ascertains enhanced mechanical properties. The parameters such as feed rate and point angle are found to have significant influence during drilling process. The roundness error is found higher with higher point angle which is due to the wider cutting edges in the drill bit. For unconstrained multi-objective optimization, the optimal condition obtained are 128°- point angle, 0.05 mm rev−1 feed rate and 1000 rpm drill speed. For constrained optimization (roundness error ≤0.05 mm), optimal conditions are 118° point angle, 0.05 mm rev−1 feed rate and 1000 rpm drill speed.
Nonexistence and parameter range estimates for convolution differential equations
Authors: Goodrich Christopher
Published: May 2022

We consider nonlocal differential equations with convolution coefficients of the form
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\begin{equation} -M\Big (\big (a*u^q\big )(1)\Big )u(t)=\lambda f\big (t,u(t)\big ),t\in (0,1),\notag \end{equation}

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\begin{equation} -M\Big (\Vert u\Vert _{L^q(0,1)}^{q}\Big )u(t)=\lambda f\big (t,u(t)\big ),t\in (0,1)\notag \end{equation}

is obtained. The range of

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Going to Ganymede
Authors: Bunce Emma
Published: May 2022

In the 2021 RAS Presidential Address, Emma Bunce explores how the JUICE mission will investigate Jupiter's magnetic moon Ganymede and its potential subsurface ocean.
The role of pre-participation cardiac evaluation in the management of an athlete with premature ventricular contraction-induced cardiomyopathy: a case report
Authors: Norouzi Javad , Papadakis Michael , Akbarnejad Ali , Anvari Mehdi
Published: May 2022

Background

Premature ventricular contractions (PVCs) are commonly observed during pre-participation cardiac screening in elite athletes. There is an ongoing debate about the clinical significance of PVCs in athletes and whether burden, morphology, or both should be used to differentiate benign PVCs from PVCs suggestive of cardiac disease.

Case summary

A 28-year-old male athlete was evaluated as part of the pre-participation screening programme. He was asymptomatic, without specific cardiac signs and symptoms. A 12-lead electrocardiogram showed bigeminy PVCs with infundibular morphology and left ventricular outflow tract origin. Left ventricular dilatation and systolic dysfunction without valvular lesions was detected on echocardiography. Cardiac magnetic resonance imaging showed biventricular dilatation and dysfunction without evidence of myocardial fibrosis or fatty infiltration. A 48 h Holter monitoring showed 75191 PVCs (35% of total beats). Radiofrequency ablation was performed, and post-ablation assessments showed no PVCs with normalized ventricular function and dimension.

Discussion

This case demonstrated that a high PVC burden of common morphology does not also represent a benign finding and requires a comprehensive evaluation to rule out any pathological condition. Furthermore, the present case highlights the critical role of pre-participation cardiac evaluation in identifying cardiac disease in asymptomatic athletes.
Early recognition and treatment of pre-VITT syndrome after adenoviral vector-based SARS-CoV-2 vaccination may prevent from thrombotic complications: review of published cases and clinical pathway
Authors: Salih Farid , Kohler Siegfried , Schönborn Linda , Thiele Thomas , Greinacher Andreas , Endres Matthias
Published: May 2022

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but highly morbid complication after adenoviral vector-based SARS-CoV-2 vaccination. The pre-VITT syndrome is defined as vaccine-induced immune thrombocytopenia without thrombosis typically presenting with new-onset headache. This review aims to identify at-risk patients before complications such as cerebral venous sinus thrombosis occur. We review previously published reports of 19 patients (median age 35 years, range 23–74; 16 females) who met the diagnostic criteria for a pre-VITT syndrome. Seven patients progressed to VITT, 12 patients did not. Patients who experienced VITT received delayed treatment. The median interval between the onset of headache and VITT-treatment (i.e. anticoagulation, immune globulins, or corticosteroids) was 5 days (range 1–8 days) compared with 2 days (0–5 days) in those without subsequent VITT (P = 0.033). The interval from onset of headache to anticoagulation was longer in patients with VITT (median 7 vs. 2 days; range 3–9 vs. 0–7 days; P = 0.01). Anticoagulation was safe in all patients with a pre-VITT syndrome as no haemorrhagic complications occurred after anticoagulation was started despite low platelets. The transient decline of platelet count after admission was significantly more pronounced in patients who progressed to VITT (median 67 vs. 0 × 103/µL; range 0–77 × 103/µL vs. 0–10 × 103/µL; P = 0.005). d-dimers did not differ between groups. Pre-VITT syndrome is a ‘red flag’ and allows to identify and preemptively treat patients at-risk of further progression to VITT. However, it must be distinguished from post-vaccination immune thrombocytopenia.
Constraint Shock in Diameter Distribution Models: The Cost of Ignoring Negative Bounds
Authors: Goodwin Adrian N
Published: May 2022

Diameter distributions are invariably fitted with constrained zero or positive lower bounds to prevent negative diameters. Goodwin (2021) found that the bound for the 3-parameter Weibull could be negative for negatively skewed data, and that constraining it to zero reduced model accuracy. The loss of model accuracy due to a bound constraint is referred to here as constraint shock. This article shows that the 4-parameter Kumaraswamy and Johnson’s SB distributions can also have negative lower bounds and exhibit constraint shock. A 3-step parameter recovery method was used to fit these distributions to plots in unthinned mixed species eucalypt plantations and results were compared with the less flexible Weibull. Based on Kolmogorov-Smirnov statistics, mean and maximum constraint shock for the 4-parameter distributions were 19% and 62%, respectively, compared with 19% and 51% for the Weibull, which indicated that constraint shock was not affected by model flexibility. Constraint shock was largely avoided by truncating and normalizing distributions with negative bounds. This work introduces a paradigm shift in diameter distribution modelling and adds clarity to a field that has not previously recognized the existence of constraint shock.

Study Implications: Constraint shock is the loss of accuracy incurred by constraining the negative lower bound of a distribution to a nonnegative value. For a plantation eucalypt dataset in which 83% of plot diameters were negatively skewed, maximum constraint shock was 62% for the Kumaraswamy and Johnson’s SB distributions, and 51% for the less flexible 3-parameter Weibull, based on Kolmogorov-Smirnov statistics. Using distribution expectations of kurtosis, skewness, maximum diameter, and minimum diameter—all independent of bound parameters—a tractable 3-step parameter recovery method is described for unconstrained, constrained, and truncated 3- and 4-parameter distributions. This work introduces a paradigm shift in the treatment of distribution bounds that will result in substantial model improvements for negatively skewed data.
Bat Dentitions: A Model System for Studies at the Interface of Development, Biomechanics, and Evolution
Authors: Santana Sharlene E , Grossnickle David M , Sadier Alexa , Patterson Edward , Sears Karen E
Published: May 2022

The evolution of complex dentitions in mammals was a major innovation that facilitated the expansion into new dietary niches, which imposed selection for tight form–function relationships. Teeth allow mammals to ingest and process food items by applying forces produced by a third-class lever system composed by the jaw adductors, the cranium, and the mandible. Physical laws determine changes in jaw adductor (biting) forces at different bite point locations along the mandible (outlever), thus, individual teeth are expected to experience different mechanical regimes during feeding. If the mammal dentition exhibits functional adaptations to mandible feeding biomechanics, then teeth are expected to have evolved to develop mechanically advantageous sizes, shapes, and positions. Here, we present bats as a model system to test this hypothesis and, more generally, for integrative studies of mammal dental diversity. We combine a field-collected dataset of bite forces along the tooth row with data on dental and mandible morphology across 30 bat species. We (1) describe, for the first time, bite force trends along the tooth row of bats; (2) use phylogenetic comparative methods to investigate relationships among bite force patterns, tooth, and mandible morphology; and (3) hypothesize how these biting mechanics patterns may relate to the developmental processes controlling tooth formation. We find that bite force variation along the tooth row is consistent with predictions from lever mechanics models, with most species having the greatest bite force at the first lower molar. The cross-sectional shape of the mandible body is strongly associated with the position of maximum bite force along the tooth row, likely reflecting mandibular adaptations to varying stress patterns among species. Further, dental dietary adaptations seem to be related to bite force variation along molariform teeth, with insectivorous species exhibiting greater bite force more anteriorly, narrower teeth and mandibles, and frugivores/omnivores showing greater bite force more posteriorly, wider teeth and mandibles. As these craniodental traits are linked through development, dietary specialization appears to have shaped intrinsic mechanisms controlling traits relevant to feeding performance.
Validation of the Soleris® NF-TVC Method for Detection of Aerobic, Mesophilic Microorganisms in Dried Cannabis Flower: AOAC Performance Tested MethodSM 071203
Authors: Le Quynh-Nhi , Mozola Mark , Tudor Alexandra , Horine Leo , Roman Brooke , Montei Carolyn , Zhang Lei , Biswas Preetha , Donofrio Robert
Published: May 2022

Background

Soleris® Non-Fermenting Total Viable Count (NF-TVC) is a growth-based, automated method for semiquantitative detection of aerobic, mesophilic microorganisms in foods and other consumer products such as nutraceuticals and cosmetics. The method was granted AOAC Performance Tested MethodSM status for select foods after successful completion of a validation study.

Objective

The objective of the current study was to validate the Soleris NF-TVC method for use with dried cannabis flower [>0.3% delta 9-tetrahydrocannabinol (THC)].

Methods

The validation consisted of a comparative matrix study in which naturally contaminated dried cannabis flower was tested with the Soleris NF-TVC method and with the AOAC Official Methods of AnalysisSM  966.23 dilution plating method. Multiple lots of dried cannabis flower were obtained, pre-screened for total aerobic, mesophilic viable count levels, and blended to produce test materials at four different levels of contamination ranging from 1.0 × 103 to 2.2 × 105 CFU/g. Each material was tested at three different Soleris detection threshold levels determined by the dilution used to inoculate the Soleris vials. Probability of detection analysis was performed to determine if differences in the number of positive results obtained with the two methods were significant.

Results

For all four dried cannabis flower materials, at all three Soleris test thresholds, there were no significant differences in performance comparing the Soleris and reference dilution plating methods as determined by probability of detection analysis at P < 0.05.

Conclusions

It is concluded that the Soleris NF-TVC method is an accurate and effective method for detection of aerobic, mesophilic microorganisms in dried cannabis flower.

Highlights

The Soleris NF-TVC method provides cannabis industry quality control personnel with an effective method for analysis of dried cannabis flower and produces results in 24–48 h.
Versatility of a Salmonella Loop-Mediated Isothermal Amplification Assay Using Multiple Platforms and Master Mixes in Animal Food Matrices
Authors: Domesle Kelly J , Young Shenia R , McDonald Ryan C , Ge Beilei
Published: May 2022

Background

Improvement in Salmonella detection methods greatly enhances the efficiency of various food testing programs. A Salmonella loop-mediated isothermal amplification (LAMP) assay has been validated in animal food through multi-laboratory validation.

Objective

The study aimed to demonstrate the versatility of this molecular assay while expanding it to multiple platforms and various reagent choices for use in animal food testing.

Methods

Following the U.S. Food and Drug Administration (FDA)’s Guidelines for the Validation of Analytical Methods for the Detection of Microbial Pathogens in Foods and Feeds, we examined the inclusivity, exclusivity, and LOD of the assay using two platforms (7500 Fast and Genie II) and three LAMP master mixes (GspSSD, GspSSD2.0, and WarmStart) in seven animal food matrixes (dry cat food, dry dog food, cattle feed, dairy feed, horse feed, poultry feed, and swine feed). The FDA’s Bacteriological Analytical Manual (BAM) Salmonella culture method was the reference method.

Results

Inclusivity and exclusivity data were consistent among all six platform and master mix combinations with a few exceptions. Comparable LODs were observed down to the single-cell level (WarmStart was 10-fold less sensitive). Performance was similar to the BAM method for detecting fractional positive results in seven animal food matrixes. Nonetheless, LAMP time to positive results and annealing/melting temperature differed among master mixes and platforms.

Conclusion

The Salmonella LAMP assay was successfully validated in two platforms and three master mixes, making it a flexible tool for use by the FDA’s field laboratories in regulatory testing of animal food and for adoption by other food testing programs.

Highlights

We demonstrated the LAMP assay’s versatility on two platforms and three master mixes for the rapid and reliable screening of Salmonella in seven animal food matrixes. GspSSD2.0 was the fastest master mix (time to positive results as early as 3.5 min) while Genie II had several attractive features from a user perspective.
Carbon–water coupling and its relationship with environmental and biological factors in a planted Caragana liouana shrub community in desert steppe, northwest China
Authors: Du Ling-Tong , Ma Long-Long , Pan Hai-Zhu , Qiao Cheng-Long , Meng Chen , Wu Hong-Yue , Tian Jing , Yuan Hong-Yi
Published: May 2022

The carbon and water cycle, an important biophysical process of terrestrial ecosystems, is changed by anthropogenic revegetation in arid and semiarid areas. However, there is still a lack of understanding of the mechanisms of carbon and water coupling in intrinsic ecosystems in the context of human activities. Based on the CO2 and H2O flux measurements of the desert steppe with the planted shrub Caragana liouana, this study explored the carbon and water flux coupling of the ecosystem by analyzing the variations in gross primary productivity (GPP), evapotranspiration (ET) and water use efficiency (WUE) and discussing the driving mechanisms of biological factors. The seasonal variation in climate factors induced a periodic variation pattern of biophysical traits and carbon and water fluxes. The GPP and ET fluctuated in seasons, but the WUE was relatively stable in the growing season. The GPP, ET and WUE were significantly driven by global radiation (Rg), temperature (Ta and Ts), water vapor pressure deficit, leaf area index and plant water stress index (PWSI). However, Rg, temperature and PWSI were the most important factors regulating WUE. Rg and temperature directly affected WUE with a positive effect but indirectly inhibited WUE by rising PWSI. Plant water stress inhibited photosynthesis and transpiration of the planted shrub community in the desert steppe. When the plant water stress exceeded a threshold (PWSI >0.54), the WUE would decrease since the GPP responded more quickly to the plant water stress than ET. Our findings suggest that policies related to large-scale carbon sequestration initiatives under afforestation must first fully consider the status of water consumption and WUE.
Thinking Skills
Authors: Craske Michelle G. , Barlow David H.
Published: May 2022

This chapter explores thinking skills. The main goals of the first section are (1) to help clients recognize that the way they think is critical to their level of fear or anxiety at any given moment and (2) that recognizing negative thinking at a specific and detailed level is necessary before developing different, less negative ways of thinking. In the next section, the main goal is to begin teaching a set of skills for evaluating negative thoughts by looking at the evidence and generating alternative, more evidence-based thoughts. The therapist should then coach the client to identify times when things are blown out of proportion and offer ways of putting things back into perspective. In the last section, the therapist should guide clients as they revisit their worst panic attack, and help them evaluate the sequence of events, with special emphasis on mistaken negative thoughts that lead to increased arousal or behaviors of escape that, in turn, increase anxiety.
Facing Physical Symptoms
Authors: Craske Michelle G. , Barlow David H.
Published: May 2022

This chapter studies the process of conducting symptom exercises with the client. Facing fear of physical symptoms means to deliberately expose oneself to the feared sensations that trigger panic attacks. Typically, these types of sensations are avoided. Subtle avoidance includes distracting oneself from thoughts about physical sensations, while obvious avoidance includes not engaging in activities, such as arguments or sexual relations, that elicit strong sensations. Avoidance precludes relearning and instead maintains the vigilance for and acute sensitivity to such sensations. Hence, an essential component of treatment is to confront repeatedly the feared sensations, so clients learn that they can tolerate the sensations and associated anxiety and that the sensations are not harmful. After a number of such practices, anxiety over the symptoms eventually declines. This process begins by inducing sensations using a set of standardized and simulated exercises, such as spinning and hyperventilating.
The Nature of Panic Disorder and Agoraphobia
Authors: Barlow David H. , Craske Michelle G.
Published: May 2022

This chapter provides an overview of the nature of panic disorder and agoraphobia. The key features of panic disorder are (1) one or more episodes of abrupt, intense fear or discomfort (i.e., a panic attack) and (2) persistent anxiety or worry about the recurrence of panic attacks, their consequences, or life changes as a result of the attacks. Another feature of panic disorder is avoiding, hesitating about, or feeling very nervous in situations where panic attacks or other physical symptoms are expected to occur. Typically, these situations are ones where one may not be able to escape or find help. Avoiding situations from which escape might be difficult or where help may be unavailable in the event of a panic attack or other physical symptoms is called agoraphobia. The chapter then outlines the typical agoraphobia situations. The kind of treatment that is described in this program is called cognitive behavioral therapy (CBT), and it is designed to educate and to teach constructive ways of coping.
Negative Cycles of Panic and Agoraphobia
Authors: Barlow David H. , Craske Michelle G.
Published: May 2022

This chapter focuses on the importance of understanding the negative cycles that contribute to panic attacks and agoraphobia. There are three major parts to the emotions of anxiety and panic: physical symptoms, thoughts, and behaviors. Physical symptoms, thoughts, and behaviors contribute to each other in what is called a negative cycle. Negative thoughts lead to fear, and fear leads to more physical symptoms and escape behaviors that snowball into more negative thoughts, and so on. The end result is intense fear or panic—a panic cycle. By understanding these cycles, one will develop a good awareness of what causes panic attacks. This program teaches ways of interrupting the panic and agoraphobia cycles, including the development of breathing skills and thinking skills.
Mastery of Your Anxiety and Panic
Authors: Craske Michelle G. , Barlow David H. , Woodard Lauren S.
Published: May 2022

This edition of the Mastery of Your Anxiety and Panic: Workbook for Brief Six-Session Version for Primary Care and Related Settings outlines a time-limited treatment for those dealing with panic disorder and agoraphobia. If a patient primarily seeks treatment from a family doctor, this guide will be useful. The program described is based on the principles of cognitive behavioral therapy (CBT). It can be delivered by a general practitioner or other health or mental health care provider in primary care or related settings in up to six sessions. A modified version of the more intensive 12-session program that currently exists, this treatment represents an introduction of the skills and techniques for overcoming panic disorder that patients can easily learn and continue on their own.
Learning to Face Your Fear
Authors: Craske Michelle G. , Barlow David H. , Woodard Lauren S.
Published: May 2022

This chapter evaluates the process of learning to face one’s fear. The final step of breathing skills training is to use it at times when one feels anxious or panicky, or when one notices panic symptoms. The goal is not to immediately eliminate fear and anxiety; rather, the goal of breathing skills is to regulate breathing so that one can continue whatever activity one is involved in (rather than to escape or avoid) and face one’s fears and anxieties. It is important to face the physical symptoms directly so that one can learn that the symptoms are not harmful; one can handle the symptoms and the anxiety; and eventually, the anxiety about the physical symptoms will decrease. The goal of this part of treatment is to help one directly face the physical symptoms that make one anxious, replace one’s mistaken beliefs with more realistic thinking, and interrupt the conditioning. The chapter then outlines the rules for the repeated practice with physical symptoms.
Novel Use of Seraph-100™ Blood Purification Therapy in Heat Stroke
Authors: Miller Mary K , Spiller Robert E , Mount Cristin A , Colombo Christopher , Khayat Maurice I
Published: May 2022

The Seraph-100™ is a purification filter that blunts cytokine storm, providing a more favorable environment to establish immune homeostasis. We present a novel case of compassionate use of Seraph filter in a young, healthy active duty service member with heat injury-induced massive inflammatory response. The patient is a previously healthy 26-year-old male with altered mental status, tachycardia, fever to 40.3 °C, and hypotension after losing consciousness during a 4-mile run. He had a history of one heat injury in college and took no medications or supplements. Initial workup demonstrated hemoconcentration, leukocytosis, and hyperkalemia. He was intubated, received isotonic crystalloid fluid, and was admitted to the intensive care unit. The patient developed vasopressor-resistant shock and multiorgan failure with rhabdomyolysis requiring continuous renal replacement therapy. The addition of the Seraph resulted in improved hemodynamic stability, decreased inflammatory markers, and improved organ function. Approximately 1 week after the final Seraph treatment, the patient had an abrupt massive lower gastrointestinal bleed and was transitioned to comfort care by family. We present the novel use of Seraph in the setting of multiorgan failure and hyperinflammatory state due to heat injury. The patient’s vasopressor refractory distributive shock was believed to be secondary to heat stroke-induced massive inflammatory response, leading to a trial of Seraph therapy. This case demonstrates that the Seraph filter has the potential to improve hemodynamic instability and reduce cytokine storm in nonsepsis patients.
Pulmonary Barotrauma in a BUD/S Candidate Following Shallow Dives Using the MK 25 Rebreather
Authors: Andrew Brian , Boswell Gilbert , Sebreros Benjamin , Cusmano Paul
Published: May 2022

Pulmonary barotrauma of ascent is a well-recognized risk of compressed air diving in the civilian and military diving communities. Chest imaging is a beneficial adjunct to clinical evaluation in screening select individuals for fitness to dive, evaluating dive-related injuries, and safely returning individuals to diving duty. We present a case of a 26-year-old male U.S. Navy Ensign and Basic Underwater Demolition/SEAL (BUD/S) candidate who experienced pulmonary barotrauma following two shallow dives to a maximum depth of 18 feet of seawater using the MK-25 100% oxygen rebreather. A chest radiograph showed a left upper lobe peripheral wedge-shaped opacity abutting the pleural surface. A subsequent computerized tomography (CT) scan of the chest showed multifocal areas of peripheral pulmonary hemorrhage associated with small pneumatoceles. Two months after the diving injury, chest CT showed resolution of the pulmonary hemorrhage and pneumatoceles. Diving-related pulmonary barotrauma occurs most often secondary to breath-holding on ascent by inexperienced divers and is one of the most common diving injuries seen in BUD/S candidates. The risk of pulmonary barotrauma may be decreased through adequate training and thorough medical screening to include assessing for symptoms of infection before every dive. In cases of acute pulmonary barotrauma, chest radiographs may be used to screen for thoracic injury. Chest CT with inspiratory and expiratory sequences should be used to screen dive candidates on a case-by-case basis and to evaluate lung injury and predisposing pulmonary conditions following pulmonary barotrauma.
Testing for Cryptococcosis at a Major Commercial Laboratory—United States, 2019–2021
Authors: Benedict Kaitlin , Gold Jeremy A W , Dietz Stephanie , Anjum Seher , Williamson Peter R , Jackson Brendan R
Published: May 2022

Background

Cryptococcosis is a serious opportunistic fungal disease, and the proportion of cases among patients with immunosuppressive conditions other than HIV or organ transplant has increased. Understanding laboratory testing patterns for cryptococcosis is useful for estimating its true burden and developing testing guidance.

Methods

We identified cryptococcosis tests (cryptococcal antigen [CrAg], cryptococcal antibody, and fungal cultures) performed at a major national commercial laboratory ordered during March 1, 2019–October 1, 2021, and analyzed test results, patient and provider features, reasons for testing, geography, and temporal trends.

Results

Among 29 180 serum CrAg tests, 4422 (15.2%) were positive, and among 10 724 cerebrospinal fluid (CSF) CrAg tests, 492 (4.6%) were positive. Frequent reasons for serum CrAg testing in nonhospital settings (10 882 tests) were HIV (44.6%) and cryptococcosis (17.0%); other underlying conditions were uncommonly listed (<10% total). Serum CrAg positivity declined from 25.6% in October 2019 to 11.3% in September 2021. The South had the highest positivity for serum CrAg tests (16.6%), CSF CrAg tests (4.7%), and fungal cultures (0.15%). Among 5009 cryptococcal antibody tests, 5 (0.1%) were positive.

Conclusions

Few outpatient serum CrAg tests were performed for patients with immunocompromising conditions other than HIV, suggesting potential missed opportunities for early detection. Given the high positive predictive value of CrAg testing, research is needed to improve early diagnosis, particularly in patients without HIV. Conversely, the low yield of antibody testing suggests that it may be of low value. The decline in CrAg positivity during the COVID-19 pandemic warrants further investigation.
Real-world evidence on methotrexate-free subcutaneous tocilizumab therapy in patients with rheumatoid arthritis: 24-week data from the SIMPACT study
Authors: Nagy György , Géher Pál , Tamási László , Drescher Edit , Keszthelyi Péter , Pulai Judit , Czirják László , Szekanecz Zoltán , Kiss Gergely , Kovács László
Published: May 2022

Objectives

The aim of the SIMPACT study was to evaluate the efficacy and safety of MTX-free s.c. tocilizumab (TCZ) therapy in RA patients.

Methods

SIMPACT was an open-label, non-controlled, non-randomized, non-interventional study, in which RA patients for whom the treating physicians ordered s.c. TCZ were observed during a 24-week treatment period in Hungarian centres. Although the use of MTX was avoided during the study period, other conventional synthetic DMARDs, oral CSs and NSAIDs were allowed. Study endpoints included the change in DAS28 and clinical activity index (CDAI) scores, the proportion of patients achieving remission in the whole population and in subgroups defined based on prior RA treatment history, and age, weight or biological sex post hoc. The extent of supplementary medication use was monitored.

Results

Three hundred and thirty-seven RA patients were enrolled in 18 study centres. TCZ therapy significantly decreased the disease activity measured by both DAS28 (P = 0.0001) and CDAI (P = 0.0001). Clinical response was more pronounced in biologic-naïve patients and was lower in patients >75 years of age. In the whole population, DAS28 ESR or CRP and CDAI remission rates were 70.10%, 78.95% and 33.59%, respectively. In patients <45 years of age, the CDAI remission rate doubled (67.86%). A significant decrease in the frequency of co-administered medication was reported, including oral CSs and DMARDs.

Conclusion

Real-world clinical evidence on s.c. TCZ reported here is in line with the efficacy outcomes of randomized clinical trials. Subgroup analysis revealed that TCZ was more effective in biologic-naïve patients and in those <75 years old.

Trial registration

ClinicalTrials.gov, http://www.clinicaltrials.gov, NCT02402686.