bluuebunny/crossref_metadata_2025 huggingface dataset:
Northern landscapes in transition: Evidence, approach and ways forward using the Krycklan Catchment Study
Authors: Laudon Hjalmar , Hasselquist Eliza Maher , Peichl Matthias , Lindgren Kim , Sponseller Ryan , Lidman Fredrik , Kuglerová Lenka , Hasselquist Niles J. , Bishop Kevin , Nilsson Mats B. , Ågren Anneli M.
Published: April 2021

Improving our ability to detect changes in terrestrial and aquatic systems is a grand challenge in the environmental sciences. In a world experiencing increasingly rapid rates of climate change and ecosystem transformation, our ability to understand and predict how, when, where, and why changes occur is essential for adapting and mitigating human behaviours. In this context, long‐term field research infrastructures have a fundamentally important role to play. For northern boreal landscapes, the Krycklan Catchment Study (KCS) has supported monitoring and research aimed at revealing these changes since it was initiated in 1980. Early studies focused on forest regeneration and microclimatic conditions, nutrient balances and forest hydrology, which included monitoring climate variables, water balance components, and stream water chemistry. The research infrastructure has expanded over the years to encompass a 6790 ha catchment, which currently includes 11 gauged streams, ca. 1000 soil lysimeters, 150 groundwater wells, >500 permanent forest inventory plots, and a 150 m tall tower (a combined ecosystem‐atmosphere station of the ICOS, Integrated Carbon Observation System) for measurements of atmospheric gas concentrations and biosphere‐atmosphere exchanges of carbon, water, and energy. In addition, the KCS has also been the focus of numerous high resolution multi‐spectral LiDAR measurements and large scale experiments. This large collection of equipment and data generation supports a range of disciplinary studies, but more importantly fosters multi‐, trans‐, and interdisciplinary research opportunities. The KCS attracts a broad collection of scientists, including biogeochemists, ecologists, foresters, geologists, hydrologists, limnologists, soil scientists, and social scientists, all of whom bring their knowledge and experience to the site. The combination of long‐term monitoring, shorter‐term research projects, and large‐scale experiments, including manipulations of climate and various forest management practices, has contributed much to our understanding of boreal landscape functioning, while also supporting the development of models and guidelines for research, policy, and management.
The effects of ditch dams on water‐level dynamics in tropical peatlands
Authors: Putra Santosa Sandy , Holden Joseph , Baird Andy J.
Published: April 2021

A significant proportion of tropical peatlands has been drained for agricultural purposes, resulting in severe degradation. Hydrological restoration, which usually involves blocking ditches, is therefore a priority. Nevertheless, the influence of ditch blocking on tropical peatland hydrological functioning is still poorly understood. We studied water‐level dynamics using a combination of automated and manual dipwells, and also meteorological data during dry and wet seasons over 6 months at three locations in Sebangau National Park, Kalimantan, Indonesia. The locations were a forested peatland (Forested), a drained peatland with ditch dams (Blocked), and a drained peatland without ditch dams (Drained). In the dry season, water tables at all sites were deeper than the Indonesian regulatory requirement of 40 cm from the peat surface. In the dry season, the ditches were dry and water did not flow to them. The dry season water‐table drawdown rates — solely due to evapotranspiration — were 9.3 mm day−1 at Forested, 9.6 mm day−1 at Blocked, but 12.7 mm day−1 at Drained. In the wet season, the proportion of time during which water tables in the wells were deeper than the 40 cm limit ranged between 16% and 87% at Forested, 0% at Blocked, and between 0% and 38% at Drained. In the wet season, water flowed from the peatland to ditches at Blocked and Drained. The interquartile range of hydraulic gradients between the lowest ditch outlet and the farthest well from ditches at Blocked was 3.7 × 10−4 to 7.8 × 10−4 m m−1, but 1.9 × 10−3 to 2.6 × 10−3 m m−1 at Drained. Given the results from Forested, a water‐table depth limit policy based on field data may be required, to reflect natural seasonal dynamics in tropical peatlands. Revised spatial designs of dams or bunds are also required, to ensure effective water‐table management as part of tropical peatland restoration.
Bioremediation of coke plant wastewater from steel industry with mixed activated sludge–microalgal consortium in lab‐scale semi‐continuous mode
Authors: Kaur Nagi Gurpreet , Chetry Rosy , Singh Nisha , Sinha Apurva , Shinde Omkar Avinash
Published: April 2021

BACKGROUND

Removal of toxicities from wastewater has always demanded great attention as it has life‐threatening impacts on every living being and the environment. In the present study, bioremediation of ammonia and cyanide from coke plant wastewater (CPWW) by using bacterial consortia with activated sludge (AS) supplemented with microalgal (MA) biomass in semi‐continuous mode was performed. Parameters such as pH, total dissolved solids (TDS), dissolved oxygen (DO) and bacterial cell viability, along with any significant effect on the growth of microalgal cells in wastewater, was investigated by determining its specific growth rate (μ).

RESULTS

With pH values remaining constant for the system, the ammonia removal rate with microalgae additions was approximately 38.3% lower than that with AS. Similarly, the cyanide removal rate after addition of microalgae to the system showed a difference of 43% with AS treatment. TDS levels dropped by 22.18% and the concentration of DO increased by 21.91% in comparison to the values obtained by treatment of CPWW with AS and MA to CPWW with AS alone.

CONCLUSION

Microalgae additions effectively increase the efficiency of AS treatment of CPWW and thus can be taken to field trials for developing a cost‐effective and environmentally friendly strategy of wastewater treatment. © 2021 Society of Chemical Industry
Enhancement of the quick lime‐based solidification/stabilization of oily wastes using modified clay
Authors: Jebeli Mojtaba Tayebi , Heidarzadeh Nima
Published: April 2021

BACKGROUND

This research investigated the solidification/stabilization process (S/S) efficiency of contaminated soil by total petroleum hydrocarbons (TPH) in the waste of a used oil treatment plant using quick lime (QL) as a binder and modified clay (MC) as an additive. Several objectives were considered, including reducing the mobility and leaching of TPH, investigating the effect of MC on the QL hydration process in the presence of organic matter, the possibility of S/S waste reuse, and estimating the S/S cost for the optimum mixture.

RESULTS

The unconfined compressive strength (UCS) increased about 45% by increasing 25% of QL without MC, but these S/S wastes did not satisfy the waste reuse standards. Additionally, adding any ratio of MC to samples containing QL increased UCS significantly. The UCS of all samples at the age of 28 days with different QL and MC proportions obtained more than 350 kPa (the minimum UCS required for S/S waste disposal in the landfill). Moreover, the toxicity characteristic leaching procedure (TCLP) test revealed that TPH leaching of contaminated soil was 3.8 mg L−1 but adding only 15% of QL could reduce TPH leaching to less than 1 mg L−1, which is the maximum allowable TPH leaching.

CONCLUSION

The combination of QL and MC decreased TPH leaching, significantly. The scanning electron microscopy analysis also showed that QL hydration was improved by increasing the amount of MC. Finally, a sample with 35% QL and 15% MC was selected as an optimum sample due to its cost of $80.5/ton. © 2021 Society of Chemical Industry (SCI).
Rainfall asymmetries of the western North Pacific tropical cyclones as inferred from GPM
Authors: Liang Junyi , Chan Kelvin T. F.
Published: April 2021

It has been revealed that the vertical wind shear (VWS) can result in the rainfall asymmetry of tropical cyclone (TC), where the VWS is conventionally defined as the environmental horizontal winds between 200‐ and 850‐hPa levels within a certain area from the TC centre. The rainfall maximum is generally displaced downshear to downshear‐left side in the Northern Hemisphere or downshear to downshear‐right side in the Southern Hemisphere. Here, we revisit the rainfall asymmetries of TCs over the western North Pacific using the state‐of‐art Global Precipitation Measurement data. Observations pose that using the conventional VWS to interpret the TC rainfall asymmetry is inopportune. The conventional VWS can only largely grasp the rainfall asymmetry in the inner core of TC, but not in the outer core. We, therefore, explicitly propose a new VWS, namely the effective VWS, to fill this gap. The effective shear layer responsible for the rainfall asymmetry is a function of TC intensity and core region. In addition, we suggest that the angle difference between the effective shears for the inner‐core and outer‐core rainfall asymmetries can help to comprehend the spirality of the rainfall asymmetries that are, the fashions, or patterns of the rainbands. Meanwhile, the moisture flux convergence and storm motion show little effect on the rainfall asymmetry. This study advances the understanding of TC rainfall asymmetry and provides scientific support for disaster prediction, prevention, and mitigation.
Pickering emulsion‐templated ionotropic gelation of tocotrienol microcapsules: effects of alginate and chitosan concentrations and gelation process parameters
Authors: Tan Phui Yee , Tan Tai Boon , Chang Hon Weng , Mwangi William W , Tey Beng Ti , Chan Eng Seng , Lai Oi Ming , Liu Yuanfa , Wang Yong , Tan Chin Ping
Published: April 2021

BACKGROUND

Throughout the past decade, Pickering emulsion has been increasingly utilized for the encapsulation of bioactive compounds due to its high stability and biocompatibility. In the present work, palm tocotrienols were initially encapsulated in a calcium carbonate Pickering emulsion, which was then subjected to alginate gelation and subsequent chitosan coating. The effects of wall material (alginate and chitosan) concentrations, gelation pH and time, and chitosan coating time on the encapsulation efficiency of palm tocotrienols were explored.

RESULTS

Our findings revealed that uncoated alginate microcapsules ruptured upon drying and exhibited low encapsulation efficiency (13.81 ± 2.76%). However, the addition of chitosan successfully provided a more complex and rigid external wall structure to enhance the stability of the microcapsules. By prolonging the crosslinking time from 5 to 30 min and increasing the chitosan concentration from 0.1% to 0.5%, the oil encapsulation efficiency was increased by 28%. Under the right gelation pH (pH 4), the extension of gelation time from 1 to 12 h resulted in an increase in alginate‐Ca2+ crosslinkings, thus strengthening the microcapsules.

CONCLUSION

With the optimum formulation and process parameters, a high encapsulation efficiency (81.49 ± 1.75%) with an elevated oil loading efficiency (63.58 ± 2.96%) were achieved. The final product is biocompatible and can potentially be used for the delivery of palm tocotrienols. © 2021 Society of Chemical Industry.
Mesenchymal stromal cell therapy for pancreatitis: Progress and challenges
Authors: Ma Zhilong , Zhou Jia , Yang Tingsong , Xie Wangcheng , Song Guodong , Song Zhenshun , Chen Ji
Published: April 2021

Pancreatitis is a common gastrointestinal disease with no effective therapeutic options, particularly for cases of severe acute and chronic pancreatitis (CP). Mesenchymal stromal cells (MSCs) are multipotent cells with diverse biological properties, including directional migration, paracrine, immunosuppressive, and antiinflammatory effects, which are considered an ideal candidate cell type for repairing tissue damage caused by various pathogenies. Several researchers have reported significant therapeutic efficacy of MSCs in animal models of acute and CP. However, the specific underlying mechanisms are yet to be clarified and clinical application of MSCs as pancreatitis therapy has rarely been reported. This review mainly focuses on the potential and challenges in clinical application of MSCs for treatment of acute and CP, along with discussion of the underlying molecular mechanisms.
High‐throughput identification of conditional MHCI ligands and scaled‐up production of conditional MHCI complexes
Authors: Darwish Martine , Wichner Sara , Li Jenny , Chang Jiun Chiun , Tam Christine , Franke Yvonne , Li Hong , Chan Pamela , Blanchette Craig
Published: April 2021

Despite the need to monitor the impact of Cancer Immunotherapy (CI)/Immuno‐Oncology (IO) therapeutics on neoantigen‐specific T‐cell responses, very few clinical programs incorporate this aspect of immune monitoring due to the challenges in high‐throughput (HTP) generation of Major Histocompatibility Complex Class I (MHCI) tetramers across a wide range of HLA alleles. This limitation was recently addressed through the development of MHCI complexes with peptides containing a nonnatural UV cleavable amino acid (conditional MHCI ligands) that enabled HTP peptide exchange upon UV exposure. Despite this advancement, the number of alleles with known conditional MHCI ligands is limited. We developed a novel workflow to enable identification and validation of conditional MHCI ligands across a range of HLA alleles. First, known peptide binders were screened via an enzyme‐linked immunosorbent assay (ELISA) assay. Conditional MHCI ligands were designed using the highest‐performing peptides and evaluated in the same ELISA assay. The top performers were then selected for scale‐up production. Next‐generation analytical techniques (LC/MS, SEC‐MALS, and 2D LC/MS) were used to characterize the complex after refolding with the conditional MHCI ligands. Finally, we used 2D LC/MS to evaluate peptide exchange with these scaled‐up conditional MHCI complexes after UV exposure with validated peptide binders. Successful peptide exchange was observed for all conditional MHCI ligands upon UV exposure, validating our screening approach. This approach has the potential to be broadly applied and enable HTP generation of MHCI monomers and tetramers across a wider range of HLA alleles, which could be critical to enabling the use of MHCI tetramers to monitor neoantigen‐specific T‐cells in the clinic.
MicroRNA‐315‐5p promotes rice black‐streaked dwarf virus infection by targeting a melatonin receptor in the small brown planthopper
Authors: Zhang Jianhua , Dong Yan , Wang Man , Wang Haitao , Yi Dianshan , Zhou Yijun , Xu Qiufang
Published: April 2021

BACKGROUND

MicroRNAs (miRNAs), a class of small non‐coding endogenous RNAs, play key roles in various biological processes. Most plant viruses are transmitted by insect vectors. However, little is known about the function of miRNAs on plant virus‐insect host interaction.

RESULTS

We investigated the role of miR‐315‐5p in regulation of plant viral infection in insects using a rice black‐streaked dwarf virus (RBSDV) and small brown planthopper (SBPH) interaction system. Our results showed that miR‐315‐5p had the highest expression level in 2nd‐instar nymph, and was highly expressed in the salivary gland and midgut in SBPH. miR‐315‐5p was in response to and regulated RBSDV infection in SBPH. Injection of miR‐315‐5p mimic, agomir‐315, significantly increased the RBSDV accumulation, whereas injection of miR‐315‐5p inhibitor, antagomir‐315, reduced virus accumulation in SBPH. Furthermore, a melatonin receptor was identified as a target gene of miR‐315‐5p by the dual luciferase reporter assay. Knockdown of the melatonin receptor significantly increased the expression of RBSDV coat protein gene S10 and replication related genes, S5‐1, S6, and S9‐1. Furthermore, treatment with melatonin receptor antagonist luzindole and activator agomelatine significantly increased and reduced RBSDV accumulation in SBPH, respectively. Compared to the control, miR‐315‐5p did not affect the efficiency of RBSDV acquisition in SBPH. However, the efficiency of RBSDV transmission was significantly reduced after injecting antagomir‐315.

CONCLUSION

Taken together, our data reveal that miR‐315‐5p is beneficial for RBSDV infection in its insect vector by directly targeting a melatonin receptor. These findings provide a new insight to the function of miRNAs in virus‐insect vector interaction. © 2021 Society of Chemical Industry.
Sublethal fluazaindolizine doses inhibit development of the cyst nematode Heterodera schachtii during sedentary parasitism
Authors: Matera Christiane , Grundler Florian MW , Schleker A Sylvia S
Published: April 2021

BACKGROUND

Fluazaindolizine is a new compound for the control of plant‐parasitic nematodes (PPNs) with an unknown and novel mode‐of‐action. This compound is very effective against important PPNs. However, investigations elucidating the impact of sublethal fluazaindolizine doses on early nematode virulence and plant–nematode interaction parameters are lacking.

RESULTS

The effect of direct exposure of Heterodera schachtii juveniles to 50 ppm fluazaindolizine was negligible. Infection assays revealed a 57% reduction in adult females at 1.25 ppm and a 46% reduction in offspring at 40 ppm when juveniles were soaked in the compound for 48 h and subsequently inoculated onto Arabidopsis thaliana. Pre‐incubation of A. thaliana roots with fluazaindolizine was not effective against H. schachtii. Conversely, supplementing the plant growth medium with fluazaindolizine led to a significant reduction of adults (−35%), females (−75%) and female size at 1.25 ppm and nearly completely inhibited nematode parasitism at 5 ppm. The impact of fluazaindolizine on A. thaliana was dependent on plant age, compound concentration and duration of contact. Very low sublethal fluazaindolizine concentrations, 5 or 10 ppm, did not interfere with nematode mobility, host finding, penetration, and induction of the feeding site, but specifically inhibited sedentary nematode development inside the root in a concentration‐dependent manner.

CONCLUSION

Fluazaindolizine does not have direct toxicity against PPN infective juveniles, but has a clear effect on nematodes during sedentary development. The formation of females and the development of offspring are strongly reduced. It will be interesting to identify the underlying mechanism in the future. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Evaluating errors due to unresolved scales in convection‐permitting numerical weather prediction
Authors: Waller Joanne A. , Dance Sarah L. , Lean Humphrey W.
Published: April 2021

In numerical weather prediction (NWP), observations and models are quantitatively compared for the purposes of data assimilation and forecast verification. The spatial and temporal scales represented by the observation and model may differ and this results in a scale mismatch error which may be biased and correlated. The aim of this paper is to investigate the structure of representation error in convection‐permitting NWP models for four meteorological variables: temperature, specific humidity, zonal and meridional wind. We use high‐resolution data from the experimental Met Office London Model (approximately 300 m grid‐length) to simulate perfect observations and lower‐resolution model data. The scale mismatch error and its bias, variance and correlation are calculated from the perfect observation and low‐resolution model equivalents. Our new results show that the scale mismatch bias is significant in the boundary layer for temperature and specific humidity, whereas the variance is significant in the boundary layer for all analysed variables. Contrary to previous studies using low‐resolution (km‐scale) data, horizontal correlations are shown to be insignificant. However, all variables exhibit considerable vertical representation error correlation throughout the boundary layer. Our results suggest that significant biases and vertical correlations exist that should be accounted for to give maximum observation impact in data assimilation and for fairness in model verification and validation.
The Cayley Graph of Neumann Subgroups
Authors: Matraś Andrzej , Siemaszko Artur
Published: April 2021

All Cayley representations of the distant graph $$\Gamma _{\mathbb Z}$$

Γ
Z

over integers are characterized as Neumann subgroups of the extended modular group. Possible structures of Neumann subgroups are revealed and it is shown that every such structure can be realized.
Surgical management of displaced femoral neck fractures in patients with dementia: a comparison in mortality between hemiarthroplasty and pins/screws
Authors: Ioannidis Ioannis , Mohammad Ismail Ahmad , Forssten Maximilian Peter , Ahl Rebecka , Cao Yang , Borg Tomas , Mohseni Shahin
Published: April 2021

Introduction

Dementia is common in patients with hip fractures and is strongly associated with increased postoperative mortality. The choice of surgical intervention for displaced femoral neck fractures (dFNF) in patients with dementia has been a matter of debate. This study aims to investigate how short- and long-term mortality differs between those who have been operated with hemiarthroplasty or pins/screws.

Methods

All patients with dementia and dFNF, i.e., Garden III and IV, who underwent primary emergency hip fracture surgery, with either hemiarthroplasty or pins/screws, in Sweden between Jan 1, 2008 and Dec 31, 2017 were eligible for inclusion in the current study. Patients were divided into two groups based on the surgical intervention: hemiarthroplasty and pins/screws. The primary outcome of interest was 30-day postoperative mortality, and the secondary outcome was 1-year postoperative mortality. Poisson and Cox regression analyses were performed both before and after propensity score matching.

Results

A total of 9394 cases met the inclusion criteria; 84% received hemiarthroplasty and 16% received pins/screws. In the unmatched analysis, the adjusted incidence rate ratio (IRR) for 30-day postoperative mortality was not affected by the chosen surgical method (adj. IRR 0.96, CI 95% 0.83–1.12, p = 0.629). After propensity score matching, similar results were observed with no difference in 30-day postoperative mortality (adj. IRR 0.89, CI 95% 0.74–1.09, p = 0.286). There was a statistically significant decrease in the risk of 1-year postoperative mortality in the hemiarthroplasty group compared to the pins/screws group, both before and after propensity score matching.

Conclusion

This study could not demonstrate any difference in 30-day mortality in patients with dementia and dFNFs when comparing hemiarthroplasty with pins/screws. Patients that received hemiarthroplasties did, however, have a lower risk of 1-year postoperative mortality.
Acute alcohol consumption increases systemic endotoxin bioactivity for days in healthy volunteers—with reduced intestinal barrier loss in female
Authors: Sturm Ramona , Haag Florian , Janicova Andrea , Xu Baolin , Vollrath Jan Tilmann , Bundkirchen Katrin , Dunay Ildiko Rita , Neunaber Claudia , Marzi Ingo , Relja Borna
Published: April 2021

Objective

Trauma is the most common cause of death among young adults. Alcohol intoxication plays a significant role as a cause of accidents and as a potent immunomodulator of the post-traumatic response to tissue injury. Polytraumatized patients are frequently at risk to developing infectious complications, which may be aggravated by alcohol-induced immunosuppression. Systemic levels of integral proteins of the gastrointestinal tract such as syndecan-1 or intestinal fatty acid binding proteins (FABP-I) reflect the intestinal barrier function. The exact impact of acute alcohol intoxication on the barrier function and endotoxin bioactivity have not been clarified yet.

Methods

22 healthy volunteers received a precisely defined amount of alcohol (whiskey–cola) every 20 min over a period of 4 h to reach the calculated blood alcohol concentration (BAC) of 1‰. Blood samples were taken before alcohol drinking as a control, and after 2, 4, 6, 24 and 48 h after beginning with alcohol consumption. In addition, urine samples were collected. Intestinal permeability was determined by serum and urine values of FABP-I, syndecan-1, and soluble (s)CD14 as a marker for the endotoxin translocation via the intestinal barrier by ELISA. BAC was determined.

Results

Systemic FABP-I was significantly reduced 2 h after the onset of alcohol drinking, and remained decreased after 4 h. However, at 6 h, FABP-I significantly elevated compared to previous measurements as well as to controls (p < 0.05). Systemic sCD14 was significantly elevated after 6, 24 and 48 h after the onset of alcohol consumption (p < 0.05). Systemic FABP-I at 2 h after drinking significantly correlated with the sCD14 concentration after 24 h indicating an enhanced systemic LPS bioactivity. Women showed significantly lower levels of syndecan-1 in serum and urine and urine for all time points until 6 h and lower FABP-I in the serum after 2 h.

Conclusions

Even relative low amounts of alcohol affect the immune system of healthy volunteers, although these changes appear minor in women. A potential damage to the intestinal barrier and presumed enhanced systemic endotoxin bioactivity after acute alcohol consumption is proposed, which represents a continuous immunological challenge for the organism and should be considered for the following days after drinking.
Ultracongruent insert design is a safe alternative to posterior cruciate-substituting total knee arthroplasty: 5-year results of a randomized controlled trial
Authors: Lützner Jörg , Beyer Franziska , Lützner Cornelia , Riedel Roman , Tille Eric
Published: April 2021

Purpose

If substitution of the posterior cruciate ligament in total knee arthroplasty is necessary, there are two options available: posterior stabilized (PS) design with a post-cam mechanism or anterior-lipped ultracongruent (UC) inserts. UC inserts have the advantage that no femoral box is necessary and a standard femoral component can be used. The aim of this study was to compare the range of motion (ROM) and patient-reported outcome (PRO) after UC and PS fixed-bearing TKA. Better ROM in PS TKA and no difference in PRO between both designs was hypothesized.

Methods

A randomized controlled trial with 127 patients receiving a fixed-bearing UC or PS design of the same knee system was performed. Nine patients died and there were four revision surgeries. 107 patients completed the 5-year follow-up. Patient-reported outcome was assessed. Patellofemoral problems were evaluated using selected applicable questions of the Oxford Knee Score (getting up from a table, kneeling, climbing stairs).

Results

Surgical time was 10 min shorter in the UC group (p < 0.001). After 5 years, both groups demonstrated good knee function and health-related quality of life without significant differences between the groups. Both groups demonstrated a high satisfaction score and the majority of patients would undergo this surgery again. Patellofemoral problems were recognized more frequently in the PS group (p = 0.025).

Conclusion

Both designs demonstrated similar good results after 5 years. Stabilization with an anterior-lipped UC insert can be considered a safe alternative to the well-established PS design if cruciate substitution is necessary.

Level of evidence

1.
Many closed K-magnetic geodesics on $${\mathbb {S}}^2$$
Authors: Musina Roberta , Zuddas Fabio
Published: April 2021

In this paper we adopt an alternative, analytical approach to Arnol’d problem [4] about the existence of closed and embedded K-magnetic geodesics in the round 2-sphere $${\mathbb {S}}^2$$

S

2

, where $$K: {\mathbb {S}}^2 \rightarrow {\mathbb {R}}$$

K
:

S

2

→
R

is a smooth scalar function. In particular, we use Lyapunov-Schmidt finite-dimensional reduction coupled with a local variational formulation in order to get some existence and multiplicity results bypassing the use of symplectic geometric tools such as the celebrated Viterbo’s theorem [21] and Bottkoll results [7].
Biomechanics of insect cuticle: an interdisciplinary experimental challenge
Authors: Stamm Karen , Saltin Brian Daniel , Dirks Jan-Henning
Published: April 2021

The cuticle exoskeleton plays a key role in facilitating the evolutionary success of insects. Since the mid of the last century, many different biomechanical properties of exoskeletons have been investigated, always utilizing the most sophisticated scientific methods available at the time. So far, information on the biomechanical properties of cuticle seems to be as diverse as the methods used to measure them. As a consequence, insect cuticle is often considered to exhibit the most complex and diverse biomechanical properties of any biological material. However, it remains unclear which role the respective measurement methods and sample treatments used in previous studies play in supporting this claim. This review provides a broad overview of examination techniques used to study biomechanical properties of insect exoskeletons and discusses their respective advantages and disadvantages in describing the properties of a complex material such as cuticle. Our meta-analysis of the present data confirms significant effects of the respective measurement methods, sample treatments and body parts on the obtained mechanical properties. Based on our findings, we highlight research gaps and point out important factors which should be taken into account in future studies on insect cuticle.
Echocardiographic assessment of mitral regurgitation: discussion of practical and methodologic aspects of severity quantification to improve diagnostic conclusiveness
Authors: Hagendorff Andreas , Knebel Fabian , Helfen Andreas , Stöbe Stephan , Haghi Dariush , Ruf Tobias , Lavall Daniel , Knierim Jan , Altiok Ertunc , Brandt Roland , Merke Nicolas , Ewen Sebastian
Published: April 2021

The echocardiographic assessment of mitral valve regurgitation (MR) by characterizing specific morphological features and grading its severity is still challenging. Analysis of MR etiology is necessary to clarify the underlying pathological mechanism of the valvular defect. Severity of mitral regurgitation is often quantified based on semi-quantitative parameters. However, incongruent findings and/or interpretations of regurgitation severity are frequently observed. This proposal seeks to offer practical support to overcome these obstacles by offering a standardized workflow, an easy means to identify non-severe mitral regurgitation, and by focusing on the quantitative approach with calculation of the individual regurgitant fraction. This work also indicates main methodological problems of semi-quantitative parameters when evaluating MR severity and offers appropriateness criteria for their use. It addresses the diagnostic importance of left-ventricular wall thickness, left-ventricular and left atrial volumes in relation to disease progression, and disease-related complaints to improve interpretation of echocardiographic findings. Finally, it highlights the conditions influencing the MR dynamics during echocardiographic examination. These considerations allow a reproducible, verifiable, and transparent in-depth echocardiographic evaluation of MR patients ensuring consistent haemodynamic plausibility of echocardiographic results.

Graphic abstract
The acetabular roof reinforcement plate for the treatment of displaced acetabular fractures in the elderly: results in 59 patients
Authors: Krappinger Dietmar , Resch Herbert , Lindtner Richard A. , Becker Johannes , Mitterer Marian , Freude Thomas
Published: April 2021

Introduction

Open reduction and internal fixation is considered the gold standard of treatment for displaced acetabular fractures in younger patients. For elderly patients with osteoporotic bone quality, however, primary total hip arthroplasty (THA) with the advantage of immediate postoperative mobilization might be an option. The purpose of this study was to evaluate the clinical and radiological outcomes of surgical treatment of displaced osteoporotic acetabular fractures using the acetabular roof reinforcement plate (ARRP) combined with THA.

Materials and methods

Between 2009 and 2019, 84 patients were operated using the ARRP combined with THA. Inclusion criteria were displaced osteoporotic fractures of the acetabulum with or without previous hemi- or total hip arthroplasty, age above 65 years, and pre-injury ability to walk at least with use of a walking frame. Of the 84 patients, 59 could be followed up after 6 months clinically and radiographically. Forty-nine (83%) were primary fractures and 10 (17%) periprosthetic acetabular fractures.

Results

The mean age was 80.5 years (range 65–98 years). The average time from injury to surgery was 8.5 days (range 1–28). Mean time of surgery was 167 min (range 100–303 min). Immediate postoperative full weight bearing (FWB) was allowed for 51 patients (86%). At the 6-month follow-up, all 59 patients except one showed bony healing and incorporation of the ARRP. One case developed a non-union of the anterior column. No disruption, breakage or loosening of the ARRP was seen. Additional CT scans performed in 18 patients confirmed bony healing. Twenty-six patients (44%) had regained their pre-injury level of mobility. Complications requiring revision surgery occurred in 8 patients. Five of them were suffering from a prosthetic head dislocation, one from infection, one from hematoma and one from a heterotopic ossification.

Conclusions

The ARRP has proven to provide sufficient primary stability to allow for immediate FWB in most cases and represents a valuable option for the surgical management of displaced acetabular fractures in this challenging patient group.
The epicondylar ratio can be reliably determined in both computed tomography and X-ray
Authors: Lutz Bernd , Polcikova Lucia , Faschingbauer Martin , Reichel Heiko , Bieger Ralf
Published: April 2021

Purpose

One of the key factors to the successful revision of total knee arthroplasty (rTKA) is the reconstruction of the joint line, which can be determined using the epicondylar ratio (ER). The measurement is established in X-ray and MRI. However, it is not known whether computed tomography (CT) allows a more reliable determination. The objective was to assess the reliability of the ER in CT and to determine the correlation between the ER in CT and a.p. X-ray of the knee.

Methods

The ER was determined on X-ray and CT images of a consecutive series of 107 patients, who underwent rTKA. Measurements were made by two blinded observes, one measured twice. The inter- and intraobserver agreement, as well as the correlation between the two methods, were quantified with the Intraclass Correlation Coefficient.

Results

The average lateral ER was 0.32 (± 0.04) in X-ray and 0.32 (± 0.04) in CT. On the medial side, the average ER was 0.34 (± 0.04) in X-ray and 0.35 (± 0.04) in CT. The interobserver agreement for the same imaging modality was lateral 0.81 and medial 0.81 in X-ray as well as lateral 0.74 and medial 0.85 in CT. The correlation between the two methods was lateral 0.81 and medial 0.79.

Conclusions

The ER can be reliably determined in X-ray and CT. Measurements of the two image modalities correlate. Prior to rTKA, the sole use of the X-ray is possible.
Pregnancy outcomes in women with a hemoglobinopathy trait: a multicenter, retrospective study
Authors: Kasparek Jan , Burkhardt Tilo , Hoesli Irene , Amstad Bencaiova Gabriela
Published: April 2021

Purpose

To determine the risk of adverse maternal and neonatal outcomes in pregnant women with a hemoglobinopathy trait.

Materials and methods

Retrospective cohort study was conducted to compare adverse maternal and neonatal outcomes between pregnant women with a hemoglobinopathy trait (study group; n = 172), and without a hemoglobinopathy trait (control group; n = 360). The medical data were extracted from clinical records of pregnant women attending antenatal care and delivering at the University Hospital Basel or University Hospital Zurich between 2015 and 2018.

Results

A total of 172 pregnant women with a hemoglobinopathy trait and 360 controls were recruited. Apart from fetal acidosis, the groups did not differ significantly in any variables of adverse neonatal outcomes. Whereas, among the maternal outcomes the rate of abortion, gestational diabetes mellitus, bacteriuria or urinary tract infection, intrahepatic cholestasis, abnormal placentation and anemia postpartum were significantly increased in women with a hemoglobinopathy trait.

Conclusion

In our study, a hemoglobinopathy trait increased the risk of adverse maternal outcomes but did not increase adverse neonatal outcomes.
Osteoid osteoma: which is the best mininvasive treatment option?
Authors: Parmeggiani Anna , Martella Claudia , Ceccarelli Luca , Miceli Marco , Spinnato Paolo , Facchini Giancarlo
Published: April 2021

Osteoid osteoma is the third most common benign bone tumor, with well-known clinical presentation and radiological features. Although surgical excision has been the only therapeutic option for a long time, to date it has been replaced by minimally invasive techniques, which proved satisfactory success rates and low complication occurrence. Therefore, the purpose of this literature review was to describe the main updates of these recent procedures in the field of interventional radiology, with particular attention paid to the results of the leading studies relating to the efficacy, complications, and recurrence rate. Nevertheless, this study aimed to analyze the peculiarities of each reported technique, with specific focus on the possible improvements and pitfalls. Results proved that all mininvasive procedures boast a high success rate with slight number of complications and a low recurrence rate. Radiofrequency ablation is still considered the gold standard procedure for percutaneous treatment of osteoid osteoma, and it has the possibility to combine treatment with a biopsy. Interstitial laser ablation’s advantages are the simplicity of use and a lower cost of the electrodes, while cryoablation allows real-time visualization of the ablated zone, increasing the treatment safety. Magnetic resonance-guided focused ultrasound surgery is the most innovative non-invasive procedure, with the unquestionable advantage to be radiation free.
The evolution of hierarchical structure building capacity for language and music: a bottom-up perspective
Authors: Asano Rie
Published: April 2021

A central property of human language is its hierarchical structure. Humans can flexibly combine elements to build a hierarchical structure expressing rich semantics. A hierarchical structure is also considered as playing a key role in many other human cognitive domains. In music, auditory-motor events are combined into hierarchical pitch and/or rhythm structure expressing affect. How did such a hierarchical structure building capacity evolve? This paper investigates this question from a bottom-up perspective based on a set of action-related components as a shared basis underlying cognitive capacities of nonhuman primates and humans. Especially, I argue that the evolution of hierarchical structure building capacity for language and music is tractable for comparative evolutionary study once we focus on the gradual elaboration of shared brain architecture: the cortico-basal ganglia-thalamocortical circuits for hierarchical control of goal-directed action and the dorsal pathways for hierarchical internal models. I suggest that this gradual elaboration of the action-related brain architecture in the context of vocal control and tool-making went hand in hand with amplification of working memory, and made the brain ready for hierarchical structure building in language and music.
Evaluation of an enrichment programme for a colony of long-tailed macaques (Macaca fascicularis) in a rescue centre
Authors: Albanese Valeria , Kuan Michela , Accorsi Pier Attilio , Berardi Roberta , Marliani Giovanna
Published: April 2021

Long-tailed macaques are highly social primates that are commonly used in biomedical research as animal models. The aim of this study was to evaluate the effects of different kinds of enrichment on the behaviour and faecal cortisol metabolite (FCM) level in a colony of ex-laboratory long-tailed macaques during a programme of rehabilitation. The research was carried out in three periods, divided into two sessions each. Every period was composed of one control session (SC) and one session characterised by one type of enrichment: feeding enrichment (FE), manipulative enrichment (ME), and the last session during which manipulative and feeding enrichment were provided every day but in a mixed way (MIX). The results showed that manipulative and mixed enrichments caused positive changes to the activity budget of the colony, with a decrease in abnormal behaviour rates and an increase in play compared with control sessions. The rate of affiliative behaviours and low rate of aggression were probably because the group was composed mostly of females and it was stable, with a well-defined hierarchy. The research underlines the importance of a well-studied enrichment programme for the welfare of captive animals, which should exploit species-specific motivations.
Effects of invasive wetland macrophytes on habitat selection and movement by freshwater turtles
Authors: Angoh Siow Yan Jennifer , Freeland Joanna , Paterson James , Rupasinghe Prabha Amali , Davy Christina M.
Published: April 2021

Invasive species can significantly impact native wildlife by structurally altering habitats and access to resources. Understanding how native species respond to habitat modification by invasive species can inform effective habitat restoration, avoiding inadvertent harm to species at risk. The invasive graminoids Phragmites australis australis (hereafter Phragmites) and Typha ×  glauca are increasingly dominating Nearctic wetlands, often outcompeting native vegetation. Previous research suggests that turtles may avoid invasive Phragmites when moving through their home ranges, but the mechanisms driving avoidance are unclear. We tested two hypotheses that could explain avoidance of invaded habitat: (1) that stands of invasive macrophytes (Phragmites and Typha x glauca) impede movement, and (2) that they provide inadequate thermal conditions for turtles. We quantified active-season movements of E. blandingii (n = 14, 1328 relocations) and spotted turtles (Clemmys guttata; n = 12, 2295 relocations) in a coastal wetland in the Laurentian Great Lakes. Neither hypothesis was supported by the data. Phragmites and mixed-species Typha stands occurred within the home ranges of mature, active E. blandingii and C. guttata, and were used similarly to most other available habitats, regardless of macrophyte stem density. Turtles using stands of invasive macrophytes did not experience restricted movements or cooler shell temperatures compared to other wetland habitat types. Control of invasive macrophytes can restore habitat heterogeneity and benefit native wetland species. However, such restoration work should be informed by the presence of at-risk turtles, as heavy machinery used for control or removal may injure turtles that use these stands as habitat.
$$\ell _{1}$$ Common Trend Filtering
Authors: Yamada Hiroshi , Bao Ruoyi
Published: April 2021

The$$\ell _{1}$$ℓ1trend filtering enables us to estimate a continuous piecewise linear trend of univariate time series. This filter and its variants have subsequently been applied in various fields, including astronomy, climatology, economics, electronics, environmental science, finance, and geophysics. Although the$$\ell _{1}$$ℓ1trend filtering can estimate a continuous piecewise linear trend of univariate time series, it cannot estimate a common continuous piecewise linear trend of multiple time series. This paper develops a statistical procedure that enables us to estimate it, which is a multivariate extension of the$$\ell _{1}$$ℓ1trend filtering. We provide an algorithm for estimating it and a clue to specify the tuning parameter of the procedure, both required for its application. We also (i) numerically illustrate how well the algorithm works, (ii) provide an empirical illustration, and (iii) introduce a generalization of our novel method.
Streaming changepoint detection for transition matrices
Authors: Plasse Joshua , Hoeltgebaum Henrique , Adams Niall M.
Published: April 2021

Sequentially detecting multiple changepoints in a data stream is a challenging task. Difficulties relate to both computational and statistical aspects, and in the latter, specifying control parameters is a particular problem. Choosing control parameters typically relies on unrealistic assumptions, such as the distributions generating the data, and their parameters, being known. This is implausible in the streaming paradigm, where several changepoints will exist. Further, current literature is mostly concerned with streams of continuous-valued observations, and focuses on detecting a single changepoint. There is a dearth of literature dedicated to detecting multiple changepoints in transition matrices, which arise from a sequence of discrete states. This paper makes the following contributions: a complete framework is developed for adaptively and sequentially estimating a Markov transition matrix in the streaming data setting. A change detection method is then developed, using a novel moment matching technique, which can effectively monitor for multiple changepoints in a transition matrix. This adaptive detection and estimation procedure for transition matrices, referred to as ADEPT-M, is compared to several change detectors on synthetic data streams, and is implemented on two real-world data streams – one consisting of over nine million HTTP web requests, and the other being a well-studied electricity market data set.
The impact of artisanal gold mining, ore processing and mineralization on water quality in Marmato, Colombia
Authors: Torrance Keith W. , Redwood Stewart D. , Cecchi Alessandro
Published: April 2021

Marmato, Colombia, has been an important centre of gold mining since before the first Spanish colonizers arrived in 1536. The Marmato deposit is hosted in a dacite and andesite porphyry stock as sheeted sulphide-rich veinlet systems. The district is currently experiencing a surge in both major mining projects and artisanal mining, driven by sustained high gold prices. Ore from small-scale and artisanal gold mining is processed in numerous small mills (entables) around Marmato, which impact surface water quality through the discharge of milled waste rock slurry, highly alkaline cyanide-treated effluent, and high dissolved metal loads. To investigate the impact of artisanal mining and ore processing, water samples were collected in January 2012 from streams around Marmato. The average dissolved metal concentrations in impacted streams were Zn, 78 mg L−1; Pb, 0.43 mg L−1; Cu, 403 µg L−1 Cd, 255 µg L−1; As, 235 µg L−1; Ni, 67 µg L−1; Co, 55 µg L−1; Sb, 7 µg L−1; and Hg, 42 ng L−1, exceeding World Health Organization drinking water guidelines. In addition, arsenic speciation was conducted in-situ and indicated that 91–95% of inorganic arsenic species is in the form of As(V). Spatial analysis of the data suggests that entables processing ore for artisanal miners are the main contributor to water pollution, with high sediment loads, alkalinity and elevated concentrations of dissolved arsenic, cadmium, mercury and lead, caused by the processing of gold-bearing sulphides in the entables. Geochemical data from surface water were compared to a comprehensive data set of whole rock analyses from drill core and channel samples from the deposit, indicating that the deposit is significantly enriched in gold, silver, lead, zinc, arsenic, antimony, and cadmium compared to crustal averages, which is reflected in the surface water geochemistry. However, elevated mercury levels in surface water cannot be explained by enrichment of mercury in the deposit and strongly suggest that mercury is being added to concentrates during ore processing to amalgamate fine gold.