bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of hyperarticulation on speech comprehension under adverse listening conditions
Authors: Kangatharan Jayanthiny , Uther Maria , Gobet Fernand
Published: September 2021

Comprehension assesses a listener’s ability to construe the meaning of an acoustic signal in order to be able to answer questions about its contents, while intelligibility indicates the extent to which a listener can precisely retrieve the acoustic signal. Previous comprehension studies asking listeners for sentence-level information or narrative-level information used native listeners as participants. This is the first study to look at whether clear speech properties (e.g. expanded vowel space) produce a clear speech benefit at the word level for L2 learners for speech produced in naturalistic settings. This study explored whether hyperarticulated speech was more comprehensible than non-hyperarticulated speech for both L1 British English speakers and early and late L2 British English learners in quiet and in noise. Sixteen British English listeners, 16 native Mandarin Chinese listeners as early learners of L2 and 16 native Mandarin Chinese listeners as late learners of L2 rated hyperarticulated samples versus non-hyperarticulated samples in form of words for comprehension under four listening conditions of varying white noise level (quiet or SNR levels of + 16 dB, + 12 dB or + 8 dB) (3 × 2× 4 mixed design). Mean ratings showed all three groups found hyperarticulated speech samples easier to understand than non-hyperarticulated speech at all listening conditions. Results are discussed in terms of other findings (Uther et al., 2012) that suggest that hyperarticulation may generally improve speech processing for all language groups.
Prosthetic rehabilitation of maxillary lateral incisors agenesis using dental mini-implants: a multicenter 10-year follow-up
Authors: Lacarbonara M. , Cazzolla A.P. , Lacarbonara V. , Lo Muzio L. , Ciavarella D. , Testa N.F. , Crincoli V. , Di Venere D. , De Franco A. , Tripodi D. , Grassi F.R. , Capogreco M.
Published: September 2021

Objectives

Implants are used to replace congenitally missing lateral incisors but often the space across the alveolar crest is too narrow to permit their use. This multicenter study (Dental Clinic of the University of Foggia, Odontostomatology Clinic of the University of L’Aquila) evaluated the efficacy of mini-implants in cases of maxillary lateral incisor agenesis with severe osseous atrophy in 10-year follow-up.

Materials and methods

Forty-seven mini-implants have been inserted in 35 patients affected by lateral incisors agenesis (23 single and 12 bilateral ageneses). All patients underwent orthodontic opening of the space of the upper lateral incisors. After the insertion of the implants, the immediate, non-functional loading, positioning of crowns, presence of pain during percussion and mini-implant function, horizontal and vertical movement when a force of 5 N was applied, ridge loss, and plaque index have been evaluated 1 month after loading, 1 year after loading, and then every 5 years in the following 10 years. Little’s test was used to evaluate the assumption that data of loss to follow-up implants are missing completely at random (MCAR) and that a complete-case scenario could be adopted. Wilcoxon test was carried out to look statistically significant differences between the various parameters resulting in the complete-case scenario and those assumed for the worst scenario. The software R (v. 3.6.1, 2019) was employed to perform the statistical analysis.

Results

The results obtained over 10 years range from 89% of success rate in a worst-case scenario to the 100% using a complete-case analysis with satisfactory values of marginal bone resorption and good conditions of the peri-implant tissue. Ten-year follow-up using complete-case analysis shows survival rates of 100% for implants with no signs of peri-implantitis, stability of the marginal bone levels and soft tissue around the dental implants.

Conclusions

The data collected show very good implant stability, absence of progressive peri-implantitis, and satisfactory aesthetical results in time (no signs of infraocclusion).

Clinical relevance

Mini-implants can be considered a valid and stable over time solution in the restorative treatment of maxillary lateral incisors agenesis.
Fate of turbid glacial inflows in a hydroelectric reservoir
Authors: Robb Daniel M. , Pieters Roger , Lawrence Gregory A.
Published: September 2021

Turbidity from glacial meltwater limits light penetration with potential ecological consequences. Using profiles of temperature, conductivity, and turbidity, we examine the physical processes driving changes in the epilimnetic turbidity of Carpenter Reservoir, a long and narrow, glacier-fed reservoir in southwest British Columbia, Canada. Following the onset of permanent summer stratification, the relatively dense inflows plunged into the hypolimnion, and despite the high glacial load entering the reservoir, the epilimnion cleared due to particle settling. Using a one-dimensional (longitudinal) diffusion equation for a decaying substance to describe the variation in epilimnetic turbidity, we obtain two nondimensional parameters: the epilimnetic inflow parameter,$$\mathcal {I}$$I, a measure of the turbidity flux into the epilimnion; and the dispersion parameter,$${\mathcal {D}}$$D, a measure of longitudinal dispersion. In the case of Carpenter Reservoir:$$\mathcal {I}\ll 1$$I≪1, indicating that turbidity declines over the summer; and$${\mathcal {D}}\ll 1$$D≪1, indicating a strong gradient in turbidity along the epilimnion. Using our theoretical formulation of epilimnetic turbidity variations in conjunction with monthly field surveys, we compute the particle settling velocity ($${\sim}{0.25}\,{\hbox {m}\,\hbox {d}^{-1}}$$∼0.25md-1), the longitudinal dispersion coefficient (50–70 $${\hbox {m}^{2}\,\hbox {s}^{-1}}$$m2s-1), and the flux of turbid water into the epilimnion ($${\sim }1{\%}$$∼1%of the total inflow). Our approach is applicable to other reservoirs and can be used to investigate changes in turbidity in response to changes in$$\mathcal {I}$$Iand$${\mathcal {D}}$$D.
Non-therapeutic male circumcision in infancy or childhood and risk of human immunodeficiency virus and other sexually transmitted infections: national cohort study in Denmark
Authors: Frisch Morten , Simonsen Jacob
Published: September 2021

Whether male circumcision in infancy or childhood provides protection against the acquisition of human immunodeficiency virus (HIV) or other sexually transmitted infections (STIs) in adulthood remains to be established. In the first national cohort study to address this issue, we identified 810,719 non-Muslim males born in Denmark between 1977 and 2003 and followed them over the age span 0–36 years between 1977 and 2013. We obtained information about cohort members’ non-therapeutic circumcisions, HIV diagnoses and other STI outcomes from national health registers and used Cox proportional hazards regression analyses to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) associated with foreskin status (i.e., circumcised v. genitally intact). During a mean of 22 years of follow-up, amounting to a total observation period of 17.7 million person-years, 3375 cohort members (0.42%) underwent non-therapeutic circumcision, and 8531 (1.05%) received hospital care for HIV or other STIs. Compared with genitally intact males, rates among circumcised males were not statistically significantly reduced for any specific STI. Indeed, circumcised males had a 53% higher rate of STIs overall (HR = 1.53, 95% CI: 1.24–1.89), and rates were statistically significantly increased for anogenital warts (74 cases in circumcised males v. 7151 cases in intact males, HR = 1.51; 95% CI: 1.20–1.90) and syphilis (four cases in circumcised males v. 197 cases in intact males, HR = 3.32; 95% CI: 1.23–8.95). In this national cohort study spanning more than three decades of observation, non-therapeutic circumcision in infancy or childhood did not appear to provide protection against HIV or other STIs in males up to the age of 36 years. Rather, non-therapeutic circumcision was associated with higher STI rates overall, particularly for anogenital warts and syphilis.
Critical phenomenology and psychiatry
Authors: Zahavi Dan , Loidolt Sophie
Published: September 2021

Whereas classical Critical Theory has tended to view phenomenology as inherently uncritical, the recent upsurge of what has become known as critical phenomenology has attempted to show that phenomenological concepts and methods can be used in critical analyses of social and political issues. A recent landmark publication, 50 Concepts for Critical Phenomenology, contains no reference to psychiatry and psychopathology, however. This is an unfortunate omission, since the tradition of phenomenological psychiatry—as we will demonstrate in the present article by surveying and discussing the contribution of Jaspers, Minkowski, Laing, Basaglia, and Fanon—from the outset has practiced critical thinking, be it at the theoretical, interpersonal, institutional, or political level. Fanon is today a recognized figure in critical phenomenology, even if his role in psychiatry might not yet have been appreciated as thoroughly as his anticolonial and antiracist contributions. But as we show, he is part of a long history of critical approaches in psychopathology and psychiatry, which has firm roots in the phenomenological tradition, and which keeps up its critical work today.
Nonconsensual neurocorrectives, bypassing, and free action
Authors: De Marco Gabriel
Published: September 2021

As neuroscience progresses, we will not only gain a better understanding of how our brains work, but also a better understanding of how to modify them, and as a result, our mental states. An important question we are faced with is whether the state could be justified in implementing such methods on criminal offenders, without their consent, for the purposes of rehabilitation and reduction of recidivism; a practice that is already legal in some jurisdictions. By focusing on a prominent type of view of free action, which I call bypassing views, this paper evaluates how such interventions may negatively impact the freedom of their subjects. The paper concludes that there will be a tension between the goals of rehabilitation and reduction of recidivism, on the one hand, and the negative impact such interventions may have on free action, on the other. Other things equal, the better that a particular intervention is at achieving the former, the more likely it is to result in the latter.
Belowground responses of bacterial communities to foliar SA application over four plant generations
Authors: Zhang Jing , Klinkhamer Peter G. L. , Vrieling Klaas , Martijn Bezemer T.
Published: September 2021

Background and aims

Jacobaea vulgaris plants grow better in sterilized than in live soil. Foliar application of SA mitigates this negative effect of live soil on plant growth. To examine what causes the positive effect of SA application on plant growth in live soils, we analyzed the effects of SA application on the composition of active rhizosphere bacteria in the soil.

Methods

We studied the composition of the microbial community over four consecutive plant cycles (generations), using mRNA sequencing of the microbial communities in the rhizosphere of J. vulgaris. We initiated the experiment with an inoculum of live soil collected from the field, and at the start of each subsequent plant cycle, we inoculated a small part of the soil from the previous plant cycle into sterile bulk soil.

Results

Application of SA did not significantly increase or decrease the Shannon diversity at genus level within each generation, but several specific genera were enriched or depleted after foliar SA application. The composition of bacterial communities in the rhizosphere significantly differed between plant cycles (generations), but application of SA did not alter this pattern. In the first generation no genera were significantly affected by the SA treatment, but in the second, third and fourth generations, specific genera were significantly affected. 89 species out of the total 270 (32.4%) were present as the “core” microbiome in all treatments over four plant cycles.

Conclusions

Overall, our study shows that the composition of bacterial genera in the rhizosphere significantly differed between plant cycles, but that it was not strongly affected by foliar application of SA on J. vulgaris leaves. Further studies should examine how activation of the SA signaling pathway in the plant changes the functional genes of the rhizosphere bacterial community.
Main challenges to international student mobility in the European arena
Authors: López-Duarte Cristina , Maley Jane F. , Vidal-Suárez Marta M.
Published: September 2021

This study analyses international student mobility (ISM) in Europe since the 1999 Bologna Declaration. International mobility of higher education students is both a driver and a consequence of the Bologna Process and emerges as a relevant issue in a wide range of research areas. This literature review develops a qualitative content analysis of the set of high-performance articles published between 2000 and 2018 and identified through a wide range of bibliometric tools: direct (first generation) citation counts; indirect or accumulated impact; early influence; adjusted impact with respect to year of publication, type of document, and discipline; and alternative metrics that measure interactions in the internet and social media. The content analysis focuses on the pending achievements and main challenges to ISM, among them: attracting non-European students to whole degree programs, the need for actual and further convergence in programs and systems to ensure real compatibility, the impact of HE ISM on the promotion of the European citizenship and consciousness, the sharp imbalance between credit and degree mobility, the need to strengthen the link between ISM and employability, the existing social selectivity in European ISM, the frequent social segregation problems faced by international students.
Enhancing students’ critical thinking skills: is comparing correct and erroneous examples beneficial?
Authors: van Peppen Lara M. , Verkoeijen Peter P. J. L. , Heijltjes Anita E. G. , Janssen Eva M. , van Gog Tamara
Published: September 2021

There is a need for effective methods to teach critical thinking (CT). One instructional method that seems promising is comparing correct and erroneous worked examples (i.e., contrasting examples). The aim of the present study, therefore, was to investigate the effect of contrasting examples on learning and transfer of CT-skills, focusing on avoiding biased reasoning. Students (N = 170) received instructions on CT and avoiding biases in reasoning tasks, followed by: (1) contrasting examples, (2) correct examples, (3) erroneous examples, or (4) practice problems. Performance was measured on a pretest, immediate posttest, 3-week delayed posttest, and 9-month delayed posttest. Our results revealed that participants’ reasoning task performance improved from pretest to immediate posttest, and even further after a delay (i.e., they learned to avoid biased reasoning). Surprisingly, there were no differences in learning gains or transfer performance between the four conditions. Our findings raise questions about the preconditions of contrasting examples effects. Moreover, how transfer of CT-skills can be fostered remains an important issue for future research.
MiR-615 Agomir Encapsulated in Pluronic F-127 Alleviates Neuron Damage and Facilitates Function Recovery After Brachial Plexus Avulsion
Authors: Chen Kangzhen , Ding Lu , Shui Hua , Liang Yinru , Zhang Xiaomin , Wang Tao , Li Linke , Liu Shuxian , Wu Hongfu
Published: September 2021

Brachial plexus avulsion (BPA) is a devastating traumatic peripheral nerve injury complicated with paralysis of the upper extremity. We previously reported that leucine-rich repeat and immunoglobulin-like domain-containing NOGO receptor-interacting protein 1 (LINGO-1) has a potent role in inhibiting neuron survival and axonal regeneration after the central nervous system (CNS) damage and miR-615 is a potential microRNA (miRNA) negatively regulated LINGO-1. However, the effect of miR-615 in BPA remains to be elucidated. Accumulating evidence indicates that pluronic F-127 (PF-127) hydrogel could serve as a promising vehicle for miRNA encapsulation. Thus, to further explore the potential role of hydrogel-miR-615 in BPA-reimplantation, the present study established the BPA rat model and injected miR-615 agomir encapsulated by PF-127 hydrogel into the reimplantation site using a microsyringe. In this study, results indicated that hydrogel-miR-615 agomir effectively alleviated motoneuron loss by LINGO-1 inhibition, promoted musculocutaneous nerve regeneration and myelination, reduced astrocytes activation, promoted angiogenesis and attenuated peripheral amyotrophy, leading to improved motor functional rehabilitation of the upper extremity. In conclusion, our findings demonstrate that miR-615-loaded PF-127 hydrogel may represent a novel therapeutic strategy for BPA treatment.
Optimal design of the Sermo Fault deformation monitoring network using sensitivity criteria based on geological information
Authors: Yulaikhah  , Pramumijoyo Subagyo , Widjajanti Nurrohmat , Widagdo Asmoro
Published: September 2021

The Sermo Reservoir is located in Kulon Progo District, Special Region of Yogyakarta, Indonesia. It plays a vital role in providing water to its surrounding communities. According to the geological structure of this area, a fault exists near the Ngrancah River and passes through the reservoir’s inundation. At present, a network consists of 15 Global Navigation Satellite System (GNSS) monitoring stations spread around the Sermo Fault to monitor its deformation. However, this network was designed without consideration of geological parameters. This study aimed to design an optimal deformation monitoring network of the Sermo Fault by taking into account geological information and evaluate the existing network, specifically, the optimal distance for the station to the fault plane. Geological surveys were carried out to obtain information regarding the type and characteristics of the fault. This information was used as one of the parameters in the optimization design, using sensitivity criteria, of a network to monitor for the optimal distance between the observation station and fault. Using the strike-slip fault model, the optimal distance obtained was from 4.5 to 8.5 km from the fault plane. The existing stations of the Sermo Fault deformation monitoring network are about 0.07–3.3 km away from the fault. Therefore, the network is insufficiently sensitive and needs to be developed by adding stations that are more than 4.5 km away from the fault. This study designed an alternative network by rearranging the stations’ location to obtain a better configuration and sensitivity.
Occurrence and characterisation of naphthenic acid fraction components in oil residues and sediments stranded on the shoreline of Chedabucto Bay, Nova Scotia, Canada
Authors: Yang Zeyu , Zhang Gong , Yang Chun , Shah Keval , Hollebone Bruce P. , Laforest Sonia , Lambert Patrick , Brown Carl E. , Situ Jane , Verkuyl Alexandra
Published: September 2021

In June 2016, oil residues and sediment samples were collected from the shoreline of Chedabucto Bay, Nova Scotia, Canada, at sites affected by the 1970 Arrow oil spill. This study aimed to investigate the occurrence, fate, and behaviour of oil components 45 years post-spill by analysing polar naphthenic acid fraction components (NAFCs) through high-performance liquid chromatography–high-resolution mass spectrometry (HPLC–HRMS). In all samples, the most abundant NAFC species were those having only oxygen as the heteroatom (Oo species, o indicating the number of oxygen atoms, from 1 to 8) and a high degree of saturation. NAFC species only containing two oxygen atoms (O2) accounted for 50–70% of all Oo species. The abundance of all remaining species was negligible compared with Oo species. NAFCs in most Arrow oil residues had higher levels of oxygen species than the oil remaining stored in the sunken tanker. Environmental sediment samples collected from near a marina away from the spill site contained a dominant biological, whereas all Arrow oil residues were mainly composed of NAFCs that are characteristic of petroleum. The abundance of NAFCs in the Arrow oil residues varied between sites, confirming that site-specific environmental conditions play a major role in controlling the fate and behaviour of oil components, including NAFCs.
Simulation of the impact of climate change on runoff and drought in an arid and semiarid basin (the Hablehroud, Iran)
Authors: Lotfirad Morteza , Adib Arash , Salehpoor Jaber , Ashrafzadeh Afshin , Kisi Ozgur
Published: September 2021

This study evaluates the impact of climate change (CC) on runoff and hydrological drought trends in the Hablehroud river basin in central Iran. We used a daily time series of minimum temperature (Tmin), maximum temperature (Tmax), and precipitation (PCP) for the baseline period (1982–2005) analysis. For future projections, we used the output of 23 CMIP5 GCMs and two scenarios, RCP 4.5 and RCP 8.5; then, PCP, Tmin, and Tmax were projected in the future period (2025–2048). The GCMs were weighed based on the K-nearest neighbors algorithm. The results indicated a rising temperature in all months and increasing PCP in most months throughout the Hablehroud river basin's areas for the future period. The highest increase in the Tmin and Tmax in the south of the river basin under the RCP 8.5 scenario, respectively, was 1.87 °C and 1.80 °C. Furthermore, the highest reduction in the PCP was 54.88% in August under the RCP 4.5 scenario. The river flow was simulated by the IHACRES rainfall-runoff model. The annual runoff under the scenarios RCP 4.5 and RCP 8.5 declined by 11.44% and 13.13%, respectively. The basin runoff had a downward trend at the baseline period; however, it will have a downward trend in the RCP 4.5 scenario and an upward trend in the RCP 8.5 scenario for the future period. This study also analyzed drought by calculating the streamflow drought index for different time scales. Overall, the Hablehroud river basin will face short-term and medium-term hydrological drought in the future period.
Methodology and algorithm to correct the thermal neutron porosity for the effect of rare elements and rock minerals with high neutron absorption probability
Authors: Oraby Moustafa
Published: September 2021

The thermal neutron porosity is routinely acquired in almost every well. When combined with the density, gamma ray and resistivity logs, the basic petrophysical parameters of a reservoir are evaluated. The design of the thermal neutron tool is simple, but its interpretation is complex and affected by the formation constituents. The most challenging situation occurs when the formation contains elements with high absorption probability of the thermal neutrons. The existence of such elements changes the neutron transport parameters and results in a false increase in the measured porosity. The problem is reported by many users throughout the years. In 1993, higher thermal neutron porosity is reported due to the existence of an iron-rich mineral, Siderite, in the Nazzazat and Baharia formations in Egypt. Siderite and all iron-rich minerals have high thermal neutrons absorption probability. Recently, in 2018, high thermal neutron porosity in Unayzah field in Saudi Arabia is also reported due to the existence of few parts per million of gadolinium. Gadolinium is a rare element that has high probability of thermal neutron absorption. Currently, none of the existing commercial petrophysics software(s) have modules to correct the thermal neutron porosity for such effects. This represents a challenge to the petrophysicists to properly calculate the actual reservoir porosity. In this paper, the effects of the rare elements and other minerals with high thermal neutron absorption probability on the thermal neutron porosity are discussed, and a correction methodology is developed and tested. The methodology is based on integrating the tool design and the physics of the neutron transport to perform the correction. The details of the correction steps and the correction algorithm are included, tested and applied in two fields.
Aeromagnetic and electrical resistivity mapping for groundwater development around Ilesha schist belt, southwestern Nigeria
Authors: Okpoli Cyril Chibueze , Akinbulejo Blessing omobolanle
Published: September 2021

Aeromagnetic and vertical electrical sounding around Ijano, southwestern Nigeria, was investigated for groundwater potential. Aeromagnetic dataset and vertical electrical sounding were acquired and used to investigate the study area. Oasis Montaj, Microsoft Excel and Arc GIS were used to present the results in maps, images and profiles. In order to map out the geological structures of the study area, magnetic image enhancing filters applied to the total magnetic intensity using Geosoft (Oasis Montaj) are reduction to equator, vertical derivative, total horizontal derivative and upward continuation. These filters helped define the lithological boundaries, geological structures, faults, folds and contacts. The lineament of aeromagnetic map was generated from derived field intensity gradients and solutions of Euler deconvolution carried out on the aeromagnetic data using structural index of 0.5 and 1. The processed image shows the lineaments trends majorly towards NE–SW directions. From these combined results of the study area, consistent aeromagnetic lineament map was generated showing the probable positions and trends of the suspected fractured/faulted zone as well as other basement structures. Hydro-lineament density maps based on lineament were produced from the generalized structure trends in the area. The result from the depth sounding data interpretation indicates three curve types which are H, HA and KH, where curve type H has the highest occurrence. The results from the vertical electrical sounding data revealed that the areas with the highest hydro-lineament density are good for groundwater prospect and development. The study has led to the delineation of areas where groundwater occurrences are most promising for sustainable supply, suggesting that an area with high concentrations of lineament density has a high tendency for groundwater prospecting. The results from the study show that the aeromagnetic technique is capable of extracting lineament trends in an inaccessible tropical forest.
The effect of carbonate rock wettability on the performance of low salinity waterflooding: an experimental approach
Authors: Zekri Abdulrazag , Nantongo Hildah , Boukadi Fathi
Published: September 2021

While the “low salinity waterflooding” (LSWF) has been praised for enhancing oil recovery from different core rocks, the performance of the technique in different wettability environments remains unclear. The consensus is that LSWF does not work well in water-wet carbonate oil reservoirs. The main research objective was to determine the effect of LSWF on the displacement efficiency (DE) in different wettability environments. Carbonate core flooding experiments on rocks with different wettabilities were performed at in-situ reservoir conditions using seawater as a “base water”. Seawater was sequentially diluted 10 to 50 times and spiked 2 and 6 times with sulfate. Following sequential flooding with four different waters, the DEs were measured for different wettabilities. Five different sequential brine floodings were performed on carbonate rocks. Results indicated that optimum low salinity water is a function of system wettability. Seawater (≈ 50,000 ppm) is the optimum brine for oil-wet and intermediate-wettability systems. Sequential flooding consisting of seawater followed by diluted seawater in a water-wet system yielded the highest DE of 88%. Besides, low-salinity brine followed by sulfate performed better in a water-wet environment than in oil- and intermediate-wettability systems.
Can preoperative 25-hydroxyvitamin D levels predict transient hypocalcemia after total thyroidectomy?
Authors: Saibene Alberto Maria , Rosso Cecilia , Felisati Giovanni , Pipolo Carlotta , De Leo Simone , Lozza Paolo , Cozzolino Mario Gennaro , De Pasquale Loredana
Published: September 2021

Transient postoperative hypocalcemia is a common complication after total thyroidectomy. Evidence on contributing metabolic factors is contradictory. Our work aims to define the role of preoperative 25-hydroxyvitaminD levels in developing transient postoperative hypocalcemia. 183 consecutive patients who underwent total thyroidectomy at our institution (May 2017–December 2019) were included in the retrospective study. We reported gender, age, estimated glomerular filtration rate, creatinine, preoperative 25-hydroxyvitaminD, serum pre- and postoperative calcium, pre- and postoperative PTH levels and transient postoperative hypocalcemia occurrences. We compared variables both among patients with and without transient postoperative hypocalcemia and between patients with different 25-hydroxyvitaminD levels (< 10 ng/ml deficitary; 11–30 ng/ml insufficient; > 30 ng/ml, normal). A binomial logistic regression model evaluating the risk for transient postoperative hypocalcemia was elaborated. Patients with transient postoperative hypocalcemia had lower levels of postoperative PTH (p < 0.001) and more frequently normal or deficitary 25-hydroxyvitaminD levels (p = 0.05). When comparing patients according to their 25-hydroxyvitaminD levels, insufficiency was associated with a lower rate of transient postoperative hypocalcemia (p = 0.05); deficiency was associated with higher preoperative PTH (p = 0.021), postoperative PTH (p = 0.043) and estimated glomerular filtration rate (p = 0.031) and lower serum creatinine (p = 0.014). In the regression model higher preoperative PTH (OR = 1.011, p = 0.041) and 25-hydroxyvitaminD deficiency (OR = 0.343, p = 0.011) significantly predicted transient postoperative hypocalcemia. Data analysis revealed a correlation between transient postoperative hypocalcemia and 25-hydroxyvitaminD levels: our work points towards the possibility to stratify the risk of transient postoperative hypocalcemia according to patients’ preoperative 25-hydroxyvitaminD status.
Residual-stress relaxation mechanism and model description of 5052H32 Al alloy spun ellipsoidal heads during annealing treatment
Authors: Lin Yong-Cheng , Zhu Jiang-Shan , Chen Jia-Yang , Wang Jun-Quan
Published: September 2021

Marginal-restraint mandrel-free spinning is an advanced technology for manufacturing ellipsoidal heads with large diameter-thickness ratios. Nevertheless, the spinning-induced residual stress, which greatly influences the in-service performance of spun heads, should be removed. In this study, the effects of annealing on the residual-stress relaxation behavior of 5052H32 aluminum alloy spun heads were investigated. It is found that the residual stress first rapidly decreases and then remains steady with the increase in annealing time at the tested annealing temperatures. The relaxation of the residual stress becomes increasingly obvious with the increase in annealing temperature. When the annealing temperature is less than 220 °C, there are no obvious changes in grain size. Moreover, the spinning-induced dislocations are consumed by the static recovery behavior, which decreases the residual stress during annealing. When the annealing temperature is approximately 300 °C, the broken grains transform into equiaxed grains. In addition, static recrystallization and recovery behaviors occur simultaneously to promote the relaxation of the residual stress. Considering the different stress relaxation mechanisms, a model based on the Zener-Wert-Avrami equation was established to predict the residual-stress relaxation behavior. Finally, the optimized annealing temperature and time were approximately 300 °C and 30 min, respectively.
MOF-Derived ZnS Nanodots/Ti3C2Tx MXene Hybrids Boosting Superior Lithium Storage Performance
Authors: Cao Bin , Liu Huan , Zhang Xin , Zhang Peng , Zhu Qizhen , Du Huiling , Wang Lianli , Zhang Rupeng , Xu Bin
Published: September 2021

ZnS has great potentials as an anode for lithium storage because of its high theoretical capacity and resource abundance; however, the large volume expansion accompanied with structural collapse and low conductivity of ZnS cause severe capacity fading and inferior rate capability during lithium storage. Herein, 0D-2D ZnS nanodots/Ti3C2Tx MXene hybrids are prepared by anchoring ZnS nanodots on Ti3C2Tx MXene nanosheets through coordination modulation between MXene and MOF precursor (ZIF-8) followed with sulfidation. The MXene substrate coupled with the ZnS nanodots can synergistically accommodate volume variation of ZnS over charge–discharge to realize stable cyclability. As revealed by XPS characterizations and DFT calculations, the strong interfacial interaction between ZnS nanodots and MXene nanosheets can boost fast electron/lithium-ion transfer to achieve excellent electrochemical activity and kinetics for lithium storage. Thereby, the as-prepared ZnS nanodots/MXene hybrid exhibits a high capacity of 726.8 mAh g−1 at 30 mA g−1, superior cyclic stability (462.8 mAh g−1 after 1000 cycles at 0.5 A g−1), and excellent rate performance. The present results provide new insights into the understanding of the lithium storage mechanism of ZnS and the revealing of the effects of interfacial interaction on lithium storage performance enhancement.
Archaeoseismological study of the Cherichira aqueduct bridge, Kairouan, Tunisia
Authors: Hinzen Klaus-G. , Meghraoui Mustapha , Bahrouni Nejib , Houla Yassine , Reamer Sharon K.
Published: September 2021

In the past, several destructive earthquakes have occurred in the North African Atlas Mountain ranges located along the Africa–Eurasia plate boundary. Although the region is rich with impressive archaeological sites, including those in modern Tunisia, few comprehensive archaeoseismological studies have been conducted. Historic sources account at least three damaging earthquakes in the Kairouan area in central Tunisia between AD 859 and 1041. Little is known about which faults triggered these earthquakes or the size of these events. The water supply of the city of Kairouan depended on a 32-km-long aqueduct with a large bridge (now partially collapsed) at the confluence of the de Mouta and Cherichira rivers. The original bridge of Roman construction was retrofitted twice during the Aghlabid period (AD 800–903) and probably in AD 995 during the Fatimid period. The ruined section of the bridge shows damage which might be related to the AD 859 earthquake shaking. Here, we present a detailed study of the history, the status and the damage of the Cherichira aqueduct bridge using previous historic accounts and written works, a 3D laser scan model, local geological and seismological characteristics, and include results of radiocarbon dating and a timeline of events. In addition to earthquake ground motions, we consider severe flash floods on the bridge as a potential cause of the damage. We estimate the severity of such flash floods and develop a model with 18 earthquake scenarios on local reverse and strike-slip faults with magnitudes between MW6.1 and 7.2. While a few damage patterns might be indicative of flooding, most damage can be attributed to earthquakes. It is highly probable that the earthquake in AD 859 caused enough damage to the Aghlabid bridge to render it dysfunctional; however, to resolve the question of whether another earthquake in AD 911 or 1041 caused the complete destruction of the previously retrofitted aqueduct by the Fatimids requires dating of additional sections of the bridge.
Robust flocking for non-identical second-order nonlinear multi-agent systems
Authors: Li Xiuxian , Su Housheng , Li Li
Published: September 2021

This paper investigates the robust flocking problem for second-order nonlinear systems with a leader and external disturbances. In contrast with most of second-order systems in the literature, the intrinsic dynamics here are nonlinear and non-identical that depend not only on the velocity but also on the position, which is more realistic. Moreover, the interaction topology is undirected and switching. Provided that the leader’s velocity may be constant or time-varying, two distributed flocking control laws have been proposed for two cases to make the differences of the velocities between all followers and the leader approach to zero asymptotically. The proposed distributed flocking control laws are both model-independent which results in the effectiveness of the controllers to cope with the different intrinsic dynamics of the followers and the leader under some assumptions on boundedness of several states. An example is given to illustrate the validity of the theoretical results.
Emerging geo-data sources to reveal human mobility dynamics during COVID-19 pandemic: opportunities and challenges
Authors: Li Xiao , Xu Haowen , Huang Xiao , Guo Chenxiao , Kang Yuhao , Ye Xinyue
Published: September 2021

Effectively monitoring the dynamics of human mobility is of great importance in urban management, especially during the COVID-19 pandemic. Traditionally, the human mobility data is collected by roadside sensors, which have limited spatial coverage and are insufficient in large-scale studies. With the maturing of mobile sensing and Internet of Things (IoT) technologies, various crowdsourced data sources are emerging, paving the way for monitoring and characterizing human mobility during the pandemic. This paper presents the authors’ opinions on three types of emerging mobility data sources, including mobile device data, social media data, and connected vehicle data. We first introduce each data source’s main features and summarize their current applications within the context of tracking mobility dynamics during the COVID-19 pandemic. Then, we discuss the challenges associated with using these data sources. Based on the authors’ research experience, we argue that data uncertainty, big data processing problems, data privacy, and theory-guided data analytics are the most common challenges in using these emerging mobility data sources. Last, we share experiences and opinions on potential solutions to address these challenges and possible research directions associated with acquiring, discovering, managing, and analyzing big mobility data.
Exploring the Process of Business Ecosystem Emergence from Value Chains: Insights from the Chinese Mobile Phone Industry
Authors: Shi Xianwei , Luo Yuankun , Hou Hong , Rong Ke , Shi Yongjiang
Published: September 2021

A business ecosystem is a community of multiple co-evolving actors with interdependent product offerings organized around a specific value proposition. While the extant literature focuses on these two structural elements of ecosystems that existed ex ante, we challenge this notion with our core discovery that ecosystem actors emerge in an ex post dynamic process. With a longitudinal qualitative study of the vertically disintegrated part of the Chinese mobile phone industry, we develop a two-dimensional process model of ecosystem emergence, namely the temporal dimension that delineates three processal stages of ecosystem emergence and the spatial dimension that highlights an architectural pattern of reciprocities between value chain and resource pool to enable the ecosystem emergence. We also offer inter-temporal enabling conditions during ecosystem evolution. These findings enable us to complement the ecosystem literature by elaborating the antecedents, outcomes, and enabling conditions of ecosystem emergence in relation to multiple types of ecosystem actors. We also shed light on the value chain (re-)configuring process which derives from the reciprocity between value chains and ecosystem resources.
Changing Water Resources Under El Niño, Climate Change, and Growing Water Demands in Seasonally Dry Tropical Watersheds
Authors: Hund Silja V. , Grossmann Iris , Steyn Douw G. , Allen Diana M. , Johnson Mark S.
Published: September 2021

The wet‐dry tropics of Central America are characterized by long dry seasons, during which communities often struggle for water. High interannual rainfall variability, driven in parts by the El Niño Southern Oscillation (ENSO), increases these challenges. Further, climate change projections indicate that the region will likely become drier. However, research on impacts on water resources at the watershed scale is limited in the region—yet this information is essential for water managers. Therefore, in this research, we quantified the potential impacts of ENSO and four different climate change scenarios on water resources in two watersheds in the wet‐dry tropics of Guanacaste, Costa Rica, using a hydrological model (Water Evaluation and Planning Tool [WEAP]). Given that the watersheds are human used, we also explored different water demand scenarios. Modeling results indicated that an extreme El Niño can reduce groundwater recharge and streamflow by ∼60% relative to ENSO neutral. For 2075–2100, modeling results indicated that while potential evapotranspiration increases, actual evapotranspiration decreases due to limited water availability. Further, climate change may lead to reductions of mean annual streamflow and groundwater recharge by 40%–45% and 26%–28%, respectively, in comparison to the historical baseline. Importantly, high population growth could further hasten potentially irreversible groundwater storage declines. On the other hand, reduction of per‐capita water demand could slow down, or even reverse, the decline of groundwater storage.
Micromagnetic Tomography for Paleomagnetism and Rock‐Magnetism
Authors: de Groot Lennart V. , Fabian Karl , Béguin Annemarieke , Kosters Martha E. , Cortés‐Ortuño David , Fu Roger R. , Jansen Chloë M. L. , Harrison Richard J. , van Leeuwen Tristan , Barnhoorn Auke
Published: September 2021

Our understanding of the past behavior of the geomagnetic field arises from magnetic signals stored in geological materials, e.g., (volcanic) rocks. Bulk rock samples, however, often contain magnetic grains that differ in chemistry, size, and shape; some of them record the Earth's magnetic field well, others are unreliable. The presence of a small amount of adverse behaved magnetic grains in a sample may already obscure important information on the past state of the geomagnetic field. Recently it was shown that it is possible to determine magnetizations of individual grains in a sample by combining X‐ray computed tomography and magnetic surface scanning measurements. Here we establish this new Micromagnetic Tomography (MMT) technique and make it suitable for use with different magnetic scanning techniques, and for both synthetic and natural samples. We acquired reliable magnetic directions by selecting subsets of grains in a synthetic sample, and we obtained rock‐magnetic information of individual grains in a volcanic sample. This illustrates that MMT opens up entirely new venues of paleomagnetic and rock‐magnetic research. MMT's unique ability to determine the magnetization of individual grains in a nondestructive way allows for a systematic analysis of how geological materials record and retain information on the past state of the Earth's magnetic field. Moreover, by interpreting only the contributions of known magnetically well‐behaved grains in a sample, MMT has the potential to unlock paleomagnetic information from even the most complex, crucial, or valuable recorders that current methods are unable to recover.
Study on Dominant Parameters Determining Streamer Initiation From Hydrometeors in Thundercloud Fields
Authors: Hu Jinjin , Ma Yikai , Gao Xin , Liu Ningyu
Published: September 2021

This study reports a study trying to find the dominant factor on streamer initiation from an isolated hydrometeor in thundercloud fields at 7 km altitude corresponding to an atmosphere pressure of about 0.453 atm. Three parameters are considered including hydrometeor size, shape, and electric quantity. The simulation results indicate that a larger hydrometeor is more likely to initiate a streamer discharge at a lower ambient field for noncharged hydrometeors. The charge on hydrometeor plays a prominent role when a charged hydrometeor has a smaller size, and it is easier to initiate a streamer in this case. At 0.25 Ek, a positive streamer discharge has been presented for a charged hydrometeor with a radius of 0.5 mm. The critical field to form streamer discharge for a column shape hydrometeor without charge is much smaller than that for a spherical hydrometeor. If smaller hydrometeors are charged, the critical field for a spherical hydrometeor becomes lower than that for a column one. The electric quantity charged on hydrometeor has little effect on the critical field for both spherical and column hydrometeors, when the hydrometeor size is larger enough. The charge on hydrometeor plays a dominant role in streamer initiation when hydrometeor is smaller, but hydrometeor shape becomes more important for larger hydrometeor. Streamer discharge can be predicted by Meek number, but stable streamer cannot be ensured. Streamer branch will be met when ambient field is lower than 0.25 Ek.
N2O Is an Important Piece of the Puzzle, but Seeing the Whole Picture Strengthens Denitrification Research
Authors: Emmett B. D.
Published: September 2021

For decades, denitrification research has been limited by the challenge of measuring fluxes of N2 against a background of high atmospheric concentrations. The methods developed to overcome this challenge all have strengths and weaknesses. Weitzman et al. (2021, https://doi.org/10.1029/2020JG006234) demonstrate the potential of one technique, the Nitrogen‐Free Air Recirculation Method, to measure denitrification end‐products in relatively undisturbed soil cores. This work reinforces the importance of N2 as the primary end‐product of denitrification, accounting for over 86% of measured fluxes in all cores sampled, and reveals unforeseen hotspots of denitrification at depth in soil. These findings are consistent with a similar effort to improve estimates of N2O: N2O + N2 yield at the field scale that predicts N2 fluxes two to three times higher than predicted using previous estimates. By providing a more complete picture of N2O and N2 production in terrestrial systems, these efforts can strengthen denitrification research and support essential refinement of ecosystem models. The identification of unforeseen denitrification hotspots highlights the continued surprises of soil nitrogen cycle and should inspire mechanistic research into the biophysical drivers and communities that mediate denitrification hotspots.
A monolithic InP/SOI platform for integrated photonics
Authors: Yan Zhao , Han Yu , Lin Liying , Xue Ying , Ma Chao , Ng Wai Kit , Wong Kam Sing , Lau Kei May
Published: September 2021

The deployment of photonic integrated circuits (PICs) necessitates an integration platform that is scalable, high-throughput, cost-effective, and power-efficient. Here we present a monolithic InP on SOI platform to synergize the advantages of two mainstream photonic integration platforms: Si photonics and InP photonics. This monolithic InP/SOI platform is realized through the selective growth of both InP sub-micron wires and large dimension InP membranes on industry-standard (001)-oriented silicon-on-insulator (SOI) wafers. The epitaxial InP is in-plane, dislocation-free, site-controlled, intimately positioned with the Si device layer, and placed right on top of the buried oxide layer to form “InP-on-insulator”. These attributes allow for the realization of various photonic functionalities using the epitaxial InP, with efficient light interfacing between the III–V devices and the Si-based waveguides. We exemplify the potential of this InP/SOI platform for integrated photonics through the demonstration of lasers with different cavity designs including subwavelength wires, square cavities, and micro-disks. Our results here mark a critical step forward towards fully-integrated Si-based PICs.