bluuebunny/crossref_metadata_2025 huggingface dataset:
Control Evaluation of Antagonistic Series Elastic Actuation for a Robotic Endoscope Joint
Authors: Fasel Lorin , Gerig Nicolas , Cattin Philippe C. , Rauter Georg
Published: March 2022

Haptic feedback is typically missing during telemanipulation of surgical robots in minimally invasive surgeries, i.e., surgeons cannot feel the interaction forces between the instruments and tissues. Instead, surgeons have to solely rely on visual feedback, which increases complexity of guiding the instruments and poses the safety threat of unperceivable contacts outside the field of view. We propose a novel series elastic actuation design for articulated robotic endoscopes to overcome these limitations and evaluate an according device with one joint. Similar to the actuation of human fingers, the joint is driven by antagonistic tendons. Springs are integrated in the transmission between the tendons and the motors outside of the endoscope shaft. We estimated the joint angle and thereby the endoscope shape, measured spring deflection, estimated tendon forces from that deflection, and implemented force control for the endoscope joint. Zero torque control and impedance control were evaluated under application of both a continuous force and an impact force to the endoscope tip. The springs reduced impact forces at the tip of the endoscope through their inherent compliance. At the same time, feeding back the estimated force resulted in a stable tendon force control and a tunable endoscope joint control: Zero torque control effectively reduced the external forces, while the endoscope joint showed the expected stiffness in impedance control. These results show that antagonistic series elastic actuation is a promising concept for endoscope joint actuation and that it can lead towards safer robot–tissue interactions in surgical robotics.
Intracavernosal OnabotulinumtoxinA Exerts a Synergistic Pro-Erectile Effect When Combined with Sildenafil in Spontaneously Hypertensive Rats
Authors: Giuliano Francois , Joussain Charles , Denys Pierre , Laurin Miguel , Behr-Roussel Delphine , Assaly Rana
Published: March 2022

Background

Botulinum toxin A (BTX-A) has a variety of uses in medicine. Some evidence suggests that intracavernosal (ic) BTX-A injection administered in addition to phosphodiesterase type 5 inhibitors (PDE5-Is) could effectively treat erectile dysfunction (ED) in insufficient responders to PDE5-Is.

Aim

To provide experimental pharmacological evidence for the use of onabotulinumtoxinA ic alone or in combination with PDE5-Is for difficult-to-treat ED. We thus compared the effects of BTX-A ic alone and BTX-A ic combined with PDE5-I iv, and a placebo treatment ic or iv.

Methods

Erectile function was evaluated following cavernous nerve electrical stimulation (6 V, 1-millisecond pulse, 45-second duration) at different frequencies (0, 2, 3, 4, 5, 7.5, and 10 Hz) in 4 groups (n = 8 / group) of anesthetized, spontaneously hypertensive rats, a robust animal model of ED of vascular origin. Rats were treated by onabotulinumtoxinA 10U or saline ic 1 week prior to erectile function testing and sildenafil (0.3 mg/kg) or saline iv 4 minutes prior to testing. Frequency-response curves were compared with a 2 way ANOVA.

Outcomes

Both onabotulinumtoxinA ic, and sildenafil iv significantly improved erectile responses in spontaneously hypertensive rats, however the effect was greatly amplified when the treatments were combined.

Results

Intracavernosal pressure and/or mean arterial pressure ratios were significantly increased by sildenafil and onabotulinumtoxinA ic versus the control condition. OnabotulinumtoxinA 10U ic combined with sildenafil iv significantly potentiated erectile responses. Area under the curve and/or mean arterial pressure ratio increased by 19% with sildenafil iv, by 15% with onabotulinumtoxinA ic and by 58% with the combined treatment following cavernous nerve electrical stimulation at 6V, 1 ms, 10 Hz: these stimulation parameters elicited the maximal erectile response.

Clinical Translation

These data provide a pharmacological rationale for the combined administration of onabotulinumtoxinA ic and sildenafil iv since the effects of both treatments were potentiated when their administration was combined.

Strengths & Limitations

First evidence of a synergistic pro-erectile effect of BTX-A combined with PDE5-I, however the mechanism behind the pro-erectile effect of BTX-A ic remains hypothetical.

Conclusions

These results support further studies into the mechanisms behind the pro-erectile effect of BTX-A ic, as well as multicenter randomized control trials to evaluate the safety and efficacy of BTX-A ic combined with sildenafil for difficult-to-treat ED.
The chameleonic nature of freedom: notes on the concept offahafahanain the Highlands of Madagascar
Authors: Gardini Marco
Published: March 2022

This article explores the conceptual and practical meanings offahafahana(‘freedom’ in Malagasy) in the Highlands of Madagascar, a context where the legacies of past forms of slavery have left deep marks both in local memories and in social and economic hierarchies. In particular, it focuses on the ways in which specific notions of freedom have been elaborated against the background of the local history of slavery and emancipation; how these concepts have been charged with different meanings in different periods of Malagasy history, becoming an arena for the elaboration of different political agendas; and how people of different status, class, gender and age reframe the concept of freedom in their everyday lives. Local notions of freedom emerge as part of the local political commentaries through which power positions are accepted, renegotiated or contested, and they intersect deeply with local notions of honour and respectability. The idea that freedom is somehow related to issues of genealogical purity and to the ability to maintain and improve the wealth and dignity of the family continues to characterize local understandings and representations of this notion, signalling that the legacies of what it meant to be ‘free’ when slavery was still a legal institution still inform and shape current power structures and local social commentaries.
Deficit or Austerity Bias? The Changing Nature of Canadians’ Opinion of Fiscal Policies
Authors: Jacques Olivier , Bélanger Éric
Published: March 2022

Public choice theory suggests that citizens have a deficit bias: they approve governments for running large deficits that increase spending or reduce taxes. In contrast, others contend that citizens reward governments for balanced budgets. We contribute to this debate by modelling a popularity function for the Canadian federal government and show that the impact of fiscal policies on the executive's popularity changes over time. Until the early 1990s, Canadians preferred budget deficits. As deficits became unsustainable during the economic crisis of the early 1990s, the government shifted its fiscal policy paradigm, as balancing the budget became its primary fiscal objective and citizens were actively concerned about the deficits. Since 1993, citizens’ deficit bias morphed into an austerity bias: executive approval increases when deficits are reduced. These findings contribute to comparative political economy research by assessing how policy regimes and public preferences reinforce each other.
The Place of Constitutional Conventions in the Constitutional Architecture, and in the Courts
Authors: Macfarlane Emmett
Published: March 2022

The Supreme Court's recent invocation of the “constitutional architecture” in theSenate Reform Referencehas led a number of scholars to question the status of constitutional conventions in the legal, as opposed to political, constitution. Has the Court, without expressly saying so, transformed at least some conventions into constitutional law? This would be a serious rupture, not only from existing precedent on the justiciability of conventions but also from the traditional understanding of conventions as binding political rules. In light of this recent scholarly debate, an exploration of the profound consequences of entrenching conventions in the legal constitution is warranted, as it implicates the meaning of constitutional conventions, their creation, their relation to law, and their enforcement. Judicial entrenchment of conventions would be a dangerous violation of the separation of powers and would have negative consequences for the functioning of Canada's system of government and for the future of constitutional change.
Are all antidepressants the same? The consumer has a point
Authors: Camino Sebastian , Strejilevich Sergio A. , Godoy Antonella , Smith Jose , Szmulewicz Alejandro
Published: March 2022

Background

Although a large variety of antidepressants agents (AD) with different mechanisms of action are available, no significant differences in efficacy and safety have been shown. However, there have been few attempts to incorporate data on subjective experiences under different AD.

Method

We conducted a qualitative and quantitative analysis of the posts from the websitewww.askapatient.comfrom different AD. We reviewed a random sample of 1000 posts.

Result

After applying the inclusion and exclusion criteria, we included a final sample of 450 posts, 50 on each of the most used AD: sertraline, citalopram, paroxetine, escitalopram, fluoxetine, venlafaxine, duloxetine, mirtazapine, and bupropion. Bupropion, citalopram, and venlafaxine had the higher overall satisfaction ratings. Sertraline, paroxetine, and fluoxetine had high reports of emotional blunting, while bupropion very few. Overall satisfaction with AD treatment was inversely associated with the presence of the following side-effects: suicidality, irritability, emotional blunting, cognitive disturbances, and withdrawal symptoms. After adjusting for confounders, only emotional blunting was shown to be more frequently reported by users of serotonergic agents, as compared to non-serotoninergic agents.

Conclusion

This research points out that the subjective experience of patients under treatment should be taken into consideration when selecting an AD as differences between agents were evident. In contrast to the more frequent treatment decisions, users might prefer receiving a non-serotoninergic agent over a serotonergic one due to their lower propensity to produce emotional blunting.
Calcium Imaging and Electrophysiology of hippocampal Activity under Anesthesia and natural Sleep in Mice
Authors: Formozov Andrey , Chini Mattia , Dieter Alexander , Yang Wei , Pöpplau Jastyn A. , Hanganu-Opatz Ileana L. , Wiegert J. Simon
Published: March 2022

The acute effects of anesthesia and their underlying mechanisms are still not fully understood. Thus, comprehensive analysis and efficient generalization require their description in various brain regions. Here we describe a large-scale, annotated collection of 2-photon calcium imaging data and multi-electrode, extracellular electrophysiological recordings in CA1 of the murine hippocampus under three distinct anesthetics (Isoflurane, Ketamine/Xylazine and Medetomidine/Midazolam/Fentanyl), during natural sleep, and wakefulness. We cover several aspects of data quality standardization and provide a set of tools for autonomous validation, along with analysis workflows for reuse and data exploration. The datasets described here capture various aspects of neural activity in hundreds of pyramidal cells at single cell resolution. In addition to relevance for basic biological research, the dataset may find utility in computational neuroscience as a benchmark for models of anesthesia and sleep.
Clinical outcomes and revision rates following four-level anterior cervical discectomy and fusion
Authors: Charalampidis Anastasios , Hejrati Nader , Ramakonar Hari , Kalsi Pratipal S. , Massicotte Eric M. , Fehlings Michael G.
Published: March 2022

Studies on outcomes after four-level anterior cervical discectomy and fusion (ACDF) are limited in the literature. The purpose of this study was to report on clinical outcomes and revision rates following four-level ACDF. Patients operated with four-level ACDF were identified in a prospectively accrued single institution database. Outcome scores included the Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for neck and arm pain. Reoperation rates were determined. Any complications were identified from a review of the medical records. Twenty-eight patients with a minimum of 12 months follow up were included in the analysis. The mean age at surgery was 58.5 years. The median radiographic follow up time was 23 (IQR = 16–31.25) months. Cervical lordosis was significantly improved postoperatively (− 1 to − 13, p < 0.001). At the median 24 (IQR = 17.75–39.50) months clinical follow up time, there was a significant improvement in the NDI (38 to 28, p = 0.046) and VAS for neck pain scores (5.1 to 3, p = 0.012). The most common perioperative complication was transient dysphagia (32%) followed by hoarseness (14%). Four (14%) patients required revision surgery at a median 11.5 (IQR = 2–51) months postoperatively. The results of this study indicate that patients who undergo four-level ACDF have a significant improvement in clinical outcomes at median 24 months follow up. Stand-alone four-level ACDF is a valid option for the management of complex cervical degenerative conditions.
Conduction and Inertia Correction for Transient Thermocouple Measurements. Part I: Analytical and Numerical Modelling
Authors: Seibold Florian , Schwab Andreas , Dubois Victor , Poser Rico , Weigand Bernhard , von Wolfersdorf Jens
Published: March 2022

Two-wire thermocouples are often used for temperature measurements. Under transient conditions, measurement errors can occur due to capacitive inertia and heat conduction along the stem of the thermocouples. The present study presents a correction of these thermocouple measurement errors caused by transient inertia and conductive effects using a simplified analytical approach and its numerical solution. Based on an energy balance the mathematical modelling is derived and analytically solved for specific boundary conditions. Further, numerical solutions have been implemented with different model complexities. Thereby the models show the significance of the necessary correction as well as the good agreement with theoretical considerations. A corresponding experimental validation is given in Part II.
On Directional Sensitivity of Thermo-Anemometer Split-Fiber Probes
Authors: Lepicovsky Jan
Published: March 2022

Hot-wire thermo-anemometer probes are extremely fragile and they are used mostly in clean flows with neither debris nor small particles to prevent sensor destruction. Consequently, application of hot-wire probes is limited mostly to clean laboratory environments, their employment in semi-industrial research is extremely rare, and not always successful. Film probes with deposited thin metallic sensors on cylindrical fibers are more rugged and can be successfully employed for research tasks in semi-industrial environment. Surprisingly the potentials of these probes are not yet fully utilized. Detailed investigation of direction characteristics of a split-fiber probe was carried out during the course of this work. Several interesting outcomes resulted from this study. First, it has been shown that the split-fiber probe direction sensitivity rises with the increasing velocity contrary to the decrease of the velocity sensitivity, which is a common hindrance to application of single-sensor thermo-probes to high-speed and transonic flows. Second, the analysis of the acquired data revealed a sudden shift in the effective zero angle offset. It can be speculated that such a shift can related to the transition of the laminar vortex street into the turbulent one. However, the observed shift occurred at Reynolds number values between 900 and 1000, which is markedly higher than the usually reported transitional Reynolds number range between 150 and 300. Finally, the resilience of split-fiber probes to impairment by in-flow debris has been demonstrated proving the probe ability for effective use of these probes in semi-industrial or even industrial research tasks.
Using a pupal exuvia to designate the undamaged neotype of a species belonging to a complex of sibling species – the case of Aedes coluzzii (Diptera, Culicidae)
Authors: Berger Audric , Le Goff Gilbert , Boussès Philippe , Rahola Nil , Ferré Jean-Baptiste , Ayala Diego , Robert Vincent
Published: March 2022

The mosquito species Aedes (Ochlerotatus) coluzzii Rioux, Guilvard & Pasteur, 1998 was distinguished from its sibling species Aedes detritus (Haliday, 1833) using an isoenzymatic method that required the destruction of the entire specimen, therefore no holotype was designated by the species authors. We aimed to designate a neotype for Ae. coluzzii from specimens collected from the type-locality and individually reared up to adult stage. Genomic DNA was extracted from pupal exuvia and ITS2 was sequenced, enabling verification of the identity of each specimen as Ae. coluzzii or Ae. detritus. Among the series of Ae. coluzzii, a male was designated as neotype and deposited in a collection. To our knowledge, this is the first time the type of a mosquito species is deposited thanks to its molecular identification from its pupal exuvia. The set of identified specimens allowed additional phylogenetic and morphologic studies.
Wireless, minimized, stretchable, and breathable electrocardiogram sensor system
Authors: Xuan Yan , Hara Hyuga , Honda Satoko , Li Yanpeng , Fujita Yusuke , Arie Takayuki , Akita Seiji , Takei Kuniharu
Published: March 2022

Home-use, wearable healthcare devices may enable patients to collect various types of medical data during daily activities. Electrocardiographic data are vitally important. To be practical, monitoring devices must be wearable, comfortable, and stable, even during exercise. This study develops a breathable, stretchable sensor sheet by employing a kirigami structure, and we examine the size dependence of electrocardiographic sensors. Because the kirigami film has many holes, sweat readily passes through the sensor from the skin to the environment. For comfort, in addition to breathability, electrocardiographic sensor size is minimized. The limitation of the size is studied in relation to the signal-to-noise ratio of electrocardiographic signals, even under exercise. We found that the optimal size of the sensor is ∼200 mm2 and the distance between electrodes is 1.5 cm. Finally, long-term wireless electrocardiographic monitoring is demonstrated using data transmission to a smart phone app during different activities.
Novel interaction between an octopus and an introduced macroalgae
Authors: Storero Lorena Pía , Pereyra Patricio Javier
Published: March 2022

Numerous macroalgae facilitate other species, modifying the diversity patterns, reducing the environmental stress, or providing non-trophic resources. In the sandy–pebbly bottoms of San Antonio Bay (north Patagonia, Argentina), where shelters are an important but limiting resource for the small Patagonian octopus (Octopus tehuelchus), the recently introduced macroalgae Undaria pinnatifida has shown a rapid increase in abundance. Herein, we documented the use of U. pinnatifida as shelter for octopuses and describe the size and maturity condition of individuals using the macroalgae. Our results suggest that U. pinnatifida facilitates octopuses by providing shelter in an environment where these are scarce and there is competition for high-quality shelters. The presence of small octopuses and brooding females under U. pinnatifida suggest that the structure of the macroalgae constitute an adequate shelter for brooding and may facilitate a portion of the population that usually lose the competition for traditional shelters. Indeed, the holdfast of U. pinnatifida, full of potential food sources, may provide a larger positive effect on octopuses. The effects of U. pinnatifida in north Patagonia should be tested on the different components of the community since there seem to be no similar native macroalgae providing structural complexity in these sandy–pebbly bottom ecosystems.
Emotion terms in Malay
Authors: Chung Siaw-Fong
Published: March 2022

This study examined 25 emotion terms in Malaysian Malay and used corpus data to investigate whether these emotion terms appeared with the [meN-], [meN‑ -i], [meN‑ -kan], and [‑kan]-only forms. The emotion terms were patterned in four different ways. Category One included local emotion verbs that conformed to the pattern [Affector-Affectee]. In this category, the verbs were dominated by the [meN‑ -i] form, with a small number including the suffix [‑kan]-only. A verb in the [meN‑ -kan] form was either a Category Two [CausermeN‑ -kanCausee] pattern or a Category Four [ExperiencermeN‑ -kanEvent] pattern, among which Category Two had a higher number of instances. Category Three included two possible patterns – [ExperiencermeN‑ -iStimulus] and [ExperiencermeN‑ (Stimulus absent)]. We found that the emotion terms with the [meN-]-only form were largely “narrating” the emotions of the speaker or situation, which provided the background, while the emotion terms with the [‑kan]-only form were largely “proposing” the emotion of the speaker or the subject being referred to (cf.Hopper 1983;Bambang Kaswanti Purwo 1988). We were able to discern not only emotion terms in Malay but also their different uses in [meN-], [meN‑ -i], [meN‑ -kan], and [‑kan]-only forms.
Temporal partitions in the grammaticalization of imperfective aspect markers
Authors: Dong Hongyuan
Published: March 2022

This article proposes a new account for the typologically uncommon grammaticalization path from an adjective meaning ‘tight’ to a progressive aspect marker in Cantonese. I take a formal approach to explain the cognitive foundations in such a grammaticalization path by using formal semantic theories and tools. There are two components in the meaning of the progressive aspect, i.e. temporal inclusion and dynamism. The meaning ‘tight’ is transferred from the spatial domain to describe the close succession of events, which gives rise to the dynamic meaning component. Furthermore, this eventual dynamism is mapped to the temporal domain, which corresponds to the regular partition of the time interval with an infinitesimal measure in the semantics proposed by Deo (2009). My analysis is extended to explain the Cantonese habitual marker with an original meaning ‘open’, and to the use of morphological reduplication to express the imperfective aspect in languages from the Austronesian and Pama-Nyungan families. The theoretical contribution of this article is that the grammaticalization paths of certain aspect markers share a common cognitive foundation in terms of space, events, and time, but they may take different trajectories of evolution that target different parts of a functional morpheme with complex meanings.
From ‘two’ to a comitative-instrumental case marker
Authors: Zhou Chenlei
Published: March 2022

This paper examines the comitative and instrumental case markers in the Chinese dialects and Altaic languages spoken in the Gansu-Qinghai Linguistic Area (GQLA) and finds a noteworthy phenomenon: one of the frequently used comitative-instrumental markers originated from the numeral ‘two’, a rare source for comitatives. The numeral ‘two’ is grammaticalized under the process of {‘two’ (appositive) > coordinator > comitative > instrumental}. This paper argues that the marker ‘two’ in Chinese dialects did not have an Altaic origin and was then borrowed for Chinese, asDwyer (1992)suggested. The fact that the comitative-instrumental markers in both Altaic (especially Mongolic) languages and Chinese dialects come from the numeral ‘two’ with comitative-instrumental syncretism reflects a regional innovation in GQLA.
A lab‐based comparison of differential ratings of perceived exertion between a run and jump protocol involving low or high impacts on the lower extremities
Authors: Houtmeyers Kobe C. , Brink Michel S. , Helsen Werner F. , Haelewijn Nicolas , Hagen Michiel , Jaspers Arne , Vanrenterghem Jos
Published: March 2022

The rating of perceived exertion method (RPE) allows to describe training intensity in a single value. To better understand the underlying components, the separate rating of perceived breathlessness (RPE‐B) and leg‐muscle exertion (RPE‐L) has been proposed. Here we hypothesised that the separation between the two components may (partly) be determined by the impacts on the lower extremities. In this study, we aimed to experimentally evaluate the differential effect of high versus low impact running and jumping on RPE‐B and RPE‐L in team sport activities by manipulating the movement strategy (heel strike and passive landing pattern versus forefoot strike and active landing pattern). Eighteen recreational team sport players participated in two submaximal tests consisting of a sequence of running and jumping bouts, whilst ground reaction forces (GRF) were collected. RPE‐B and RPE‐L data were collected after each bout using the CR100 scale. Paired‐samples t‐tests were used to analyse between‐session differences in these variables. GRF analysis showed that absorption mechanics differed considerably between the two sessions. RPE‐L was on average 6.50 AU higher in the low impact session (p = 0.006). However, RPE‐B was also increased by 4.96 AU with low impact (p = 0.009). We conclude that the extent to which the lower extremities are being exposed to high or low impacts does not explain a possible separation between the two RPE types.

Highlights

The separate rating of the different underlying components of RPE (e.g. variables related to the cardiorespiratory and the muscular system) may provide more insight in the relationship between training load and training outcomes, which likely differs between these components.

The findings of this study do not support the idea that the separation in rating between perceived breathlessness (RPE‐B, cardiorespiratory) and leg‐muscle exertion (RPE‐L, muscular) is also rooted in the extent to which musculoskeletal structures in the lower extremities are being exposed to high or low impacts.
Bounding uncertainties around the conceptual representation of species in radiological assessment in the context of routine atmospheric release
Authors: Charrasse Benoit , Mora Juan C , Anderson Tracey , Bonchuk Yuri , Telleria Diego
Published: March 2022

Wildlife protection has become of regulatory interest since the International Commission on Radiological Protection (ICRP) developed an approach to assess the level of radiological protection specifically for animals and plants. For the purpose of demonstrating compliance with regulation to protect the environment against routine authorised discharges from nuclear facilities, the wide variety of biota inhabiting an ecosystem needs to be condensed to a limited set of representative organisms, as proposed by the ICRP with a set of ‘reference animals and plants’ which can be considered representative of many other species. It is now recommended in the International Atomic Energy Agency Safety Standards, and internationally accepted, that the use of such a limited number of organisms to represent a pool of species is adequate for radiation protection purposes, particularly in planned exposure situations. Adding site-specific species to that set of surrogate species can respond to various interests, such as ensuring a site-specific context to the assessment that addresses stakeholder interests and can aid in stakeholder consultation and risk communication. Moreover, there is a need to question whether the use of the set of surrogate organisms is conservative enough to cover a wider range of biodiversity. Previous studies partially answered this question and this paper adds a range of test cases. A selection of hypothetical representations of possible site-specific species are assessed on the basis of possible variations in size (mass) and occupancy habits. Dose rates are evaluated to determine the greatest difference between hypothetical organisms and those for reference organisms (ROs), considering radionuclides (RNs) potentially discharged in atmospheric routine release from different nuclear facilities. Differences observed in the results between hypothetical organisms and ROs were less than one order of magnitude in all cases, the difference being dependent on the RNs considered. These findings do not preclude the inclusion of site-specific species in environmental radiological assessments if it is considered necessary, but they provide reassurance that using ROs for radiological impact assessments in the case of routine atmospheric discharges is sufficient.
A new approach for simulating D-T fusion interaction using the Geant4 toolkit
Authors: Mohtashami S. , Moshkbar-Bakhshayesh K.
Published: March 2022

In this study, the Geant4 toolkit is utilized to present a
new approach for simulation of the D-T interaction. The neutron
production cross-section and the energy/angle distribution of
neutrons produced as the D-T data libraries are incorporated in the
Geant4, and their performance is evaluated. The spectra shape of the
produced neutrons of the D-T interaction simulated by the Geant4
show good agreement compared to the results of the comparative codes
(i.e. MCUNED, ENEA-JSI, and DDT). However, some differences are
observed, especially, in angular range of 90–95 degrees. The reason
for these differences as well as the results of the proposed
approach in comparison with the results of the benchmark experiments
as the next study are under consideration.
Gelatin-glucosamine hydrochloride/crosslinked-cyclodextrin metal-organic frameworks@IBU composite hydrogel long-term sustained drug delivery system for osteoarthritis treatment
Authors: Yang Hui , Hu Yinchun , Kang Min , Ding Huixiu , Gong Yue , Yin Xiangfei , Sun Ruize , Qin Yuhong , Wei Yan , Huang Di
Published: March 2022

Osteoarthritis (OA) is a disease of articular cartilage degradation and inflammation of the joint capsule. Combining anti-inflammatory therapy with nutritional supplement is an effective means for the treatment of OA. In this study, we prepared gelatin (Gel)-glucosamine hydrochloride (GH) mixed crosslinked-cyclodextrin metal-organic framework (G-GH/CL-CD-MOF) composite hydrogel. Polyethylene glycol diglycidyl ether was the crosslinking agent of GH and Gel to solve the problem of poor mechanical properties and water solubility at 37 °C. CL-CD-MOF was fabricated through a simple one-step chemical reaction to crosslink the hydrophilic hydroxyl groups in CD-MOF with diphenyl carbonate. Electron microscopy and x-ray diffraction analysis of CL-CD-MOF showed perfect porous morphology with a chaotic internal structure. CL-CD-MOF@IBU was prepared by immersing CL-CD-MOF in high-concentration ibuprofen (IBU) solution. CL-CD-MOF@IBU was uniformly dispersed in Gel and GH mixed solution to prepare G-GH/CL-CD-MOF@IBU composite hydrogel long-term sustained drug delivery system. The compression curve of G-GH/CL-CD-MOF composite hydrogel showed a non-linear elastic behavior. The cyclic loading–unloading compression showed that the shape of the G-GH/CL-CD-MOF composite hydrogel can be kept intact under 50% strain. On the day 14, the G-GH/CL-CD-MOF@IBU composite hydrogel was degraded by 87.1%, 61% of IBU was released. G-GH/CL-CD-MOF@IBU exhibited good biocompatibility during co-culture with MC3T3-E1 cells. Briefly, the certain mechanical properties, sustained drug release behavior, and good biocompatibility of G-GH/CL-CD-MOF@IBU composite hydrogel showed that it has potential application in OA treatment of long-term sustained nutritional supplement and anti-inflammatory synchronously.
Strontium-loaded titanium implant with rough surface modulates osseointegration by changing sfrp4 in canonical and noncanonical Wnt signaling pathways
Authors: Wang Xiaoyi , Xin He , Ning Xiaona , Zhang Yubohan , Liu Fuwei , Zhang Zhouyang , Jia Xuelian , Guo Weiwei , Hong Yonglong , Sui Wen
Published: March 2022

A rough morphology and strontium (Sr) can activate the Wnt pathway to regulate bone mesenchymal stem cells (rBMSCs) osteogenic differentiation, but the mechanism remains unclear. We constructed smooth Ti (ST) surfaces, rough Ti (RT) surfaces subjected to hydrofluoric acid etching, strontium-loaded smooth Ti (ST-Sr) surfaces subjected to magnetron sputtering, and rough strontium-loaded Ti (RT-Sr) surfaces. We systematically studied the in vitro osteogenic differentiation of rBMSCs on these four surfaces by alkaline phosphatase measurement, Alizarin Red staining and polymerase chain reaction (PCR). We also investigated whether crosstalk of the canonical and noncanonical Wnt signaling pathways regulated by sfrp4, which is an inhibitor of canonical and noncanonical Wnt, is the underlying mechanism via PCR on rBMSCs in different stages of osteogenic differentiation. We confirmed the effect of sfrp4 through an in vivo sfrp4-siRNA test. The in vitro osteogenic differentiation of rBMSCs decreased in the order RT-Sr, RT, ST-Sr, and ST. Regarding the mechanism, rough morphology and Sr both enhanced the canonical Wnt pathway to promote osseointegration. Additionally, rough morphology can inhibit sfrp4 to activate the noncanonical Wnt pathway, and then, the activated noncanonical Wnt pathway can suppress the canonical Wnt pathway at the early stage of osteogenic differentiation. Sr continuously enhanced sfrp4 to inhibit the canonical Wnt pathway instead of activating the noncanonical Wnt pathway. Interestingly, the effect of rough morphology on sfrp4 changed from inhibition to enhancement, and the enhancing effect of Sr on sfrp4 was gradually attenuated. The results of the in vivo sfrp4-siRNA test showed that osseointegration decreased in the order RT-Sr, RT-Sr-siRNA, and ST. Our results suggest that the lack of sfrp4 could suppress osseointegration, indicating that sfrp4 acts as a crucial regulatory molecule for the canonical and noncanonical Wnt pathways during the response of rBMSCs to rough morphology and Sr.
Cumulative disturbance converts regional forests into a substantial carbon source
Authors: Giles-Hansen Krysta , Wei Xiaohua
Published: March 2022

British Columbia’s interior forests (∼400 000 km2) have experienced severe cumulative disturbance from harvesting, wildfires, and mountain pine beetle (MPB). Estimating their impacts on carbon dynamics is critical for effective forest management and climate-change mitigation strategies. This study quantifies the magnitude of historical cumulative forest disturbances and models the effect on regional carbon stocks and emissions using the Carbon Budget Model of the Canadian Forest Service from 1980 to 2018. The study region has been a sustained carbon source since 2003, with an estimated net biome production of −18.6 ± 4.6 gC m−2 yr−1 from 2003 to 2016, dropping to −90.4 ± 8.6 gC m−2 yr−1 in 2017 and 2018 due to large-scale wildfires. MPB affected areas emitted an estimated 268 ± 28 Mt C from 2000 to 2018. Harvesting transferred an estimated 153 ± 14 Mt C to forest products and these areas also emitted 343 ± 27 Mt C in 2000–2018. Areas disturbed by wildfire from 2000 to 2018 generated an estimated 100 ± 8 Mt C of emissions, 73% of which were from 2017 and 2018. Of the area burned between 2014 and 2018, 38% had been previously affected by MPB, highlighting landscape-level interactions of cumulative forest disturbance. Approximately half of decomposition carbon emissions from disturbances in 2000–2018 were calculated as incremental to the decomposition that would have otherwise occurred without MPB disturbance. The average net primary production was reduced by 10% to 335 ± 31 gC m−2 yr−1 from 2000 to 2018. We conclude that cumulative forest disturbance has driven the region’s forests to become a sustained carbon source over the past two decades. While MPB and harvesting were dominant and consistent drivers, recent severe wildfires have prolonged and strengthened the carbon source. Increased disturbances, driven in part by climate change, may limit the ability of regional forests to meet national carbon emission reduction targets.
Jamming and percolation in the random sequential adsorption of a binary mixture on the square lattice
Authors: Kundu Sumanta , Prates Henrique C , Araújo Nuno A M
Published: March 2022

We study the competitive irreversible adsorption of a binary mixture of monomers and square-shaped particles of linear size R on the square lattice. With the random sequential adsorption model, we investigate how the jamming coverage and percolation properties depend on the size ratio R and relative flux F. We find that the onset of percolation of monomers is always lower for the binary mixture than in the case with only monomers (R = 1). Moreover, for values F below a critical value, the higher is the flux or size of the largest species, the lower is the value of the percolation threshold for monomers.
Multiple-SLE
κ
connectivity weights for rectangles, hexagons, and octagons
Authors: Flores Steven M , Simmons Jacob J H , Kleban Peter
Published: March 2022

In previous work, two of the authors determined, completely and rigorously, a solution space

S

N

for a homogeneous system of 2N + 3 linear partial differential equations (PDEs) in 2N variables that arises in conformal field theory (CFT) and multiple Schramm–Löwner evolution (SLE
κ
). The system comprises 2N null-state equations and three conformal ward identities that govern CFT correlation functions of 2N one-leg boundary operators or SLE
κ
partition functions. M Bauer et al conjectured a formula, expressed in terms of ‘pure SLE
κ
partition functions,’ for the probability that the growing curves of a multiple-SLE
κ
process join in a particular connectivity. In a previous article, we rigorously define certain elements of

S

N

, which we call ‘connectivity weights,’ argue that they are in fact pure SLE
κ
partition functions, and show how to find explicit formulas for them in terms of Coulomb gas contour integrals. Our formal definition of the connectivity weights immediately leads to a method for finding explicit expressions for them. However, this method gives very complicated formulas where simpler versions may be available, and it is not applicable for certain values of κ ∈ (0, 8) corresponding to well-known critical lattice models in statistical mechanics. In this article, we determine expressions for all connectivity weights in

S

N

for N ∈ {1, 2, 3, 4} (those with N ∈ {3, 4} are new) and for so-called ‘rainbow connectivity weights’ in

S

N

for all

N
∈

Z

+

+
1

. We verify these formulas by explicitly showing that they satisfy the formal definition of a connectivity weight. In appendix B, we investigate logarithmic singularities of some of these expressions, appearing for certain values of κ predicted by logarithmic CFT.
Assessing void in Grade-A office buildings in Lagos metropolis
Authors: Iroham C.O. , Salubi D.O. , Okagbue H.I. , Oletubo A.A.
Published: March 2022

The evidence of void in the most categorized office buildings, Grade-A Office Buildings, spurred this research. It was conceived that such office buildings that are built with every form of specifications should be the choice of occupants and as such should not experience any void. This study thereby aimed at discovering factors that lead to such void, proportion of void experienced and the average rent loss and period of void as a result of the lull in the property market for such class of property. The research being a survey entailed the distribution of questionnaires to the property managers of the twelve identified Grade-A Office Buildings in the study area. Data gotten were analysed using descriptive and inferential statistics through the use of Statistical Package for the Social Sciences (SPSS) Version 25. Subsequent discussions were made in line with proffered suggestion with a view to eradicating or at least reducing the void so as to enhance the investment outcome.
Evaluation of background radiation of Maryland School complex, Lagos, Nigeria
Authors: Morakinyo R.O. , Usikalu M.R. , Orosun M.M.
Published: March 2022

The background radiation of Maryland School Complex was taken using RS-125 hand-held gamma spectrometer. The average concentration of the measured radionuclides were 19.16, 46.14, 165.00 Bq/kg for 238U, 232Thand 40K, respectively. The average value of measured dose rate and the estimated dose rate were 44.93 and 43.55Bq/kg. The mean values of the estimated radiological parameter were 53.45, 213.78μSv/y for indoor and outdoor annual effective dose. The excess lifetime cancer risk averaged 0.17, the hazard indices were 0.26 and 0.32 for external and internal respectively. The annual gonadal dose and radium equivalent were 303.90 μSv/y and 97.85 Bq/kg, while the gamma representative index was 0.69. The mean concentration of radionuclides measured and the estimated radiological parameter were within the recommended values. This therefore follows that the risk of exposure to ionizing radiation for both the staff and the students of the community is within acceptable limits.
Analysis of Solar Ultraviolet radiation Index over Nigeria, West Africa
Authors: Arijaje T.E. , Omotosho T.V. , Akinwumi S.A. , Ometan O.O. , Fashade O.O.
Published: March 2022

UV solar radiation are essential for living here on earth, however, at extreme levels, it becomes harmful to all organism with negative effects on humans due to UV-A and UV-B penetrating the earth’s surface. UV radiation index was analyzed over Nigeria, using ten years daily data extracted from the archive of the Ozone Monitoring Instrument (OMI) on-board the EOS Aura spacecraft at a coordinate of 9.08° N, 9. 67° E. The result showed that solar UV radiation is at its peak at local noon time from January 2010 to December 2019. The peak value was observed in the month of November, December, January, February, and March. Hence, the study revealed that the ultraviolet index over Nigeria's varies from high to extreme (i.e., from the Southern to the Northern regions). In conclusion, our findings will create an awareness on those regions with extreme UV radiation and measures such as using sun glasses, umbrellas and putting on protective clothes against the harmful effect of UV radiation.
Distinguishing bacteria from minerals in a layered sample using time-resolved Raman spectroscopy and global analysis
Authors: Mooij Bram J A , van Stokkum Ivo H M , Davies G R , Ariese Freek
Published: March 2022

Mars is one of the prime candidates in the search for extraterrestrial life. At the most comparable terrestrial Martian analogue sites, life often occurs in endolithic form; i.e. hiding below the surface. To detect biomarkers of endolithic life, the two most promising options are drilling or measuring through the surface, the latter being less invasive and preferable. Raman spectroscopy is an established chemical identification method, and advanced Raman modes have been developed for sub-surface analysis. Time-resolved Raman spectroscopy (TRRS), based on picosecond pulsed excitation and a gated intensified charge-coupled device (ICCD) detector, adds the capability of fluorescence suppression and depth selection. This paper focuses on the separation of layers with time differences that are much smaller than the

200

 ps

full width at half-maximum gating time of the detector. As an analogue for endolithic life on Mars, Deinococcus radiodurans bacteria were measured through a

2.5

 mm

and

7.5

 mm

top layer of translucent calcite. TRRS spectra were recorded in a backscattering geometry, while stepwise increasing the detector delay in

25

 ps

steps. Through both of these layers, the Raman spectrum of the bacteria’s carotenoids could be detected. Global analysis was used to model a complete time-resolved spectrum of the sample. Using this analysis, the signals could be separated into three components: mineral Raman, bacterial Raman and bacterial fluorescence. The model also corrects for gating differences across the horizontal axis of the ICCD camera. With this approach well-separated Raman spectra were obtained even for the

2.5

mm

calcite layer despite the temporal separation of approximately

20

 ps

, which is much shorter than the

200

 ps

detector gating time. TRRS could be a suitable approach for non-invasive detection of extraterrestrial subsurface biomarkers.
Numerical and experimental study for electron beam welding process of Al6061-T6 material
Authors: Küçüktürk Gökhan , Atkaya Murat
Published: March 2022

Joining the aluminium 6061-T6 alloy (Al6061-T6) using Electron Beam Welding (EBW) wais important, especially in aerospace. Although the EBW method has been used for different materials in the literature, there are a limited number of studies for Al6061-T6 alloy. The study aimed at the weldability and welding quality of 6061-T6 aluminium alloy plates by experimentally and numerically using the EBW technique. A numerical model has been generated to obtain the appropriate voltage, beam current, and welding speed parameters to simulate the EBW process instead of the hit and trial method, which is costly. The numerical model is based on a user-defined function based on the heat source as a function of temperature, welding parameters and material properties. The validation of the model has been compared by obtained width from numerical model and experimental work. Three EBW parameter sets were employed with the numerical model. Three different experimental parameter sets were determined according to the most suitable processing parameter that emerged from the numerical model, and experimental studies were carried out. Experimental studies showed defects in the microstructure due to process defects by unsuitable parameters. While the mechanical strength was 70% of the tensile strength performance compared to the main material, the elongation performance was 75%. The microhardness of the heat affected zone was measured as 84% of the base material, and a hardness reduction of 40% was also observed in the fusion zone. In addition, it showed that using the proper parameter set can eliminate such defects. The application of post-weld heat treatment procedures that can effectively improve the mechanical properties could be investigated in future studies.
Store-operated calcium entry is reduced in spastin-linked hereditary spastic paraplegia
Authors: Rizo Tania , Gebhardt Lisa , Riedlberger Julia , Eberhardt Esther , Fester Lars , Alansary Dalia , Winkler Jürgen , Turan Soeren , Arnold Philipp , Niemeyer Barbara A , Fischer Michael J M , Winner Beate
Published: March 2022

Pathogenic variants in SPAST, the gene coding for spastin, are the single most common cause of hereditary spastic paraplegia, a progressive motor neuron disease. Spastin regulates key cellular functions, including microtubule-severing and endoplasmic reticulum-morphogenesis. However, it remains unclear how alterations in these cellular functions due to SPAST pathogenic variants result in motor neuron dysfunction. Since spastin influences both microtubule network and endoplasmic reticulum structure, we hypothesized that spastin is necessary for the regulation of Ca2+ homeostasis via store-operated calcium entry.

Here, we show that the lack of spastin enlarges the endoplasmic reticulum and reduces store-operated calcium entry. In addition, elevated levels of different spastin variants induced clustering of STIM1 within the endoplasmic reticulum, altered the transport of STIM1 to the plasma membrane and reduced store-operated calcium entry, which could be rescued by exogenous expression of STIM1. Importantly, store-operated calcium entry was strongly reduced in induced pluripotent stem cell-derived neurons from hereditary spastic paraplegia patients with pathogenic variants in SPAST resulting in spastin haploinsufficiency. These neurons developed axonal swellings in response to lack of spastin. We were able to rescue both store-operated calcium entry and axonal swellings in SPAST patient neurons by restoring spastin levels, using CRISPR/Cas9 to correct the pathogenic variants in SPAST.

These findings demonstrate that proper amounts of spastin are a key regulatory component for store-operated calcium entry mediated Ca2+ homeostasis and suggest store-operated calcium entry as a disease relevant mechanism of spastin-linked motor neuron disease.