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1.
Data Brief ; 54: 110459, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38774246

ABSTRACT

This article introduces an openly accessible dataset aimed at supporting energy system modelling of decarbonisation pathways in the Philippines. The dataset was compiled through an extensive literature review, incorporating information from various sources such as the Philippines Department of Energy, academic publications, and international organisations. To ensure compatibility with OSeMOSYS modelling requirements, the data underwent processing and standardisation. It includes power plant data covering existing capacity from classified by grid, off-grid, and planned additions, as well as historical generation data. Additionally, the dataset provides historical and projected electricity demand from 2015 to 2050 segmented by sectors. It also offers technical potential estimates for fossil fuels and renewable energy sources, along with key techno-economic parameters for emerging technologies like floating solar PV, in-stream tidal, and offshore wind. The dataset is freely available on Zenodo, empowering researchers, policymakers, and private-sector actors to conduct independent energy modelling and analyses aligned with the U4RIA framework principles. Its open access encourages collaboration and facilitates informed decision-making to advance a sustainable energy future not only for the Philippines but also for broader global contexts.

2.
Data Brief ; 54: 110323, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38586150

ABSTRACT

Indonesia's emission reduction commitment and clean energy transition target emphasises the importance of energy system modelling for analysing and projecting Indonesia's capacity, resource availability, and future conditions in achieving these objectives. Utilising energy systems modelling based on adequate and reliable data enables policymakers to select the most optimal alternatives in energy planning. Aligned with the U4RIA (Ubuntu, Retrievability, Repeatability, Reconstructability, Interoperability, Auditability) concept, this database may facilitate various related stakeholders in obtaining this comprehensive and detailed energy data, while the data gathering and processing can also be applied to other developing countries. This country-specific dataset covers the historical data of electricity generation, demand, installed capacity, capacity factor, technical lifetime, renewable energy potentials, costs, and its projections up to 2050. The data in this article is ready to be used for energy system and modelling research.

3.
Data Brief ; 52: 109822, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38076470

ABSTRACT

Hydrogen is globally acknowledged as a versatile energy carrier crucial for decarbonization in multiple sectors. Many countries have initiated the development of national hydrogen roadmaps and strategies, recognizing hydrogen as a strategic resource for achieving sustainable energy transitions. Formulating these guidelines for future action demands a solid technical foundation to facilitate well-informed decision-making. Energy system modelling has emerged as a significant scientific tool to assist governments and ministries in designing hydrogen pathways assessments based on scientific outcomes. The first step in the modelling process involves gathering, curating, and managing techno-economic data, a process that is often time-consuming and hindered by the unavailability and inaccessibility of data sources. This paper introduces an open techno-economic dataset encompassing key technologies within the hydrogen supply chain, spanning from production to end-use applications. Energy modelers, researchers, policymakers, and stakeholders can leverage this dataset for energy planning models, with a specific focus on hydrogen pathways. The presented data is designed to promote modelling studies that are retrievable, reusable, repeatable, reconstructable, interoperable, and auditable (U4RIA). This enhanced transparency aims to foster greater public trust, scientific reproducibility, and increased collaboration amongst academia, industry, and government in producing technical reports that underpin national hydrogen roadmaps and strategies.

4.
ACS Appl Mater Interfaces ; 15(50): 57960-57969, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37861980

ABSTRACT

The reliable and regular modification of the surface properties of substrates plays a crucial role in material research and the development of functional surfaces. A key aspect of this is the development of the surface pores and topographies. These can confer specific advantages such as high surface area as well as specific functions such as hydrophobic properties. Here, we introduce a combination of nanoscale self-assembled block-copolymer-based metal oxide masks with optimized deep reactive ion etching (DRIE) of silicon to permit the fabrication of porous topographies with aspect ratios of up to 50. Following the evaluation of our procedure and involved parameters using various techniques, such as AFM or SEM, the suitability of our features for applications relying on high light absorption as well as efficient thermal management is explored and discussed in further detail.

5.
Data Brief ; 48: 109268, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37383789

ABSTRACT

Decarbonization pathways have emerged as a pivotal element of global climate change mitigation strategies. Energy system modelling is widely recognized as a tool to support the design of informed energy decarbonization policies. However, the development of energy models heavily relies on high-quality input data, which may pose significant challenges in developing countries where data accessibility is limited, incomplete, outdated, or inadequate. Moreover, while models may exist in countries, these are not publicly available; therefore, details cannot be retrieved, repeated, reconstructed, interoperable or auditable (U4RIA). This paper presents an open techno-economic energy dataset for Colombia that is U4RIA-compliant as it can be used transparently to model decarbonization pathways and support energy planning in the country. Despite being country-specific, most of the data is technology-based and thus applicable to other countries. Diverse sources, assumptions, and modelling guidelines are described to facilitate the creation of new datasets. The dataset enhances the availability of energy data for policymakers, stakeholders, and researchers, not only in Colombia but also in other developing countries.

6.
Nat Methods ; 20(4): 569-579, 2023 04.
Article in English | MEDLINE | ID: mdl-36997816

ABSTRACT

The ability to quantify structural changes of the endoplasmic reticulum (ER) is crucial for understanding the structure and function of this organelle. However, the rapid movement and complex topology of ER networks make this challenging. Here, we construct a state-of-the-art semantic segmentation method that we call ERnet for the automatic classification of sheet and tubular ER domains inside individual cells. Data are skeletonized and represented by connectivity graphs, enabling precise and efficient quantification of network connectivity. ERnet generates metrics on topology and integrity of ER structures and quantifies structural change in response to genetic or metabolic manipulation. We validate ERnet using data obtained by various ER-imaging methods from different cell types as well as ground truth images of synthetic ER structures. ERnet can be deployed in an automatic high-throughput and unbiased fashion and identifies subtle changes in ER phenotypes that may inform on disease progression and response to therapy.


Subject(s)
Endoplasmic Reticulum , Semantics , Endoplasmic Reticulum/metabolism
7.
Bioengineering (Basel) ; 9(11)2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36421119

ABSTRACT

The culturing and investigation of individual marine specimens in lab environments is crucial to further our understanding of this highly complex ecosystem. However, the obtained results and their relevance are often limited by a lack of suitable experimental setups enabling controlled specimen growth in a natural environment while allowing for precise monitoring and in-depth observations. In this work, we explore the viability of a microfluidic device for the investigation of the growth of the alga Saccharina latissima to enable high-resolution imaging by confining the samples, which usually grow in 3D, to a single 2D plane. We evaluate the specimen's health based on various factors such as its growth rate, cell shape, and major developmental steps with regard to the device's operating parameters and flow conditions before demonstrating its compatibility with state-of-the-art microscopy imaging technologies such as the skeletonisation of the specimen through calcofluor white-based vital staining of its cell contours as well as the immunolocalisation of the specimen's cell wall. Furthermore, by making use of the on-chip characterisation capabilities, we investigate the influence of altered environmental illuminations on the embryonic development using blue and red light. Finally, live tracking of fluorescent microspheres deposited on the surface of the embryo permits the quantitative characterisation of growth at various locations of the organism.

9.
Biomech Model Mechanobiol ; 20(6): 2287-2297, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34431032

ABSTRACT

The sensory hairs of the Venus flytrap (Dionaea muscipula Ellis) detect mechanical stimuli imparted by their prey and fire bursts of electrical signals called action potentials (APs). APs are elicited when the hairs are sufficiently stimulated and two consecutive APs can trigger closure of the trap. Earlier experiments have identified thresholds for the relevant stimulus parameters, namely the angular displacement [Formula: see text] and angular velocity [Formula: see text]. However, these experiments could not trace the deformation of the trigger hair's sensory cells, which are known to transduce the mechanical stimulus. To understand the kinematics at the cellular level, we investigate the role of two relevant mechanical phenomena: viscoelasticity and intercellular fluid transport using a multi-scale numerical model of the sensory hair. We hypothesize that the combined influence of these two phenomena and [Formula: see text] contribute to the flytrap's rate-dependent response to stimuli. In this study, we firstly perform sustained deflection tests on the hair to estimate the viscoelastic material properties of the tissue. Thereafter, through simulations of hair deflection tests at different loading rates, we were able to establish a multi-scale kinematic link between [Formula: see text] and the cell wall stretch [Formula: see text]. Furthermore, we find that the rate at which [Formula: see text] evolves during a stimulus is also proportional to [Formula: see text]. This suggests that mechanosensitive ion channels, expected to be stretch-activated and localized in the plasma membrane of the sensory cells, could be additionally sensitive to the rate at which stretch is applied.


Subject(s)
Droseraceae/physiology , Biological Transport , Biomechanical Phenomena/physiology , Computer Simulation , Elasticity , Finite Element Analysis , Models, Biological , Physical Stimulation , Rheology , Viscosity
10.
Anal Chem ; 93(28): 9760-9770, 2021 07 20.
Article in English | MEDLINE | ID: mdl-34228921

ABSTRACT

Acoustically excited microstructures have demonstrated significant potential for small-scale biomedical applications by overcoming major microfluidic limitations. Recently, the application of oscillating microbubbles has demonstrated their superiority over acoustically excited solid structures due to their enhanced acoustic streaming at low input power. However, their limited temporal stability hinders their direct applicability for industrial or clinical purposes. Here, we introduce the embedded microbubble, a novel acoustofluidic design based on the combination of solid structures (poly(dimethylsiloxane)) and microbubbles (air-filled cavity) to combine the benefits of both approaches while minimizing their drawbacks. We investigate the influence of various design parameters and geometrical features through numerical simulations and experimentally evaluate their manipulation capabilities. Finally, we demonstrate the capabilities of our design for microfluidic applications by investigating its mixing performance as well as through the controlled rotational manipulation of individual HeLa cells.


Subject(s)
Microbubbles , Microfluidics , Acoustics , HeLa Cells , Humans
11.
Micromachines (Basel) ; 12(5)2021 May 10.
Article in English | MEDLINE | ID: mdl-34068670

ABSTRACT

Deep reactive ion etching (DRIE) with the Bosch process is one of the key procedures used to manufacture micron-sized structures for MEMS and microfluidic applications in silicon and, hence, of increasing importance for miniaturisation in biomedical research. While guaranteeing high aspect ratio structures and providing high design flexibility, the etching procedure suffers from reactive ion etching lag and often relies on complex oxide masks to enable deep etching. The reactive ion etching lag, leading to reduced etch depths for features exceeding an aspect ratio of 1:1, typically causes a height difference of above 10% for structures with aspect ratios ranging from 2.5:1 to 10:1, and, therefore, can significantly influence subsequent device functionality. In this work, we introduce an optimised two-step Bosch process that reduces the etch lag to below 1.5%. Furthermore, we demonstrate an improved three-step Bosch process, allowing the fabrication of structures with 6 µm width at depths up to 180 µm while maintaining their stability.

12.
Nat Commun ; 12(1): 2583, 2021 05 10.
Article in English | MEDLINE | ID: mdl-33972516

ABSTRACT

Quantitative micromechanical characterization of single cells and multicellular tissues or organisms is of fundamental importance to the study of cellular growth, morphogenesis, and cell-cell interactions. However, due to limited manipulation capabilities at the microscale, systems used for mechanical characterizations struggle to provide complete three-dimensional coverage of individual specimens. Here, we combine an acoustically driven manipulation device with a micro-force sensor to freely rotate biological samples and quantify mechanical properties at multiple regions of interest within a specimen. The versatility of this tool is demonstrated through the analysis of single Lilium longiflorum pollen grains, in combination with numerical simulations, and individual Caenorhabditis elegans nematodes. It reveals local variations in apparent stiffness for single specimens, providing previously inaccessible information and datasets on mechanical properties that serve as the basis for biophysical modelling and allow deeper insights into the biomechanics of these living systems.


Subject(s)
Imaging, Three-Dimensional/methods , Micromanipulation/instrumentation , Micromanipulation/methods , Microscopy, Atomic Force/methods , Single-Cell Analysis/instrumentation , Single-Cell Analysis/methods , Acoustics , Animals , Biomechanical Phenomena , Caenorhabditis elegans/anatomy & histology , Caenorhabditis elegans/cytology , Cell Wall/ultrastructure , Lilium/cytology , Microscopy, Electron, Scanning , Morphogenesis , Plant Cells , Pollen/cytology , Pollen/ultrastructure
13.
PLoS Biol ; 18(7): e3000740, 2020 07.
Article in English | MEDLINE | ID: mdl-32649659

ABSTRACT

The carnivorous Venus flytrap catches prey by an ingenious snapping mechanism. Based on work over nearly 200 years, it has become generally accepted that two touches of the trap's sensory hairs within 30 s, each one generating an action potential, are required to trigger closure of the trap. We developed an electromechanical model, which, however, suggests that under certain circumstances one touch is sufficient to generate two action potentials. Using a force-sensing microrobotic system, we precisely quantified the sensory-hair deflection parameters necessary to trigger trap closure and correlated them with the elicited action potentials in vivo. Our results confirm the model's predictions, suggesting that the Venus flytrap may be adapted to a wider range of prey movements than previously assumed.


Subject(s)
Droseraceae/physiology , Touch Perception/physiology , Action Potentials/physiology , Biomechanical Phenomena , Electricity , Models, Biological , Physical Stimulation , Torque
14.
Int J Mol Sci ; 22(1)2020 Dec 30.
Article in English | MEDLINE | ID: mdl-33396579

ABSTRACT

Insects fall prey to the Venus flytrap (Dionaea muscipula) when they touch the sensory hairs located on the flytrap lobes, causing sudden trap closure. The mechanical stimulus imparted by the touch produces an electrical response in the sensory cells of the trigger hair. These cells are found in a constriction near the hair base, where a notch appears around the hair's periphery. There are mechanosensitive ion channels (MSCs) in the sensory cells that open due to a change in membrane tension; however, the kinematics behind this process is unclear. In this study, we investigate how the stimulus acts on the sensory cells by building a multi-scale hair model, using morphometric data obtained from µ-CT scans. We simulated a single-touch stimulus and evaluated the resulting cell wall stretch. Interestingly, the model showed that high stretch values are diverted away from the notch periphery and, instead, localized in the interior regions of the cell wall. We repeated our simulations for different cell shape variants to elucidate how the morphology influences the location of these high-stretch regions. Our results suggest that there is likely a higher mechanotransduction activity in these 'hotspots', which may provide new insights into the arrangement and functioning of MSCs in the flytrap.


Subject(s)
Droseraceae/physiology , Insecta/physiology , Mechanotransduction, Cellular/physiology , Plant Leaves/physiology , Algorithms , Animals , Biomechanical Phenomena , Cell Membrane Structures/physiology , Droseraceae/cytology , Electromagnetic Phenomena , Plant Leaves/cytology , Signal Transduction/physiology
15.
New Phytol ; 220(1): 187-195, 2018 10.
Article in English | MEDLINE | ID: mdl-29905972

ABSTRACT

Physical forces are involved in the regulation of plant development and morphogenesis by translating mechanical stress into the modification of physiological processes, which, in turn, can affect cellular growth. Pollen tubes respond rapidly to external stimuli and provide an ideal system to study the effect of mechanical cues at the single-cell level. Here, pollen tubes were exposed to mechanical stress while monitoring the reconfiguration of their growth and recording the generated forces in real-time. We combined a lab-on-a-chip device with a microelectromechanical systems (MEMS)-based capacitive force sensor to mimic and quantify the forces that are involved in pollen tube navigation upon confronting mechanical obstacles. Several stages of obstacle avoidance were identified, including force perception, growth adjustment and penetration. We have experimentally determined the perceptive force threshold, which is the force threshold at which the pollen tube reacts to an obstacle, for Lilium longiflorum and Arabidopsis thaliana. In addition, the method we developed provides a way to calculate turgor pressure based on force and optical data. Pollen tubes sense physical barriers and actively adjust their growth behavior to overcome them. Furthermore, our system offers an ideal platform to investigate intracellular activity during force perception and growth adaption in tip growing cells.


Subject(s)
Pollen Tube/physiology , Arabidopsis/growth & development , Arabidopsis/physiology , Biomechanical Phenomena , Micro-Electrical-Mechanical Systems , Pollen Tube/growth & development , Pressure , Species Specificity
16.
Curr Genomics ; 17(1): 70-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27013925

ABSTRACT

Vesicoureteral reflux (VUR) is the retrograde passage of urine from the bladder to the upper urinary tract. It is the most common congenital urological anomaly affecting 1-2% of children and 30-40% of patients with urinary tract infections. VUR is a major risk factor for pyelonephritic scarring and chronic renal failure in children. It is the result of a shortened intravesical ureter with an enlarged or malpositioned ureteric orifice. An ectopic embryonal ureteric budding development is implicated in the pathogenesis of VUR, which is a complex genetic developmental disorder. Many genes are involved in the ureteric budding formation and subsequently in the urinary tract and kidney development. Previous studies demonstrate an heterogeneous genetic pattern of VUR. In fact no single major locus or gene for primary VUR has been identified. It is likely that different forms of VUR with different genetic determinantes are present. Moreover genetic studies of syndromes with associated VUR have revealed several possible candidate genes involved in the pathogenesis of VUR and related urinary tract malformations. Mutations in genes essential for urinary tract morphogenesis are linked to numerous congenital syndromes, and in most of those VUR is a feature. The Authors provide an overview of the developmental processes leading to the VUR. The different genes and signaling pathways controlling the embryonal urinary tract development are analyzed. A better understanding of VUR genetic bases could improve the management of this condition in children.

17.
Minerva Pediatr ; 65(1): 77-82, 2013 Feb.
Article in Italian | MEDLINE | ID: mdl-23422576

ABSTRACT

AIM: The authors report the results of a retrospective study carried out with family pediatricians (PDF) in the area of Naples to verify the epidemiology of cryptorchidism and retractile testis, the therapeutic strategy adopted and to assess whether they were in agreement with the data of the scientific literature. METHODS: The study enrolled 6880 children, aged between 0-14 years, till March 2007; among those were recruited the patients with a diagnosis of cryptorchid and/or retractile testis. A patient schedule was completed with the affected side or bilaterality, age at diagnosis, type of treatment and the number of ascent retractile testis. RESULTS: A purely descriptive analysis of the data was carried out: 81 patients were diagnosed with cryptorchid patients (1.18%) and 116 with retractile testis (1.68%). In 11 cases an ascent testicle was detected (9.48%). Forty-nine of the 81 cryptorchid patients (60.49%) were diagnosed in the age group of 0-2 years, 25 (30.86%) between 2-4 years and 7 (8.64 %) between 4-8 years. The hormonal therapy associated with surgery was mainly adopted in cryptorchid patients (35 patients). CONCLUSION: The incidence of cryptorchidism in the area of Naples (1.18%) has not changed significantly. Only 60.49% of patients have been treated in an appropriate age group (0-2 years). The survey confirms the need to follow up the retractile testes for the possibility of definitive ascent in the inguinal canal. The study highlights the need for early diagnosis and treatment of this disease.


Subject(s)
Cryptorchidism/epidemiology , Cryptorchidism/therapy , Adolescent , Child , Child, Preschool , Humans , Infant , Italy/epidemiology , Male , Retrospective Studies , Testis/abnormalities
19.
Eur J Pediatr Surg ; 20(6): 366-70, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20954105

ABSTRACT

AIM: We report our experience with pneumovesicoscopic cross-trigonal ureteral reimplantation to correct primary vesicoureteral reflux (VUR) in children. MATERIAL AND METHODS: 14 children (10 girls, 4 boys, aged 4 to 12 years) with persistent VUR ≥ grade III (5 bilateral, 19 refluxing ureters) underwent pneumovesicoscopic Cohen's cross-trigonal reimplantation. Under cystoscopic control, a first midline 5-mm trocar was introduced for a 0°\30° telescope at the dome of the bladder, and 2 left and right 3- or 5-mm trocars were inserted through the anterolateral wall. The ureter was freed by creating a sharp plane between the detrusor muscle and the ureteral wall. If necessary, the ureter was tailored outside the bladder. Submucosal tunnel(s) were prepared with the help of scissors and graspers. The detrusor at the site of the ureter mobilization was repaired and ureteroneocystomy was performed using 4-5 interrupted absorbable sutures. A 12-Ch Foley catheter was introduced at the site of the dome port. The urethral and suprapubic catheters were removed 2-3 days after the procedure and the patients were discharged on day 3. RESULTS: One boy developed mild suprapubic emphysema postoperatively. Mean operating time was 136 min (range 80-230 min). No patient required conversion to the open technique. Renal US, VCUG, and MAG3 radionuclide scans were obtained in all patients between 3-6 months postoperatively, and provided evidence of reflux resolution in 13 out of 14 patients. CONCLUSION: Our experience seems to confirm that pneumovesicoscopic cross-trigonal ureteral reimplantation can be performed safely and effectively.


Subject(s)
Cystoscopy , Ureter/surgery , Vesico-Ureteral Reflux/surgery , Child , Child, Preschool , Female , Humans , Male , Replantation
20.
J Pediatr Urol ; 6(6): 550-4, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20106723

ABSTRACT

OBJECT: To retrospectively review the value of laparoscopy in the management of impalpable testis. MATERIALS AND METHODS: In 1993-2006, 182 laparoscopies for impalpable testis were performed for a total of 194 testicular units. Five laparoscopic findings were considered: testicular ectopia, intra-abdominal testis, and cord structures that are blind ending, completely absent (agenesis) or entering the internal inguinal ring. RESULTS: In 62 cases an intra-abdominal testis was found; 18 were classified as high and managed by a laparoscopic Fowler-Stephens procedure. Cord structures entering the inguinal ring were observed in 77 patients and 45 underwent an inguinal exploration: a testis was found in 12 cases and in 33 a remnant was excised. In 35 cases, intra-abdominal blind ending vas and vessels were observed and eight showed testicular agenesis. No major surgical complications were recorded. Follow up ranged from 1 to 3 years. CONCLUSIONS: Our study confirms the value of laparoscopy in the management of non-palpable testis, providing a definitive diagnosis by the direct view of spermatic bundle and testis. Ninety-three patients were managed by laparoscopy only, and in 44 it was essential for the subsequent surgical approach. When the internal inguinal ring is patent and/or normal spermatic vessels are present an inguinal exploration is mandatory.


Subject(s)
Cryptorchidism/surgery , Laparoscopy , Child , Child, Preschool , Cryptorchidism/diagnosis , Cryptorchidism/pathology , Humans , Infant , Laparoscopy/methods , Male
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