Twitter's Role in Combating the Magnetic Vaccine Conspiracy Theory: Social Network Analysis of Tweets.

BACKGROUND: The popularity of the magnetic vaccine conspiracy theory and other conspiracy theories of a similar nature creates challenges to promoting vaccines and disseminating accurate health information. OBJECTIVE: Health conspiracy theories are gaining in popularity. This study's objective was to evaluate the Twitter social media network related to the magnetic vaccine conspiracy theory and apply social capital theory to analyze the unique social structures of influential users. As a strategy for web-based public health surveillance, we conducted a social network analysis to identify the important opinion leaders sharing the conspiracy, the key websites, and the narratives. METHODS: A total of 18,706 tweets were retrieved and analyzed by using social network analysis. Data were retrieved from June 1 to June 13, 2021, using the keyword vaccine magnetic. Tweets were retrieved via a dedicated Twitter application programming interface. More specifically, the Academic Track application programming interface was used, and the data were analyzed by using NodeXL Pro (Social Media Research Foundation) and Gephi. RESULTS: There were a total of 22,762 connections between Twitter users within the data set. This study found that the most influential user within the network consisted of a news account that was reporting on the magnetic vaccine conspiracy. There were also several other users that became influential, such as an epidemiologist, a health economist, and a retired sports athlete who exerted their social capital within the network. CONCLUSIONS: Our study found that influential users were effective broadcasters against the conspiracy, and their reach extended beyond their own networks of Twitter followers. We emphasize the need for trust in influential users with regard to health information, particularly in the context of the widespread social uncertainty resulting from the COVID-19 pandemic, when public sentiment on social media may be unpredictable. This study highlights the potential of influential users to disrupt information flows of conspiracy theories via their unique social capital.

Is #SDG13 Trending Online? Insights from Climate Change Discussions on Twitter.

Anthropogenic activities over the past few decades have led to increased vulnerability of environmental and ecological stability on this planet. Accelerated climate change is one such subset of the environmental problems that threatens the very existence of humankind in twenty first century. Governments, United Nations (UN) and other humanitarian agencies across the globe have developed and devised strategies for climate action that requires grater public awareness and actions. Social media has played a vital role in information dissemination and raising public awareness of climate change in the digital era. To this aid, an upsurge has been documented in recent times regarding discussions over climate change with #SDG13 (Sustainable Development Goals) at its epicenter. Following the principles of Actor Network Theory (ANT) we analyzed a large volume of Twitter data to understand general citizens' perception and attitude towards climate change. Our findings unveil people's opinion on causes and concerns related to barriers of adopting a more sustainable consumption and lifestyle practice. There is also a growing apathy towards sluggish government actions that makes little difference. People were also found to exchange innovative concepts and measures towards mitigating the effects of climate change.

The #VaccinesWork Hashtag on Twitter in the Context of the COVID-19 Pandemic: Network Analysis.

BACKGROUND: Vaccination is one of the most successful public health interventions for the prevention of COVID-19. Toward the end of April 2021, UNICEF (United Nations International Children's Emergency Fund), alongside other organizations, were promoting the hashtag #VaccinesWork. OBJECTIVE: The aim of this paper is to analyze the #VaccinesWork hashtag on Twitter in the context of the COVID-19 pandemic, analyzing the main messages shared and the organizations involved. METHODS: The data set used in this study consists of 11,085 tweets containing the #VaccinesWork hashtag from the 29th to the 30th of April 2021. The data set includes tweets that may not have the hashtag but were replies or mentions in those tweets. The data were retrieved using NodeXL, and the network graph was laid out using the Harel-Koren fast multiscale layout algorithm. RESULTS: The study found that organizations such as the World Health Organization, UNICEF, and Gavi were the key opinion leaders and had a big influence on the spread of information among users. Furthermore, the most shared URLs belonged to academic journals with a high impact factor. Provaccination users had other vaccination-promoting hashtags in common, not only in the COVID-19 scenario. CONCLUSIONS: This study investigated the discussions surrounding the #VaccinesWork hashtag. Social media networks containing conspiracy theories tend to contain dubious accounts leading the discussions and are often linked to unverified information. This kind of analysis can be useful to detect the optimal moment for launching health campaigns on Twitter.

Beyond isolated cells: microfluidic transport of large tissue for pancreatic cancer diagnosis.

For cancer diagnoses, core biopsies (CBs) obtained from patients using coring needles (CNs) are traditionally visualized and assessed on microscope slides by pathologists after samples are processed and sectioned. A fundamental gain in optical information (i.e., diagnosis/staging) may be achieved when whole, unsectioned CBs (L = 5-20, D = 0.5-2.0 mm) are analyzed in 3D. This approach preserves CBs for traditional pathology and maximizes the diagnostic potential of patient samples. To bridge CNs/CBs with imaging, our group developed a microfluidic device that performs biospecimen preparation on unsectioned CBs for pathology. The ultimate goal is an automated and rapid point-of-care system that aids pathologists by processing tissue for advanced 3D imaging platforms. An inherent, but essential device feature is the microfluidic transport of CBs, which has not been previously investigated. Early experiments demonstrated proof-of-concept: pancreas CBs (D = 0.3-2.0 mm) of set lengths were transported in straight/curved microchannels, but dimensional tolerance and flow rates were variable, and preservation of CB integrity was uncontrolled. A second study used metal cylinder substitutes (L = 10, D = 1 mm) in microchannels to understand the transport mechanism. However, CBs are imperfectly shaped, rough, porous and viscoelastic. In this study, fresh/formalin-fixed porcine and human pancreas CBs were deposited into our device through a custom interface using clinical CNs. CB integrity (i.e., sample viability) may be assessed at every stage using an optomechanical metric: physical breaks were determined when specimen intensity profile data deviated beyond xavg + 2σ. Flow rates for human CBs were determined for several CNs, and microfluidic transport of fresh and formalin-fixed CBs was analyzed.

Contraction-Induced Changes in Hydrogen Bonding of Muscle Hydration Water.

Protein-water interaction plays a crucial role in protein dynamics and hence function. To study the chemical environment of water and proteins with high spatial resolution, synchrotron radiation-Fourier transform infrared (SR-FTIR) spectromicroscopy was used to probe skeletal muscle myofibrils. Observing the OH stretch band showed that water inside of relaxed myofibrils is extensively hydrogen-bonded with little or no free OH. In higher-resolution measurements obtained with single isolated myofibrils, the water absorption peaks were relatively higher within the center region of the sarcomere compared to those in the I-band region, implying higher hydration capacity of thick filaments compared to the thin filaments. When specimens were activated, changes in the OH stretch band showed significant dehydrogen bonding of muscle water; this was indicated by increased absorption at ∼3480 cm-1 compared to relaxed myofibrils. These contraction-induced changes in water were accompanied by splitting of the amide I (C=O) peak, implying that muscle proteins transition from α-helix to ß-sheet-rich structures. Hence, muscle contraction can be characterized by a loss of order in the muscle-protein complex, accompanied by a destructuring of hydration water. The findings shed fresh light on the molecular mechanism of muscle contraction and motor protein dynamics.

Feasibility of a hybrid elastographic-microfluidic device to rapidly process and assess pancreatic cancer biopsies for pathologists.

In this study, our collaborative research group explored the possibility of incorporating ultrasound elastography technology with a microfluidic device that is designed to prepare fine needle core biopsies (CBs; L=0.5-2.0 cm, D=0.4-1.2 mm) for pancreatic cancer diagnosis. For the first time, elastographic techniques were employed to measure shear wave velocity in fresh (3.7 m/s) and formalin-fixed (14.7 m/s) pancreatic CBs. Shear wave velocity did not vary whether fixed specimens were free on a microscope slide, or constrained within glass microfluidic channels: 11.5±1.9 v. 11.8±2.1 m/s. 4% agarose inclusions were also embedded within 1% agarose hydrogels to simulate cysts, neoplastic, or necrotic tissue within CBs. Inclusions were successfully visualized and measured using optical coherence elastography. These preliminary experiments demonstrate in a rudimentary fashion that elastographic measurements of pancreatic CBs may be incorporated with our microfluidic device. The rapid mapping of CB stiffness may provide qualitative spatial information for pathologists to determine a more accurate diagnosis for patients.

Charge-based forces at the Nafion-water interface.

Interfacial water lying next to hydrophilic surfaces has been shown to be spectroscopically, mechanically, and electrically distinct from bulk water. Interfacial water has also been shown to exclude negatively and positively charged microspheres and has thus become known as the "exclusion zone". Measurements have demonstrated that exclusion zones exhibit a negative electrical potential on the order of -100 mV relative to bulk water, with a corresponding distribution of positive protons in the bulk water region beyond the exclusion zone. This separation of charge is hypothesized to create an electrostatic force between the exclusion zone and the proton-enriched zone beyond. To test this hypothesis, a hydrophilic Nafion ring was attached to the tip of a deflectable ribbonlike force sensor. The sensor was designed to obstruct the flow of protons from one side of the lever to the other, so that any proton-based force would remain unilateral. pH-sensitive dye measurements confirmed that the protons were largely confined to one side. When the lever assembly was exposed to water, the sensor deflected toward the protons. Over a period of 20 min, deflection amounted to approximately 20 µm, corresponding to a force of approximately 22 µN. Hence, electrostatic forces are confirmed. If exclusion zones exist ubiquitously at hydrophilic surfaces, including biological surfaces, then the resulting electrostatic forces may play significant roles in many biological phenomena including adhesion and protein folding.

Automatic step-detection algorithm for analysis of sarcomere dynamics.

Motile systems exhibit a stepwise nature, seen most prominently in muscle contraction. A novel algorithm has been developed that detects steps automatically in sarcomere-length change data and computes their size. The method is based on a nonlinear filter and a step detection protocol that detects local slope values in comparison to a threshold. The algorithm was first evaluated using artificial data with various degrees of Gaussian noise. Steps were faithfully detected even with significant noise. With actual data, the algorithm detected 2.7 nm steps and integer multiples thereof. The results confirm a quantal 2.7 nm step-size reported earlier. As stepwise phenomena become increasingly evident, automatic step-detection algorithms become increasingly useful since the limiting factor is almost always noise. The algorithm presented here offers a versatile and accurate tool that should be useful not only within muscle contraction and motility fields, but in fields which quantal phenomena play a role.

Indiplon is a high-affinity positive allosteric modulator with selectivity for alpha1 subunit-containing GABAA receptors.

Indiplon (NBI 34060) is a novel pyrazolopyrimidine currently in development for the treatment of insomnia. We have previously shown that indiplon exhibits high-affinity binding to native GABA(A) receptors from rat brain and acts as a positive allosteric modulator of GABA(A) receptor currents in cultured rat neurons (Sullivan et al., 2004). In this study, we examined the GABA(A) receptor alpha subunit selectivity of indiplon using electrophysiological techniques to record GABA-activated chloride currents from recombinant rodent GABA(A) receptors expressed in human embryonic kidney 293 cells. Indiplon potentiated the GABA-activated chloride current in recombinant GABA(A) receptors in a dose-dependent and reversible manner and was approximately 10-fold selective for alpha1 subunit-containing receptors over GABA(A) receptors containing alpha2, alpha3, or alpha5 subunits. The EC(50) values were 2.6, 24, 60, and 77 nM for alpha1beta2gamma2, alpha2beta2gamma2, alpha3beta3gamma2, and alpha5beta2gamma2 receptors, respectively. Indiplon was approximately 10 times more potent than zolpidem and zopiclone and >100 times more potent than zaleplon. Moreover, indiplon, up to 1 microM, did not potentiate GABA(A) receptors composed of alpha4beta2gamma2 and alpha6beta2gamma2 subunits. This mechanism of action is proposed to underlie the sedative-hypnotic effects of indiplon in animals and humans.

Sarcomere strain and heterogeneity correlate with injury to frog skeletal muscle fiber bundles.

Sarcomere length and first-order diffraction line width were measured by laser diffraction during elongation of activated frog tibialis anterior muscle fiber bundles (i.e., eccentric contraction) at nominal fiber strains of 10, 25, or 35% (n = 18) for 10 successive contractions. Tetanic tension, measured just before each eccentric contraction, differed significantly among strain groups and changed dramatically during the 10-contraction treatment (P < 0.01). Average maximum tetanic tension for the three groups measured before any treatment was 203.7 +/- 6.8 kN/m2, but after the 10-eccentric contraction sequence decreased to 180.3 +/- 3.8, 125.1 +/- 7.8, and 78.3 +/- 5.1 kN/m2 for the 10, 25, and 35% strain groups, respectively (P < 0.0001). Addition of 10 mM caffeine to the bathing medium decreased the loss of tetanic tension in the 10% strain group but had only a minimal effect on either the 25 or 35% strain groups. Diffraction pattern line width, a measure of sarcomere length heterogeneity, increased significantly with muscle activation and then continued to increase with successive stretches of the activated muscle. Line width increase after each stretch was significantly correlated with the lower yield tension of the successive contractile record. These data demonstrate a direct association and, perhaps, a causal relationship between sarcomere strain and fiber bundle injury. They also demonstrate that muscle injury is accompanied by a progressive increase in sarcomere length heterogeneity, yielding lower yield tension as injury progresses.