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The unique properties of fluorine-containing organic compounds make fluorine substitution attractive for the development of pharmaceuticals and various specialty materials, which have inspired the evolution of diverse C-F bond activation techniques. Although many advances have been made in functionalizations of activated C-F bonds utilizing transition metal complexes, there are fewer approaches available for nonactivated C-F bonds due to the difficulty in oxidative addition of transition metals to the inert C-F bonds. In this regard, using Lewis acid to abstract the fluoride and light/radical initiator to generate the radical intermediate have emerged as powerful tools for activating those inert C-F bonds. Meanwhile, these transition-metal-free processes are greener, economical, and for the pharmaceutical industry, without heavy metal residues. This review provides an overview of recent C-F bond activations and functionalizations under transition-metal-free conditions. The key mechanisms involved are demonstrated and discussed in detail. Finally, a brief discussion on the existing limitations of this field and our perspective are presented.

The young stellar source HH 30 is a textbook example of an ionic optical jet originating from a disk in an edge-on system shown by the Hubble Space Telescope. It has a remnant envelope in 12CO observed by the Atacama Large Millimeter/submillimeter Array. The optical jet is characterized by its narrow appearance, large line width at the base, and high temperature inferred from line diagnostics. Three featured structures can be identified, most evident in the transverse position–velocity diagrams: an extremely-high-velocity wide-angle wind component with large spectral widths in the optical, a very-low-velocity ambient surrounding medium seen in 12CO, and a low-velocity region traced by 12CO nested both in velocity and location between the primary wind and ambient environment. A layered cavity with multiple shells forms nested morphological and kinematic structures around the optical jet. The atomic gas originating from the innermost region of the disk attains a sufficient temperature and ionization to emit brightly in forbidden lines as an optical jet. The wide-angle portion expands, forming a low-density cavity. The filamentary 12CO encompassing the wind cavity is mixed and advected inward through the action of the magnetic interplay of the wide-angle wind with the molecular ambient medium. The magnetic interplay results in the layered shells penetrating deeply into the vast cavity of tenuous atomic wind material. The HH 30 system is an ideal manifestation of the unified wind model of Shang et al. (2020, 2023), with clearly distinguishable atomic and molecular species mixed through the atomic lightly ionized magnetized wind and the surrounding cold molecular ambient material.

Purpose This study aims to fill a conceptual gap by identifying the dimensions of green experiential quality and empirically examining the interrelationships among green experiential quality, green equity, green image, green experiential satisfaction and green switching intention. A multi-dimensional model is used as a framework to synthesize the effects of green experiential quality, green equity, green image and green satisfaction on green switching intention of green hotel customers. Design/methodology/approach The data used in this study were collected from a sample of 535 customers staying in one green hotel of Taipei City, Taiwan. Data were analyzed using structural equation modeling and hierarchical regression analysis. Findings The findings support a multi-dimensional model consisting of four dimensions (interaction quality, physical environment quality, access quality and administration quality) to conceptualize and measure perceived green experiential quality. Perceived green experiential quality significantly influences green equity and green image, which, in turn, result in green experiential satisfaction. Green switching intention is influenced by green experiential satisfaction and green image. However, outcome quality is not a component of perceived green experiential quality, which, in turn, insignificantly results in green experiential satisfaction. Green image plays a role in moderating the relationship between green experiential quality and interaction quality, outcome quality, access quality and administration quality. Practical implications To increase green experiential quality and green equity, enhance green image and green experiential satisfaction and decrease green switching intention, the finding of this study will help green hotel management to develop and implement market-oriented service strategies. Originality/value This is the first study to synthesize the effects of green experiential quality, green equity, green image and green experiential satisfaction on green switching intention in a green hotel setting.

The Atacama Large Millimeter/submillimeter Array Survey of Orion Planck Galactic Cold Clumps (ALMASOP) reveals complex nested morphological and kinematic features of molecular outflows through the CO (J = 2−1) and SiO (J = 5−4) emission. We characterize the jet and outflow kinematics of the ALMASOP sample in four representative sources (HOPS 10, 315, 358, and G203.21-11.20W2) through channel maps and position–velocity diagrams (PVDs) parallel and transverse to the outflow axes. The combined CO and SiO emission exhibits the coexistence of the conventional extremely high-velocity jets and shell-like low-velocity cavity walls and new features. More complex, nested bubble-like and filamentary structures in the images and channel maps, triangle-shaped regions near the base of the parallel PVDs, and regions composed of rhombus/oval shapes in the transverse PVDs are also evident. Such features find natural explanations within the bubble structure of the unified model of jet, wind, and ambient medium. The reverse shock cavity is revealed on the PVD base regions, and other features naturally arise within the dynamic postshock region of magnetic interaction. The finer nested shells observed within the compressed wind region reveal previously unnoticed shocked emission between the jet and the conventional large cavity walls. These pseudopulse-produced filamentary features connect to the jetlike knotty blobs, creating an impression of episodicity in mass ejection. SiO emission is enhanced downstream of the reverse shock boundary, with jetlike excitation conditions. Combined, these observed features reveal the extended structures induced by the magnetic interplay between a jet-bearing magnetized wide-angle wind and its ambient magnetized surrounding medium.

Purpose The purpose of this study is to examine the structural relationships between the dimensions of virtual reality (VR) experiences (immersion, interaction, usability and illusion), the dimensions of VR attachment (VR dependence, VR identity, VR affect and VR familiarity) and the dimensions of VR experiential outcomes (VR experiential satisfaction, VR experiential loyalty and VR experiential advocacy). Design/methodology/approach A total of 490 visitors who tried 360 VR travel video games in the TripMoment VR were surveyed. Findings In this study, there are positive relationships between VR experiential satisfaction and immersion, interaction, illusion, as well as VR identity, VR affect and VR familiarity. In addition, VR experiential satisfaction has a positive relationship with VR experiential loyalty. In addition, VR experiential advocacy has a positive relationship with both VR experiential satisfaction and VR experiential loyalty. Practical implications The results show that tourism operators should focus on increasing VR experiential satisfaction and experiential loyalty to enable visitors to have intentions to advocate their VR experiences. Originality/value This paper provides the data that lead to a better understanding of the relationship between the dimensions of VR experiences, VR attachment and VR experiential outcomes in the tourism industry. 旅游中的虚拟实境体验、依附和体验结果 目的 本研究目的是在检验虚拟实境体验维度(沉浸、交互作用、可用性与幻觉),虚拟实境依附维度(虚拟实境依赖、虚拟实境认同、虚拟实境影响与虚拟实境熟悉度)和虚拟实境体验结果维度 (虚拟实境体验满意度、虚拟实境体验忠诚度与虚拟实境体验主张)之间的结构关系。 设计/方法学/方法 在时刻旅行中, 共受访490名游客尝试了360度虚拟实境旅游视频游戏。发现 – 在本次研究中, 虚拟实境体验满意度与沉浸、交互作用、幻觉与虚拟实境认同、虚拟实境影响与和虚拟实境熟悉度均存在正向关系。而且, 虚拟实境体验满意度对虚拟实境体验忠诚度有正向影响。此外, 虚拟实境体验主张对虚拟实境体验满意度与虚拟实境体验忠诚度两者均有正向影响。 实际意涵 结果显示, 为了能使游客有意愿宣传自己的虚拟实境体验, 旅游经营者应该将焦点放在提升虚拟实境体验满意度与虚拟实境体验忠诚度。 原创/价值 本文提供的数据有助于更好地理解旅游行业虚拟实境体验, 虚拟实境依附与虚拟实境体验结果维度之间的关系 Experiencias de realidad virtual, apego y resultados experimentales en turismo Propósito El objetivo de este estudio es examinar las relaciones estructurales entre las dimensiones que afectan a la VR: las experiencias (inmersión, interacción, usabilidad e ilusión), las dimensiones del apego (dependencia de VR, identidad de VR, afecto de VR y familiaridad de VR) y las dimensiones de los resultados experimentales (satisfacción experiencial de realidad virtual, lealtad experiencial de realidad virtual y defensa experiencial de realidad virtual). Diseño/metodología/enfoque Se encuestó a un total de 490 visitantes, que probaron los videojuegos de viaje de 360 VR en TripMoment VR. Resultados En este estudio, demuestra la existencia de relaciones positivas entre la satisfacción experimental de la realidad virtual y la inmersión, la interacción, la ilusión, así como la identidad de la realidad virtual, el efecto de la realidad virtual y la familiaridad de la realidad virtual. Además, la satisfacción experiencial, tiene una relación positiva con la lealtad experiencial, en la realidad virtual. Además, la defensa de la experiencia de VR tiene una relación positiva tanto con la satisfacción de la experiencia de VR como con la lealtad de la experiencia de VR. Implicaciones prácticas Los resultados muestran que los operadores turísticos deberían centrarse en aumentar la satisfacción y la lealtad experiencial de la realidad virtual, para permitir que los visitantes tengan intenciones de defender sus experiencias en los contextos de la misma. Originalidad/valor Este trabajo proporciona datos, que conducen a una mejor comprensión de la relación entre las dimensiones de las experiencias de realidad virtual, el apego a la realidad virtual y los resultados experimentales en la industria del turismo.

Therapies for chronic hepatitis delta virus (HDV) infection are unsatisfactory. Prenylation is essential for HDV and inhibition abrogates HDV production in experimental models. In a proof-of-concept study, we aimed to assess the effect on HDV RNA levels, safety, and tolerability of the prenylation inhibitor lonafarnib in patients with chronic delta hepatitis. In this phase 2A double-blind, randomised, placebo-controlled study, patients aged 18 years or older with chronic HDV infection were randomly assigned (3:1 in group 1 and 2:1 in group 2) to receive lonafarnib 100 mg (group 1) or lonafarnib 200 mg (group 2) twice daily for 28 days with 6 months' follow-up. Participants were randomised by random-number tables blocked in groups of four without stratification. Both groups enrolled six treatment participants and two placebo participants. Group 1 placebo patients received open-label lonafarnib as group 2 participants. The primary therapeutic endpoint was a decrease in HDV RNA viral titre in serum and the primary safety endpoint was the ability to tolerate the drug at the prescribed dose for the full 4-week duration, defined as drug discontinuation due to intolerance or grade 3/4 adverse events. This trial is registered with ClinicalTrials.gov, number NCT01495585. Between Jan 19, 2012, and April 28, 2014, 14 patients were enrolled, of whom eight were assigned to group 1 and six were assigned to group 2. At day 28, compared with placebo, mean log HDV RNA declines from baseline were −0·73 log IU/mL in group 1 (95% CI 0·17–1·31; p=0·03) and −1·54 log IU/mL in group 2 (1·21–1·93; p<0·0001). Lonafarnib serum concentrations correlated with HDV RNA change (r2=0·78, p<0·0001). Model fits show that hepatitis B surface antigen (HBsAg) remained stable after a short pharmacological delay (0·75 days [SE 0·24]), lonafarnib effectiveness in blocking HDV production was greater in group 2 than in group 1 (0·952 [SE 0·06] vs 0·739 [0·05], p<0·001), and the HDV half-life was 1·62 days (0·07). There was no evidence of virological resistance. Adverse events were mainly mild to moderate with group 1 patients experiencing diarrhoea in three patients (50%) and nausea in two patients (33%) and in group 2 with all patients (100%) experiencing nausea, diarrhoea, abdominal bloating, and weight loss greater than 2 kg (mean of 4 kg). No treatment discontinuations occurred in any treatment groups. Treatment of chronic HDV with lonafarnib significantly reduces virus levels. The decline in virus levels significantly correlated with serum drug levels, providing further evidence for the efficacy of prenylation inhibition in chronic HDV. National Institute of Diabetes and Digestive and Kidney Diseases and National Cancer Institute, National Institutes of Health, and Eiger Biopharmaceuticals Inc.