Phase fluctuations-induced bit error ratio of deep-space optical communication systems during superior solar conjunction.

Deep-space optical communication has garnered increasing attention for its high data transfer rate, wide bandwidth, and high transmission speed. However, coronal plasma turbulence severely degrades optical signals during superior solar conjunction. In this study, we introduce the models for plasma density and generalized non-Kolmogorov turbulence power spectrum. Based on these models, we derive the variance of the phase fluctuations with the assistance of the Rytov theory in the weak turbulence regime involving various variables, such as turbulence outer scale, spectral index, relative fluctuation factor, and wavelength. Subsequently, we evaluate the bit error ratio (BER) performance of the deep-space optical communication system, considering phase fluctuations and intensity scintillations, under binary phase shift keying modulation. Numerical calculations reveal that small heliocentric distance, large relative fluctuation factor and spectral index, could induce severe phase fluctuations and high BER. Fortunately, the effects of the plasma irregularities on the BER performance can be mitigated by short optical wavelength under large outer scale.

Experimental Demonstration of a Tunable Energy-Selective Gamma-Ray Imaging System Based on Recoil Electrons.

The domain of gamma-ray imaging necessitates technological advancements to surmount the challenge of energy-selective imaging. Conventional systems are constrained in their dynamic focus on specific energy ranges, a capability imperative for differentiating gamma-ray emissions from diverse sources. This investigation introduces an innovative imaging system predicated on the detection of recoil electrons, addressing the demand for adjustable energy selectivity. Our methodology encompasses the design of a gamma-ray imaging system that leverages recoil electron detection to execute energy-selective imaging. The system's efficacy was investigated experimentally, with emphasis on the adaptability of the energy selection window. The experimental outcomes underscore the system's adeptness at modulating the energy selection window, adeptly discriminating gamma rays across a stipulated energy spectrum. The results corroborate the system's adaptability, with an adjustable energy resolution that coincides with theoretical projections and satisfies the established criteria. This study affirms the viability and merits of utilizing recoil electrons for tunable energy-selective gamma-ray imaging. The system's conceptualization and empirical validation represent a notable progress in gamma-ray imaging technology, with prospective applications extending from medical imaging to astrophysics. This research sets a solid foundation for subsequent inquiries and advancements in this domain.

Effect of N-oleoyl dopamine on myofibroblast trans-differentiation of retinal pigment epithelial cells.

Retinal pigment epithelial (RPE) cells contribute to several clinical conditions resulting in retinal fibrotic scars. Myofibroblast trans-differentiation of RPE cells is a critical step in the process of retinal fibrosis. In this study, we investigated the effects of N-oleoyl dopamine (OLDA), a newer endocannabinoid with a structure distinct from classic endocannabinoids, on TGF-ß2-induced myofibroblast trans-differentiation of porcine RPE cells. Using an in vitro collagen matrix contraction assay, OLDA was found to inhibit TGF-ß2 induced contraction of collagen matrices by porcine RPE cells. This effect was concentration-dependent, with significant inhibition of contraction observed at 3 µM and 10 µM. OLDA did not affect the proliferation of porcine RPE cells. Immunocytochemistry showed that at 3 µM, OLDA decreased incorporation of α-SMA in the stress fibers of TGF-ß2-treated RPE cells. In addition, western blot analysis showed that 3 µM OLDA significantly downregulated TGF-ß2-induced α-SMA protein expression. Taken together these results demonstrate that OLDA inhibits TGF-ß induced myofibroblast trans-differentiation of RPE cells. It has been established that classic endocannabinoid such as anandamide, by activating the CB1 cannabinoid receptor, promote fibrosis in multiple organ systems. In contrast, this study demonstrates that OLDA, an endocannabinoid with a chemical structure distinct from classic endocannabinoids, inhibits myofibroblast trans-differentiation, an important step in fibrosis. Unlike classic endocannabinoids, OLDA has weak affinity for the CB1 receptor. Instead, OLDA acts on non-classic cannabinoid receptors such as GPR119, GPR6, and TRPV1. Therefore, our study indicates that the newer endocannabinoid OLDA and its non-classic cannabinoid receptors could potentially be novel therapeutic targets for treating ocular diseases involving retinal fibrosis and fibrotic pathologies in other organ systems.

Elucidation of the relationship between evodiamine-induced liver injury and CYP3A4-mediated metabolic activation by UPLC-MS/MS analysis.

Evodiamine (EVD), which has been reported to cause liver damage, is the main constituent of Evodia rutaecarpa (Juss.) Benth and may be bioactivated into reactive metabolites mediated by cytochrome P450. However, the relationships between bioactivation and EVD-induced hepatotoxicity remain unknown. In this study, comprehensive hepatotoxicity evaluation was explored, which demonstrated that EVD caused hepatotoxicity in both time- and dose-dependent manners in mice. By application of UPLC-Q/TOF-MS/MS, two GSH conjugates (GM1 and GM2) derived from reactive metabolites of EVD were identified, in microsomal incubation systems exposed to EVD with glutathione (GSH) as trapping agents. CYP3A4 was proved to be the main metabolic enzyme. Correspondingly, the N-acetyl-L-cysteine conjugate derived from the degradation of GM2 was detected in the urine of mice after exposure to EVD. For the first time, the iminoquinone intermediate was found in EVD-pretreated rat bile by the high-resolution MS platform. Pretreatment with ketoconazole protected the animals from hepatotoxicity, decreased the protein expression of cleaved caspase-1 and -3, but increased the area under the serum-concentration-time curve of EVD in blood determined by UPLC-QQQ-MS/MS. Depletion of GSH by buthionine sulfoximine exacerbated EVD-induced hepatotoxicity. These results implicated that the CYP3A4-mediated metabolic activation was responsible for the observed hepatotoxicity induced by EVD.

Average symbol error probability and channel capacity of the underwater wireless optical communication systems over oceanic turbulence with pointing error impairments.

The influence of oceanic turbulence and pointing error impairments on the underwater wireless optical communication (UWOC) systems is considered in this study. We propose a generalized fading model, which comprises the path loss due to the absorption and scattering, the oceanic turbulence (modeled by Málaga distribution), and the pointing error impairments resulting from ocean movements. Thereafter, closed-form expressions of the average symbol error probability (SEP) and average channel capacity are proposed for optical waves propagate in oceanic turbulence with the M-ary pulse position modulation (PPM) and under the constraints of the limited average-power and peak-power. The Monte Carlo simulations are conducted to validate the analytical results and demonstrate that the fading parameters, including the mean-squared temperature, the salinity-temperature contribution factor, jitters, and water conditions, significantly affect the system performance. Moreover, the thermal noise and quantum noise in ocean environment have more serious impact than the background noise. Finally, we prove that the UWOC systems with the pure peak-power constraint performs better than that limited by average-power and peak-power.

Scintillation index for the optical wave in the vertical oceanic link with anisotropic tilt angle.

The influence of the ocean depth and anisotropic tilt angle on vertical underwater wireless optical communication (UWOC) systems is considered in this study. We propose a power spectrum model of oceanic turbulence with an anisotropic tilt angle for the first time. Thereafter, the expression of the scintillation index is derived for a spherical wave propagating over anisotropic oceanic turbulence in the vertical link. In addition, considering the temperature and salinity, relevant data of the Atlantic and Pacific oceans at different depths are selected to study further the effect of ocean depth on the scintillation index. The results indicate that the scintillation index strongly depends on the ocean depth and anisotropic tilt angle. Moreover, the scintillation index is also related to other parameters, such as temperature and salinity, kinematic viscosity, the anisotropic factor, optical wavelength, and propagation distance. The presented results can be beneficial in designing optical wireless communication systems in the ocean environment.

Comparison of open reduction and fixation with hook plate and modified closed reduction and fixation with tightrope loop plate for treatment of rockwood type III acromioclavicular joint dislocation.

OBJECTIVE: To compare the outcomes of open reduction and hook plate fixation (ORHPF) and modified TightRope loop plate fixation (MTRLPF) in the treatment of Rockwood type III acromioclavicular joint dislocation. METHODS: This was a retrospective study. Data on 71 patients with Rockwood type III acromioclavicular joint dislocation who underwent either ORHPF (n = 39) or MTRLPF (n = 32) between January 2016 and October 2019 were extracted and analyzed. Baseline data at injury were compared to evaluate the balance. The disabilities of the arm, shoulder, and hand (DASH) score, Constant-Murley score and visual analog scores (VAS) score at 1 month, 3 months, 6 months and 12 months after operation were compared; further, at 12 months coracoclavicular distance and related complications were evaluated and compared. RESULTS: Both groups did not differ for any baseline data. At 1 and 3 months after operation, MTRLPF group exhibited a significantly better performance than the ORHPF group in VAS (1 month: 2.4 ± 1.8 vs 3.0 ± 1.7; 3 months: 1.2 ± 1.4 vs 1.8 ± 1.6), Constant-Murley (1 month: 75.2 ± 11.2 vs 63.8 ± 13.7; 3 months: 81.4 ± 9.8 vs 75.8 ± 10.6), DASH (1 month: 33.6 ± 6.8 vs 40.6 ± 6.1; 3 months: 21.2 ± 7.4 vs 25.6 ± 6.6). At 6 months, only Constant-Murley remained marginally significant (p = 0.048). At 12 months, no statistical difference was observed for any outcome variable (all P > 0.05 for VAS, Constant-Murley and DASH), coracoclavicular distance (12.7 ± 1.6 mm vs 12.2 ± 1.6 mm; P = 0.374), or overall complication rate (P = 0.763). CONCLUSIONS: For Rockwood type III acromioclavicular joint dislocation, both methods can achieve satisfactory 1-year results, but modified minimally invasive TightRope treatment is more advantageous in early functional recovery at 1 and 3-month follow-ups.

Cannabidiol Signaling in the Eye and Its Potential as an Ocular Therapeutic Agent.

Cannabidiol (CBD), the major non-intoxicating constituent of Cannabis sativa, has gained recent attention due to its putative therapeutic uses for a wide variety of diseases. CBD was discovered in the 1940s and its structure fully characterized in the 1960s. However, for many years most research efforts related to cannabis derived chemicals have focused on D9-tetrahydrocannabinol (THC). In contrast to THC, the lack of intoxicating psychoactivity associated with CBD highlights the potential of this cannabinoid for clinical drug development. This review details in vitro and in vivo studies of CBD related to the eye, the therapeutic potential of cannabidiol for various ocular conditions, and molecular targets and mechanisms for CBD-induced ocular effects. In addition, challenges of CBD applications for clinical ocular therapeutics and future directions are discussed.

Benzannulated 5,5-spiroketal sesquiterpenes from the roots of Angelica Pubescens.

Two new tetrahydrobenzannulated 5,5-spiroketal sesquiterpenes (1 and 2) and three novel benzannulated 5,5-spiroketal sesquiterpenes (3-5) namely angepubesins A-E, together with a new heliannane-type benzannulated sesquiterpene namely angepubesin F (6) and two known monoterpenes (7 and 8), were isolated from the roots of Angelica Pubescens. Their structures were identified by various spectroscopic analyses (NMR, MS, UV, IR), in combination with 13C NMR calculation as well as MAE, CMAE, DP4 + and MAEΔΔδ values analyses. The absolute configurations of 1-6 were determined by modified Mosher's method, ECD calculation and single-crystal X-ray diffraction (Cu Kα). Furthermore, the inhibitory activities of these isolated compounds against nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophage cells were evaluated. The results showed that compounds 2-4, 6 and 7, especially 6, displayed markedly inhibitory effects on NO production in a concentration-dependent manner. Mechanical study revealed that compound 6 could significantly inhibit the expression of nitric oxide synthase (iNOS) protein at a concentration of 10 µM. In addition, compound 6 suppressed the activation of JAK-STAT and NF-κB pathways.

Preoperative deep venous thrombosis (DVT) after femoral neck fracture in the elderly, the incidence, timing, location and related risk factors.

OBJECTIVE: To investigate the epidemiologic characteristics of deep venous thrombosis (DVT) in elderly patients with femoral neck fracture. METHODS: Retrospective analysis was performed on elderly patients with femoral neck fractures admitted to two institutions from January 2016 to October 2019. Duplex ultrasonography (DUS) was used to detect DVT. Patients' hospitalization medical records were retrieved to collect the data, which were related to demographics, comorbidities, injury and laboratory results on admission. Patients with preoperative DVT were defined as the case group and those without DVT as control group, and compared using the univariate analyses. Multivariate logistic regression analysis was used to identify the independent factors associated with DVT. RESULTS: Totally, 980 patients met the predefined criteria and were included. Sixty-seven patients were diagnosed to have preoperative DVT, with incidence of 6.8% for overall, 1.7% for proximal and 5.1% for distal DVT. The mean time from injury to diagnosis of DVT was 6.0 ± 4.7 days (median, 5.0). Most (76.1%) patients with DVT had thrombi solely in the injured extremity, in contrast with 14.9% (10/67) in the uninjured and 9.0% (6/67) in both injured and uninjured extremity. Multivariate analysis showed chronic renal insufficiency (OR, 3.37; 95%CI, 1.57 to 7.28), current smoking status (OR, 2.42; 95%CI, 1.23 to 5.63), time from injury to DUS (OR, 1.26; 95%CI, 1.07 to 1.61) and PLT > 220*109/L (OR, 1.94; 95%CI, 1.31 to 3.77) were independent factors for DVT. CONCLUSION: Preoperative DVT is not very prevalent following elderly femoral neck fractures, but with a certain proportion in the uninjured extremity, necessitating the more attention. These identified risk factors aid in patient counseling, individualized risk assessment and risk stratification, and should be kept in mind.

Discovery of endogenous inverse agonists for G protein-coupled receptor 6.

The orphan G protein-coupled receptor 6 (GPR6) is highly expressed in the striatum and has been linked to multiple striatal pathologies. The identification of endogenous ligands and their mechanisms of action at GPR6 will help to elucidate the physiological and pathological roles of the receptor. In the current study, we tested the concentration-dependent effects of a variety of endocannabinoid-like N-acylamides on GPR6 signaling. Here, we demonstrate for the first time that N-arachidonoyl dopamine, N-docosahexaenoyl dopamine, N-oleoyl dopamine and N-palmitoyl dopamine exert inverse agonism at GPR6. This effect was concentration-dependent, with potencies in the micromolar range, and functionally selective for ß-arrestin2 recruitment. Structure-activity relationship studies demonstrate that both the N-acyl side chain and the dopamine head group are important for these ligands to act on GPR6. Our discovery of these N-acyl dopamines as endogenous inverse agonists for GPR6 moves us one step further in understanding the roles GPR6 play in neurodegenerative and neuropsychiatric disorders related to striatal dysfunction.

Involvement of dopamine receptor in the actions of non-psychoactive phytocannabinoids.

Nematode Caenorhabditis elegans (C. elegans) exhibited a vigorous swimming behavior in liquid medium. Addition of dopamine inhibited the swimming behavior, causing paralysis in 65% of wild-type nematodes. Interestingly, phytocannabinoids cannabidiol (CBD) or cannabidivarin (CBDV), caused paralysis in 40% of the animals. Knockout of DOP-3, the dopamine D2-like receptor critical for locomotor behavior, eliminated the paralysis induced by dopamine, CBD, and CBDV. In contrast, both CBD and CBDV caused paralysis in animals lacking CAT-2, an enzyme necessary for dopamine synthesis. Co-administration of dopamine with either CBD or CBDV caused paralysis similar to that of either phytocannabinoid treatment alone. These data support the notion that CBD and CBDV act as functional partial agonists on dopamine D2-like receptors in vivo. The discovery that dopamine receptor is involved in the actions of phytocannabinoids moves a significant step toward our understanding of the mechanisms for medical uses of cannabis in the treatment of neurological and psychiatric disorders.

Clerodane Diterpenoids Isolated from the Leaves of Casearia graveolens.

A phytochemical survey aiming to acquire pharmacologically active substances has resulted in the isolation of nine new clerodane diterpenoids, named graveospenes A-I (1-9), from the leaves of Casearia graveolens. Spectroscopic methods were employed to establish the structures with their absolute configurations being confirmed by ECD data analysis. A biological evaluation was performed, and compound 1 was found to be cytotoxic to both human lung cancer cells (A549) and human hepatocellular carcinoma cells (HepG2). A mechanism-of-action study on 1 revealed this compound to induce apoptosis of A549 cells and impede them at the G0/G1 stage.

Outage probability and channel capacity of an optical spherical wave propagating through anisotropic weak-to-strong oceanic turbulence with Málaga distribution.

The influence of anisotropic weak-to-strong oceanic turbulence on the performance of underwater optical communication (UWOC) systems is investigated in this paper. The Málaga distribution fading model is used to model the statistical distribution of a spherical wave propagating through anisotropic oceanic turbulence, which is a versatile model of weak-to-strong turbulence. First, the scintillation index for a spherical wave propagating in oceanic turbulence is formulated, and closed-form expressions for the outage probability and average channel capacity of the UWOC systems are then proposed in terms of Meijer's G function. The simulation results demonstrate that both the outage probability and the average channel capacity strongly depend on the parameters of oceanic turbulence, such as the ratio of temperature to the contribution of salinity to the refractive index spectrum, the rate of dissipation of kinetic energy per unit mass of fluid, and the rate of dissipation of mean-squared temperature; they are also related to system parameters such as wavelength and aperture diameter. Numerical results are provided to verify the accuracy of our proposed expressions for outage probability and average channel capacity, and perfect agreement is observed.

Mandibular osteotomy-induced hypoxia enhances osteoclast activation and acid secretion by increasing glycolysis.

The rapid bone remodeling after osteotomy has been reported for a long time. However, the underlying mechanism promoting the active bone reconstruction was still to be elucidated. Since not only the bone, blood vessels, and supportive tissues, but also the local microenvironment were destroyed, if the changes on the cell metabolism was contributed to the accelerated bone remodeling came into sight. In present study, we found that the mandibular osteotomy in rabbit activated osteoclasts, as well as the expression of hypoxia-inducible factor 1α (HIF-1α) in alveolar bone. Hypoxia or HIF-1α could enhanced osteoclastogenesis, bone absorption, and lactic acid concentration in receptor activator of nuclear factor κΒ ligand-induced RAW264.7 cells. Coincided with the upregulated HIF-1α expression, HIF-driven glycolytic enzymes, such as lactate dehydrogenase A (LDHA), glucokinase (GCK), pyruvate kinase M2 (PKM2), and phosphofructokinase1 (PFK1), were found massively increased in both hypoxic RAW264.7 cells and the alveolar HIF-1α-positive osteoclasts after mandibular osteotomy. Knockdown of HIF-1α suppressed not only the hypoxia-mediated glycolysis, but also the hypoxia-induced acid secretion and bone resorption in RAW264.7 cells. Application of inhibitor on glycolysis gave rise to the similar results as HIF-1α knockdown. Our findings suggested that hypoxia-driven glycolysis in osteoclasts was an adaptive mechanism to permit alveolar bone remodeling after mandibular osteotomy.

Bioactive Diterpenoids from the Stems of Euphorbia antiquorum.

A total of 18 diterpenoids, including 10 new analogues (1-10), were isolated from Euphorbia antiquorum. The structures were characterized by spectroscopic techniques, and circular dichroism data analysis was adopted to confirm the absolute configurations of 1-10. Compounds 1-9 were classified as ent-atisane diterpenoids, and 10 was assigned as an ent-kaurane diterpenoid. The biological evaluation of nitric oxide (NO) production inhibition was conducted, and all of these isolates showed the property of inhibiting NO generation in lipopolysaccharide-induced BV-2 cells. Further research on molecular docking disclosed the affinities between the diterpenoids obtained and inducible nitric oxide synthase.

GPR3, GPR6, and GPR12 as novel molecular targets: their biological functions and interaction with cannabidiol.

The G protein-coupled receptors 3, 6, and 12 (GPR3, GPR6, and GPR12) comprise a family of closely related orphan receptors with no confirmed endogenous ligands. These receptors are constitutively active and capable of signaling through G protein-mediated and non-G protein-mediated mechanisms. These orphan receptors have previously been reported to play important roles in many normal physiological functions and to be involved in a variety of pathological conditions. Although they are orphans, GPR3, GPR6, and GPR12 are phylogenetically most closely related to the cannabinoid receptors. Using ß-arrestin2 recruitment and cAMP accumulation assays, we recently found that the nonpsychoactive phytocannabinoid cannabidiol (CBD) is an inverse agonist for GPR3, GPR6, and GPR12. This discovery highlights these orphan receptors as potential new molecular targets for CBD, provides novel mechanisms of action, and suggests new therapeutic uses of CBD for illnesses such as Alzheimer's disease, Parkinson's disease, cancer, and infertility. Furthermore, identification of CBD as a new inverse agonist for GPR3, GPR6, and GPR12 provides the initial chemical scaffolds upon which potent and efficacious agents acting on these receptors can be developed, with the goal of developing chemical tools for studying these orphan receptors and ultimately new therapeutic agents.

Amplitude fluctuations for optical waves propagation through non-Kolmogorov coronal solar wind turbulence channels.

Optical communication has a great potential for the future deep space communication, while the amplitude fluctuations caused by the coronal solar wind irregularities has been a challenging topic during superior solar conjunction. In this paper, a closed-form amplitude fluctuations expression for optical waves propagation through non-Kolmogorov solar wind turbulence is derived by establishing a generalized coronal turbulence spectrum model. The profound impact of the coronal parameters on the bit error rate (BER) performance of the free space optical system is also investigated based on the derived amplitude fluctuations model. The derived expression allows easy analysis of the evolution of the amplitude fluctuations and, in particular, an understanding of the imposed effects caused by the parameters during the waves propagation. The combined effect of the optical wavelength, non-Kolmogorov spectral index, turbulence outer scale, relative solar wind density fluctuation factor, and link distance on amplitude fluctuations are evaluated. Numerical calculations show that these parameters produce obvious effects on the amplitude fluctuations and the BER. The large optical wavelength can mitigate the influence of the coronal turbulence. Our results have potential applications for evaluating the link performance of the future deep space communication.

A novel method of using elastic bionic fixation device for distal tibiofibular syndesmosis injury.

PURPOSE: To describe and evaluate the novel method of using elastic bionic fixation device in treating the distal tibiofibular syndesmosis (DTS) injury. METHODS: From June 2013 to January 2014, 17 subjects with ankle fractures combined with DTS separation were treated by the elastic bionic fixation device. The syndesmotic parameters, healing, functional scores, and possible complications were recorded. RESULTS: All patients had a mean follow-up of 23.35 ± 4.39 months (range, 15-28 months). Syndesmotic parameters returned to normal after surgery and remained normal throughout the follow-up period. X-ray examinations at 12 months follow-up showed no cable breakage of the elastic bionic fixation device or instrument invalidation compared to that of immediate post-operative X-ray films. Besides, no signs of articular degeneration and arthritis were observed. Furthermore, change in bone density near the fibular fixing button or tibial screw nut was also not detected. Primary wound healing was observed in 16 patients, while the remaining one showed redness and swelling of lateral ankle incision and got wound healing after seven to ten  days of antibiotic therapy and local radio frequency physiotherapy. All obtained excellent and good outcomes according to the AOFAS score at 12 months after surgery. CONCLUSIONS: The use of elastic bionic fixation device appears to be a promising option in treating DTS injury because it can provide stable and reliable elastic fixation, good functional recovery, and relatively fewer complications.

GPR3 and GPR6, novel molecular targets for cannabidiol.

GPR3 and GPR6 are members of a family of constitutively active, Gs protein-coupled receptors. Previously, it has been reported that GPR3 is involved in Alzheimer's disease whereas GPR6 plays potential roles in Parkinson's disease. GPR3 and GPR6 are considered orphan receptors because there are no confirmed endogenous agonists for them. However, GPR3 and GPR6 are phylogenetically related to the cannabinoid receptors. In this study, the activities of endocannabinoids and phytocannabinoids were tested on GPR3 and GPR6 using a ß-arrestin2 recruitment assay. Among the variety of cannabinoids tested, cannabidiol (CBD), the major non-psychoactive component of marijuana, significantly reduced ß-arrestin2 recruitment to both GPR3 and GPR6. In addition, the inhibitory effects of CBD on ß-arrestin2 recruitment were concentration-dependent for both GPR3 and GPR6, with a higher potency for GPR6. These data show that CBD acts as an inverse agonist at both GPR3 and GPR6 receptors. These results demonstrate for the first time that both GPR3 and GPR6 are novel molecular targets for CBD. Our discovery that CBD acts as a novel inverse agonist on both GPR3 and GPR6 indicates that some of the potential therapeutic effects of CBD (e.g. treatment of Alzheimer's disease and Parkinson's disease) may be mediated through these important receptors.