Low Magnitude Research Articles

ETS-NOCV description of chemical bonding: from covalent bonds to non-covalent interactions

ContextThe interpretation of ETS-NOCV for typical covalent and dative-covalent chemical bonds is presented and compared with that for halogen bonds. Possible tuning of the strength of halogen bonding is considered, first by applying an electric field (modeled by the point charges or the electric field vector), and then by constructing a model transition-metal complex with enhanced strength of halogen bonding. For all the systems, the ETS-NOCV picture is supplemented by the analysis of the deformation in molecular electrostatic potential (ΔMEP). The results demonstrate important characteristic features of the analysis based on NOCV: (i) this approach is based on pairs of orbitals with antibonding and bonding character and, thus, allows us to “extract” the “diatomic-like” picture of chemical bonding; (ii) the NOCV-pair contributions to the deformation density often correspond to donation (AB) and back-donation (AB) of electron density between the fragments. The results for halogen bonding demonstrate that it is possible to tune their strength by an electric field in the molecular environment; the halogen-bond energy can reach the order of magnitude typical of dative-covalent bonds. However, the nature of halogen bonds still differs from that of dative-covalent interactions, as the accumulation of electron density between fragments is of significantly lower magnitude. The main effect of the electric field is an increase in the polarization of the fragments, which is clearly manifested by the deformation in the MEP.MethodsAll calculations were performed using the ADF/AMS package. The BLYP exchange–correlation functional was employed with Grimme’s dispersion correction (D3 version) and Becke-Johnson damping, using TZP basis sets. The deformation in the MEP was determined as ΔVr=VABr-VAr-VBr, with the same fragment definition as in the ETS-NOCV method.

Complex precursory activity prior to the c.7600 yr BP Mazama (Crater Lake, USA) eruption

Large magnitude explosive volcanic eruptions occur globally at a rate of 1–2 per 1000 years and can cause devastating global impacts. Despite the risk these eruptions pose, we have no reliable method to forecast whether lower magnitude eruptions are precursory to a larger event. Here we ask whether we can identify unique precursors to a large eruption using data from the runup to the ~7.6 ka eruption of Mount Mazama (Crater Lake, Oregon). We present new compositional and textural data that suggest the precursory sequence involved at least three distinct eruptions. In this way, the climactic Mazama eruptive sequence resembles the four-month build-up to the 1883 Krakatau eruption. We highlight the distinct properties of the lowermost unit that suggests at least one precursory eruption tapped a distinct magma reservoir supporting the idea that to evacuate large magma volumes you require the pre- or syn-eruptive amalgamation of multiple melt lenses.

Baseline-dependent improvement in CF studies, plausibility of bias

Background:It has been commonly reported that therapeutic treatments in cystic fibrosis (CF) have ceiling effects, such that their efficacy is diminished for persons with high pre-treatment health (Montgomery et al., 2012 and Newsome et al., 2019). Floor effects have also been reported where decline is of lower magnitude in those with below-average pre-treatment health (Harun et al., 2016; Konstan et al., 2012 and Szczesniak et al., 2017). When measurement error is present, the statistical literature has warned of exaggerated or spurious associations between pre-treatment measures and subsequent change (Chambless and Davis, 2003 and Yanez et al., 1998). Measurement error, equivalently described as day-to-day variation, has been described to occur in CF outcome measurements such as forced expiratory volume in 1 s taken by spirometry (FEV1pp) (Magaret et al., 2024; Stanojevic et al., 2020 and Thornton et al., 2023). Methods:We conducted a simulation study to assess the potential for spurious floor or ceiling effects in studies of CF therapeutics. We considered uncontrolled or single-arm studies, and evaluated estimated association between pre-treatment FEV1pp and treatment-induced change: post- versus pre-treatment. Results:When day-to-day variation was present in FEV1pp, at levels equivalent to those reported in large studies measuring spirometry both at home and in clinic, naive analytic approaches found spurious associations of change with baseline (Paynter et al., 2022 and Saiman et al., 2003). Type I error ranged from 31.9% to 98.3% for day-to-day variation as high as 3% to 15% relative to biological variation. Incorporating known day-to-day variation, the regression calibration approach corrected bias and controlled type I error (Chambless and Davis, 2003). Conclusion:Exaggerated ceiling effects are possible. Further studies could provide meaningful confirmation of ceiling effects in CF, perhaps reducing day-to-day variation by incorporating multiple pre- and post-treatment measurements.

Psychometric evidence of the adaptation to the Brazilian context of the Childhood Mania Rating Scale - Parent/Guardian Version (CMRS-P).

To carry out the process of cross-cultural adaptation of the Child Mania Rating Scale - Parent Version (CMRS-P) for the Brazilian context. Statistical procedures were carried out, based on the analysis of the validity of the internal structure of the scale, as well as its relationship with external variables. 224 parents/guardians of children/adolescents aged between five and 18 years participated in the study. The data collection form included instruments for assessing (hypo)manic symptoms, irritability, inattention, hyperactivity, emotional symptoms and behavioral problems. Data were collected in person, at a public school and at a Psychosocial Care Center, and online (via Google forms). Exploratory and confirmatory factor analyses, measurement invariance analyses, reliability analyzes were performed, as well as convergent and concurrent validity analyses. The one-dimensional model was investigated, showing satisfactory results, similar to those of the original scale. A reduced version was proposed with the ten most robust items from this study. Validity analyzes based on hypotheses indicated higher scores among those subjects with more clinical problems, such as the previous existence of a psychiatric diagnosis. Statistically significant and positive correlations, of low and moderate magnitudes, were observed with the scores of the other instruments used. The results indicated that the adapted versions of the CMRS-P (full scale and reduced form) are promising instruments for use in the country.

Deep neural network-assisted fast and precise simulations of electrolyte flows in redox flow batteries

Flow fields are a key component in redox flow batteries, which is to distribute electrolytes onto electrodes at the maximum uniformity with the minimum pump work. Achieving this design goal requires accurate simulations of electrolyte flows and identification of the dead zones where the flows become weak or stagnant. However, conventional case-by-case numerical simulation requires significant computational resources. In this work, we use deep learning to predict the electrolyte flow in flow batteries with a neural network knows as U-Net. The U-Net is well trained by learning the mapping between the input (flow field geometry) and output (velocity magnitude distribution). Results show that the pixel-wise comparison of the velocity magnitudes between the U-Net-predicted results and finite element simulated results exhibits an average Euclidean distance of 442.6 and an average R2 of 0.979, indicating that the electrolyte distribution can be accurately simulated based on the geometric characteristics of flow fields. In addition, dead zones are precisely identified by labeling the regions with low velocity magnitudes. Modifying the channel depth in these regions substantially enhances the under-rib convection, thereby improving the system efficiency by 5.5 % at 200 mA cm−2. Furthermore, compared to the numerical simulation, the U-Net-assisted prediction significantly reduces the computational time by 99.9 %. It is anticipated that the U-Net-assisted simulation provides an accurate and efficient tool for obtaining the velocity distribution of flow fields that can assist the flow field design especially in large quantities and large scale.

Former Executives as Supervisors: Conflicts of Interest and Accounting Discretion

Due to their information advantages, former executives are routinely appointed to supervisory roles within the same firm. This practice of transitioning is often criticized based on concerns about former executives’ lack of independence and potential conflicts of interest. As supervisors, one of their main tasks is to oversee the financial reporting process and to challenge management’s assumptions and the projections that shape reporting outcomes. This study examines the effects of transitioning managers on accounting discretion in the context of goodwill impairments. Based on a hand-collected sample of such transition events, we find a decreased propensity and lower magnitude of goodwill impairments following transitions. This effect is robust when controlling for the underlying economic situation of the firms. Further analyses reveal that the effect is muted for transitions of more experienced executives, for transitions into more independent boards, and for transitions after longer cooling-off periods. Overall, our findings suggest that former executives who become supervisors tend to impact the way accounting discretion is exercised. Thereby, we add to the assessment of an important governance phenomenon and relate to regulatory debates around mandatory cooling-off periods and the impairment-only approach for goodwill accounting.

Genotyping and m-RNA expression analysis of heat shock factor (HSF-1) gene in lactating goat during heat stress

Heat shock factors (HSFs) are essential for cells to respond to thermal stress, activating genes that protect the cells. Different HSFs help cells respond to various environmental and physiological changes. The present study was conducted to assess the impact of thermal stress on goats with different genotypes. The variation in DNA Indian goat breeds and effect of thermal stress on mRNA levels of HSF-1 gene was studied. Genotyping of the HSF-1 gene was performed in four Indian goat breeds using high resolution melting (HRM). Out of the 138 samples, the distribution percentages of different genotypes were 60.87% (AA/blue), 17.39% (AC/red) and 13.04% (CC/green) and 8.70 (AT/Pink). Caprine peripheral blood mononuclear cells (PBMCs) were used to extract total RNA, which was transcribed into cDNA. The relative expression patterns of the HSF1 gene were assessed in Jamunapari goats with differing milk yields under heat stress phenotypes (HST and HSS). Low milk yield goats with the HSS phenotype exhibited a relative expression 0.7072-fold change, while those with the HST phenotype showed 0.7846- fold change. High milk yield goats with the HSS phenotype demonstrated 0.4928, and those with the HST phenotype exhibited 0.3694. However, the expression pattern of the HSF1 gene did not differ statistically between the groups. The regulation of the HSF1 gene may be attributed to the lower magnitude of heat stress in this study, which was insufficient to induce a robust cellular stress response in lactating Jamunapari goats. These findings provide insights into the genetic and phenotypic factors influencing heat stress resilience and milk production in Jamunapari goats. Understanding these factors is crucial for developing improved breeding strategies aimed at enhancing heat tolerance and productivity in this breed.

Expectation of analgesia increases the inhibitory response of conditioned pain modulation in healthy participants who at baseline have a non‐inhibitory profile

AbstractBackgroundThis study assessed the effect of expectation of analgesia on conditioned pain modulation (CPM) in healthy participants stratified into inhibitors and non‐inhibitors.MethodsA parallel CPM protocol was assessed on 21 women and 22 men across two sessions: baseline and expectation of analgesia, which was induced by a standardized audiovisual suggestion. The CPM assessment involved two different test stimuli (TS): mechanically controlled palpation and the pressure pain threshold, applied to two different regions: anterior temporalis and thenar eminence of the hand. The conditioning stimulus (CS) involved immersing the non‐dominant forearm in cold water. The order of the TS and regions was randomized for each participant. The CPM protocol was performed three times, with a 1‐min interval between TS/region sequences. After a 20‐min rest, the CPM assessment was repeated (two blocks in total). The standard error of measurement (SEM) was computed to identify inhibitors (inhibitory responses) and non‐inhibitors (including non‐inhibitors and facilitatory responses). Cochran's Q, ANOVA and ANCOVA were applied to the data (p < 0.05).ResultsThere was a significant decrease in the proportion of non‐inhibitors during the expectation of analgesia session (32.6%–44.2%) when compared with the baseline session (51.2%–72.1%). The non‐inhibitors exhibited a lower inhibitory CPM magnitude than the inhibitors only in block 1 of the baseline session. The expectation of analgesia resulted in an increased magnitude of the inhibitory CPM solely in non‐inhibitors.ConclusionExpectation of analgesia can increase the inhibitory response of the CPM beyond the measurement error in healthy participants with a baseline non‐inhibitory profile.SignificanceSeveral studies have investigated whether cognitive modulation can alter the magnitude of the inhibitory response of conditioned pain modulation (CPM), yet some gaps remain. This study accounted for measurement error to accurately determine changes in CPM influenced by expectation of analgesia.

A Special Kind of Interplanetary Coronal Mass Ejections

Abstract It is generally believed that Coronal mass ejections (CMEs) have magnetic flux rope structures because of their helical shapes. However, only about 30-40% of interplanetary CMEs (ICMEs) have a local magnetic flux rope structure. The usually explanations are that the spacecraft only crossed the flank of the ropes and failed to detect the complete magnetic flux rope structure, or some processes destruct these magnetic flux rope structure. Several studies suggest that some ICMEs inherently possess disordered magnetic fields and consequently exhibit no magnetic flux-rope structures. We introduce a special kind of ICMEs. They have low magnetic field magnitude and stable magnetic field direction, relatively fast expansion speed, lower proton temperature and density. Their all three measured magnetic field components are relatively stable. We want to know whether these ICMEs also have magnetic flux rope structures or not. We identified 20 special ICMEs and analyzed their evolution based on their observed characteristics. We took a special ICME as example, which had apparent rope configuration at 1 AU but evolved to a special ICME at 5.4 AU, to illustrated that this kind of ICMEs may come from magnetic clouds (MCs) whose rope structure had been being stretched due to expansion. We inferred that the missing of obvious flux rope structure may be due to the expansion of MCs, not the flank crossing effect. However, more than 50% of the events were associated with dominant x-component of the magnetic filed, which indicates a leg crossing. Therefore, the detection of part of these special ICMEs may also be results of leg crossing effect.

Spatial landscape response to active tectonics along the Western Mae Chan Fault, Northern Thailand

Mae Chan Fault (MCF) is one of the active faults in northern Thailand, Lao PDR, and Myanmar. Despite fault activeness, the records of recent earthquakes show a lower frequency and magnitude of earthquakes across the MCF than those of the surrounding regions. The morphotectonic analysis evaluates relative tectonic activity based on the drainage systems’ adjustment and geomorphic expressions. We analyzed the Western Mae Chan Fault (WMCF) to explore the spatial response of landscape to relative rock uplift and long-term deformation. We delineated fault segment lines from the remote sensing and the topographic expressions from the digital elevation model. We analyzed the topographic variations from 70 low-order channels developed along the WMCF and evaluated the tectonic activity using geomorphic indices, including the hypsometric integral and hypsometric curve, the standardized stream length-gradient index, the elongation ratio, the drainage basin asymmetrical factor, the mountain front sinuosity, and the valley floor width-to-height ratio. Combining these geomorphic factors with field observations provides the relative indices of active tectonics (RIAT). Our findings revealed that lineament detection from the remote sensing technique indicated the ENE-WSW direction of fault segments. The overall tectonic activity is relatively moderate, but high tectonic activity is present along the western terrain and high topography in the east. The various tectonic activities are consistent with the spatial variations in lineament density and differential rock uplift, where the terrain experienced spatial variations in transtensional and transpressional regimes. This study highlights the potential long-term tectonic activity along the WMCF that dominantly sculpts the modern landscape.

Enhancing clay soil reinforcement using MICP-BIN method with biochar-induced nucleation

The microbially induced carbonate precipitation (MICP) method has gained extensive use in the realm of soil stabilisation. This study presents a novel microbial solidification technique known as the biochar-induced nucleation (MICP-BIN) method for reinforcing clay soil. Corn stover biochar was employed as an auxiliary material, mixed with dry clay powder, and subsequently reinforced using the MICP technique. Direct shear tests, drying experiments, X-ray diffraction, and scanning electron microscopy were also conducted to investigate the efficacy of the MICP-BIN method. Compared with that of the remoulded soil, the shear strength of the treated soil exhibited a substantial increase of 22.4%, the CaCO3 content increased by 30%, and the shear strength improved by 389.5%. Similarly, the internal friction angle exhibited increases of 22.7% and 405.2%, while the cohesion showed improvements of 9.4% and 344.3%, respectively. The MICP-BIN method is found to increase suction for a given water content. Furthermore, biochar-amended soil possesses highest water-retention ability (especially at lower suction magnitude), followed by MICP-amended soil, MICP-BIN-amended soil, and untreated soil. This study demonstrated the promising results achieved by combining biochar and the MICP-BIN technique, providing a novel approach for reinforcing soft ground.

Detecting subtle subterranean movement via laser speckle imaging.

A diversity of organisms live within underground environments. However, visualizing subterranean behavior is challenging because of the opacity of most substrates. We demonstrate that laser speckle imaging, a non-invasive technique resolving nanometer-scale movements, facilitates quantifying biological activity in a granular medium. We monitored fire ants (Solenopsis invicta) at different developmental stages, burial depths (1-5 cm) and moisture fractions (0 and 0.1 by volume) in a container of 0.7 mm glass particles. Although the speckle pattern from the backscattered light precludes direct imaging of animal kinematics, analysis of integrated image differences revealed that spiking during ant movement increased with the developmental phase. Greater burial depth and saturation resulted in fewer and lower magnitude spikes. We verified that spiking correlated with movement via quasi-2D experiments. This straightforward method, involving a laser and digital camera, can be applied to laboratory and potentially field situations to gain insight into subterranean organism activities.

Ecological Flow as a Water Stress Control Strategy: San Rodrigo River, Coahuila, Mexico

Ecological flow refers to the minimum amount of water that must be maintained in a body of water to protect and preserve aquatic ecosystems. This article aims to analyze the function of ecological flow to address the reproduction of the natural hydrological regime of the San Rodrigo River, Coahuila, Mexico. A quantitative methodology was used where the ecological flow was determined based on the Mexican Standard NMX-AA-159-SCFI-2012 considering the period from 1962 to 2016. The maximum data allows us to identify runoffs of low magnitude of 6.65–15.60, those with an average trend close to 500 Mm3, and floods of extraordinary volume (namely, those 844–1260 and 1670 Mm3) with a frequency of every 35 years. Likewise, the river marks drastic changes in the flow in certain years, ranging from 0.64 to 1260 Mm3, so that the rate of variation would possibly exceed several orders of magnitude scaled in an annual phase. In conclusion, this calculation indicates that the body of water may have the function of environmental conservation covered throughout the year, with the data suggesting that in the short term the river will recover part of the water that passed through its course and thus avoid its deterioration.

A systematic review of efficacy and safety of newer drugs approved from 2016 to 2023 for the treatment of complicated urinary tract infections

Background: Complicated urinary tract infections are a significant cause of morbidity, hospitalization, and elevated hospital costs associated with kidney transplantations. The treatment of complicated urinary tract infections is very challenging, due to varying severities of infection and lower cure rates. The available drug options for treating these infections are limited, each with different mechanisms of action, efficacy, and safety profiles, making drug selection more difficult for healthcare professionals. Objectives: A systematic review was conducted to evaluate the safety and efficacy of drugs approved by the United States Food and Drug Administration for the treatment of complicated urinary tract infections between 2016 and 2023. The primary endpoint for all drugs used in treating complicated urinary tract infections was the cure rate. Results: Among the drugs used for treating complicated urinary tract infections, meropenem had the highest cure rate at 91.4%, followed by plazomicin at 88% and cefiderocol at 73% when used as monotherapy. In combination therapy, meropenem-vaborbactam had the highest cure rate at 98.4%, followed by piperacillin-tazobactam at 94%, and ceftazidime-avibactam at 87.5%. The safety profiles of the drugs indicated that almost all drugs caused gastrointestinal symptoms, with imipenem-relebactam and colistin-imipenem combinations having the most serious adverse events. Cefiderocol had a low magnitude of adverse events, with most side effects being mild gastrointestinal symptoms. Conclusion: The study concludes that appropriate drug selection and treatment adherence are crucial for preventing complicated urinary tract infections and improving health outcomes.

Abstract 4137359: Electrocardiographic ST–T area assessed by a computerized quantitative method were associated with increased risk of cardiovascular disease, especially ischemic stroke, in patients with cardiovascular risk factor

Background: ST changes in the lateral leads, which reflect ischemic changes, are associated with cardiovascular events. However, quantitative assessment of the ST–T area and its association with cardiovascular events remains unclear. Hypothesis: Electrocardiographic ST–T areas in lateral leads (V5 and V6) quantitatively assessed by machine analysis were associated with cardiovascular events. Methods: We enrolled 4,654 subjects from the Cardiovascular Prognostic Coupling Study in Japan (Coupling Registry), who had one or more cardiovascular risk factors. The primary endpoint was composite (cardiovascular death, myocardial infarction, stroke), and the secondary endpoints were myocardial infarction and stroke. ST–T area was assessed as the area enclosed by the baseline from the end of the QRS complex to the end of the ST–T segment using a computerized quantitative method. We used the lower magnitude of ST–T area in the V5 or V6 lead for the analysis. The endpoints were compared between the lowest quartile of ST–T area (Q4) and the others (Q1–3). Results: The mean follow-up period was 53 ± 17 months. The composite endpoint was 159 cases, myocardial infarction in 27 cases and cerebral infarction in 72 cases. The lowest quartile of ST–T area (N= 1,162) had significantly more cardiovascular events than the other Q1–3 groups (N= 3,492, hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.64–3.10) after adjusting for age, gender, and other covariates. The onset of myocardial infarction did not reach statistical difference (HR 2.05, 95% CI 0.94–4.46, p=0.072), but the lowest quartile of ST–T area significantly more ischemic stroke than the other Q1–3 groups (HR 2.37, 95% CI 1.48–3.75 p<0.001) Conclusions: The lower summations of ST–T area assessed by a computerized quantitative method were associated with increased risk of cardiovascular disease, especially ischemic stroke, in patients with one or more cardiovascular risk factors.

Abstract 4137958: Transthoracic Echocardiography-based Differentiation of Hypertrophic Cardiomyopathy and Cardiac Amyloidosis

Introduction: Hypertrophic cardiomyopathy (HCM) and cardiac amyloidosis (CA) have similar features on transthoracic echocardiography (TTE) which may make the two difficult to distinguish. However, it is recognized that CA presents at an older age compared to HCM. Our aim was to determine optimal TTE parameters for differentiating HCM from CA and the incremental value of age at the time of diagnosis for differentiation of these two disorders. Methods: Patients with CA (N=121) and HCM (N=227)—diagnosed in accordance with guidelines—who underwent TTE were retrospectively identified. TTE parameters—including left ventricular global longitudinal strain (LVGLS), apical sparing ratio (ASR), AMYLoidosis Index (AMYLI), relative wall thickness (RWT) and ejection fraction to strain ratio (EFSR)—were calculated using artificial intelligence software (US2.AI) and validated by a level III echocardiography reader. Univariate and multivariable logistic regressions were used to compare TTE parameters between CA and HCM patients. Receiver operating characteristic curve (ROC) analysis was conducted to determine performance of echo parameters in distinguishing CA and HCM. Findings: CA patients were older compared to HCM ( Figure 1A ). With respect to TTE parameters, CA was associated with lower magnitude of LVGLS and higher value of ASR, AMYLI, and EFSR. LVGLS (AUC 0.865, 95% CI 0.81-0.91) outperformed AMYLI, RWT, and EFSR for differentiation of HCM from CA ( Figure 1B ). For all five TTE parameters, age provided incremental predictive value for LVGLS (p<0.001), ASR (p<0.001), AMYLI (p=0.007), RWT (p<0.001), and EFSR (p<0.001), Figure 2A-C ). LVGLS <-15.8% was 85% sensitive and 79% specific for CA. Conclusion: LVGLS is an optimal echo parameter for differentiating CA from HCM, outperforming all other traditional CA diagnostic markers. Age provides incremental diagnostic value in the differentiation of these two groups with TTE.

Unexpectedly strong heat stress induction of monoterpene, methylbutenol, and other volatile emissions for conifers in the cypress family (Cupressaceae)

We investigated the biogenic volatile organic compound (BVOC) emission rates and composition of Cupressaceae species and how the emissions change in response to moderate warming and more severe heat stress. A total of 8 species from 7 distinct Cupressaceae genera were targeted in this study and exposed to laboratory-simulated heatwaves. Each plant was enclosed in a temperature-controlled glass chamber and allowed to equilibrate at 30 °C for 24 h. The temperature was then increased stepwise from 33 °C to 43 °C in 2 °C increments, with each step lasting 2 h, and was finally kept at 45 °C for 12 h. The BVOC emissions were measured periodically using an automated air sampler coupled to a gas chromatograph.Most of the sampled Cupressaceae species (6 out of 8) were low BVOC emitters (<0.3 μgC g−1 h−1) at 30 °C. However, the BVOC emissions of all 8 species increased strongly with temperature, and in most species (5 out of 8), the emissions continued to increase with longer exposure times to heat stress. The largest increase was observed in Thuja occidentalis and Chamaecyparis thyoides, which reached maximum emissions of 350 and 190 μgC g−1 h−1, respectively. Of the different BVOCs, monoterpenes responded most strongly to heat stress, with Q10 temperature coefficients typically ranging between 7.6 and 22, which were significantly greater than the model-predicted value of 2.7. Other BVOCs including sesquiterpenes, C9 aromatics (only detected in Calocedrus decurrens), methylbutenols, and other C5 oxygenates were also induced by heat stress, but generally at a lower magnitude than monoterpenes.Our results indicate that Cupressaceae are a large but typically dormant source of reactive volatile hydrocarbons (mostly monoterpenes) whose emissions can be activated by heat stress. This phenomenon could have important implications for ozone and aerosol formation, air quality, and human health, particularly in urban areas that are prone to heatwaves.

Intrinsic 77 K Phosphorescence Characteristics and Computational Modeling of Ru(II)-(Bidentate Cyclometalated-Aromatic Ligand) Chromophores: Their Relatively Low Nonradiative Rate Constants Originating from Low Spin-Orbit Coupling Driven Vibronic Coupling Amplitudes between Emitting and Ground States.

We investigated the photoinduced relaxation of Kasha-type emitting ruthenium-(bidentate cyclometalated aromatic ligand), Ru-CM, chromophores of [Ru(pzpy)2(CM)]+ ions (CM = 1-phenylisoquinoline, 2,3-diphenylpyrazine, and 1,4-diazatriphenylene and pzpy = 2-pyrazol-1-yl-pyridine). This is the first report of the phosphorescence behavior of pure Ru-(bidentate CM) chromophores. The 77 K photoinduced relaxation characteristics of phosphorescence chromophores showed emission quantum yields higher than those of reference Ru-bpy (bpy = 2,2'-bipyridine) chromophores in the emission region of 670-900 nm. This phenomenon of the Ru-CM chromophores could be attributed to their unusually low magnitudes for 77 K nonradiative rate constants (kNRD), although their radiative rate-constants (kRAD) are not remarkable. In order to examine the 77 K photoinduced behavioral relaxation difference between Ru-CM and Ru-bpy chromophores, we used computational simulation, applying the fundamental formalism of kRAD and temperature-independent kNRD equations, which included calculated spin-orbit coupling values.

Compressive force and valgus torque are the predominant applied loads during the pivot shift exam: An in vitro study.

Despite the clinical utility of the pivot shift exam, the requisite applied forces and torques to elicit a pivot shift remain unclear. The purposes of this study are (1) to identify the greatest forces and torques applied to the knee during the pivot shift exam and (2) to evaluate if the applied loads differ among experienced surgeons. Three cadaveric hemipelvis-to-toe specimens (ages 53, 36 and 31 years; two males and one female) with no history of knee or hip injury were utilized. The experimental setup consisted of securing the hemipelvis to a mounting frame via an external fixator to simulate patient positioning during the clinical exam. The hemipelvis, femur, and tibia were spatially tracked by motion capture and the applied loads were measured using a 6-axis force-torque sensor. After sectioning the anterior cruciate ligament (ACL), three board-certified sports medicine surgeons then performed the pivot shift exam on each specimen utilizing their preferred technique. Forces (compression-distraction, anterior-posterior, and medial-lateral) and torques (varus-valgus, internal-external rotation, and flexion-extension) applied to the knee joint immediately preceding the reduction of the proximal lateral tibia during each pivot shift exam were calculated. Compression was the largest applied force averaging 95 N ± 15 N for all surgeons and knees, which was at least 4.5 times greater, on average, than the applied anterior and applied medial tibial forces (p < 0.0001). Valgus was the largest of the three applied torques, averaging 8.5 ± 2.1 Nm. Internal rotation torque was 3.7 times less, on average, than the applied valgus torque (p < 0.0001). Each surgeon applied compressive force. However, anterior force was more variable among surgeons, with one of the three surgeons applying minimal anterior force (p ≤ 0.024). The magnitude of applied torques was similar among examiners (n.s). Compressive force and valgus torque were the predominant applied loads during the pivot shift exam. A lower magnitude of internal rotation torque was also applied. The anterior force was not consistently applied among examiners. These data can better inform clinical, cadaveric, and computational studies utilizing the pivot shift exam to assess knee biomechanics and can be used to educate trainees in conducting this complex manoeuvre. An in vitro biomechanic study.

5G NR sub-THz fiber-wireless integrated systems using polarization multiplexing-multiband technique and self-polarization diversity scheme

Fifth generation (5G) new radio (NR) fiber-wireless integrated systems using polarization multiplexing-multiband technique and self-polarization diversity scheme are successfully implemented. Polarization multiplexing-multiband technique is an effectual method to enhance the transmission capacity and spectral efficiency of systems. Self-polarization diversity scheme is an efficient scheme for polarization demultiplexing, in which an x-polarized (y-polarized) optical carrier with multiple x-polarized (y-polarized) optical signals can be detected using single-ended photodiodes. The transmission of 5G NR sub-terahertz (THz) signals through fiber-wireless integrated systems holds promise to afford high-speed and long-haul wired-wireless communications. It shows the robustness to achieve high aggregate data rates and lays the foundation to meet the evolving demands of future communication systems. Through an integrated medium of 20 km single-mode fiber, 1.6 km optical wireless, and 4/8/12 m 5G NR wireless, four 5G sub-THz 32-quadrature amplitude modulation-orthogonal frequency-division multiplexing signals at x- and y-polarizations are transmitted with good transmission performance in terms of low bit error rates and error vector magnitudes. The successful transmission of sub-THz signals at different carrier frequencies and polarizations over fiber-wireless integrated systems proves system’s ability to support cutting-edge 5G NR fiber-wireless integrated systems.