Differential Shift Research Articles

The effect of the duration of treatment with antioxidants on age-related hearing loss

Background and aims The effect of antioxidants depends on several factors, including the type, dose, timing, and treatment duration. Several studies have demonstrated that antioxidants can prevent age-related hearing loss (ARHL), however, a few studies have focussed on the role of factors influencing the effects of antioxidant therapy. This study aimed to investigate the effect of duration of treatment on ARHL using an herbal antioxidant, silymarin, in a D-galactose-induced ageing rat model. Method 40 three-months-old Wistar rats were divided into four groups: a short-term silymarin-treated group that received 500 mg/kg/day D-galactose (8 consecutive weeks) +200 mg/kg/day silymarin (4 consecutive weeks), long-term silymarin-treated group received 500 mg/kg/day D-galactose (8 consecutive weeks)+ 200 mg/kg/day silymarin (8 consecutive weeks), placebo group received 500 mg/kg/day D-galactose + placebo (propylene glycol; 8 consecutive weeks), and control group received normal saline (8 consecutive weeks). Auditory Brainstem Response (ABR) was measured at 4, 8, 12, and 16 kHz frequencies before and after the intervention. Results No significant differences were found in ABR absolute and inter-peak latencies between groups. In contrast, there was a significant difference in ABR threshold shift between the placebo and the long-term silymarin-treated groups at 4 and 16 kHz frequencies (p ≤ .05), but without a similar difference through comparison with the short-term silymarin-treated group (p > .05). Additionally, a significant decrease in ABR amplitude of PI and PII was observed in the placebo group at 4 kHz frequency compared to the long-term silymarin-treated group (p ≤ .05), but not to the short-term silymarin-treated group (p > .05). Conclusion The present study results indicate that the duration of treatment with antioxidants influences the successful prevention and treatment of ARHL. Consequently, this factor must be considered in the antioxidant therapy of ARHL. However, further studies are required to fully evaluate the effects of optimal treatment duration with antioxidants on ARHL along with the other influencing factors.

Motor adaptation via distributional learning

Objective. Both artificial and biological controllers experience errors during learning that are probabilistically distributed. We develop a framework for modeling distributions of errors and relating deviations in these distributions to neural activity. Approach. The biological system we consider is a task where human subjects are required to learn to minimize the roll of an inverted T-shaped object with an unbalanced weight (i.e. one side of the object is heavier than the other side) during lift. We also collect BOLD activity during this process. For our experimental setup, we define the state of the system to be the maximum magnitude roll of the object after lift onset and give subjects the goal of achieving the zero state. Main Results. We derive a model for this problem from a variant of Temporal Difference Learning. We then combine this model with Distributional Reinforcement Learning (DRL), a framework that involves defining a value distribution by treating the reward as stochastic. This model transforms the goal of the controller from achieving a target state, to achieving a distribution over distances from the target state. We call it a Distributional Temporal Difference Model (DTDM). The DTDM allows us to model errors in unsuccessfully minimizing object roll using deviations in the value distribution when the center of mass of the unbalanced object is changed. We compute deviations in global neural activity and show that they vary continuously with deviations in the value distribution. Different aspects might contribute to this global shift or signal difference, including a difference in grasp and lift force at lift onset, as well as sensory feedback of error/roll after lift onset. We predict that there exists a coordinated, global response to errors that incorporates all of this information, which is encoding the DTDM objective and used on subsequent trials enabling success. We validate the utility of the DTDM as a model for biological adaptation by using it to engineer a robotic controller to solve a similar problem. Significance. We develop a novel theoretical framework and show that it can be used to model a non-trivial motor learning task. Because this theoretical framework is consistent with state-of-the-art reinforcement learning, we can also use it to program a robot to perform a similar task. These results suggest a way to model the multiple subsystems composing global neural activity in a way that transfers well to engineering artificial intelligence.

Detection and assessment scheme of voltage and current unbalance for three phase synchronous generators using dual numerical techniques based on correlation and deviation percentage concepts

A differentiation in three-phase voltages or currents is termed as unbalance. Unbalance can be caused by unbalanced loads and power system faults. This disturbance results in serious problems in system elements, particularly to synchronous generators, due to the deviation of magnitude, frequency or phase shift. The ability to detect unbalance as well as to identify the severity level of unbalance is very important in power grids. This paper describes a protection scheme for voltage and current unbalance in synchronous generators. The scheme is based on dual numerical techniques application utilizing correlation and deviations percentages for voltage and current signals to detect and assess the unbalance situations. Different types of disturbances are simulated to verify the effectiveness of the proposed scheme using ATP and MATLAB programs. The simulation results prove that the scheme is successful for unbalance detection and assessment of synchronous generators. The different faults and operating conditions have no effect on the proposed scheme reliability. Also, the results show that the proposed scheme is able to classify the unbalance into different severity levels. Besides the obtained results reveal this scheme is effective and secure to the acceptable overloading and temporary faults in power systems.

Concentration-Dependent Solvation Structure and Dynamics of Aqueous Sulfuric Acid Using Multinuclear NMR and DFT.

Sulfuric acid is a ubiquitous compound for industrial processes, and aqueous sulfate solutions also play a critical role as electrolytes for many prominent battery chemistries. While the thermodynamic literature on it is quite well-developed, comprehensive studies of the solvation structure, particularly molecular-scale dynamical and transport properties, are less available. This study applies a multinuclear nuclear magnetic resonance (NMR) approach to the elucidation of the solvation structure and dynamics over wide temperature (-10 to 50 °C) and concentration (0-18 M) ranges, combining the 17O shift, line width, and T1 relaxation measurements, 33S shift and line width measurements, and 1H pulsed-field gradient NMR measurements of proton self-diffusivity. In conjunction, these results indicate a crossover between two regimes of solvation structure and dynamics, occurring above the concentration associated with the deep eutectic point (∼4.5 M), with the high-concentration regime dominated by a strong water-sulfate correlation. This description was borne out in detail by the activation energy trends with increasing concentration derived from the relaxation of both the H2O/H3O+ and H2SO4/HSO4-/SO42- 17O resonances and the 1H self-diffusivity. However, the 17O chemical shift difference between the H2O/H3O+ and H2SO4/HSO4-/SO42- resonances across the entire temperature range is nevertheless strikingly linear. A computational approach coupling molecular dynamics simulations and density functional theory NMR shift calculations to reproduce this trend is presented, which will be the subject of further development. This combination of multinuclear, dynamical NMR, and computational methods, and the results furnished by this study, will provide a platform for future studies on battery electrolytes where aqueous sulfate chemistry plays a central role in the solution structure.

The Challenge of Accurate Computation of Two-Photon Absorption Properties of Organic Chromophores in the Condensed Phase.

Two strategies are applied to evaluate the effect of the environment on the two-photon absorption (TPA) cross sections for two characteristic excited states of C2H4 upon complexation with H2O. The supermolecular strategy provides the reference complexation-induced shifts and uses either the EOM-CCSD or ADC(2) method. The embedding strategy is based on frozen-density-embedding theory (FDET) and uses only fundamental constants. The TPA cross sections from high-level supermolecular calculations are extremely basis-set-sensitive. Literature data and the present study indicate that accuracy of the absolute TPA cross sections below 100 atomic units and their shifts below 10 atomic units remains a challenge. The obtained FDET results show a similar basis-set behavior. For the largest basis set (d-aug-cc-pVQZ), TPA cross sections obtained from these two strategies are in excellent agreement. The complexation-induced shifts have the correct sign of the effect and a small (12-33%) relative error in magnitude. The deviations of the FDET-derived shifts from the reference are of similar magnitude as the reliability threshold of the reference shifts.

All-polarization-maintaining linear fiber laser mode-locked by nonlinear polarization evolution with phase bias

We report on a novel architecture for robust all polarization-maintaining (PM) femtosecond linear fiber lasers mode-locked by nonlinear polarization evolution (NPE) with phase bias. Due to a non-reciprocal phase shift, the reflectivity of the artificial saturable absorber has a steeper slope around zero difference in nonlinear phase shift between the orthogonal polarizations, offering the possibility to reduce mode locking threshold and reach high repetition rates. We demonstrate an environmentally stable self-starting 105 MHz repetition rate linear Yb:fiber laser based on NPE with phase bias mode locking. The laser delivers an average power of 26.3 mW and 332 fs pulse which is further compressed to 91 fs at a pump power of 425 mW. Our work provides a novel promising compact and robust femtosecond laser for ultrafast photonic applications.

804 A Multidisciplinary Approach to Investigating Sleep Practices and Sleep Disturbances on an Inpatient Neurology Unit

Abstract Introduction Minimizing nightly disruptions in the inpatient setting requires a multidisciplinary, collaborative approach. Our aim was to assess staff perceptions and practices of sleep during hospitalization to help identify and prioritize improvement initiatives. Methods An online survey was distributed to inpatient staff (nurses, residents, attendings, APPs) on a neurology unit at an academic medical center. The survey assessed sleep disturbances, sleep knowledge and sleep practices. Responses across groups were analyzed using Cochran Armitage tests. Cumulative logit model was also performed. Results Among the 49 respondents, 75% reported not having the training to diagnose and treat sleep disorders. 51.2% rarely or never asked about sleep quality or duration prior to admission. 29.6% rarely or never tracked the amount and quality of sleep during hospitalization. Reasons for not tracking or considering sleep included “not being a priority”, “no place to document” and “not being there at night.” Overall, staff ranked noise, testing and vital sign checks as most disruptive to sleep quality and temperature as least disruptive. However, nurses perceived medication administration (p=0.0001) and testing (p=0.0296) more disruptive than the ordering providers. Multivariable analysis showed nurses ranked medication administration higher than providers when shift differences were controlled (p< 0.01). Evening/night shift workers ranked pain (p=0.0324) and anxiety (p=0.0360) higher than day shift workers. Those comfortable with diagnosing and treating sleep disorders were more likely to track sleep during admission (p=0.009), allow patients to sleep during medication administration times (p=0.0189) and allow sleep during scheduled lab draws (p=0.0189). Conclusion Our findings indicate that differences in sleep knowledge and sleep perspectives exist across the healthcare team. Possible explanations include training differences, ordering providers not knowing what time medications are administered or when tests are done, teams not clarifying whether nighttime orders are critical and nurses lacking empowerment to notify providers that sleep is being disrupted. Hand offs may need optimization with regards to pain and anxiety. A multidisciplinary approach, particularly between providers/nurses and night/day teams is critical to improve sleep on inpatient units. Our next steps include surveying patients, tracking nightly disruptions using EMR and decreasing unnecessary overnight orders using a team based approach. Support (if any):

Synthesis-Driven Stereochemical Assignment of Marine Polycyclic Ether Natural Products.

Marine polycyclic ether natural products have gained significant interest from the chemical community due to their impressively huge molecular architecture and diverse biological functions. The structure assignment of this class of extraordinarily complex natural products has mainly relied on NMR spectroscopic analysis. However, NMR spectroscopic analysis has its own limitations, including configurational assignment of stereogenic centers within conformationally flexible systems. Chemical shift deviation analysis of synthetic model compounds is a reliable means to assign the relative configuration of “difficult” stereogenic centers. The complete configurational assignment must be ultimately established through total synthesis. The aim of this review is to summarize the indispensable role of organic synthesis in stereochemical assignment of marine polycyclic ethers.

Conformational features and ionization states of Lys side chains in a protein studied using the stereo-array isotope labeling (SAIL) method.

Although both the hydrophobic aliphatic chain and hydrophilic -amino group of the Lys side chain presumably contribute to the structures and functions of proteins, the dual nature of the Lys residue has not been fully investigated using NMR spectroscopy, due to the lack of appropriate methods to acquire comprehensive information on its long consecutive methylene chain. We describe herein a robust strategy to address the current situation, using various isotope-aided NMR technologies. The feasibility of our approach is demonstrated for the PHS/V66K variant of staphylococcal nuclease (SNase), which contains 21Lys residues, including the engineered Lys-66 with an unusually low p of 5.6. All of the NMR signals for the 21Lys residues were sequentially and stereospecifically assigned using the stereo-array isotope-labeled Lys (SAIL-Lys), [U-C,N; ,,,-D]-Lys. The complete set of assigned H, C, and N NMR signals for the Lys side-chain moieties affords useful structural information. For example, the set includes the characteristic chemical shifts for the C, C, and N signals for Lys-66, which has the deprotonated -amino group, and the large upfield shifts for the H and C signals for the Lys-9, Lys-28, Lys-84, Lys-110, and Lys-133 side chains, which are indicative of nearby aromatic rings. The C and N chemical shifts of the SNase variant selectively labeled with either [-C;,-D]-Lys or SAIL-Lys, dissolved in HO and DO, showed that the deuterium-induced shifts for Lys-66 were substantially different from those of the other 20Lys residues. Namely, the deuterium-induced shifts of the C and N signals depend on the ionization states of the -amino group, i.e., 0.32 ppm for C [ND-NH] vs. 0.21 ppm for C [ND-NH] and 1.1 ppm for N[ND-NH] vs. 1.8 ppm for N[ND-NH]. Since the 1D C NMR spectrum of a protein selectively labeled with [-C;,-D]-Lys shows narrow ( 2 Hz) and well-dispersed C signals, the deuterium-induced shift difference of 0.11 ppm for the protonated and deprotonated -amino groups, which corresponds to 16.5 Hz at a field strength of 14 T (150 MHz for C), could be accurately measured. Although the isotope shift difference itself may not be absolutely decisive to distinguish the ionization state of the -amino group, the C, C, and N signals for a Lys residue with a deprotonated -amino group are likely to exhibit distinctive chemical shifts as compared to the normal residues with protonated -amino groups. Therefore, the isotope shifts would provide a useful auxiliary index for identifying Lys residues with deprotonated -amino groups at physiological pH levels.

A GPS signal acquisition algorithm for the high orbit space

In the high orbit space, the visibility of GPS main lobe signal is poor due to the earth's occlusion and the increase in signal transmission distance. Therefore, the side lobe signals are essential for navigation mission, which puts forward higher requirements for the sensitivity of the receiver. In addition, the cross-correlation interference (CCI) caused by the large power difference between the main and side lobe signals is serious and results in the false acquisition of the side lobe signals. To improve the acquisition sensitivity and stability of the receiver, we designed a GPS signal acquisition algorithm for the high orbit space. The characteristics of high orbit GPS signal are analyzed according to the propagation process of GPS signal link. The influence of CCI on the acquisition performance of the side lobe signals is explored. Based on the parallel code phase search method, the coherent accumulation and incoherent accumulation are combined to improve the acquisition sensitivity. At the same time, according to the different probability distribution characteristics of autocorrelation peak and cross-correlation peaks in the correlator output, CCI is detected by means of hypothesis testing. The strong signals are reconstructed by using the amplitudes, code phases and Doppler shifts provided by the tracking loop. The CCIs are estimated by correlating the reconstructed strong signals with the local duplicated signals and eliminated from the correlation results of the side lobe signals to obtain the correct acquisition results. Simulation results show that the proposed algorithm can eliminate the CCIs in the high orbit space and improve the acquisition sensitivity of the receiver. Moreover, the CCIs under different Doppler shift differences of the main and side lobe signals can be effectively eliminated.

Effect of solvent on the electronic absorption spectral properties of mixed β-octasubstituted free base tetraphenylporphyrins

A near planar macrocycle containing 2,3,12,13-tetraphenylethynyl-5,10,15,20-tetrakis-(4[Formula: see text]-[Formula: see text]-butylphenyl)porphyrin, H2T(4[Formula: see text]-[Formula: see text]-Bu Ph)P(PE)4 and a series of antipodally mixed substituted nonplanar porphyrins, 2,3,5,10,12,13,15,20-octaphenyl-7,8,17,18-tetra(2[Formula: see text]-thienyl/phenylethynyl, PE)porphyrin, H2OPP(2[Formula: see text]-Th/PE)4 and 2,3,12,13-tetramethyl-7,8,17,18-tetra(2[Formula: see text]-thienyl/PE)-5,10,15,20-tetraphenylporphyrin, H2TPP(CH[Formula: see text](2[Formula: see text]-Th/PE)4were examined by electronic absorption spectroscopy in twenty different solvents. The presence of push-pull substituents at the antipodal [Formula: see text]-pyrrole positions of the nonplanar macrocycle induces varying degrees of orthogonal dipole moments to the porphyrin ring. The influence of different solvents on the degree of nonplanarity and electronic nature of the macrocycle on their electronic absorption spectral properties were examined. Generally, free base porphyrins showed dramatic solvent dependent absorption spectral band shifts and follow the order: H2OPP(PE)4 > H2OPP(2[Formula: see text]-Th)[Formula: see text] H2TPP(CH[Formula: see text](2[Formula: see text]-Th)4 >[Formula: see text]H2TPP(CH[Formula: see text](PE)4 > H2T(4[Formula: see text]-[Formula: see text]Bu Ph)P(PE)4. Absorption spectral data in different solvents was analyzed using selected solvatochromic parameters, ([Formula: see text] – 1)/(2[Formula: see text] + 1), [Formula: see text] (30),[Formula: see text], and [Formula: see text]*. The enhanced red-shift of the absorption bands of the mixed substituted porphyrins in polar solvents was influenced by solvent-core (porphyrin) interaction and is reflected from the 1H NMR chemical shift of the core imino-hydrogens in polar solvents relative that observed in less polar solvents. The magnitude of the difference in chemical shift ([Formula: see text], ppm) of imino-hydrogens in DMSO-d6 relative to that in CDCl3 follow the order: H2TPP(CH[Formula: see text](2[Formula: see text]-Th)4 (1.37 ppm) > H2OPP(PE)4 (1.17 ppm) > H2TPP(CH[Formula: see text](PE)4 (0.57 ppm). The large red-shift in B and Q bands in polar solvents relative to apolar (or less polar) solvents has been possible due to the combined effect of the electronic nature of the macrocycle, its nonplanarity, and solvent-porphyrin core interactions.

NMR studies of adsorption and diffusion in porous carbonaceous materials

Porous carbonaceous materials have many important industrial applications including energy storage, water purification, and adsorption of volatile organic compounds. Most of their applications rely upon the adsorption of molecules or ions within the interior pore volume of the carbon particles. Understanding the behaviour and properties of adsorbate species on the molecular level is therefore key for optimising porous carbon materials, but this is very challenging owing to the complexity of the disordered carbon structure and the presence of multiple phases in the system. In recent years, NMR spectroscopy has emerged as one of the few experimental techniques that can resolve adsorbed species from those outside the pore network. Adsorbed, or “in-pore” species are shielded with respect to their free (or “ex-pore”) counterparts. This shielding effect arises primarily due to ring currents in the carbon structure in the presence of a magnetic field, such that the observed chemical shift differences upon adsorption are independent of the observed nucleus to a first approximation. Theoretical modelling has played an important role in rationalising and explaining these experimental observations. Together, experiments and simulations have enabled a large amount of information to be gained on the adsorption and diffusion of adsorbed species, as well as on the structural and magnetic properties of the porous carbon adsorbent. Here, we review the methodological developments and applications of NMR spectroscopy and related modelling in this field, and provide perspectives on possible future applications and research directions.

Temperature-dependent Goos-Hänchen shifts in a symmetrical graphene-cladding waveguide

We theoretically investigate the temperature-dependent Goos-Hänchen (GH) shifts in a symmetrical graphene-cladding waveguide (SGCW). The GH shifts in SGCW present a quasi-periodic tendency near the resonance angle with the change of temperature, which can mainly be attributed to the temperature dependence of the guiding layer’s thickness, instead of the graphene intraband conductivity and guiding layer’s refractive index. Importantly, tiny temperature fluctuations can cause significant deviations in GH shifts, and the deviations can be efficiently improved by adjusting the Fermi energy. Therefore, we propose a high-sensitivity temperature sensing scheme based on GH shifts in the SGCW, and the maximum sensitivity can reach up to −2.2 × 105 μm/°C. These researches may open avenues for applications of optical temperature sensors.

Rupture directivity of the 25 November 2018 Taiwan Strait Mw5.8 earthquake and its tectonic implications

Taiwan Strait is located between the actively deforming Taiwan Island and stable South China Craton. While strong earthquakes have occurred on the east and west sides of the Taiwan Strait and their seismotectonic are relatively well understood, the earthquake risk and seismogenic structure in the strait still need more investigations. On November 25, 2018, a rare moderately strong earthquake with a magnitude of Mw5.8 occurred inside the strait, and it caused broad ground motions in the near regions. From the waveform inversion of the seismic data, this earthquake is found to be a high-dip angle strike-slip event, with the two nodal planes striking east-west (EW) and north-south (NS) directions. As there are mapped faults striking EW and NS in the epicentral region, further studies are needed to determine the ruptured fault plane. To determine the ruptured fault plane, we analyzed the rupture directivity of the mainshock with the relative location between the hypocenter and the centroid. We chose several M4+ aftershocks as reference events and relocated the reference earthquakes with the Pn travel time difference. Then, we used regional waveform data to invert centroid location and source parameters of earthquakes. Thereafter, we estimated the strike of the mainshock ruptured fault and rupture length, via fitting the azimuthal variation of the Love wave time shift difference between the mainshock and the reference earthquakes. Our results showed that the mainshock ruptured along NS strike with the rupture length about 3.6–5.6 km. Combined with the tectonics, we inferred that the seismogenic fault is the Dongshan uplift eastern fault (DSEF) and the 1994 event may promote the occurrence of the 2018 Mw5.8 earthquake.

Effects of extreme temperature on China’s tea production

The production of tea (Camellia sinensis (L.) Kuntze), the world’s second most consumed beverage, is susceptible to extreme weather events. However, our understanding about the impacts of extreme temperatures and climate change on tea yields remains fairly limited. Here we quantify the historical and predict future fluctuations in tea yield caused by extreme temperatures in China, the largest tea producing country. We found that both heat and cold extremes were associated with significantly reduced tea yields. In the present climate, dominating cold extremes influence more than half of China’s tea production, with a maximum of 56.3% reduced annual production. In the near future, we predict positive net impacts of climate change on tea yield in all study regions at both the 1.5 °C and 2.0 °C global warming levels. Climate warming may diminish the negative impacts of cold extremes to 14%, especially at the current most affected northern tea growing regions (>28° N). However, new areas of yield reduction by intensified heat extremes will emerge, up to 14%–26% yield losses estimated at the Yangtze River (∼30° N) and southern China (<∼25° N) regions. Although the Paris Agreement targets limiting global warming to 1.5 °C, we expect up to 11%–24% heat-induced yield loss in Chongqing, Hunan, Anhui, and Zhejiang. Increasing heat extremes pose the most challenging changes for tea production in China. Therefore, addressing the regional difference of extreme temperature shifts is urgent for adapting tea production to climate change.

Systematic Approach to Find the Global Minimum of Relaxation Dispersion Data for Protein-Induced B-Z Transition of DNA.

Carr–Purcell–Meiboom–Gill (CPMG) relaxation dispersion spectroscopy is commonly used for quantifying conformational changes of protein in μs-to-ms timescale transitions. To elucidate the dynamics and mechanism of protein binding, parameters implementing CPMG relaxation dispersion results must be appropriately determined. Building an analytical model for multi-state transitions is particularly complex. In this study, we developed a new global search algorithm that incorporates a random search approach combined with a field-dependent global parameterization method. The robust inter-dependence of the parameters carrying out the global search for individual residues (GSIR) or the global search for total residues (GSTR) provides information on the global minimum of the conformational transition process of the Zα domain of human ADAR1 (hZαADAR1)–DNA complex. The global search results indicated that a α-helical segment of hZαADAR1 provided the main contribution to the three-state conformational changes of a hZαADAR1—DNA complex with a slow B–Z exchange process. The two global exchange rate constants, kex and kZB, were found to be 844 and 9.8 s−1, respectively, in agreement with two regimes of residue-dependent chemical shift differences—the “dominant oscillatory regime” and “semi-oscillatory regime”. We anticipate that our global search approach will lead to the development of quantification methods for conformational changes not only in Z-DNA binding protein (ZBP) binding interactions but also in various protein binding processes.

Isolated reefs support stable fish communities with high abundances of regionally fished species.

Anthropogenic impacts at isolated and inaccessible reefs are often minimal, offering rare opportunities to observe fish assemblages in a relatively undisturbed state. The remote Rowley Shoals are regarded as one of the healthiest reef systems in the Indian Ocean with demonstrated resilience to natural disturbance, no permanent human population nearby, low visitation rates, and large protected areas where fishing prohibitions are enforced. We used baited remote underwater video systems (BRUVS) to quantify fish assemblages and the relative abundance of regionally fished species within the lagoon, on the slope and in the mesophotic habitat at the Rowley Shoals at three times spanning 14 years and compared abundances of regionally fished species and the length distributions of predatory species to other isolated reefs in the northeast Indian Ocean. Fish assemblage composition and the relative abundance of regionally fished species were remarkably stable through time. We recorded high abundances of regionally fished species relative to other isolated reefs, including globally threatened humphead Maori wrasse (Cheilinus undulatus) and bumphead parrotfish (Bolbometopon muricatum). Length distributions of fish differed among habitats at the Rowley Shoals, suggesting differences in ontogenetic shifts among species. The Cocos (Keeling) Islands typically had larger‐bodied predatory species than at the Rowley Shoals. Differences in geomorphology, lagoonal habitats, and fishing history likely contribute to the differences among remote reefs. Rowley Shoals is a rare example of a reef system demonstrating ecological stability in reef fish assemblages during a time of unprecedented degradation of coral reefs.

Impaired Weight-Shift Amplitude in People with Parkinson's Disease with Freezing of Gait.

People with Parkinson's disease and freezing of gait (FOG; freezers) suffer from pronounced postural instability. However, the relationship between these phenomena remains unclear and has mostly been tested in paradigms requiring step generation. To determine if freezing-related dynamic balance deficits are present during a task without stepping and determine the influence of dopaminergic medication on dynamic balance control. Twenty-two freezers, 16 non-freezers, and 20 healthy age-matched controls performed mediolateral weight-shifts at increasing frequencies when following a visual target projected on a screen (MELBA task). The amplitude and phase shift differences between center of mass and target motion were measured. Balance scores (Mini-BESTest), 360° turning speed and the freezing ratio were also measured. Subjects with Parkinson's disease were tested ON and partial OFF (overnight withdrawal) dopaminergic medication. Freezers had comparable turning speed and balance scores to non-freezers and took more levodopa. Freezers produced hypokinetic weight-shift amplitudes throughout the MELBA task compared to non-freezers (p = 0.002), which were already present at task onset (p < 0.001). Freezers also displayed an earlier weight-shift breakdown than controls when OFF-medication (p = 0.008). Medication improved mediolateral weight-shifting in freezers and non-freezers. Freezers decreased their freezing ratio in response to medication. Hypokinetic weight-shifting proved a marked postural control deficit in freezers, while balance scores and turning speed were similar to non-freezers. Both weight-shift amplitudes and the freezing ratio were responsive to medication in freezers, suggesting axial motor vigor is levodopa-responsive. Future work needs to test whether weight-shifting and freezing severity can be further ameliorated through training.

An objective, markerless videosystem for staging facial palsy

PurposeTo propose a new objective, video recording method for the classification of unilateral peripheral facial palsy (UPFP) that relies on mathematical algorithms allowing the software to recognize numerical points on the two sides of the face surface that would be indicative of facial nerve impairment without positioning of markers on the face.MethodsPatients with UPFP of different House–Brackmann (HB) degrees ranging from II to V were evaluated after video recording during two selected facial movements (forehead frowning and smiling) using a software trained to recognize the face points as numbers. Numerical parameters in millimeters were obtained as indicative values of the shifting of the face points, of the shift differences of the two face sides and the shifting ratio between the healthy (denominator) and the affected side (numerator), i.e., the asymmetry index for the two movements.ResultsFor each HB grade, specific asymmetry index ranges were identified with a positive correlation for shift differences and negative correlation for asymmetry indexes.ConclusionsThe use of the present objective system enabled the identification of numerical ranges of asymmetry between the healthy and the affected side that were consistent with the outcome from the subjective methods currently in use.

Photophysical Characteristics of Polarity‐Sensitive and Lipid Droplet‐Specific Phenylbenzothiadiazoles

AbstractIn this study, we present a series of solvatochromic phenylbenzothiadiazoles that display dual emission from the locally excited (LE) and intramolecular charge transfer (ICT) excited states. The donor‐acceptor derivatives are highly sensitive to polarity changes, which can be monitored by differences in emission efficiency, spectroscopic shifts and variations of the LE/ICT ratio. One of the compounds in the series, containing a thiomethyl substituent, emerged as an excellent blue emitting stain for intracellular lipid droplets, a biomarker for various types of cancer. In addition, a non‐emissive nitro derivative becomes fluorescent upon bioreduction in hypoxic cancer cells and accumulates in lipid droplets with a high signal‐to‐background ratio.