Asymmetric metamaterial sandwich structure with NIM characteristics for THz imaging application

This study presented a unique, miniaturised asymmetric interconnected vertical stripe (IVS) design for terahertz (THz) frequency applications. Therefore, this research aimed to achieve a frequency response of 0 to 10 THz using a 5 × 5 µm2 Silicon (Si) substrate material. Meanwhile, various parametric examinations were conducted to investigate variations in the performance. For example, the unit cell selection process was carefully examined by using various design structures and modifying the structure by adding split gaps and connecting bars between vertical stripes. Furthermore, the proposed sandwich structure design was used to compute the absorbance and reflectance properties. All the analytical examinations were executed utilising the Computer Simulation Technology (CST) 2019 software. The introduced IVS metamaterial exhibits negative index behaviour and has a single resonance frequency of 5.23 THz with an acceptable magnitude of - 24.38 dB. Additionally, the quadruple-layer IVS structure exhibits optimised transmission coefficient behaviour between 3 and 6 THz and 7 to 9 THz, respectively. However, the magnitude of the transmission coefficient increased with the number of material layers. Besides that, the absorbance study shows that using a quadruple-layer structure obtains unique and promising results. Overall, the proposed asymmetric IVS metamaterial design achieves the required performance by using a compact structure rather than extending the dimensions of the design.

Asymmetric response of vegetation GPP to impervious surface expansion: Case studies in the Yellow and Yangtze River Basins

Terrestrial gross primary production (GPP) changes due to impervious surfaces significantly impact ecosystem services in watersheds. Understanding the asymmetric response of vegetation GPP to impervious surface expansion is essential for regional development planning and ecosystem management. However, the asymmetric response of vegetation GPP to the impacts of impervious surface expansion is unknown in different watersheds. This paper selected the Yellow River and Yangtze River basins as case studies. We characterized the overall change in GPP based on changes in impervious surface ratio (ISR), determined impervious surface expansion's direct and indirect impacts on GPP in the two watersheds, and further analyzed the asymmetric response of the compensatory effects of indirect influences on the impervious surface expansion in different watersheds. The results showed that: (1) The vegetation GPP decreased with increasing ISR in the Yangtze River Basin, while that in the Yellow River Basin first increased and then reduced. (2) The direct impacts of increased ISR reduced vegetation GPP, while the indirect impacts both had a growth-compensating effect. Growth compensation stabilized at approximately 0.40 and 0.30 in the Yellow and Yangtze River Basins. (3) When the ISR was 0.34-0.56, the growth compensation could offset the reduction of GPP due to direct impact and ensure that the background vegetation GPP was not damaged in the Yellow River Basin. In contrast, the background vegetation GPP was inevitably impaired with increased ISR in the Yangtze River Basin. Therefore, this study suggests that the ISR should be ensured to be between 0.34 and 0.56 to maximize the impervious surface of the Yellow River Basin without compromising the background vegetation GPP. While pursuing impervious surface expansion in the Yangtze River Basin, other programs should be sought to compensate for the loss to GPP.

A novel asymmetric horizontal splitting fracture of the lumbar spine: pediatric case report of a lateral bending, flexion and distraction fracture

BACKGROUND

There are many lateral bending fracture cases presented in the literature that mostly involve facet dislocations or corpus collapse. In this report, we aim to describe a novel asymmetric lateral bending, flexion and distraction fracture, propose a mechanism, and delineate its clinical importance.

CASE DESCRIPTION

A 13-year-old girl arrived at our trauma center 12 hours after a head-on truck collision. She had paraplegia, and her imaging revealed a spinal cord avulsion at the T10 level and a horizontal fracture at the L4 spinous process, left lamina, left pedicle, and left posterior-upper corner of the corpus, extending through the right lamina. Her posterior ligamentous complex, right facet joint, pedicle, and right side of the corpus were spared from the injury. The patient stated that she had been sitting on the right side of the back seat, turned toward her cousin in the middle. Her left leg was externally rotated and flexed on the seat while her right foot was on the floor at the time of the accident. The patient was managed conservatively with an orthosis. At follow-up, the patient was free of back pain and no lumbar kyphosis developed.

CONCLUSION

The flexion-distraction injuries mostly require surgical stabilization according to TLICS classification, because of the instability. In this particular case, TLICS classification was not adequate for a treatment decision, and the conservative treatment came out to be a more than sufficient treatment option.

Boosting oxygen reduction reaction kinetics through perturbating electronic structure of single-atom Fe-N3S1 catalyst with sub-nano FeS cluster

Single atomic Fe-N4 catalyst exhibits a great prospect for oxygen reduction reaction (ORR) and adjusting the intrinsic coordination structure and the carbon matrix structure effectively improves the catalytic activity. However, controlling the active site coordination structure and its surrounding environment at atomic level remains a challenge. In this paper, Fe-N3S1 and FeS sub-nano cluster were innovatively concatenated on S, N co-doped carbon matrix (SNC), denoted as FeS/FeSA@SNC catalysts, for modulating ORR catalysis performance. Both experimental measurements and theoretical calculations have confirmed that the local electron configuration of Fe center is modulated by this unique structure combination leading to optimized ORR kinetics. Based on this design, the synthesized FeS/FeSA@SNC delivers ORR activity with a half-wave potential of 0.9 V (vs. RHE), excelling that of commercial Pt/C (0.87 V) and the Zn-air battery (ZAB) with this cathode catalyst delivers a peak power density of 126 mW cm-2. This work presents a novel strategy for manipulating the single-atom active sites through control the local coordination structure and provides a reference for the development of novel efficient ORR electrocatalysts.

Organocatalytic Asymmetric Domino [3+2]-Cycloaddition-Acyl Transfer Reaction between Azomethine Ylides and α-Nitro-α,β-Unsaturated Ketones

Herein we have developed an organocatalytic asymmetric domino [3+2]-cycloaddition-acyl transfer reaction between in situ generated azomethine ylides and α-nitro-α,β-unsaturated ketones. The desired penta-substituted pyrrolidine products were obtained in high yields and in moderate to good enantio- and diastereoselectivities. Also, an isomerization reaction in silica gel was performed for the formation of another diastereomer in high yields with retention of enantioselectivities.

The effects of axial twisting and material non-symmetry on arterial bent buckling

Artery buckling occurs due to hypertensive lumen pressure or reduced axial tension and other pathological conditions. Since arteries in vivo often experience axial twisting and the collagen fiber alignment in the arterial wall may become nonsymmetric, it is imperative to know how axial twisting and nonsymmetric collagen alignment would affect the buckling behavior of arteries. To this end, the objective of this study was to determine the effect of axial twisting and nonsymmetric collagen fiber distribution on the critical pressure of arterial bent buckling. The buckling model analysis was generalized to incorporate an axial twist angle and nonsymmetric fiber alignment. The effect of axial twisting on the critical pressure was simulated and experimentally tested in a group of porcine carotid arteries. Our results showed that axial twisting tends to reduce the critical pressure depending on the axial stretch ratio and twist angle. In addition, nonsymmetric fiber alignment reduces the critical pressure. Experimental results confirmed that a twist angle of 90° reduces the critical pressure significantly (p < 0.05). It was concluded that axial twisting and non-axisymmetric collagen fibers distribution could make arteries prone to bent buckling. These results enrich our understanding of artery buckling and vessel tortuosity. The model analysis and results could also be applicable to other fiber reinforced tubes under lumen pressure and axial twisting.

Asymmetric bilateral traumatic hip dislocation: Report of two cases

INTRODUCTION AND IMPORTANCE

Asymmetric bilateral hip dislocation is an extremely rare condition. The mechanism of injury and severity are variables. We reported two cases of asymmetric bilateral hip dislocation with different pattern of injury and different onset of injury.

CASE PRESENTATION

The first case was a male 20 years old with 7 months neglected asymmetric bilateral hip dislocation. Total hip arthroplasty (THA) was performed on both hips, which resulted in good clinical outcomes. The second case was a male 32 years old with acute right open anterior dislocation (obturator type) and left posterior fracture-dislocation. Emergency debridement and open reduction were performed on the patients with reduction and fixation for the left hip.

CLINICAL CASE DISCUSSION

To the best of our knowledge, this is the first reported case of open anterior hip dislocation with exposed femoral head on inguinal area in the setting of asymmetric bilateral hip dislocation. Furthermore, this article also presented another case with >6 months neglected time along with the surgical treatment.

CONCLUSIONS

Asymmetric bilateral hip dislocation is a rare injury which usually associated with high-energy trauma. Open injury with the exposed femoral head is possible to occur in this kind of rare case. In the setting of long-term neglected cases, total hip arthroplasty could be recommended as the treatment choice.

Asymmetric, biraphid diatoms from the Laurentian Great Lakes

This taxonomic account of light micrographs from the coastal Laurentian Great lakes contains taxa from the diatom genera Amphora, Halamphora, Cymbella, Cymbopleura, Delicatophycus, Encyonema, Encyonopsis, Reimeria, Gomphonema, Gomphosphenia, Gomphonella, Gomphosinica, and Gomphoneis. A total of 207 samples of surface sediment and periphyton collected from 106 wetland, high-energy, embayment, and deeper nearshore locales are represented. Light micrographs of 154 taxa are presented. Of these, 76 could not be fully identified as known taxa from the existing literature and so are given tentative names, numbers or conferred assignments. Lake and habitat specificity, modeled autecological optima for phosphorus and chloride, and tolerance to anthropogenic stressors are described for 39 of the more common taxa.

Asymmetric strategy for enhanced performance of flexible electroadhesive clutch

Flexible electroadhesive clutches with high shear stress and fast response working at low voltage are much desired in wearable electronics and robotic systems. Dielectric materials with opposite charge characteristics could maximize the clutch performance by taking advantages of the boosted electroadhesion between the two contact pads in an asymmetrically structured clutch. In this paper, asymmetrically structured electroadhesive clutches are proposed and reported for the first time. The asymmetric structured clutch exhibits a two-fold increment in the shear force but similar response time by simply reversing the electrode polarity. This work provides a new dimension to realize high-performance electroadhesive clutches based on an asymmetric strategy.

Cobalt-Catalyzed Enantioselective Hydroamination of Arylalkenes with Secondary Amines

Catalytic asymmetric hydroamination of alkenes with Lewis basic amines is of great interest but remains a challenge in synthetic chemistry. Here, we developed a Co-catalyzed asymmetric hydroamination of arylalkenes directly using commercially accessible secondary amines. This process enables the efficient access to valuable α-chiral tertiary amines in good to excellent yields and enantioselectivities. Mechanistic studies suggest that the reaction includes a CoH-mediated hydrogen atom transfer (MHAT) with arylalkenes, followed by a pivotal catalyst controlled S_N 2-like pathway between in situ generated electrophilic cationic alkylcobalt(IV) species and free amines. This radical-polar crossover strategy not only provides a straightforward and alternative approach for the synthesis of enantioenriched α-tertiary amines, but also underpins the substantial opportunities in developing asymmetric radical functionalization of alkenes with various free nucleophiles in oxidative MHAT catalysis.

Stacked dilated convolutions and asymmetric architecture for U-Net-based medical image segmentation

Deep learning has been widely utilized for medical image segmentation. The most commonly used U-Net and its variants often share two common characteristics but lack solid evidence for the effectiveness. First, each block (i.e., consecutive convolutions of feature maps of the same resolution) outputs feature maps from the last convolution, limiting the variety of the receptive fields. Second, the network has a symmetric structure where the encoder and the decoder paths have similar numbers of channels. We explored two novel revisions: a stacked dilated operation that outputs feature maps from multi-scale receptive fields to replace the consecutive convolutions; an asymmetric architecture with fewer channels in the decoder path. Two novel models were developed: U-Net using the stacked dilated operation (SDU-Net) and asymmetric SDU-Net (ASDU-Net). We used both publicly available and private datasets to assess the efficacy of the proposed models. Extensive experiments confirmed SDU-Net outperformed or achieved performance similar to the state-of-the-art while using fewer parameters (40% of U-Net). ASDU-Net further reduced the model parameters to 20% of U-Net with performance comparable to SDU-Net. In conclusion, the stacked dilated operation and the asymmetric structure are promising for improving the performance of U-Net and its variants.

The impact of fiscal decentralization, green energy, and economic policy uncertainty on sustainable environment: a new perspective from ecological footprint in five OECD countries

The paper explores the short-run and long-run asymmetric impact of fiscal decentralization, green energy, and economic policy uncertainty on environmental sustainability proxied by ecological footprint. Using the Nonlinear Autoregressive Distributed lag (NARDL) approach in selected five OECD countries, we find that ecological footprint responds to positive and negative fiscal decentralization asymmetrically in the long run and short run. However, the nature of the response varies significantly across countries. The result also suggests that green energy is a major factor in reducing the ecological footprint in all countries except Canada. Finally, economic policy uncertainty plays a negative and significant role in the ecological footprint in the UK, USA, and Germany while insignificant in Australia and Canada. Implications for effective environmental policies are discussed.

Bilateral simultaneous asymmetric hip fracture without major trauma in an elderly patient: a case report

BACKGROUND

Simultaneous bilateral hip fractures without major trauma in the elderly are rare and usually symmetrical. To the best of our knowledge, only two cases of bilateral simultaneous asymmetric hip fracture in the elderly without major trauma have been reported.

CASE PRESENTATION

We present the case of a 90-year-old Japanese man with simultaneous bilateral asymmetric hip fractures with trochanteric fracture on the right side and greater trochanteric fracture on the left side. He complained of dyspnea at midnight and was referred to our emergency department. He was admitted to the internal medicine department for bacterial pneumonia treatment. On the 8th day of hospitalization, he was referred to our orthopedic surgery department for hip pain and was found to have fractures of both hips. Computed tomography findings showed that the left femoral neck fracture was an old fracture, while the left greater trochanteric fracture and the right trochanteric fracture were fresh fractures. He was surgically treated through open reduction and internal fixation with an intramedullary nail on the right and hemiarthroplasty on the left in supine position, performed during the same surgical sessions on the 12th day of hospitalization.

CONCLUSIONS

We report a new form of simultaneous bilateral asymmetric hip fracture in the elderly. The fracture types of the case were femoral trochanteric fracture and greater trochanteric fracture of the femur, which were different from the fracture types in the previously reported two cases. Clinicians should be aware of the possibility of simultaneous bilateral hip fractures, especially in the elderly.

Numerical simulations of the nonsymmetric growth and remodeling of arteries under axial twisting

Blood vessels are often subjected to axial twisting during body movement or surgery. Sustained twisting may lead to blood vessel growth and remodeling, however, it remains unclear how the extracellular matrix in the blood vessels remodel under sustained axial twisting. This study aimed to develop a computational model to simulate stress-induced growth and remodeling (G&R) of thin-walled blood vessels under axial twisting. Cylindrical vessels were subjected to a step increase in axial torque while the axial stretch and lumen pressure remained constant. The vessel walls were modeled based on the constrained mixture theory given as microstructure-based discrete fiber families with isotropic matrix structure models. Simulation results demonstrated that in response to a constant twist angle loading, arterial wall thickness, mass, and twisting torque gradually increase towards a new steady state. However, the stress and mass decrease in one diagonal fiber family while increasing in the other diagonal fiber family before reaching plateaus. A novel finding was that the two helical collagen fiber families showed different growth rates and patterns during remodeling, driven by the different fiber stresses generated by the twisting, and led to non-symmetric material properties. This study sheds new light on arterial wall remodeling under axial twisting.

Dynamic linkages between non-renewable energy, renewable energy and economic growth through nonlinear ARDL approach: evidence from Malaysia

The purpose of this paper is to investigate the links between renewable energy (RE), non-renewable energy (NRE), capital, labour and economic growth, using the nonlinear autoregressive distributive lag (NARDL) model in Malaysia for the period of 1980-2018. The results of NARDL confirm the asymmetric effect of RE and NRE consumption on the economic growth in the long run as well as the short run in Malaysia. The findings also show that in the long and short run, positive shocks of NRE are greater than the positive shocks of RE. It indicates that Malaysia's economic growth is highly dependent on NRE which is not a good indication as NRE consumption increases carbon dioxide (CO2) emission in the country. Moreover, the empirical results of this study demonstrated that RE consumption reduction accelerates economic growth, whereas NRE consumption reduction decreases economic growth. It can have claimed that in Malaysia, RE is still more expensive than NRE. In conclusion, this study offered a variety of measures to develop RE to reduce the dependency on NRE consumption.

Cobalt-Catalyzed Asymmetric Alkylation of (Hetero)Arenes with Styrenes

An efficient and general intermolecular Cobalt(II)-catalyzed asymmetric alkylation of styrenes with (hetero)arenes including indoles, thiophene and electron rich arenes has been developed, providing straightforward access to enantioenriched alkyl(hetero)arenes with high enantioselectivity. Mechanistic studies suggest that the reaction underwent a CoH-mediated hydrogen atom transfer (HAT) with alkenes, followed by a pivotal catalyst-controlled S_N 2-like pathway between in situ generated organocobalt(IV) species and aromatic nucleophiles. This is the first CoH-catalyzed asymmetric hydrofunctionalization using carbon nucleophiles, providing a new strategy for asymmetric Friedel-Crafts type alkylation.

A Biomechanical Comparison of Gliding Resistance between Modified Lim Tsai and Asymmetric Tendon Repair Techniques in Zone II Flexor Tendon Repairs

Background: Early active motion protocols have shown better functional outcomes in zone II flexor tendon lacerations. Different techniques of tendon repair have different effects on gliding resistance, which can impact tendon excursion and adhesion formation. For successful initiation of early active mobilisation, the repair technique should have high breaking strength and low gliding resistance. Previous studies have shown the Modified Lim-Tsai technique demonstrates these characteristics. The Asymmetric repair has also shown superior ultimate tensile strength. This study aims to compare the gliding resistance between the two techniques. Methods: FDP tendons from ten fresh frozen cadaveric fingers were randomly divided into two groups, transected completely distal to the sheath of the A2 pulley and repaired using either the Modified Lim-Tsai or Asymmetric technique. The core repair was performed with Supramid 4-0 looped sutures and circumferential epitendinous sutures were done with nylon monofilament Prolene 6-0 sutures. The gliding resistance and ultimate tensile strength were then tested. Results: The gliding resistance of the Asymmetric and Modified Lim-Tsai repair techniques were 0.2 and 0.95 N respectively. This difference was significant (p = 0.008). The Modified Lim-Tsai technique had a higher ultimate tensile strength and load to 2 mm gap formation, though this was not significant. Conclusions: Gliding resistance of the Asymmetric repair is significantly less than that of Modified Lim-Tsai. Ultimate tensile strength and load to 2 mm gap formation are comparable.

The asymmetric and multi-scale volatility correlation between global oil price and economic policy uncertainty of China

With the monthly data of WTI oil price and economic policy uncertainty (EPU) of China from January 2000 to August 2020, this paper detailedly investigates the asymmetric volatility correlations between two types of EPU of China and global oil price in different time scales. The empirical results demonstrate that the volatility correlation between EPU of China and West Texas Intermediate (WTI) oil price is mainly reflected in the monetary policy uncertainty (MPU), while that of fiscal policy uncertainty (FPU) is much weaker. Specifically speaking, the volatility correlation between MPU of China and downward WTI oil price is significantly negative in the short-middle term (4-8 months) and changes to positive in the middle-long term (8-16 months), while that of upward WTI oil price is only significantly positive in the long term (16-32 months). Our findings provide a deeper understanding of the oil price-EPU correlation in China, and can be valuable guidance for diversified market participants such as government policy-makers and global investors.

Neonatal hypoglycaemia and body proportionality in small for gestational age newborns: a retrospective cohort study

Small for gestational age (SGA) newborns are at risk of developing neonatal hypoglycaemia. SGA newborns comprise a heterogeneous group including both constitutionally small and pathologically growth restricted newborns. The process of fetal growth restriction may result in brain sparing at the expense of the rest of the body, resulting in disproportionally small newborns. The aim of this study was to discover whether body proportionality influences the risk of developing neonatal hypoglycaemia in SGA newborns. A retrospective cohort study was performed in 402 newborns who were SGA without additional risk factors for hypoglycaemia. Body proportionality was classified in two ways: (1) using symmetric (sSGA) or asymmetric (aSGA), defined as head circumference (HC) below or above the 10th percentile, respectively; (2) using cephalization index (HC/birth weight), standardized for gestational age. Hypoglycaemia was observed in 50% of aSGA and 40.9% of sSGA newborns (P-value 0.12). Standardized CI in newborns with hypoglycaemia was higher compared to newborns without hypoglycaemia (median 1.27 (1.21-1.35) versus 1.24 (1.20-1.29); (P 0.002)). Multivariate logistic regression analyses showed both CI and standardized CI to be associated with the occurrence of hypoglycaemia (OR 1.48 (1.24-1.77) and OR 1.44 (1.13-1.83), respectively). The majority of hypoglycaemic events (96.1%) occurred in the first 6 h after birth.   Conclusion: Body proportionality might be of influence, depending on the classification used. Larger prospective studies with a clear consensus definition of body proportionality are needed. What is Known: • Neonatal hypoglycaemia is an important complication in newborns. • Small for gestational age (SGA) newborns are more vulnerable to hypoglycaemia. What is New: • Higher incidence of hypoglycaemia was not observed in asymmetric SGA compared to symmetric SGA, but standardized cephalization index was associated with increased likelihood of hypoglycaemia. • Consensus-based definitions of body proportionality in newborns are needed.

Numerical investigation on the stability of human upper cervical spine (C1-C3)

BACKGROUND

The finite element method (FEM) is an efficient and powerful tool for studying human spine biomechanics.

OBJECTIVE

In this study, a detailed asymmetric three-dimensional (3D) finite element (FE) model of the upper cervical spine was developed from the computed tomography (CT) scan data to analyze the effect of ligaments and facet joints on the stability of the upper cervical spine.

METHODS

A 3D FE model was validated against data obtained from previously published works, which were performed in vitro and FE analysis of vertebrae under three types of loads, i.e. flexion/extension, axial rotation, and lateral bending.

RESULTS

The results show that the range of motion of segment C1-C2 is more flexible than that of segment C2-C3. Moreover, the results from the FE model were used to compute stresses on the ligaments and facet joints of the upper cervical spine during physiological moments.

CONCLUSION

The anterior longitudinal ligaments (ALL) and interspinous ligaments (ISL) are found to be the most active ligaments, and the maximum stress distribution is appear on the vertebra C3 superior facet surface under both extension and flexion moments.

Phase transited asymmetric membrane floating nanoparticles: a means for better management of poorly water-soluble drugs

PURPOSE

Effective remedy to gastrointestinal (GI) side effects caused by poorly water-soluble drugs remains a challenge. Researching for novel techniques to reduce these side effects and increase patient adherence to medical treatment is of interest. The current study aims to develop an innovative nano-sized gastro-retentive drug delivery for better management of poorly water-soluble drugs.

METHOD

A non-disintegrating ibuprofen-asymmetric membrane floating nanoparticle (Ibuprofen-AMFNP) was prepared by phase inversion technique to increase the gastric residence of the drug. Powder characterization, solubility, in vitro buoyancy, effect on in vivo inflammatory markers, and polymer diffusibility studies were conducted on the prepared formulation. All UV-spectrophotometric analysis was accomplished through a fiber optic system.

RESULTS

The prepared Ibuprofen-AMFNPs were in the nano range of 114.45 nm ±1.31 nm. The formulation was buoyant for 12 h in the dissolution media indicating increased gastric residence, had better solubility and powder characteristics compared to the pure drug. Scanning electron microscopy revealed an outer non-porous and inner porous asymmetric membrane. Ibuprofen-AMFNP followed Higuchi drug release kinetics (p=0.9925) and had a Fickian diffusion release mechanism (n=0.05). Polymer diffusibility study showed that the 24 h stored formulation had faster drug release with no lag time (-923.08 nm/h) compared to a fresh formulation (2526.32 nm/h). The prepared nano-formulation showed a higher percentage of anti-inflammatory (85.144%) effect compared to the pure drug (78.336%).

CONCLUSION

Ibuprofen-AMFNP is envisioned to help reduce drug-related GI side effects, improve drug delivery, and thereby increase patient adherence to medical treatment.

Efficacy of progressive thickness intrastromal corneal ring segments in the treatment of duck phenotype keratoconus

PURPOSE

To evaluate clinical outcomes in patients with asymmetric duck phenotype keratoconus implanted with asymmetric progressive thickness intrastromal corneal ring segments (PT-ICRS, Keraring AS, Mediphacos, Belo Horizonte, Brazil), and to demonstrate improved visual acuity and symmetry in corneal flattening.

METHODS

This single-center, retrospective, observational study evaluated the clinical outcomes at 1, 3, and 6 months after implantation of PT-ICRS in patients with duck phenotype keratoconus. After creating the intrastromal tunnel with a femtosecond laser, one 160-degree arc length PT-ICRS, either 150/250 µm or 200/300 µm, was implanted. Changes in uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction (MR), manifest refraction spherical equivalent (MRSE), mean keratometry (Kmean), maximum keratometry (Kmax), Coma@5mm, and manifest and topographical astigmatism were documented.

RESULTS

The study cohort included 23 eyes of 17 patients with a mean age of 24.6 years. From baseline to 6 months following implantation, mean UDVA improved from 0.70 logarithm of the minimum angle of resolution (logMAR) (20/100 Snellen) to 0.22 logMAR (20/33 Snellen), CDVA improved from 0.33 logMAR (20/42 Snellen) to 0.14 logMAR (20/27 Snellen), the mean sphere and MRSE decreased from -1.05 diopters (D) and -2.70 D to -0.25 D and -0.80 D, respectively, and the Kmean and Kmax improved from 46.5 D and 53.7 D to 44.6 D and 48.7 D, respectively.

CONCLUSIONS

The Keraring AS ICRS offers a safe, effective means of improving visual acuity while reducing refractive error, mean and max keratometry, and aberrations in patients with duck phenotype keratoconus.

Comparison of the visual performance between Oculentis MF30 and Tecnis ZMB00 multifocal intraocular lenses

Background

To compare the visual performance of MF30 asymmetric refractive multifocal intraocular lenses (MIOLs) with ZMB00 all optic zone diffractive MIOLs.

Methods

This is a prospective study. Patients that underwent phacoemulsification were divided into two groups according to the type of MIOLs used: 35 patients were implanted with asymmetric refractive MIOLs and 35 patients with all optic zone diffractive MIOLs. Visual acuity (VA), refraction, defocus curves, objective optical quality, and a questionnaire evaluating quality of life were measured at 3 months postoperatively.

Results

There were no significant differences between the two groups in uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), best-corrected distance visual acuity (BCDVA), or distance-corrected near visual acuity (DCNVA). However, the uncorrected intermediate VA was 0.24±0.10 in the refractive group and 0.31±0.13 in the diffractive group (P<0.05), and the distance-corrected intermediate VA was 0.22±0.09 in the refractive group and 0.31±0.14 in the diffractive group (P<0.05). Defocus curves showed two peaks of maximum vision in both groups. However, the curve between the two peaks in the refractive group was smoother than that of the diffractive group. The modulated transfer function cut-off frequency was 22.74±12.29 c/d in the refractive group and 30.50±10.04 c/d in the diffractive group (P<0.05). The Optical Quality Analysis System (OQAS) values 100% (OV100%) was 0.75±0.41 in the refractive group and 1.02±0.34 in the diffractive group (P<0.05), while the OV20% was 0.52±0.34 in the refractive group and 0.71±0.25 in the diffractive group (P<0.05). There was no significant difference between the two groups in overall satisfaction, spectacle independence ratio, or visual interference phenomenon.

Conclusions

Both MIOLs achieve good VA at distance and near vision. Oculentis MF30 showed better intermediate VA, and Tecnis ZMB00 appears to have better objective visual quality.

Trial registration

NCT02234635 (http://www.clinicaltrials.gov).

Asymmetry indicates more severe and active disease in Graves' orbitopathy: results from a prospective cross-sectional multicentre study

PURPOSE

Patients with Graves' orbitopathy can present with asymmetric disease. The aim of this study was to identify clinical characteristics that distinguish asymmetric from unilateral and symmetric Graves' orbitopathy.

METHODS

This was a multi-centre study of new referrals to 13 European Group on Graves' Orbitopathy (EUGOGO) tertiary centres. New patients presenting over a 4 month period with a diagnosis of Graves' orbitopathy were included. Patient demographics were collected and a clinical examination was performed based on a previously published protocol. Patients were categorized as having asymmetric, symmetric, and unilateral Graves' orbitopathy. The distribution of clinical characteristics among the three groups was documented.

RESULTS

The asymmetric group (n = 83), was older than the symmetric (n = 157) group [mean age 50.9 years (SD 13.9) vs 45.8 (SD 13.5), p = 0.019], had a lower female to male ratio than the symmetric and unilateral (n = 29) groups (1.6 vs 5.0 vs 8.7, p < 0.001), had more active disease than the symmetric and unilateral groups [mean linical Activity Score 3.0 (SD 1.6) vs 1.7 (SD 1.7), p < 0.001 vs 1.3 (SD 1.4), p < 0.001] and significantly more severe disease than the symmetric and unilateral groups, as measured by the Total Eye Score [mean 8.8 (SD 6.6) vs 5.3 (SD 4.4), p < 0.001, vs 2.7 (SD 2.1), p < 0.001].

CONCLUSION

Older age, lower female to male ratio, more severe, and more active disease cluster around asymmetric Graves' orbitopathy. Asymmetry appears to be a marker of more severe and more active disease than other presentations. This simple clinical parameter present at first presentation to tertiary centres may be valuable to clinicians who manage such patients.

The impact of oil and gold price fluctuations on the South African equity market: Volatility spillovers and financial policy implications

This paper assesses the impact of gold and oil price fluctuations on the volatility of the South African stock market and its component indices or sectors - namely, the financial, industrial and resource sectors - to infer the link between the commodity and stock markets in South Africa. Use is made of the vector autoregressive asymmetric dynamic conditional correlation generalised autoregressive conditional heteroskedasticity (VAR-ADCC-GARCH) model to this end. Moreover, the paper assesses the magnitude of the optimal portfolio weight, hedge ratio and hedge effectiveness for portfolios constituted of a pair of assets, namely oil-stock and gold-stock pairs. The findings of the study show that there is significant volatility spillover between the gold and stock markets, and the oil and stock markets. This finding suggests the importance of the link between the commodity and stock markets, which is essential for portfolio management. With reference to portfolio optimization and the possibility of hedging when using the pairs of assets under study, the findings suggest the importance of combining gold and stocks as the best strategy to hedge against stocks risk, especially during financial crises.

The asymmetric relationship between globalization, tourism, CO2 emissions, and economic growth in Turkey: implications for environmental policy making

The current study examines the importance of asymmetric modelling of tourism-CO₂ emissions relationship by incorporating real income per capita and the newly developed globalization index in a multivariate time series model between 1970 and 2014 for Turkey. We used a non-linear autoregressive distributed lag model in analyzing the asymmetric cointegration association between the selected variables. Using Hatemi-J (2012) asymmetric causality testing method, we examined the asymmetric causal relationship among the variables. The empirical outcomes provide evidence for the existence of asymmetric long-run cointegration nexus among the variables. Asymmetric causality results show that both the positive and negative shock of tourism influence the CO₂ emissions in the long-term, while in the short-term, only the negative shock of tourism contributes to CO₂ emissions. Also discussed are the policy implications with regard to Turkey's environmental and economic policies.

Mathematical assessment of the spermatozoa transport through couple stress fluid in an asymmetric human cervical canal

Swimming of spermatozoa through couple stress fluid in an asymmetric human cervical canal is investigated in the present theoretical analysis. A couple of fourth-order partial differential equations arising from the mathematical modelling of the proposed model is solved analytically. Flow variables like pressure gradient, propulsive velocity, mucus velocity and time mean flow rate are analysed for the pertinent parameters. Conspicuous features of the pumping characteristics are explored. It is found that pressure rise facilitates the motion of spermatozoa to fertilize an ovum in the female reproductive tract, whereas pressure drop by inverting the direction of spermatozoa controls the probability of pregnancy. Maximal propulsive velocity of the spermatozoa is reported in the absence of travelling waves along the cervical walls. Minute impact of phase difference on propulsive velocity is evident. An analogy of the current analysis with the existing literature is also made.

The costochondral length in patients with pectus excavatum is longer than that of the normal thorax

PURPOSE

Recently, several investigators reported that costal cartilage does not overgrow in pectus excavatum (PE). We wished to clarify whether costochondral length is longer in PE than the normal thorax and we tried to clarify the change of the shape of precordial concavity according to the growth in PE.

METHODS

We evaluated 243 CT axial images of patients with PE and 246 CT axial images of patients without thoracic deformity. We divided the fifth costal cartilage into several lengths. We considered each part to be a straight line and calculated the length of the lines. We compared the approximate costochondral length between PE and normal thorax. We analyzed the distance between both anterior tips of fifth rib, and the ratio of the width and the depth of concavity to thoracic diameter in PE.

CONCLUSIONS

The costochondral length in patients with PE is highly likely to be longer than that of the normal thorax. The length of costal cartilage may be longer in asymmetric PE than symmetric PE. It may start in infantile period in PE that the thoracic shape turns into asymmetry from symmetry. The precordial concavity of PE may be shaped by overgrowth of both costal cartilages and ribs.

Regio- and Stereoselective Rhodium(II)-Catalyzed C-H Functionalization of Cyclobutanes

Recent developments in controlled C-H functionalization transformations continue to inspire new retrosynthetic disconnections. One tactic in C-H functionalization is the intermolecular C-H insertion reaction of rhodium bound carbenes. These intermediates can undergo highly selective transformations through the modulation of the ligand framework of the rhodium catalyst. This work describes our continued efforts towards differentiating C-H bonds in the same molecule by judicious catalyst choice. Substituted cyclobutanes which exist as a mixture of interconverting conformers and possess neighboring C-H bonds within a highly strained framework are the targets herein for challenging the current suite of catalysts. While most C-H functionalization tactics focus on generating 1,2-disubstituted cyclobutanes via substrate-controlled directing group methods, the regiodivergent methods in this paper provide access to chiral 1,1-disubstituted and cis-1,3-disubstituted cyclobutanes simply by changing the catalyst identity, thus permitting entry to novel chemical space.

Wyburn-Mason syndrome presenting with bilateral retinal racemose hemangioma with unilateral serous retinal detachment

Wyburn-Mason syndrome is associated with unilateral retinal racemose hemangioma. Rarely, it presents with bilateral and symmetrical grade of malformation. We describe a 37-year old male, who presented with Wyburn-Mason syndrome presenting with bilateral but asymmetrical retinal hemangioma. The eye with advanced grade of hemangioma was complicated with exudation, intraretinal fluid, neurosensory detachment, and reduced vision. He was treated with one intravitreal injection of bevacizumab, after which both the intraretinal fluid and neurosensory detachment resolved. His vision improved and was maintained till 1 year of follow-up.

The asymmetric effect of regulatory fit on moral judgments of other-oriented lies

We examined whether regulatory fit effects are asymmetric-namely, whether they occur only among individuals with a promotion focus or a prevention focus. We adopted a task where individuals make moral judgments of other-oriented lies and conducted three studies. The results indicated that prevention-focused individuals judged other-oriented lies based on a vigilant strategy as more moral than lies based on an eager strategy (Studies 1 and 2). Meanwhile for promotion-focused individuals, there were no differences between eager and vigilant strategies on moral judgments of other-oriented lies. Additionally, the results suggested that the feeling of rightness is an underlying mechanism of the regulatory fit effects of prevention focus (Study 3).

Fe3O4 nanospheres in situ decorated graphene as high-performance anode for asymmetric supercapacitor with impressive energy density

Unique nanostructure, high electrical conductivity, satisfactory energy density, and extraordinary cycling stability are important evaluation criteria for high-efficient energy storage devices. Herein, Fe₃O₄ nanospheres are successfully in situ decorated on graphene nanosheets through an environmentally benign and facile solvothermal procedure. When utilized as an electrode for supercapacitor, the graphene/Fe₃O₄ nanocomposite exhibits a notably enhanced specific capacity (268 F·g^-1 at 2 mV·s^-1) and remarkable cycling performance with 98.9% capacity retention after 10,000 cycles. Furthermore, the fabricated graphene/MnO₂//graphene/Fe₃O₄ asymmetric supercapacitor device displays a desirable energy density (87.6 Wh·kg^-1) and superior cycling stability (93.1% capacity retention after 10,000 cycles).

Asymmetric bilateral traumatic hip dislocation: A case report

INTRODUCTION

Traumatic hip dislocation is a severe injury with the potential for significant morbidity and mortality. Bilateral hip dislocation is rare representing 1.25% of all hip dislocations.

PRESENTATION OF THE CASE

A 19-year-old male had a high-speed motor vehicle accident. After stabilizing the patient, it was noticed that the position of the right lower limb was in adduction and internal rotation while the left was in external rotation and abduction. Pelvis x-ray showed right superior posterior and left anterior inferior hip dislocations. Closed reduction was performed within 3 hours from the trauma for both sides. The post reduction CT scan showed adequate reduction of both hips with no associated fractures. During his three-year follow-up, he never had any complaints and the clinical examination and radiographs did not reveal any abnormalities.

DISCUSSION

Early reduction of hip dislocations minimizes the risk of osteonecrosis of the femoral head. The current recommendations state that a hip dislocation must be reduced within 6 hours.

CONCLUSION

This is a rare case of bilateral asymmetric hip dislocations with no concomitant fractures. It is important to reduce hip dislocation within 6 hours from the time of injury to prevent osteonecrosis of the femoral head.

A small molecular electron acceptor based on asymmetric hexacyclic core of thieno[1,2-b]indaceno[5,6-b']thienothiophene for efficient fullerene-free polymer solar cells

A novel A-D-A (acceptor-donor-acceptor) type non-fullerene small molecule, A201, consisting of an asymmetric thieno[1,2-b]indaceno[5,6-b']thienothiophene (TITT) unit as middle D part and 2-(3-oxo-2,3-dihydroinden-1-ylidene) malononitrile (IC) groups as end-capped A parts was designed and synthesized. The asymmetric TITT building block showed a higher dipole moment of 0.85 Debye (1 Debye = 3.33564 × 10^-30 cm) compared with the symmetric analogues of indacenodithiophene (IDT) and indacenodithieno[3,2-b]thiophene (IDTT) of 0.098 and 0.13 Debye, respectively. The solution-processed bulk heterojunction solar cells using a benzotriazole (BTA)-based polymer of J71 as donor and A201 as acceptor, showed a power conversion efficiency (PCE) of 9.36% with an open-circuit voltage (V_oc) of 0.88 V, a short-circuit current (J_sc) of 13.15 mA cm^-2, and a fill factor (FF) of 0.67, under the illumination of AM 1.5G at 100 mW cm^-2. The high PCE of this material combination could be attributed to its broad absorption spectrum and the high hole mobility (μ_h) and electron mobility (μ_e) of 9.56 × 10^-4 and 5.17 × 10^-4 cm² V^-1 s^-1, respectively. These results indicate that the asymmetric electron-donating segments are promising to construct A-D-A type small molecular acceptors, which could largely enhance the diversity of building blocks to design photovoltaic materials.

Sleeping Beauty transposon integrates into non-TA dinucleotides

Background

Sleeping Beauty transposon (SB) has become an increasingly important genetic tool for generating mutations in vertebrate cells. It is widely thought that SB exclusively integrates into TA dinucleotides. However, this strict TA-preference has not been rigorously tested in large numbers of insertion sites that now can be detected with next generation sequencing. Li et al. found 71 SB insertions in non-TA dinucleotides in 2013, suggesting that TA dinucleotides are not the only sites of SB integration, yet further studies on this topic have not been carried out.

Results

In this study, we re-analyzed 600 million pairs of Illumina sequence reads from a high-throughput SB mutagenesis screen and identified 28 thousand SB insertions in non-TA sites. We recovered some of these non-TA sites using PCR and confirmed that at least a subset of the insertions at non-TA sites are real integrations. The consensus sequence of these non-TA sites shows an asymmetric pattern distinct from the symmetric pattern of the canonical TA sites. Perfect similarity between the downstream flanking sequence and SB transposon ends indicates there may be interaction between the transposon DNA binding domain of transposase and the target DNA.

Conclusion

The TA-preference of SB transposon is not as strict as what people had thought. And the SB integrations at non-TA sites might be guided by the interaction between the transposon DNA binding domain of SB transposase and the target DNA.

Electronic supplementary material

The online version of this article (10.1186/s13100-018-0113-8) contains supplementary material, which is available to authorized users.

Utility of routine urine CMV PCR and total serum IgM testing of small for gestational age infants: a single center review

BACKGROUND

Due to the extremely low incidence of TORCH (toxoplasmosis, rubella, CMV, herpes simplex virus) infections, diagnostic testing of all small for gestational age (SGA) infants aimed at TORCH etiologies may incur unnecessary tests and cost.

OBJECTIVE

To determine the frequency of urine CMV PCR and total IgM testing among infants with birth weight <10% and the rate of test positivity. To evaluate the frequency of alternative etiologies of SGA in tested infants.

METHODS

Retrospective chart review of SGA infants admitted to the neonatal intensive care unit (NICU) at NYU Langone Medical Center between 2007 and 2012. Subjects were classified as being SGA with or without intrauterine growth restriction (IUGR). The IUGR subjects were then further categorized as having either symmetric or asymmetric IUGR utilizing the Fenton growth chart at birth. Initial testing for TORCH infections, which included serum total IgM, CMV PCR and head ultrasound, were reviewed and analyzed.

RESULTS

Three hundred and eighty-six (13%) infants from a total of 2953 NICU admissions had a birth weight ≤10th percentile. Of these, 44% were IUGR; 34% being symmetric IUGR and 10% asymmetric. A total of 32% of SGA infants had urine CMV PCR and total IgM tested with no positive results. As expected, significantly higher percentage of symmetric IUGR infants were tested compared to asymmetric IUGR and non-IUGR SGA infants, (64% vs. 47% vs. 19%) P≤0.01. However, 63% of infants with a known cause for IUGR had same testing done aimed at TORCH infections. We calculated additional charges of $64,065 that were incurred by such testing.

CONCLUSIONS

The majority of infants in our study who received testing for urine CMV PCR and total IgM aimed at TORCH infections had one or more other known non-infectious etiologies for IUGR. Because the overall yield of such testing is extremely low, we suggest tests for possible TORCH infections may be limited to symmetric IUGR infants without other known etiologies. Improved guidelines testing for TORCH infections can result in reducing hospital charges and unnecessary studies.

Pronounced Photovoltaic Response from Multi-layered MoTe2 Phototransistor with Asymmetric Contact Form

In this study, we fabricate air-stable p-type multi-layered MoTe₂ phototransistor using Au as electrodes, which shows pronounced photovoltaic response in off-state with asymmetric contact form. By analyzing the spatially resolved photoresponse using scanning photocurrent microscopy, we found that the potential steps are formed in the vicinity of the electrodes/MoTe₂ interface due to the doping of the MoTe₂ by the metal contacts. The potential step dominates the separation of photoexcited electron-hole pairs in short-circuit condition or with small V _sd biased. Based on these findings, we infer that the asymmetric contact cross-section between MoTe₂-source and MoTe₂-drain electrodes is the reason to form non-zero net current and photovoltaic response. Furthermore, MoTe₂ phototransistor shows a faster response in short-circuit condition than that with higher biased V _sd within sub-millisecond, and its spectral range can be extended to the infrared end of 1550 nm.

Highly Stereoselective Asymmetric Aldol Routes to tert-Butyl-2-(3,5-difluorophenyl)-1-oxiran-2-yl)ethyl)carbamates: Building Blocks for Novel Protease Inhibitors

Enantioselective syntheses of tert-butyl ((S)-2-(3,5-difluorophenyl)-1-((S)-oxiran-2-yl)ethyl)carbamate and ((S)-2-(3,5-difluorophenyl)-1-((R)-oxiran-2-yl)ethyl)carbamate are described. We utilized asymmetric syn- and anti-aldol reactions to set both stereogenic centers. We investigated ester-derived Ti-enolate aldol reactions as well as Evans' diastereoselective syn-aldol reaction for these syntheses. We have converted optically active ((S)-2-(3,5-difluorophenyl)-1-((S)-oxiran-2-yl)ethyl)carbamate to a potent β-secretase inhibitor.

Synthesis, characterization, and nonlinear optical (NLO) properties of truxene-cored diphenylamine derivatives

Three star-shaped compounds based on a truxene core (FS11, FS12 and FS13) were prepared. The truxene core is incorporating with asymmetric diphenylamines, including one phenyl of diphenylamine substituted by methoxy group and the other phenyl substituted by tolyl, fluorophenyl and phenylethynyl for FS11, FS12 and FS13, respectively. Their one-photon, two-photon absorption, geometric structures, electrochemical behavior and thermal properties were investigated. The absorption maxima of charge transfer band for FS11, FS12 and FS13 are 375nm, 373nm and 383nm, and the corresponding molar extinction coefficients of FS11, FS12 and FS13 is 79,950M^-1cm^-1, 67,220M^-1cm^-1 and 108,780M^-1cm^-1. The "pull-push" structure promotes charge transfer between asymmetric diphenylamine branches and the truxene core. Their two-photon absorbtion property is measured by two-photon induced fluorescence. The maximum two-photon cross-sections values of FS11, FS12 and FS13 are excited at 750nm, which are 260 GM, 204GM and 367 GM, respectively.

Does the tibia component design affect the need for offset stems in revision total knee arthroplasty?

INTRODUCTION

The stem/keel location varies between anatomic and symmetric revision tibial baseplates. The current study investigates the impact of an anatomic versus symmetric stem location on the need for offset couplers in revision total knee arthroplasty.

MATERIALS AND METHODS

Hip to ankle standing radiographs and lateral radiographs of 75 patients were analyzed using digital templating software. The offset in the anterior-posterior as well as medial-lateral plane between the center of the tibial diaphysis and the stem of the tibial baseplate were determined for an anatomic and symmetric tibial baseplate, respectively. Measurements were repeated for 4 resection levels: tip of fibular head (0), 10 mm (1), 15 mm (2) and 20 mm (3) below the tip of the fibula head.

RESULTS

Anatomic tibial baseplates require less offset for resection levels up to the tip of the fibula: total offset 2.28 versus 5.44 mm (p < 0.001). However, for defects that result in resection levels below the tip of the fibula symmetric tibial baseplates require less offset: resection level 1: 3.18 versus 2.4 mm (p = 0.008), 2: 4.81 versus 1.67 mm (p < 0.001) and resection level 3: 5.66 versus 1.52 mm (P < 0.001).

CONCLUSION

The current study suggests that while asymmetric anatomic tibial baseplates have benefits for revisions with minimal bone loss, symmetric tibial baseplates require less offset when larger bone defects are encountered.

Clinical characteristics in patients with asymmetric idiopathic pulmonary fibrosis

BACKGROUND

A group of patients with idiopathic pulmonary fibrosis (IPF) presents with disease affecting one lung markedly more than the other. At this time, it is unclear how this population differs from those who present with more symmetric disease. We sought to explain the characteristics of the asymmetric group and how their disease progresses.

METHODS

In this retrospective case-control study we accessed an interstitial lung disease (ILD) database and identified 14 asymmetric IPF cases via high-resolution computed tomography (HRCT) scoring of each lung lobe's disease severity. We identified 28 symmetric IPF controls from the same database using the same methods, and compared the clinical features of each group.

RESULTS

Patients with asymmetric disease exhibited similar demographics as those in the general IPF population; they were predominantly male (64%), elderly (69 years old), and used tobacco (57%). We found a trend toward significantly increased all-cause mortality in the case population two years following diagnosis (p = 0.089). Pulmonary function tests were significantly lower in the case group at the time of diagnosis, then both groups experienced gradual decline. We found no statistically significant differences in number of IPF exacerbations (cases 43%, controls 39%, p = 0.824) and gastro-esophageal reflux (both groups 50%).

CONCLUSION

Patients with asymmetric IPF resemble patients in the general IPF population but may have a lower overall survival rate. Further systemic factors may be studied to identify reasons for disease asymmetry and clinical decline in this population.

DISMISS: detection of stranded methylation in MeDIP-Seq data

Background

DNA methylation is an important regulator of gene expression and chromatin structure. Methylated DNA immunoprecipitation sequencing (MeDIP-Seq) is commonly used to identify regions of DNA methylation in eukaryotic genomes. Within MeDIP-Seq libraries, methylated cytosines can be found in both double-stranded (symmetric) and single-stranded (asymmetric) genomic contexts. While symmetric CG methylation has been relatively well-studied, asymmetric methylation in any dinucleotide context has received less attention. Importantly, no currently available software for processing MeDIP-Seq reads is able to resolve these strand-specific DNA methylation signals. Here we introduce DISMISS, a new software package that detects strand-associated DNA methylation from existing MeDIP-Seq analyses.

Results

Using MeDIP-Seq datasets derived from Apis mellifera (honeybee), an invertebrate species that contains more asymmetric- than symmetric- DNA methylation, we demonstrate that DISMISS can identify strand-specific DNA methylation signals with similar accuracy as bisulfite sequencing (BS-Seq; single nucleotide resolution methodology). Specifically, DISMISS is able to confidently predict where DNA methylation predominates (plus or minus DNA strands – asymmetric DNA methylation; plus and minus DNA stands – symmetric DNA methylation) in MeDIP-Seq datasets derived from A. mellifera samples. When compared to DNA methylation data derived from BS-Seq analysis of A. mellifera worker larva, DISMISS-mediated identification of strand-specific methylated cytosines is 80 % accurate. Furthermore, DISMISS can correctly (p <0.0001) detect the origin (sense vs antisense DNA strands) of DNA methylation at splice site junctions in A. mellifera MeDIP-Seq datasets with a precision close to BS-Seq analysis. Finally, DISMISS-mediated identification of DNA methylation signals associated with upstream, exonic, intronic and downstream genomic loci from A. mellifera MeDIP-Seq datasets outperforms MACS2 (Model-based Analysis of ChIP-Seq2; a commonly used MeDIP-Seq analysis software) and closely approaches the results achieved by BS-Seq.

Conclusions

While asymmetric DNA methylation is increasingly being found in growing numbers of eukaryotic species and is the predominant pattern observed in some invertebrate genomes, it has been difficult to detect in MeDIP-Seq datasets using existing software. DISMISS now enables more sensitive examinations of MeDIP-Seq datasets and will be especially useful for the study of genomes containing either low levels of DNA methylation or for genomes containing relatively high amounts of asymmetric methylation.

The Use of Tibial Osteotomy (Ankle Plafondplasty) for Joint Preservation of Ankle Deformity and Early Arthritis

Asymmetric ankle osteoarthritis (OA) is an increasingly recognized condition. It is imperative to differentiate between extraarticular and intraarticular deformity and to address these appropriately. Any associated instability and multilevel deformity must be recognized and addressed. Patients with intraarticular varus or valgus asymmetric OA have poorer outcomes and higher rates of recurrence when treated with standard techniques targeted at correction with traditional supramalleolar or inframalleolar techniques. Plafondplasty aims to correct the deformity at its center of rotation and angulation and is associated with low rates of recurrence, substantial postoperative pain relief, functional improvement, and a possible slowing of the degenerative process.

Asymmetric linkage disequilibrium: Tools for assessing multiallelic LD

Standard measures of linkage disequilibrium (LD) provide an incomplete description of the correlation between two loci. Recently, Thomson and Single (2014) described a new asymmetric pair of LD measures (ALD) that give a more complete description of LD. The ALD measures are symmetric and equivalent to the correlation coefficient r when both loci are bi-allelic. When the numbers of alleles at the two loci differ, the ALD measures capture this asymmetry and provide additional detail about the LD structure. In disease association studies the ALD measures are useful for identifying additional disease genes in a genetic region, by conditioning on known effects. In evolutionary genetic studies ALD measures provide insight into selection acting on individual amino acids of specific genes, or other loci in high LD (see Thomson and Single (2014) for these examples). Here we describe new software for computing and visualizing ALD. We demonstrate the utility of this software using haplotype frequency data from the National Marrow Donor Program (NMDP). This enhances our understanding of LD patterns in the NMDP data by quantifying the degree to which LD is asymmetric and also quantifies this effect for individual alleles.

Unilateral Outer Bow Expanded Cervical Headgear Force System: 3D Analysis Using Finite Element Method

OBJECTIVES

Headgears are among the effective orthodontic appliances to achieve treatment goals. Unilateral molar distal movement is sometimes needed during an orthodontic treatment, which can be achieved by an asymmetric headgear. Different unilateral headgears have been introduced. The main goal of this study was to analyze the force system of unilateral expanded outer bow asymmetric headgears by the finite element method (FEM).

MATERIALS AND METHODS

Six 3D finite element models of a mesiodistal slice of the maxilla containing upper first molars, their periodontal ligaments (PDLs), cancellous bone, cortical bone, and a cervical headgear with expanded outer bow attached to maxillary first molars were designed in SolidWorks 2010 and meshed in ANSYS Workbench ver. 12.1. The models were the same except for the degree of outer bow expansion. The outer bow ends were loaded with 2 N force. The distal driving force and the net moment were evaluated.

RESULTS

A decrease in the distalizing force in the normal side molar from 1.69 N to 1.37 N was shown by increasing the degree of unilateral expansion. At the same time, the force increased from 2.19 N to 2.49 N in the expanded side molar. A net moment increasing from 2.26 N.mm to 4.64 N.mm was also shown.

CONCLUSION

Unilateral outer bow expansion can produce different distalizing forces in molars, which increase by increasing the expansion.

Safely targeting cancer stem cells via selective catenin coactivator antagonism

Throughout our life, long-lived somatic stem cells (SSC) regenerate adult tissues both during homeostatic processes and repair after injury. The role of aberrant regulation of SSC has also recently gained prominence in the field of cancer research. Following malignant transformation, so termed cancer stem cells (CSC), endowed with the same properties as SSC (i.e. the ability to both self-renew and generate differentiated progenitors), play a major part in tumor initiation, therapy resistance and ultimately relapse. The same signaling pathways involved in regulating SSC maintenance are involved in the regulation of CSC. CSC exist in a wide array of tumor types, including leukemias, and brain, breast, prostate and colon tumors. Consequently, one of the key goals in cancer research over the past decade has been to develop therapeutic strategies to safely eliminate the CSC population without damaging the endogenous SSC population. A major hurdle to this goal lies in the identification of the key mechanisms that distinguish CSC from the normal endogenous tissue stem cells. This review will discuss the discovery of the specific CBP/catenin antagonist ICG-001 and the ongoing clinical development of the second generation CBP/catenin antagonist PRI-724. Importantly, specific CBP/catenin antagonists appear to have the ability to safely eliminate CSC by taking advantage of an intrinsic differential preference in the way SSC and CSC divide.

Isolating the role of elevated Phlda2 in asymmetric late fetal growth restriction in mice

Pleckstrin homology-like domain family A member 2 (PHLDA2) is a maternally expressed imprinted gene whose elevated expression has been linked to fetal growth restriction in a number of human studies. In mice, Phlda2 negatively regulates placental growth and limits the accumulation of placental glycogen. We previously reported that a three-copy transgene spanning the Phlda2 locus drove a fetal growth restriction phenotype late in gestation, suggesting a causative role for PHLDA2 in human growth restriction. However, in this mouse model, Phlda2 was overexpressed by fourfold, alongside overexpression of a second imprinted gene, Slc22a18. Here, we genetically isolate the role of Phlda2 in driving late fetal growth restriction in mice. We furthermore show that this Phlda2-driven growth restriction is asymmetrical, with a relative sparing of the brain, followed by rapid catch-up growth after birth, classic features of placental insufficiency. Strikingly, fetal growth restriction showed strain-specific differences, being apparent on the 129S2/SvHsd (129) genetic background and absent on the C57BL6 (BL6) background. A key difference between these two strains is the placenta. Specifically, BL6 placentae possess a more extensive endocrine compartment and substantially greater stores of placental glycogen. Taken together, these data support a direct role for elevated Phlda2 in limiting fetal growth but also suggest that growth restriction only manifests when there is limited placental reserve. These findings should be taken into account in interpreting the results from human studies.

TMEDA-derived biscationic amphiphiles: An economical preparation of potent antibacterial agents

Bis-alkylated derivatives of N,N,N',N'-tetramethylethylenediamine (TMEDA) represent a well-known class of versatile biscationic amphiphiles, owing to their low cost and ease of preparation. Asymmetric TMEDA derivatives, however, have been studied significantly less, particularly in regards to their antimicrobial properties. We have thus prepared a series of 36 mono- and bis-alkylated TMEDA derivatives to evaluate their inhibition of bacterial growth. This series of compounds showed low micromolar activity against a panel of four bacteria. Optimal inhibition was observed when the biscationic amphiphiles possessed modest asymmetry and were composed of between 20 and 24 total carbon atoms in the side chains. These amphiphiles were prepared in a simple two-step procedure, utilizing inexpensive materials and atom-economical reactions, making them practical for further development.

DNA asymmetry and cell fate regulation in stem cells

The semi-conservative nature of DNA replication has suggested that identical DNA molecules within chromatids are inherited by daughter cells after cell division. Numerous reports of non-random DNA segregation in prokaryotes and eukaryotes suggest that this is not always the case, and that epigenetic marks on chromatids, if not the individual DNA strands themselves, could have distinct signatures. Their selective distribution to daughter cells provides a novel mechanism for gene and cell fate regulation by segregating chromatids asymmetrically. Here we highlight some examples and potential mechanisms that can regulate this process. We propose that cellular asymmetry is inherently present during each cell division, and that it provides an opportunity during each cell cycle for moderating cell fates.

Strand-seq: a unifying tool for studies of chromosome segregation

Non random segregation of sister chromatids has been implicated to help specify daughter cell fate (the Silent Sister Hypothesis [1]) or to protect the genome of long-lived stem cells (the Immortal Strand Hypothesis [2]). The idea that sister chromatids are non-randomly segregated into specific daughter cells is only marginally supported by data in sporadic and often contradictory studies. As a result, the field has moved forward rather slowly. The advent of being able to directly label and differentiate sister chromatids in vivo using fluorescence in situ hybridization [3] was a significant advance for such studies. However, this approach is limited by the need for large tracks of unidirectional repeats on chromosomes and the reliance on quantitative imaging of fluorescent probes and rigorous statistical analysis to discern between the two competing hypotheses. A novel method called Strand-seq which uses next-generation sequencing to assay sister chromatid inheritance patterns independently for each chromosome [4] offers a comprehensive approach to test for non-random segregation. In addition Strand-seq enables studies on the deposition of chromatin marks in relation to DNA replication. This method is expected to help unify the field by testing previous claims of non-random segregation in an unbiased way in many model systems in vitro and in vivo.