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2.
Adv Mater ; 34(28): e2202552, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35560650

ABSTRACT

Despite being one of the most promising candidates for grid-level energy storage, practical aqueous zinc batteries are limited by dendrite formation, which leads to significantly compromised safety and cycling performance. In this study, by using single-crystal Zn-metal anodes, reversible electrodeposition of planar Zn with a high capacity of 8 mAh cm-2 can be achieved at an unprecedentedly high current density of 200 mA cm-2 . This dendrite-free electrode is well maintained even after prolonged cycling (>1200 cycles at 50 mA cm- 2 ). Such excellent electrochemical performance is due to single-crystal Zn suppressing the major sources of defect generation during electroplating and heavily favoring planar deposition morphologies. As so few defect sites form, including those that would normally be found along grain boundaries or to accommodate lattice mismatch, there is little opportunity for dendritic structures to nucleate, even under extreme plating rates. This scarcity of defects is in part due to perfect atomic-stitching between merging Zn islands, ensuring no defective shallow-angle grain boundaries are formed and thus removing a significant source of non-planar Zn nucleation. It is demonstrated that an ideal high-rate Zn anode should offer perfect lattice matching as this facilitates planar epitaxial Zn growth and minimizes the formation of any defective regions.

3.
J Genet Mutat Disord ; 1(1)2022 Jan.
Article in English | MEDLINE | ID: mdl-35465405

ABSTRACT

Juvenile idiopathic epilepsy (JIE) is a self-limiting neurological disorder with a suspected genetic predisposition affecting young Arabian foals of the Egyptian lineage. The condition is characterized by tonic-clonic seizures with intermittent post-ictal blindness, in which most incidents are sporadic and unrecognized. This study aimed to identify genetic components shared across a local cohort of Arabian foals diagnosed with JIE via a combined whole genome and targeted resequencing approach: Initial whole genome comparisons between a small cohort of nine diagnosed foals (cases) and 27 controls from other horse breeds identified variants uniquely shared amongst the case cohort. Further validation via targeted resequencing of these variants, that pertain to non-intergenic regions, on additional eleven case individuals revealed a single 19bp deletion coupled with a triple-C insertion (Δ19InsCCC) within the TRIM39-RPP21 gene readthrough that was uniquely shared across all case individuals, and absent from three additional Arabian controls. Furthermore, we have confirmed recent findings refuting potential linkage between JIE and other inherited diseases in the Arabian lineage, and refuted the potential linkage between JIE and genes predisposing a similar disorder in human newborns. This is the first study to report a genetic variant to be shared in a sub-population cohort of Arabian foals diagnosed with JIE. Further evaluation of the sensitivity and specificity of the Δ19InsCCC allele within additional cohorts of the Arabian horse is warranted in order to validate its credibility as a marker for JIE, and to ascertain whether it has been introduced into other horse breeds by Arabian ancestry.

5.
Hong Kong Med J ; 27(1): 18-26, 2021 02.
Article in English | MEDLINE | ID: mdl-33542158

ABSTRACT

PURPOSE: To document the epidemiology, presentation, clinical interventions, and outcomes of paediatric glaucoma in Hong Kong. METHODS: This multicentre territory-wide retrospective study was performed by reviewing charts of patients with paediatric glaucoma in six clusters of the Hong Kong Hospital Authority and The Chinese University of Hong Kong from 2006 to 2015. RESULTS: This study included 150 eyes of 98 patients with paediatric glaucoma (presenting age: 5.2±5.7 years). Of them, 35 eyes (23.3%) had primary congenital glaucoma, 22 eyes (14.7%) had juvenile open-angle glaucoma, and 93 eyes (62.0%) had secondary glaucoma. The most prevalent types of secondary glaucoma were lens-related after cataract extraction (18.0%), Axenfeld-Rieger anomaly (5.3%), uveitis (5.3%), Sturge-Weber syndrome (4.7%), and traumatic (3.3%). The most common clinical presentations were parental concerns (20.7%) including cloudy cornea (12.7%) and tearing/photophobia (8.0%), followed by poor visual acuity (18.0%), high intraocular pressure (13.3%), and strabismus (6.0%). The follow-up duration was 8.46±6.51 years. Furthermore, 63.2% of eyes with primary glaucoma and 45.2% of eyes with secondary glaucoma were treated surgically. The final visual acuity was 0.90±0.98 LogMAR; intraocular pressure was 18.4±6.6 mm Hg; and number of glaucoma medications was 2.22±1.61. CONCLUSION: Primary congenital glaucoma was most prevalent, followed by juvenile open-angle glaucoma and aphakic glaucoma. Most eyes with primary glaucoma required surgical treatment. Parental concerns were important clinical presentations. Basic assessments by healthcare providers to identify glaucoma signs (eg, poor visual acuity, high intraocular pressure, and strabismus) warranted prompt referral to an ophthalmologist.


Subject(s)
Child Health/statistics & numerical data , Glaucoma/epidemiology , Child , Child, Preschool , Cluster Analysis , Female , Glaucoma/etiology , Glaucoma/therapy , Hong Kong/epidemiology , Humans , Intraocular Pressure , Male , Ophthalmologic Surgical Procedures/statistics & numerical data , Prevalence , Strabismus/etiology , Visual Acuity
6.
J Am Chem Soc ; 143(8): 3205-3218, 2021 Mar 03.
Article in English | MEDLINE | ID: mdl-33596070

ABSTRACT

Understanding structural responses of metal-organic frameworks (MOFs) to external stimuli such as the inclusion of guest molecules and temperature/pressure has gained increasing attention in many applications, for example, manipulation and manifesto smart materials for gas storage, energy storage, controlled drug delivery, tunable mechanical properties, and molecular sensing, to name but a few. Herein, neutron and synchrotron diffractions along with Rietveld refinement and density functional theory calculations have been used to elucidate the responsive adsorption behaviors of defect-rich Zr-based MOFs upon the progressive incorporation of ammonia (NH3) and variable temperature. UiO-67 and UiO-bpydc containing biphenyl dicarboxylate and bipyridine dicarboxylate linkers, respectively, were selected, and the results establish the paramount influence of the functional linkers on their NH3 affinity, which leads to stimulus-tailoring properties such as gate-controlled porosity by dynamic linker flipping, disorder, and structural rigidity. Despite their structural similarities, we show for the first time the dramatic alteration of NH3 adsorption profiles when the phenyl groups are replaced by the bipyridine in the organic linker. These molecular controls stem from controlling the degree of H-bonding networks/distortions between the bipyridine scaffold and the adsorbed NH3 without significant change in pore volume and unit cell parameters. Temperature-dependent neutron diffraction also reveals the NH3-induced rotational motions of the organic linkers. We also demonstrate that the degree of structural flexibility of the functional linkers can critically be affected by the type and quantity of the small guest molecules. This strikes a delicate control in material properties at the molecular level.

7.
Food Chem Toxicol ; 149 Suppl 1: 111981, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33577945

ABSTRACT

The existing information supports the use of these materials as described in this safety assessment. The 167 materials identified in this assessment were evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Target data, read-across analogs and TTC show that these materials are not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the TTC for their respective Cramer Classes (see Fig. 1 below) and the exposure to these materials is below the TTC. The skin sensitization endpoint was completed using the DST for non-reactive and reactive materials (900 µg/cm2 and 64 µg/cm2, respectively); exposures are below the DST. The phototoxicity/photoallergenicity endpoints were evaluated based on UV spectra; these materials are not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; the materials were found not to be PBT as per the IFRA Environmental Standards, and their risk quotients, based on their current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Subject(s)
Odorants , Animals , Dose-Response Relationship, Drug , Humans , Quantitative Structure-Activity Relationship , Reproduction/drug effects , Risk Assessment , Toxicity Tests
8.
Food Chem Toxicol ; 149 Suppl 1: 111989, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33465460

ABSTRACT

The existing information supports the use of this material as described in this safety assessment. 3,7-Dimethyl-1,3,6-octatriene was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from 3,7-dimethyl-1,3,6-octatriene and read-across analog myrcene (ß-myrcene; CAS # 123-35-3) show that 3,7-dimethyl-1,3,6-octatriene is not expected to be genotoxic and provide a calculated margin of exposure (MOE) >100 for the repeated dose toxicity and developmental and reproductive toxicity endpoints. The skin sensitization endpoint was completed using the dermal sensitization threshold (DST) for non-reactive materials (900 µg/cm 2 ); exposure is below the DST. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; 3,7-dimethyl-1,3,6- octatriene is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the threshold of toxicological concern (TTC) for a Cramer Class I material, and the exposure to 3,7-dimethyl-1,3,6-octatriene is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; 3,7-dimethyl-1,3,6- octatriene was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental oncentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Subject(s)
Odorants , Animals , Dose-Response Relationship, Drug , Humans , Quantitative Structure-Activity Relationship , Reproduction/drug effects , Risk Assessment , Toxicity Tests
11.
Food Chem Toxicol ; 149 Suppl 1: 111982, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33454360

ABSTRACT

The existing information supports the use of this material as described in this safety assessment. p-Tolualdehyde was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity, skin sensitization potential, and environmental safety. Data from read-across analog benzaldehyde (CAS # 100-52-7) show that p-tolualdehyde is not expected to be genotoxic. Data from read-across analog cuminaldehyde (CAS # 122-03-2) provided p-tolualdehyde a No Expected Sensitization Induction Level (NESIL) of 1100 µg/cm2 for the skin sensitization endpoint. The repeated dose toxicity, developmental and reproductive toxicity, and local respiratory toxicity endpoints were completed using the threshold of toxicological concern (TTC) for a Cramer Class I material, and the exposure to p-tolualdehyde is below the TTC (0.03 mg/kg/day, 0.03 mg/kg/day, and 1.4 mg/day, respectively). The phototoxicity/photoallergenicity endpoints were evaluated based on data from read-across analog 4-ethylbenzaldehyde (CAS # 4748-78-1); p-tolualdehyde is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; p-tolualdehyde was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Subject(s)
Benzaldehydes/toxicity , Odorants , Animals , Benzaldehydes/chemistry , Dose-Response Relationship, Drug , Humans , Quantitative Structure-Activity Relationship , Reproduction/drug effects , Risk Assessment , Toxicity Tests
18.
Food Chem Toxicol ; 146 Suppl 1: 111730, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32898595

ABSTRACT

The existing information supports the use of this material as described in this safety assessment. 2-Methylpropyl pentanoate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog ethyl 2-methylbutyrate (CAS # 7452-79-1) show that 2-methylpropyl pentanoate is not expected to be genotoxic and provide a calculated margin of exposure (MOE) > 100 for the repeated dose toxicity and reproductive toxicity endpoints. Data from read-across analog isoamyl acetate (CAS # 123-92-2) show that there are no safety concerns for 2-methylpropyl pentanoate for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; 2-methylpropyl pentanoate is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the threshold of toxicological concern (TTC) for a Cramer Class I material; exposure is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; 2-methylpropyl pentanoate was found not to be persistent, bioaccumulative, and toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Subject(s)
Odorants/analysis , Perfume/toxicity , Valerates/toxicity , Animals , Databases, Chemical , Endpoint Determination , Humans , Mutagenicity Tests , Perfume/chemistry , Plants/drug effects , Registries , Reproduction/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests , Valerates/chemistry
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