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Irreversible blindness from glaucoma and optic neuropathies is attributed to retinal ganglion cells (RGCs) losing the ability to regenerate axons. While several transcription factors and proteins have demonstrated enhancement of axon regeneration after optic nerve injury, mechanisms contributing to the age-related decline in axon regenerative capacity remain elusive. In this study, we show that microRNAs are differentially expressed during RGC development and identify microRNA-19a (miR-19a) as a heterochronic marker; developmental decline of miR-19a relieves suppression of phosphatase and tensin homolog (PTEN), a key regulator of axon regeneration, and serves as a temporal indicator of decreasing axon regenerative capacity. Intravitreal injection of miR-19a promotes axon regeneration after optic nerve crush in adult mice, and it increases axon extension in RGCs isolated from aged human donors. This study uncovers a previously unrecognized involvement of the miR-19a-PTEN axis in RGC axon regeneration, and it demonstrates therapeutic potential of microRNA-mediated restoration of axon regenerative capacity in optic neuropathies., Graphical Abstract, This study demonstrates a previously unrecognized involvement of the miR-19a-PTEN axis in axon regenerative capacity of retinal ganglion cells (RGCs) during development. Mak and colleagues show that miR-19a promotes axon regeneration after optic nerve crush in adult mice, and it increases axon extension in RGCs isolated from aged human donors.

Background Self-collected specimens have been advocated to avoid infectious exposure to healthcare workers. Self-induced sputum in those with a productive cough and saliva in those without a productive cough have been proposed, but sensitivity remains uncertain. Methods We performed a prospective study in 2 regional hospitals in Hong Kong. Results We prospectively examined 563 serial samples collected during the virus shedding periods of 50 patients: 150 deep throat saliva (DTS), 309 pooled-nasopharyngeal (NP) and throat swabs, and 104 sputum. Deep throat saliva had the lowest overall reverse-transcriptase polymerase chain reaction (RT-PCR)-positive rate (68.7% vs 89.4% [sputum] and 80.9% [pooled NP and throat swabs]) and the lowest viral ribonucleic acid (RNA) concentration (mean log copy/mL 3.54 vs 5.03 [sputum] and 4.63 [pooled NP and throat swabs]). Analyses with respect to time from symptom onset and severity also revealed similar results. Virus yields of DTS correlated with that of sputum (Pearson correlation index 0.76; 95% confidence interval, 0.62–0.86). We estimated that the overall false-negative rate of DTS could be as high as 31.3% and increased 2.7 times among patients without sputum. Conclusions Deep throat saliva produced the lowest viral RNA concentration and RT-PCR-positive rate compared with conventional respiratory specimens in all phases of illness. Self-collected sputum should be the choice for patients with sputum.

Background & Aims Recreational ketamine use has emerged as an important health and social issue worldwide. Although ketamine is associated with biliary tract damage, the clinical and radiological profiles of ketamine-related cholangiopathy have not been well described. Methods Chinese individuals who had used ketamine recreationally at least twice per month for six months in the previous two years via a territory-wide community network of charitable organizations tackling substance abuse were recruited. Magnetic resonance cholangiography (MRC) was performed, and the findings were interpreted independently by two radiologists, with the findings analysed in association with clinical characteristics. Results Among the 343 ketamine users referred, 257 (74.9%) were recruited. The mean age and ketamine exposure duration were 28.7 (±5.8) and 10.5 (±3.7) years, respectively. A total of 159 (61.9%) had biliary tract anomalies on MRC, categorized as diffuse extrahepatic dilatation (n = 73), fusiform extrahepatic dilatation (n = 64), and intrahepatic ductal changes (n = 22) with no extrahepatic involvement. Serum alkaline phosphatase (ALP) level (odds ratio [OR] 1.007; 95% CI 1.002–1.102), lack of concomitant recreational drug use (OR 1.99; 95% CI 1.11–3.58), and prior emergency attendance for urinary symptoms (OR 1.95; 95% CI 1.03–3.70) had high predictive values for biliary anomalies on MRC. Among sole ketamine users, ALP level had an AUC of 0.800 in predicting biliary anomalies, with an optimal level of ≥113 U/L having a positive predictive value of 85.4%. Cholangiographic anomalies were reversible after ketamine abstinence, whereas decompensated cirrhosis and death were possible after prolonged exposure. Conclusions We have identified distinctive MRC patterns in a large cohort of ketamine users. ALP level and lack of concomitant drug use predicted biliary anomalies, which were reversible after abstinence. The study findings may aid public health efforts in combating the growing epidemic of ketamine abuse. Lay summary Recreational inhalation of ketamine is currently an important substance abuse issue worldwide, and can result in anomalies of the biliary system as demonstrated by magnetic resonance imaging. Although prolonged exposure may lead to further clinical deterioration, such biliary system anomalies might be reversible after ketamine abstinence. Clinical trial number: NCT02165488.

The investigation of a new energy source was strongly demanded during the oil crisis in the 1970s. The utilization of microalgae in biofuel production has caught much attention due to the high constituent of lipids content which can be used as feedstock to achieve high biofuel production rate. Algae drying is a complicated transient operation of simultaneous heat and mass transfer with various rate processes. Liquid from wet material is evaporated with the heat supply during the drying process. Algae surface charge, size, and cell density are associated with the stability of microalgae in growth medium, which influences their separability from aqueous suspensions. The electric interactions between algae cells and cell interactions with the surrounding culture broth could contribute to the stability of the algae suspension. Destabilisation of colloidal suspension like in an algae culture is attainable by the presence of organic polymer by specific interactions at the ionic or atomic levels.

Background Congenital adrenal hyperplasia (CAH) caused by 21-hydroxylase deficiency (21OHD) is an autosomal recessive disorder due to mutation in the CYP21A2 gene. Objective To elucidate the genetic basis of 21-hydroxylase-deficient CAH in Hong Kong Chinese patients. Patients and methods Mutational analysis of the CYP21A2 gene was performed on 35 Hong Kong Chinese patients with 21OHD using direct DNA sequencing and multiplex ligation-dependent probe amplification (MLPA). Results The genetic findings of 21 male and 14 female patients are the following: c.293-13A/C>G (intron 2 splice site; 20 alleles), p.I172N (13), p.R356W (7), p.Q318X (4). A total of 20 mutant alleles contained gross deletion/conversion of all or part of the CYP21A2 gene. A novel mutation, c.1367delA (p.D456fs), was detected in one patient. One patient had only a heterozygous mutation detected. Out of 35 patients, 16 would have been incorrectly genotyped if either DNA sequencing or MLPA alone was used for molecular analysis. Conclusions The frequency of various mutations in the studied patients differs from those reported in other Asian populations. Gross deletion/conversion accounts for nearly one-third of the genetic defects. Therefore, laboratories must include methods for detecting point mutations as well as gross deletions/conversions to avoid misinterpretation of genotype. Genotyping has increasingly been proven to be a useful tool for supplementing, if not replacing, hormonal profiling for the diagnosis of 21OHD.

Clinical and preclinical studies suggest that the hippocampus has a role in the pathophysiology of major depression. In the learned helplessness (LH) animal model of depression after inescapable shocks (ISs) animals that display LH behavior have reduced cell proliferation in the hippocampus; this effect can be reversed by antidepressant treatment. Using this model, we compared rats that displayed LH behavior and rats that did not show LH behavior (NoLH) after ISs to determine whether reduced hippocampal cell proliferation is associated with the manifestation of LH behavior or is a general response to stress. Specifically, we examined cell proliferation, neurogenesis, and synaptic function in dorsal and ventral hippocampus of LH and NoLH animals and control rats that were not shocked. The LH rats had showed reduced cell proliferation, neurogenesis, and synaptic transmission in the dorsal hippocampus, whereas no changes were seen in the ventral hippocampus. These changes were not observed in the NoLH animals. In a group of NoLH rats that received the same amount of electrical shock as the LH rats to control for the unequal shocks received in these two groups, we observed changes in Ki-67(+) cells associated with acute stress. We conclude that reduced hippocampal cell proliferation and neurogenesis are associated with the manifestation of LH behavior and that the dorsal hippocampus is the most affected area.

Background Both gestational diabetes mellitus (GDM) and late-preterm delivery at 34–36 weeks' gestation are independently associated with neonatal respiratory complications, but it is unknown whether their combination increases further its risk. We therefore appraised the independent effect of GDM on the respiratory outcome of late-preterm infants. Methods In a retrospective cohort study, respiratory outcome of 911 infants delivered at 34–36 weeks' gestation between 1 January 2009 and 30 August 2012 from mothers with GDM (study group, n = 130) was compared with infants delivered at the same gestation by mothers without GDM (control group, n = 781). Results The study group had significantly higher incidence of transient tachypnoea of newborn (TTN, p = 0.02) and air leak (p = 0.012), and required more respiratory support, including oxygen, continuous positive airway pressure (CPAP), mechanical ventilation and neonatal intensive care, with a longer length of hospital stay, but not duration on respiratory support. On logistic regression analysis, GDM is an independent risk factor for TTN (aOR = 1.5, 95% C.I.1.0–2.4), CPAP (aOR = 2.37, 95% C.I. 1.05–4.89), mechanical ventilation (aOR = 4.02 95% C.I. 1.57–10.32) and neonatal intensive care (aOR 1.83, 95% C.I. 1.05–3.87). Conclusions Our results demonstrated an independent effect of GDM on the risk of severe respiratory complications in late-preterm infants. Additional close monitoring and timely intervention are necessary in the management of these infants.

A cationic aminoethylsulphonyl dye has been prepared by the reaction of ammonia with a vinylsulphonyl cationic dye. The result dyes nylon optimally from dyebaths set at pH > 10; addition of a substantive crosslinker, 2-chloro-4,6-di(aminobenzene-4′-sulphatoethylsulphone)-s-triazine [XLC], has been employed to covalently fix the dye to amine groups in the nylon fibre. Optimum exhaustion/fixation results have been achieved by dyeing at pH 10 for 1 h at the boil, adiusting the bath pH to 8, adding the crosslinker and continuing to boil for at least 1 h.

A mono-aminoalkyl-s-triazine polysulphonated dye was used as a model nucleophilic dye. When applied to nylon 6,6 this dye gave good uptake under midly acidic conditions but, as expected, no covalent bonding was observed. When such dyeings were after-treated with anionic dispersions of the specially synthesised, fibre substantive, cross-linking agent, 2-chloro-4,6-di(aminobenzene-4′-vinylsulphone)-s-triazine [XLC-VS], a very significant degree of covalent bonding was achieved.

Production of murine monoclonal antibodies to the low prevalence MNS antigen Henshaw (He; MNS6) has enabled more detailed study of this antigen. Using these directly hemagglutinating anti-He, red blood cells (RBCs) from 1695 people of African origin were screened in the USA and England. The prevalence of He+ samples among these donors was 2.1%. In Natal, blood samples from 1218 black donors were screened with rabbit anti-He. The prevalence of He+ donors in this population was 7.0%. Immunoblotting confirmed that the He antigen is carried on an erythrocyte membrane component with a molecular mass that is indistinguishable from glycophorin B. Hemagglutination and immunoblotting demonstrated that ten of 56 He+ samples tested more extensively had a reduced expression of the He antigen. The majority of He+ RBCs were S+; those He+ RBC samples that were S-s+ more frequently had a weakened expression of He.

The crosslinker 1,3,5-triacroylamino-hexahydro-s-triazine was synthesised and applied to nylon-6,6 fabric from a long liquor; its substantivity was found to be optimum at pH 8 but was rated as only moderate, approximately 30–40% of the agent being absorbed from boiling aqueous solutions when an initial amount of 3% omf was applied. Amino-alkyl dyes were prepared from reaction of existing chloro-triazinyl reactive dyes with ethylene diamine. The amino-alkyl group in these dyes behaved as an excellent nucleophile and could be crosslinked to the fibre amino groups using the above crosslinker to obtain covalently bound dyeings of excellent wet fastness.

A reactive crosslinker (XLC) containing two sulphatoethylsulphone and one chloro-s-triazine residue has been synthesised and applied to nylon. The pretreated nylon shows reduced substantivity and reactivity towards a model reactive dye, CI Reactive Red 3. If these pretreated fibres are reacted with ammonia, they then show enhanced dye uptake and fixation when dyed with this dye. Opposite effects are achieved if the above reactive dye is converted to a nucleophilic aminoalkyl-s-triazine dye by reaction with ethylene diamine; the nucleophilic dye exhibits a high degree of covalent bonding only on the XLC treated nylon.

The effects of vitamin E, Irganox 1010, and BHT as antioxidants for reducing the release of off-flavor (both off-odor and off-taste) from blow- molded HDPE bottles were investigated. A sensory study was conducted and showed that bottles containing vitamin E had a lower odor intensity and a higher acceptability for storage of drinking water compared to bottles contain ing Irganox 1010 or BHT. Forty-seven volatile compounds were identified to release from the bottles using the purge-and-trap GC/MS analysis. Those vola tile compounds, ranging from C 6 to C18, belonged to the groups of n-alkane, 1- alkene, aldehyde, ketone, phenolic, olefin, and paraffin; among them aldehydes and ketones were the most important due to their very low odor thresholds. The bottles containing vitamin E were found to release the least amount of alde hydes and ketones compared to bottles containing Irganox 1010 or BHT. The acceptability of drinking water is correlated inversely to the intensity of odor and taste as well as to the aldehyde/ketone concentration. Therefore vitamin E, although used at about 20% the concentration of Irganox 1010 or BHT, is a superior antioxidant for reducing off-odor and off-taste from HDPE bottles.

Polymeric meshes in the form of knitted nets are commonly used in the surgical repair of pelvic organ prolapses. Although a number of these prosthetic meshes are commercially available, there is little published data on their mechanical performance, in particular on the change in stiffness under the repeated loading experienced in vivo. In this in vitro study, cyclic tensile loading was applied to rectangular strips of four different commercially available meshes. The applied force and resultant displacement was monitored throughout the tests in order to evaluate the change in stiffness. In addition, each mesh was randomly marked using indelible ink in order to permit the use of threedimensional digital image correlation to evaluate local displacements during the tests. However, the scale and form of the deformation experienced by some of the meshes made correlation difficult so that confirmation of the values of stiffness were only obtained for two meshes. The results demonstrate that all the meshes experience an increase in stiffness during cyclic loading, that in most cases cyclic creep occurs and in some cases large-scale, irreversible reorganisation of the mesh structure occurs after as few as 200 cycles at loads of the order of 10N.

Cylindrical model food samples containing 3% agar gel were shielded with metal bands during microwave heating. the metal bands were arranged in various patterns, with different spacing and orientation. the focus of this work was to study-how these patterns could affect the heating uniformity and power absorption in the samples. the heating rates of the samples during microwaving were measured with fiberoptic temperature sensors. A two-factor central composite rotatable design and the corresponding response surface methodology were used to analyze the data. It was found that orientation was an important design parameter, and it was possible to design patterns that could greatly increase the heating uniformity without greatly reducing the power absorption.

Reports the progress on the NSF grant EID-92-12122 entitled "Analysis, control, and optimization of discrete event dynamic systems". The paper covers the following topics: NSF research curriculum initiative; DEDS definition; curriculum development effort; and instructional simulation lab examples.

For a Markovian discrete-event dynamic system (DEDS), an approach has been proposed for generating an event time sequence independently from the state updating process. In simulation environments, this allows one to efficiently construct state sequences of the system under various parameter values, using only a common nominal event time sequence. The authors show how to use this approach in a real-time setting by directly observing a trajectory of a DEDS. They apply this approach to the crash time prediction problem, where they are interested in estimating the time when an M/M/1 system first reaches a given queue length as a function of different arrival rates. >

A new X-Y-axes control system is developed for spring formation machines. Based on a newly developed algorithm in a pseudo-code version, a hardware architecture for such systems is derived by using the codesign methodology. Owing to this new approach to motor driven mechanisms, production rate and accuracy of SFMs are greatly improved and the design criteria are duly met.

A variable pulse frequency generation algorithm is proposed for driving AC motors with higher precision control and faster production rate. The derivation of this algorithm is presented along with a mathematical proof. Owing to its simplicity, the algorithm can be hardware implemented with only two 2K (Actel) FPGA gates.

Two versions of an unsupervised learning algorithm for pattern recognition are compared by means of numerical calculations based on two-dimensional ellipsoidal pattern distributions.

A theoretical pattern recognition model is constructed to explain a experimental self-corrective character recognition scheme which was recently described.