Pollen grains are microscopic so their identification and quantification has, for decades, depended upon human observers using light microscopes: a labour‐intensive approach. Modern improvements in ...computing and imaging hardware and software now bring automation of pollen analyses within reach. In this paper, we provide the first review in over 15 yr of progress towards automation of the part of palynology concerned with counting and classifying pollen, bringing together literature published from a wide spectrum of sources. We consider which attempts offer the most potential for an automated palynology system for universal application across all fields of research concerned with pollen classification and counting. We discuss what is required to make the datasets of these automated systems as acceptable as those produced by human palynologists, and present suggestions for how automation will generate novel approaches to counting and classifying pollen that have hitherto been unthinkable.
Although deep learning has revolutionized protein structure prediction, almost all experimentally characterized de novo protein designs have been generated using physically based approaches such as ...Rosetta. Here, we describe a deep learning-based protein sequence design method, ProteinMPNN, that has outstanding performance in both in silico and experimental tests. On native protein backbones, ProteinMPNN has a sequence recovery of 52.4% compared with 32.9% for Rosetta. The amino acid sequence at different positions can be coupled between single or multiple chains, enabling application to a wide range of current protein design challenges. We demonstrate the broad utility and high accuracy of ProteinMPNN using x-ray crystallography, cryo-electron microscopy, and functional studies by rescuing previously failed designs, which were made using Rosetta or AlphaFold, of protein monomers, cyclic homo-oligomers, tetrahedral nanoparticles, and target-binding proteins.
A 3D hybrid zinc formate framework, NH4Zn(HCOO)3, possessing an acs topology, shows a high degree of mechanical anisotropy and negative linear compressibility (NLC) along its c axis. High-pressure ...single-crystal X-ray diffraction studies and density functional theory calculations indicate that contraction of the Zn–O bonds and tilting of the formate ligands with increasing pressure induce changes in structure that result in shrinkage of the a and b axes and the NLC effect along c.
Persistence of Influenza on Surfaces Thompson, Katy-Anne; Bennett, Allan
The Journal of hospital infection,
02/2017, Letnik:
95, Številka:
2
Journal Article
Recenzirano
Summary Background Close contact transmission (either direct or large droplet/droplet nuclei) is considered the main driver of influenza outbreaks but there is limited information regarding the role ...of fomites in transmission. Aim To investigate the surface stability of influenza strains to investigate the role of fomites in transmission. Methods In this study both the viability and qt-RT-PCR signal of five influenza strains (A/PR/08/34/H1N1, A/Cal/07/09/H1N1, A/Cal/04/09/H1N1, A/Sol/54/6/H1N1, and A/Bris/59/7/H1N1) seeded onto 3 surfaces (cotton, microfibre and stainless steel) was assessed over time. Coupons of material were seeded with 10μl of a 106 -108 pfu/ml suspension of cell culture derived virus stock supplemented with 0.3% bovine serum albumin. Coupons were assayed by plaque assay and qt-RT-PCR at 1, 24 hours and weekly for 7 weeks using a vortex mixing elution method. Findings Viable virus was detected from coupons for up to 2 (stainless steel) and 1 (cotton and microfibre) weeks, whereas detection of viruses by PCR could be made for the entire 7 week study period. No strain differences were found. Ninety-nine % reduction values (as a function of the seeding stock) were determined to be 17.7 hours for cotton (R2 = 0.86), 34.3 hours for microfibre (R2 = 0.80) and 174.9 hours for stainless steel (R2 = 0.98). Conclusion Viable influenza was recovered from surfaces for up to 2 weeks. In contrast influenza could be detected by PCR for >7 weeks. These results have important implications for determining infection control protocols, cleaning regimes and sampling methods in health-care settings.
The porosity of a glass formed by melt-quenching a metal-organic framework, has been characterized by positron annihilation lifetime spectroscopy. The results reveal porosity intermediate between the ...related open and dense crystalline frameworks ZIF-4 and ZIF-zni. A structural model for the glass was constructed using an amorphous polymerization algorithm, providing additional insight into the gas-inaccessible nature of porosity and the possible applications of hybrid glasses.
When transistor gate insulators have nanometer-scale equivalent oxide thickness (EOT), the gate capacitance (
) becomes smaller than the oxide capacitance (
) due to the quantum capacitance and ...charge centroid capacitance of the channel. Here, we study the capacitance of monolayer MoS
as a prototypical two-dimensional (2D) channel while considering spatial variations in the potential, charge density, and density of states. At 0.5 nm EOT, the monolayer MoS
capacitance is smaller than its quantum capacitance, limiting the single-gated
of an
-type channel to between 63% and 78% of
, for gate overdrive voltages between 0.5 and 1 V. Despite these limitations, for dual-gated devices, the on-state
of monolayer MoS
is 50% greater than that of silicon at 0.5 nm EOT and more than three times that of InGaAs at 1 nm EOT, indicating that such 2D semiconductors are promising for improved gate control of nanoscale transistors at future technology nodes.
Abstract
Auxin is a key regulator of plant growth and development, but the causal relationship between hormone transport and root responses remains unresolved. Here we describe auxin uptake, together ...with early steps in signaling, in
Arabidopsis
root hairs. Using intracellular microelectrodes we show membrane depolarization, in response to IAA in a concentration- and pH-dependent manner. This depolarization is strongly impaired in
aux1
mutants, indicating that AUX1 is the major transporter for auxin uptake in root hairs. Local intracellular auxin application triggers Ca
2+
signals that propagate as long-distance waves between root cells and modulate their auxin responses. AUX1-mediated IAA transport, as well as IAA
-
triggered calcium signals, are blocked by treatment with the SCF
TIR1/AFB
- inhibitor auxinole. Further, they are strongly reduced in the
tir1afb2afb3
and the
cngc14
mutant. Our study reveals that the AUX1 transporter, the SCF
TIR1/AFB
receptor and the CNGC14 Ca
2+
channel, mediate fast auxin signaling in roots.
When transistor gate insulators have nanometer-scale equivalent oxide thickness (EOT), the gate capacitance (C G) becomes smaller than the oxide capacitance (C ox) due to the quantum capacitance and ...charge centroid capacitance of the channel. Here, we study the capacitance of monolayer MoS2 as a prototypical two-dimensional (2D) channel while considering spatial variations in the potential, charge density, and density of states. At 0.5 nm EOT, the monolayer MoS2 capacitance is smaller than its quantum capacitance, limiting the single-gated C G of an n-type channel to between 63% and 78% of C ox, for gate overdrive voltages between 0.5 and 1 V. Despite these limitations, for dual-gated devices, the on-state C G of monolayer MoS2 is 50% greater than that of silicon at 0.5 nm EOT and more than three times that of InGaAs at 1 nm EOT, indicating that such 2D semiconductors are promising for improved gate control of nanoscale transistors at future technology nodes.
Here, absolute cross sections for the addition of s- and d-wave neutrons to 14C and 14N have been determined simultaneously via the (d,p) reaction at 10 MeV/u. The difference between the neutron and ...proton separation energies, ΔS, is around -20 MeV for the 14C+n system and +8 MeV for 14N+n. The population of the 1s1/2 and 0d5/2 orbitals for both systems is reduced by a factor of approximately 0.5 compared with the independent single-particle model, or about 0.6 when compared with the shell model. This finding strongly contrasts with results deduced from intermediate-energy knockout reactions between similar nuclei on targets of 9Be and 12C. The simultaneous technique used removes many systematic uncertainties.
Introduction
While monophasic and relapsing forms of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are increasingly diagnosed world-wide, consensus on management is yet to ...be developed.
Objective
To survey the current global clinical practice of clinicians treating MOGAD.
Method
Neurologists worldwide with expertise in treating MOGAD participated in an online survey (February–April 2019).
Results
Fifty-two responses were received (response rate 60.5%) from 86 invited experts, comprising adult (78.8%, 41/52) and paediatric (21.2%, 11/52) neurologists in 22 countries. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ≥ 3 months; though less commonly when treating children. After an index event, 60% (31/51) usually start steroid-sparing maintenance therapy (MT); after ≥ 2 attacks 92.3% (48/52) would start MT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on MT initiation. Commonly used first line MTs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line MT (54.5%; 6/11). Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop MT.
Conclusion
Current treatment of MOGAD is highly variable, indicating a need for consensus-based treatment guidelines, while awaiting definitive clinical trials.
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