An analog-AI chip for energy-efficient speech recognition and transcription.

Models of artificial intelligence (AI) that have billions of parameters can achieve high accuracy across a range of tasks1,2, but they exacerbate the poor energy efficiency of conventional general-purpose processors, such as graphics processing units or central processing units. Analog in-memory computing (analog-AI)3-7 can provide better energy efficiency by performing matrix-vector multiplications in parallel on 'memory tiles'. However, analog-AI has yet to demonstrate software-equivalent (SWeq) accuracy on models that require many such tiles and efficient communication of neural-network activations between the tiles. Here we present an analog-AI chip that combines 35 million phase-change memory devices across 34 tiles, massively parallel inter-tile communication and analog, low-power peripheral circuitry that can achieve up to 12.4 tera-operations per second per watt (TOPS/W) chip-sustained performance. We demonstrate fully end-to-end SWeq accuracy for a small keyword-spotting network and near-SWeq accuracy on the much larger MLPerf8 recurrent neural-network transducer (RNNT), with more than 45 million weights mapped onto more than 140 million phase-change memory devices across five chips.

Improving the optoelectronic properties of monolayer MoS2field effect transistor through dielectric engineering.

The reduced dielectric screening in atomically thin two-dimensional materials makes them very sensitive to the surrounding environment, which can be modulated to tune their optoelectronic properties. In this study, we significantly improved the optoelectronic properties of monolayer MoS2by varying the surrounding environment using different liquid dielectrics, each with a specific dielectric constant ranging from 1.89 to 18. Liquid mediums offer the possibility of environment tunability on the same device. For a back-gated field effect transistor, the field effect mobility exhibited more than two-order enhancement when exposed to a high dielectric constant medium. Further investigation into the effect of the dielectric environment on the optoelectronic properties demonstrated a variation in photoresponse relaxation time with the dielectric medium. The rise and decay times were observed to increase and decrease, respectively, with an increase in the dielectric constant of the medium. These results can be attributed to the dielectric screening provided by the surrounding medium, which strongly modifies the charged impurity scattering, the band gap, and defect levels of monolayer MoS2. These findings have important implications for the design of biological and chemical sensors, particularly those operating in a liquid environment. By leveraging the tunability of the dielectric medium, we can optimize the performance of such sensors and enhance their detection capabilities.

Intravenous thrombolysis for multi-ethnic Asians with acute ischaemia stroke in Malaysian public primary stroke centres versus acute stroke ready hospitals: Comparison of real-world clinical outcomes.

INTRODUCTION: Intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator is beneficial in acute ischaemic stroke (AIS). We aim to compare the realworld clinical outcomes and service efficiency of IVT in Malaysian primary stroke centres (PSCs) versus acute stroke ready hospitals (ASRHs). MATERIALS AND METHODS: We conducted a multi-centre cohort study involving 5 PSCs and 7 ASRHs in Malaysia. Through review of medical records of AIS patients who received IVT from 01 January 2014 to 30 June 2021, real-world data was extracted for analysis. Univariate and multivariate regression models were employed to evaluate the role of PSCs versus ASRHs in post-IVT outcomes and complications. Statistical significance was set at p<0.05. RESULTS: A total of 313 multi-ethnic Asians, namely 231 from PSCs and 82 from ASRHs, were included. Both groups were comparable in baseline demographic, clinical, and stroke characteristics. The efficiency of IVT delivery (door-toneedle time), functional outcomes (mRS at 3 months post- IVT), and rates of adverse events (intracranial haemorrhages and mortality) following IVT were comparable between the 2 groups. Notably, 46.8% and 48.8% of patients in PSCs and ASRHs group respectively (p=0.752) achieved favourable functional outcome (mRS≤1 at 3 months post-IVT). Regression analyses demonstrated that post-IVT functional outcomes and adverse events were independent of the role of PSCs or ASRHs. CONCLUSION: Our study provides real-world evidence which suggests that IVT can be equally safe, effective, and efficiently delivered in ASRHs. This may encourage the establishment of more ASRHs to extend the benefits of IVT to a greater proportion of stroke populations and enhance the regional stroke care.

Comparison of nested-multiplex, Taqman & SYBR Green real-time PCR in diagnosis of amoebic liver abscess in a tertiary health care institute in India.

BACKGROUND & OBJECTIVES: Amoebiasis is a common parasitic infection caused by Entamoeba histolytica and amoebic liver abscess (ALA) is the most common extraintestinal manifestation of amoebiasis. The aim of this study was to standardise real-time PCR assays (Taqman and SYBR Green) to detect E. histolytica from liver abscess pus and stool samples and compare its results with nested-multiplex PCR. METHODS: Liver abscess pus specimens were subjected to DNA extraction. The extracted DNA samples were subjected to amplification by nested-multiplex PCR, Taqman (18S rRNA) and SYBR Green real-time PCR (16S-like rRNA assays to detect E. histolytica/E. dispar/E. moshkovskii). The amplification products were further confirmed by DNA sequence analysis. Receiver operator characteristic (ROC) curve analysis was done for nested-multiplex and SYBR Green real-time PCR and the area under the curve was calculated for evaluating the accuracy of the tests to dignose ALA. RESULTS: In all, 17, 19 and 25 liver abscess samples were positive for E. histolytica by nested-multiplex PCR, SYBR Green and Taqman real-time PCR assays, respectively. Significant differences in detection of E. histolytica were noted in the real-time PCR assays evaluated ( P<0.0001). The nested-multiplex PCR, SYBR Green real-time PCR and Taqman real-time PCR evaluated showed a positivity rate of 34, 38 and 50 per cent, respectively. Based on ROC curve analysis (considering Taqman real-time PCR as the gold standard), it was observed that SYBR Green real-time PCR was better than conventional nested-multiplex PCR for the diagnosis of ALA. INTERPRETATION & CONCLUSIONS: Taqman real-time PCR targeting the 18S rRNA had the highest positivity rate evaluated in this study. Both nested multiplex and SYBR Green real-time PCR assays utilized were evaluated to give accurate results. Real-time PCR assays can be used as the gold standard in rapid and reliable diagnosis, and appropriate management of amoebiasis, replacing the conventional molecular methods.

Cytokine release assays: current practices and future directions.

As a result of the CD28 superagonist biotherapeutic monoclonal antibody (TGN 1412) "cytokine storm" incident, cytokine release assays (CRA) have become hazard identification and prospective risk assessment tools for screening novel biotherapeutics directed against targets having a potential risk for eliciting adverse pro-inflammatory clinical infusion reactions. Different laboratories may have different strategies, assay formats, and approaches to the reporting, interpretation, and use of data for either decision making or risk assessment. Additionally, many independent contract research organizations (CROs), academic and government laboratories are involved in some aspect of CRA work. As a result, while some pharmaceutical companies are providing CRA data as part of the regulatory submissions when necessary, technical and regulatory practices are still evolving to provide data predictive of cytokine release in humans and that are relevant to safety. This manuscript provides an overview of different approaches employed by the pharmaceutical industry and CROs, for the use and application of CRA based upon a survey and post survey follow up conducted by ILSI-Health and Environmental Sciences Institute (HESI) Immunotoxicology Committee CRA Working Group. Also discussed is ongoing research in the academic sector, the regulatory environment, current limitations of the assays, and future directions and recommendations for cytokine release assays.

Use of just-about-right scales and penalty analysis to determine appropriate concentrations of stevia sweeteners for vanilla yogurt.

With the mainstream emergence of natural sweeteners such as stevia, which is available in different commercial formulations, suitability for yogurt needs to be validated. The present study aimed to determine the appropriate concentration level of 3 processed stevia sweeteners/supplements in commercial plain low-fat yogurt flavored with natural vanilla. Three different levels of sucrose, aspartame, an erythritol and 95% rebaudiana A stevia sweetener, a 95% pure mix of maltodextrin and steviol glycosides, and a cold water stevia extract were used in the study. The just-about-right level for each sweetener and consumer acceptability of each naturally flavored low-fat vanilla yogurt were evaluated. Results from penalty analysis demonstrated that only 0.7% of stevia containing maltodextrin and 95% steviol glycoside was necessary, whereas higher levels (between 4.0 to 5.5%) were more appropriate for stevia containing erythritol and 95% rebaudiana A or cold water extract of stevia, respectively. The concentrations of stevia sweeteners used influenced the perceived sweetness and sourness. In general, consumers disliked the yogurt sweetened with stevia or aspartame, and neither disliked nor liked the yogurt sweetened with sucrose, which was largely driven by perceived sourness of the base yogurt. The findings underline the importance of careful selection of stevia type and concentration as well as optimizing yogurt cultures and fermentation conditions before product launch.

2-(4,5-Dimeth-oxy-2-nitro-phen-yl)-4-meth-oxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde.

In the title compound, C28H22N2O8S, the carbazole ring system is roughly planar, with a maximum deviation of 0.084 (3) Šfor the C atom connected to the 4,5-dimeth-oxy-2-nitro-phenyl ring. The dihedral angle between the carbazole system and the dimeth-oxy-substituted nitro-phenyl ring is 57.05 (10)°. The aldehyde C atom deviates by 0.164 (5) Šfrom its attached carbazole ring system. The mol-ecular structure is stabilized by C-H⋯O inter-actions which generate two S(6) and one S(7) ring motif. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming R 3 (3)(15) ring motifs, which are further crosslinked by R 3 (2)(19) ring motifs, resulting in (002) layers. The crystal packing also features C-H⋯π inter-actions.

2-(4,5-Di-chloro-2-nitro-phen-yl)-4-meth-oxy-3-methyl-9-phenyl-sulfon-yl-9H-carbazole.

In the title compound, C26H18Cl2N2O5S, the carbazole ring system is essentially planar with a maximum deviation of 0.0498 (16) Šfor the N atom. The carbazole ring system is almost orthogonal to the phenyl-sulfonyl and di-chloro-substituted nitro-phenyl rings, making dihedral angles of 84.23 (7) and 85.46 (12)°, respectively. The mol-ecular structure features intra-molecular C-H⋯O inter-actions, which generate two S(6) ring motifs. In the crystal, mol-ecules are linked by C-Cl⋯O halogen bonds [3.016 (3) Å, 166.63 (5)°], which generate infinite C(8) chains running parallel to [010].

2-(4-Chloro-2-nitro-phen-yl)-4-meth-oxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde.

In the sterically hindered title compound, C26H17ClN2O6S, the carbazole ring has a maximum deviation from planarity of 0.067 (4) Šfor the C atom connected to the aldehyde group. The carbazole moiety forms a dihedral angle of 72.8 (1)° with the nitro-substituted benzene ring. The O atom of the meth-oxy group deviates by 0.186 (1) Šfrom the adjacent carbazole moiety. The phenyl-sulfonyl group forms intra-molecular C-H⋯O bonds between sulfone O atoms and the carbazole moiety, resulting in two S(6) rings. In the crystal, the nitrated benzene rings are linked via C-H⋯O inter-actions forming infinite C(7) chains along [100]. The crystal packing is also characterized by C-H⋯π inter-actions, which result in inversion dimers.

2-(4,5-Dimeth-oxy-2-nitro-phen-yl)-4-meth-oxy-3-methyl-9-phenyl-sulfonyl-9H-carbazole.

In the title compound, C28H24N2O7S, the carbazole system is essentially planar, with a maximum deviation of 0.0644 (19) Šfor the C atom connected to the 4,5-dimeth-oxy-2-nitro-phenyl group. The dihedral angle between the carbazole moiety and the dimethoxy-substituted nitrophenyl ring is 58.55 (7)°. The sulfonyl group forms two intra-molecular C-H⋯O bonds with the adjacent carbazole system, forming two cyclic S(6) motifs. In the crystal, mol-ecules are linked along the a axis in bands consisting of cyclic R 3 (3)(15) motifs through two further C-H⋯O hydrogen bonds.

Crystal structure of 2,9-diphenyl-17λ(6)-thia-tetra-cyclo-[8.7.0.0(3,8).0(11,16)]hepta-deca-1(10),2,4,6,8,11(16),12,14-octa-ene-17,17-dione.

The title compound, C28H18O2S, is composed of a naphthalene ring system fused with a benzo-thio-phene ring and attached to two phenyl rings. The phenyl rings make dihedral angles of 70.92 (8) and 79.23 (8)° with the essentially planar naphthalene ring system (r.m.s. deviation = 0.031 Å). There is an intra-molecular C-H⋯π inter-action present. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds which generate C(7) zigzag chains running parallel to [10-1]. The chains are linked via further C-H⋯π inter-actions, forming a three-dimensional structure.

3,10,14,21-Tetra-kis(4-meth-oxy-phen-yl)penta-cyclo-[11.8.0.0(2,11).0(4,9).0(15,20)]henicosa-1(21),2,4(9),5,7,10,13,15(20),16,18-decaen-12-one chloro-form monosolvate.

The asymmetric unit of the title compound, C49H36O6·CHCl3, contains half an organic mol-ecule, the complete mol-ecule being generated by the operation of a crystallographic twofold rotation axis, and half a highly disordered chloro-form mol-ecule. The contribution to the diffraction pattern of the latter was removed using the program SQUEEZE in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]; the unit-cell characteristics take into account the presence of CHCl3. The dihedral angles between the planes of the naphthalene ring system and the meth-oxy-benzene rings are 71.05 (7) (syn to the central C=O group) and 57.27 (6)° (anti to the central C=O group). In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating C(12) chains running parallel to the b axis.

Methyl 3'-benzyl-4'-(2,4-di-chloro-phen-yl)-1'-methyl-2-oxo-spiro-[indoline-3,2'-pyrrolidine]-3'-carboxyl-ate.

In the title compound, C27H24Cl2N2O3, the indole ring system is essentially planar, with a maximum deviation of 0.082 (2) Šfor the carbonyl C atom. It makes a dihedral angle of 88.53 (6)° with the mean plane of the 4-methyl-pyrrolidine ring, which adopts an envelope conformation with the N atom at the flap position. The mol-ecular structure is stabilized by intra-molecular C-H⋯O hydrogen bonds, which generate S(6) and S(7) ring motifs, and an intra-molecular π-π inter-action involving the benzyl and di-chloro-substituted benzene rings [centroid-centroid distance = 3.6291 (11) Å]. In the crystal, mol-ecules are linked via N-H⋯O hydrogen bonds, forming C(7) chains running parallel to [10-1].

Methyl 3'-(2,5-di-methyl-benz-yl)-1'-methyl-2-oxo-4'-phenyl-spiro-[indoline-3,2'-pyrrolidine]-3'-carboxyl-ate chloro-form monosolvate.

In the title solvate, C29H30N2O3·CHCl3, the dihedral angle between the indole ring system (r.m.s. deviation = 0.050 Å) and the 4-methyl-pyrrolidine ring is 88.88 (8)°. The latter ring adopts an envelope conformation with the N atom as the flap. Its mean plane makes dihedral angles of 86.94 (11) and 42.08 (9)° with the phenyl and di-methyl-benzene rings, respectively. The mol-ecular conformation is stabilized by intra-molecular C-H⋯O hydrogen bonds, which generate S(6) and S(9) ring motifs. The chloro-form solvent mol-ecule is linked to the organic mol-ecule by a C-H⋯O hydrogen bond involving the carbonyl O atom of the carboxyl-ate group. In the crystal, mol-ecules are linked via bifurcated N-H⋯(N,O) and C-H⋯O hydrogen bonds, forming chains propagating along [001].

4-(4-Bromo-phen-yl)-2-methyl-amino-3-nitro-5,6,7,8-tetra-hydro-4H-chromen-5-one.

In the title compound, C16H15BrN2O4, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the disordered methyl-ene C atom as the flap. The pyran ring is almost orthogonal to the chloro-phenyl ring, making a dihedral angle of 87.11 (12)°. The amine-group N atom deviates significantly from the pyran ring [0.238 (3) Å]. The mol-ecular structure is stabilized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, which generate C(8) chains running parallel to the b axis. The chains are linked by C-H⋯π inter-actions. The methyl-ene-group C atom of the chromene system that is disordered, along with its attached H atoms and the H atoms on the two adjacent C atoms, has an occupancy ratio of 0.791 (7):0.209 (7).

(4S*)-2-Methyl-amino-3-nitro-4-(4-nitro-phen-yl)-5,6,7,8-tetra-hydro-4H-chromen-5-one.

The title compound, C16H15N3O6, is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The six-membered carbocyclic ring adopts an envelope conformation with the central CH2 C atom as the flap. The amine N atom deviates from the mean plane of the pyran ring by 0.1365 (15) Å. The nitro-phenyl ring is almost orthogonal to the pyran ring and the mean plane of the six-membered carbocyclic ring, the dihedral angle between their mean planes being 88.30 (7) and 87.61 (8)°, respectively. The mol-ecular structure is stabilized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming infinite bands lying parallel to (-110) and composed of alternate R 2 (2)(24) and R 2 (4)(12) graph-set ring motifs. The crystal structure is further stabilized by C-H⋯π inter-actions, forming a three-dimensional structure.