Calibration-free infrared absorption spectroscopy using cantilever-enhanced photoacoustic detection of the optical power.

We report on sensitive tunable laser absorption spectroscopy using a multipass gas cell and a solid-state photoacoustic optical power detector. Unlike photoacoustic spectroscopy (PAS), this method readily allows a low gas pressure for high spectral selectivity and a free gas flow for continuous measurements. Our photoacoustic optical power detector has a large linear dynamic range and can be used at almost any optical wavelength, including the middle infrared and THz regions that are challenging to cover with traditional optical detectors.

Recovery of short-chain organic acids (SCOAs) obtained from anaerobic fermentation process.

Short-chain organic acids (SCOAs) are the intermediates in the anaerobic fermentation process, and can be used in food, textile, and pharmaceutical industries to produce different end use products. SCOAs can be separated, purified, and concentrated by different processes, such as distillation, extraction or membrane-based systems. SCOAs production adds more profitable possibilities to an acidic fermentation process by integration these marketable acids as highly concentrated mixtures with other refinery processes.

Reference-free dual-comb spectroscopy with inbuilt coherence: publisher's note.

This publisher's note contains a correction to Opt. Lett.49, 2473 (2024)10.

High-Pitched Sound is Open and Low-Pitched Sound is Closed: Representing the Spatial Meaning of Pitch Height.

Research shows that high- and low-pitch sounds can be associated with various meanings. For example, high-pitch sounds are associated with small concepts, whereas low-pitch sounds are associated with large concepts. This study presents three experiments revealing that high-pitch sounds are also associated with open concepts and opening hand actions, while low-pitch sounds are associated with closed concepts and closing hand actions.

Is Front associated with Above and Back with Below? Association between Allocentric Representations of Spatial Dimensions.

Previous research has revealed congruency effects between different spatial dimensions such as right and up. In the audiovisual context, high-pitched sounds are associated with the spatial dimensions of up/above and front, while low-pitched sounds are associated with the spatial dimensions of down/below and back. This opens the question of whether there could also be a spatial association between above and front and/or below and back.

Reference-free dual-comb spectroscopy with inbuilt coherence.

We demonstrate a simple system for dual-comb spectroscopy based on two inherently coherent optical frequency combs generated via seeded parametric downconversion. The inbuilt coherence is established by making the two combs share a common comb line. We show that the inbuilt coherence makes it possible to use a simple numerical post-processing procedure to compensate for small drifts of the dual-comb interferogram arrival time and phase.

Sound symbolism in manual and vocal responses: phoneme-response interactions associated with grasping as well as vertical and size dimensions of keypresses.

It has been shown that reading the vowel [i] and consonant [t] facilitates precision grip responses, while [ɑ] and [k] are associated with faster power grip responses. A similar effect has been observed when participants perform responses with small or large response keys. The present study investigated whether the vowels and consonants could produce different effects with the grip responses and keypresses when the speech units are read aloud (Experiment 1) or silently (Experiment 2).

Front Is High and Back Is Low: Sound-Space Iconicity in Finnish.

Previous investigations have shown various interactions between spatial concepts and speech sounds. For instance, the front-high vowel [i] is associated with the concept of forward, and the back-high vowel [o] is associated with the concept of backward. Three experiments investigated whether the concepts of forward/front and backward/back are associated with high- and low-pitched vocalizations, respectively, in Finnish.

Anaerobic Digestion of Solid Agricultural Biomass in Leach-Bed Reactors.

This study focuses on the feasibility of the dry anaerobic digestion of solid agricultural biomass for efficient renewable-energy production and nutrient recycling. Methane production and the amount of nitrogen in the digestates were measured in pilot- and farm-scale leach-bed reactors. In the pilot scale, with a digestion time of 133 days, the methane production of a mixture of whole crop fava bean and horse manure corresponded to 94% and 116%, respectively, of the methane potentials of the solid substrates.

Sound-action symbolism in relation to precision manipulation and whole-hand grasp usage.

It has been suggested that actions can provide a fruitful conceptual context for sound symbolism phenomena, and that tight interaction between manual and articulatory processes might cause that hand actions, in particular, are sound-symbolically associated with specific speech sounds. Experiment 1 investigated whether novel words, built from speech sounds that have been previously linked to precision or power grasp responses, are implicitly associated with perceived actions that present precision manipulation or whole-hand grasp tool-use or the corresponding utilisation pantomimes. In the two-alternative forced-choice task, the participants were more likely to match novel words to tool-use actions and corresponding pantomimes that were sound-symbolically congruent with the words.

Terahertz radiation detection with a cantilever-based photoacoustic sensor.

We report the photoacoustic (PA) response in the terahertz (THz) range by employing a detection process actuated with a silicon cantilever pressure sensor and a carbon-based radiation absorber. The detection relies on the mechanical response of the cantilever, when the volume of the carrier gas inside the PA cell expands with the heat produced by the radiation absorber. The detector interferometrically monitors the movement of the cantilever sensor to generate the PA signal.

Versatile optical frequency combs based on multi-seeded femtosecond optical parametric generation.

This study proposes and demonstrates a versatile method for near- and mid-infrared optical frequency comb generation using multi-seeded femtosecond optical parametric generation. The method allows one to divide the repetition rate by an arbitrarily large integer factor, freely tune the offset frequency, and adjust the common phase offset of the comb modes. Since all possible degrees of freedom are adjustable, the proposed method manifests itself as versatile optical frequency synthesis.

Auditory-perceptual evaluation with visual analogue scale: feasibility and preliminary evidence of ultrasound visual feedback treatment of Finnish [r].

Accumulating evidence suggests that ultrasound visual feedback increases the treatment efficacy for persistent speech sound errors. However, the available evidence is mostly from English. This is a feasibility study of ultrasound visual feedback for treating distortion of Finnish [r].

Nonclinical Characterization of Bexmarilimab, a Clever-1-Targeting Antibody for Supporting Immune Defense Against Cancers.

Common lymphatic endothelial and vascular endothelial receptor-1 (Clever-1) is a multifunctional type-1 transmembrane protein that plays an important role in immunosuppression against tumors. Clever-1 is highly expressed in a subset of human tumor-associated macrophages and associated with poor survival. In mice, Clever-1 supports tumor growth and metastasis formation, and its deficiency or blockage induces T-cell-dependent killing of cancer cells.

Optical power detector with broad spectral coverage, high detectivity, and large dynamic range.

Optical power measurements are needed in practically all technologies based on light. Here, we report a general-purpose optical power detector based on the photoacoustic effect. Optical power incident on the detector's black absorber produces an acoustic signal, which is further converted into an electrical signal using a silicon-cantilever pressure transducer.

Interaction between grasping and articulation: How vowel and consonant pronunciation influences precision and power grip responses.

Grasping and mouth movements have been proposed to be integrated anatomically, functionally and evolutionarily. In line with this, we have shown that there is a systematic interaction between particular speech units and grip performance. For example, when the task requires pronouncing a speech unit simultaneously with grasp response, the speech units [i] and [t] are associated with relatively rapid and accurate precision grip responses, while [ɑ] and [k] are associated with power grip responses.

Changes in volatile fatty acid production and microbiome during fermentation of food waste from hospitality sector.

Due to the increasing demand for low carbon-footprint bioproducts in the markets, innovative processes technologies and products are needed. The objective of this study was to assess the quality and potential of food waste (FW) from the hospitality sector to produce volatile fatty acids (VFAs). A batch type acid fermentation system was used to study VFA production in different process conditions (a decreased pH and increased organic loading rate).

Sound-Action Symbolism.

Recent evidence has shown linkages between actions and segmental elements of speech. For instance, close-front vowels are sound symbolically associated with the precision grip, and front vowels are associated with forward-directed limb movements. The current review article presents a variety of such sound-action effects and proposes that they compose a category of sound symbolism that is based on grounding a conceptual knowledge of a referent in articulatory and manual action representations.

LED-Based Photoacoustic NO Sensor with a Sub-ppb Detection Limit.

A high-sensitivity light-emitting diode (LED)-based photoacoustic NO sensor is demonstrated. Sensitive photoacoustic gas sensors based on incoherent light sources are typically limited by background noise and drifts due to a strong signal generated by light absorbed at the photoacoustic cell walls. Here, we reach a sub-ppb detection limit and excellent stability using cantilever-enhanced photoacoustic detection and perform a two-channel relative measurement.

Mid-infrared frequency comb with 25 pJ threshold via CW-seeded optical parametric generation in nonlinear waveguide.

We demonstrate efficient generation of mid-infrared frequency combs based on continuous-wave-seeded femtosecond optical parametric generation in nonlinear waveguides. Conversion of the near-infrared pump to signal and idler light takes place with very high efficiency (74%), and the threshold (25 pJ for 100 fs pulses) is over 300 times lower than in bulk analogs. Relative intensity noise of the mid-infrared comb is exceptionally low, below 5×10 (integrated from 10 Hz to 2 MHz).

Photoacoustic characteristics of carbon-based infrared absorbers.

We present an experimental comparison of photoacoustic responsivities of common highly absorbing carbon-based materials. The comparison was carried out with parameters relevant for photoacoustic power detectors and Fourier-transform infrared (FTIR) spectroscopy: we covered a broad wavelength range from the visible red to far infrared (633 nm to 25 μm) and the regime of low acoustic frequencies (< 1 kHz). The investigated materials include a candle soot-based coating, a black paint coating and two different carbon nanotube coatings.

Radiocarbon dioxide detection using cantilever-enhanced photoacoustic spectroscopy.

In this Letter, we report on the sub-parts-per-billion-level radiocarbon dioxide detection using cantilever-enhanced photoacoustic spectroscopy. The / ratio of samples is measured by targeting a absorption line with minimal interference from other isotopes. Using a quantum cascade laser as a light source allows for a compact experimental setup.

Broadband Laser-Based Infrared Detector for Gas Chromatography.

Cantilever-enhanced photoacoustic spectroscopy coupled with gas chromatography is used to quantitatively analyze a mixture of alcohols in a quasi-online manner. A full identification and quantification of all analytes are achieved based on their spectral fingerprints using a widely tunable continuous-wave laser as a light source. This can be done even in the case of interfering column/septum bleed or simultaneously eluted peaks.

Missing-in-Metastasis/Metastasis Suppressor 1 Regulates B Cell Receptor Signaling, B Cell Metabolic Potential, and T Cell-Independent Immune Responses.

Efficient generation of antibodies by B cells is one of the prerequisites of protective immunity. B cell activation by cognate antigens via B cell receptors (BCRs), or pathogen-associated molecules through pattern-recognition receptors, such as Toll-like receptors (TLRs), leads to transcriptional and metabolic changes that ultimately transform B cells into antibody-producing plasma cells or memory cells. BCR signaling and a number of steps downstream of it rely on coordinated action of cellular membranes and the actin cytoskeleton, tightly controlled by concerted action of multiple regulatory proteins, some of them exclusive to B cells.

Dialectal variation of duration patterns in Finnmark North Sámi quantity.

Ternary length contrast is a rare phonological feature, investigated here both in terms of its realization and possible undergoing changes. In North Sámi, a phonetically under-documented and endangered Fenno-Ugric language spoken by indigenous people in Northern Europe, the ternary quantity contrast is assumed to be signalled by a progressive lengthening of a consonant and a compensatory shortening of the previous vowel. This study evaluates this assumption and compares the realization of the length contrasts in two dialects, the Western and Eastern Finnmark North Sámi.