The working alliance inventory - short version: psychometric properties of the patient and therapist form in youth mental health and addiction care.

The therapeutic alliance is considered to play an important role in youth treatment. The commonly used versions of the Working Alliance Inventory (WAI) are based on Bordin's three-dimensional alliance model. However, previous psychometric studies of the WAI did not find this three-dimensional structure in youth psychotherapy. These earlier findings may indicate different perceptions of the alliance by adolescent versus adult patients, but may also be due to methodological shortcomings. The current study aims to address previous study limitations by evaluating the factor structure of the short version of the WAI (WAI-S) in youth treatment in multilevel analysis to address the hierarchical structure of the alliance data. We examined the psychometric properties of the patient (n = 203) and therapist (n = 62) versions of the WAI-S in youth mental health and addiction care and tested four multilevel models of alliance at start of treatment and 2-month follow-up. Our results suggests a two-factor model for youth and a three-dimensional model for their therapist at both time points. Since this is the first study that finds a best fit for a two-dimensional construct of alliance in youth, more research is needed to clarify whether the differences in alliance dimensions are due to measurement differences between the WAI-S for youth and therapists or whether youth and their therapists truly differ in their perceptions of the concept of alliance.

Steroid responsiveness predicts olfactory function recovery in dupilumab treated CRSwNP.

BACKGROUND: There is no known predictor for olfactory function recovery with dupilumab treatment in chronic rhinosinusitis with nasal polyps (CRSwNP). This study assessed whether patient-reported recovery of olfactory function on oral corticosteroids (OCS) is a prognostic factor. METHODS: Retrospective analysis of pre-biological OCS-responsiveness on olfactory functioning (OCS-responsive or OCS-unresponsive; OCS-r and OCR-u, respectively) as predictor for olfactory functioning after 6 months of dupilumab therapy for severe CRSwNP. RESULTS: 212 CRSwNP patients treated with dupilumab were divided between OCS-r (reported improvement of olfactory function with OCS before dupilumab treatment, n = 152), and OCS-u (OCS-unresponsive; no such improvement, n = 60). Olfactory function was tested with Sniffin' Sticks Identification Test (12 pens; SSIT-12). At baseline, both groups had a median SSIT-12 score of 3 / 12 indicating anosmia. Hyposmia and normosmia rates were also comparable (5.9% and 3.3% in OCS-r, respectively; 5.0% and 1.7% in OCS-u, respectively). After 6 months of dupilumab treatment, OCS-r showed higher olfactory scores (median SSIT-12: 8/12; 52.6% hyposmia and 17.8% normosmia) than OCS-u (median SSIT-12: 5/12; 31.7% hyposmia and 3.3% normosmia). The positive predictive value of OCS-responsiveness on scoring ≥7 (normosmia/hyposmia) on the SSIT-12 after 6 months of dupilumab treatment was 70.4%. Conversely, the negative predictive value of OCS-unresponsiveness on scoring.

Eosinophils are the dominant type2 marker for the current indication of biological treatment in severe uncontrolled chronic rhinosinusitis with nasal polyps.

The latest European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS2020) defines markers for type2 inflammation in the context of indicating biological therapy in severe uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP) as either a total serum immunoglobulin E (total-IgE) <100 kU/L, a blood eosinophil count (BEC, expressed as -109 cells / L) >=0.25, or a tissue eosinophil count >=10 per high power field (HPF) (1). Recently, an EPOS/EUFOREA expert panel advised to lower the threshold for BEC from >=0.25 (EPOS2020) to >=0.15 (EUFOREA2023) to align with thresholds used for biological indication in asthma patients (2). As far as we know, there is no literature supporting the cut-off value for total-IgE.

Hypereosinophilia during dupilumab treatment in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Increased blood eosinophil count (BEC) is common in patients under dupilumab treatment for chronic rhinosinusitis with nasal polyps (CRSwNP). This study investigated the prevalence and consequences of hypereosinophilia and to help define patients at risk. METHODS: Real-life, prospective observational cohort study of patients treated with dupilumab for severe CRSwNP. Eligible patients were adult and biological-naive (N=334). All BEC values at baseline and during treatment were reported. Patients with a follow-up of >= 1 year were included to define patients at risk for hypereosinophilia by comparing baseline BEC values (N=218). Furthermore, clinical characteristics and therapeutic consequences for patients with BEC >= 3.0 were noted. RESULTS: Hypereosinophilia developed in a minority of patients, with a peak at week 12 (16.2% with BEC >= 1.5, and 1.7% >= 3.0) in cross-sectional analysis. BEC >= 1.5 developed in 28.9% and BEC >=3.0 in 4.6% of cases with a minimal 1-year follow-up. Baseline BEC was significantly higher for patients developing BEC >= 1.5 and BEC >=3.0, with an optimal cut-off point of 0.96 to predict developing BEC >= 3.0. CONCLUSIONS: Blood eosinophil count (BEC) >= 1.5 is transient and usually abates with no therapeutic interventions and BEC >= 3.0 is rare. Hypereosinophilic syndrome did not occur and switching to a different biological was rarely employed. A baseline BEC of >=1.0 can be a reason for extra caution.

Training is not enough: child and adolescent psychiatry clinicians' impressions of telepsychiatry during the first COVID-19 related lockdown.

To ensure the continuity of care during the COVID-19 pandemic, clinicians in Child and Adolescent Psychiatry (CAP) were forced to immediately adapt in-person treatment into remote treatment. This study aimed to examine the effects of pre-COVID-19 training in- and use of telepsychiatry on CAP clinicians' impressions of telepsychiatry during the first two weeks of the Dutch COVID-19 related lockdown, providing a first insight into the preparations necessary for the implementation and provision of telepsychiatry during emergency situations. All clinicians employed by five specialized CAP centres across the Netherlands were invited to fill in a questionnaire that was specifically developed to study CAP clinicians' impressions of telepsychiatry during the COVID-19 pandemic. A total of 1065 clinicians gave informed consent and participated in the study. A significant association was found between pre-COVID-19 training and/or use of telepsychiatry and CAP clinicians' impressions of telepsychiatry. By far, the most favourable impressions were reported by participants that were both trained and made use of telepsychiatry before the pandemic. Participants with either training or use separately reported only slightly more favourable impressions than participants without any previous training or use. The expertise required to provide telepsychiatry is not one-and-the-same as the expertise that is honed through face-to-face consultation. The findings of this study strongly suggest that, separately, both training and (clinical) practice fail to sufficiently support CAP clinicians in the implementation and provision of telepsychiatry. It is therefore recommended that training and (clinical) practice are provided in conjunction.

Sociodemographic and clinical characteristics in child and youth mental health; comparison of routine outcome measurements of an Australian and Dutch outpatient cohort.

AIMS: Although of great value to understand the treatment results for mental health problems obtained in clinical practice, studies using naturalistic data from children and adolescents seeking clinical care because of complex mental health problems are limited. Cross-national comparison of naturalistic outcomes in this population is seldomly done. Although careful consideration is needed, such comparisons are likely to contribute to an open dialogue about cross-national differences and may stimulate service improvement. The aim of this observational study is to investigate clinical characteristics and outcomes in naturalistic cohorts of specialized child and adolescent mental health outpatient care in two different countries. METHODS: Routinely collected data from 2013 to 2018 of 2715 outpatients in the Greater Area of Brisbane, Australia (CYMHS) and 1158 outpatients in Leiden, the Netherlands (LUMC-Curium) were analysed. Demographics, clinical characteristics and severity of problems at start and end of treatment were described, using Children's Global Assessment Scale (CGAS), Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA) and the parental Strength and Difficulties Questionnaire (SDQ-P). RESULTS: Routine outcome measures (CGAS, HoNOSCA, SDQ-P) showed moderate to severe mental health problems at start of treatment, which improved significantly over time in both cohorts. Effect sizes ranged between 0.73-0.90 (CYMHS) and 0.57-0.76 (LUMC-Curium). While internalizing problems (mood disorder, anxiety disorder and stress-related disorder) were more prevalent at CYMHS, externalizing developmental problems (ADHD, autism) prevailed at LUMC-Curium. Comorbidity (>1 diagnosis on ICD10/DSM-IV) was relatively similar: 45% at CYMHS and 39 % at LUMC-Curium. In both countries, improvement of functioning was lowest for conduct disorder and highest for somatoform/conversion disorders and obsessive-compulsive disorders (OCD). Overall, 20-40% showed clinically significant improvement (shift from clinical-range at start to a non-clinical-range at the end of treatment), but nearly half of patients still experienced significant symptoms at discharge. CONCLUSIONS: This large-scale outcome study showed both cohorts from Australia and the Netherlands improve during the course of treatment on clinician- and parent-reported measures. Although samples were situated within different contexts and differed in patient profiles, they showed similar trends in improvement per diagnostic group. While 20-40% showed clinically significant change, many patients experienced residual symptoms reflecting increased risk for negative outcome into adulthood. We emphasize cross-national comparison of naturalistic outcomes faces challenges, although it can similarly reveal trends in treatment outcome providing direction for future research: what factors determine discharge from specialized services; and how to improve current treatments in this severely affected population.

Management and outcome of middle ear adenomatous neuroendocrine tumours: A systematic review.

Middle ear adenomatous neuroendocrine tumours (MEANTs) are rare, unpredictable tumours. Although most MEANTs are characterized by a benign biological behaviour and indolent growth pattern, some studies have reported locally invasive and metastastic disease. Currently, the optimal management strategy for MEANTs remains subject of debate. The aim of this study is to review the literature on MEANTs with focus on its clinical characteristics, treatment strategies and outcome. A systematic review was conducted using PubMed, Embase and Cochrane databases. A total of 111 studies comprising 198 patients with MEANT were included. Treatment modalities comprised surgery (90%), surgery with adjuvant radiotherapy (9%) and palliative (chemo)radiotherapy in (1%). Local recurrence was observed in 25% of the patients and 7% of the patients developed metastasis, over a median period of 5.7 years (range 7 months - 32 years). Twelve of 13 patients (92%) who developed metastases had a local recurrence. Four patients (2%) died of MEANT: three due to distant metastases and one due to extensive local recurrence. Reliable histopathologic predictors of outcome could not be identified. These findings indicate that the clinical presentations of MEANT vary substantially, the overall recurrence rate is considerable and initial local tumour control is paramount. Because of the unpredictable clinical course, prolonged follow-up is warranted.

Temperature and salt effects on settling velocity in granular sludge technology.

Settling velocity is a crucial parameter in granular sludge technology. In this study the effects of temperature and salt concentrations on settling velocities of granular sludge particles were evaluated. A two-fold slower settling velocity for the same granules was observed when the temperature of water decreases from 40 °C to 5 °C. Settling velocities also decreased with increasing salt concentrations. Experiments showed that when granules were not pre-incubated in a solution with increased salt concentration, they initially floated. The time dependent increase in mass and hence in settling speed of a granule due to salt diffusion into the granule was dependent on the granule diameter. The time needed for full salt equilibrium with the bulk liquid took 1 min for small particles from the top of the sludge bed and up to 30 min for big granules from the bottom of the sludge bed. These results suggest that temperature and salt concentration are important parameters to consider in the design, start-up and operation of granular sludge reactors and monitoring of these parameters will aid in a better control of the sludge management in anaerobic and aerobic granular sludge technology. The observations also give an explanation for previous reports which were suggesting that a start-up of granular sludge reactors is more difficult at low temperatures.

Temperature and salt effects on settling velocity in granular sludge technology.

Settling velocity is a crucial parameter in granular sludge technology. In this study the effects of temperature and salt concentrations on settling velocities of granular sludge particles were evaluated. A two-fold slower settling velocity for the same granules where observed when the temperature of water decreases from 40 °C to 5 °C. Settling velocities also decreased with increasing salt concentrations. Experiments showed that when granules were not pre-incubated in a solution with increased salt concentration, they initially floated. The time dependent increase in mass and hence in settling speed of a granule due to salt diffusion into the granule was dependent on the granule diameter. The time needed for full salt equilibrium with the bulk liquid took 1 min for small particles from the top of the sludge bed and up to 30 min for big granules from the bottom of the sludge bed. These results suggest that temperature and salt concentration are important parameters to consider in the design, start-up and operation of granular sludge reactors and monitoring of these parameters will aid in a better control of the sludge management in anaerobic and aerobic granular sludge technology. The observations also give an explanation for previous reports which were suggesting that a start-up of granular sludge reactors is more difficult at low temperatures.

Strategy for selection of methods for separation of bioparticles from particle mixtures.

The desired product of bioprocesses is often produced in particulate form, either as an inclusion body (IB) or as a crystal. Particle harvesting is then a crucial and attractive form of product recovery. Because the liquid phase often contains other bioparticles, such as cell debris, whole cells, particulate biocatalysts or particulate by-products, the recovery of product particles is a complex process. In most cases, the particulate product is purified using selective solubilization or extraction. However, if selective particle recovery is possible, the already high purity of the particles makes this downstream process more favorable. This work gives an overview of typical bioparticle mixtures that are encountered in industrial biotechnology and the various driving forces that may be used for particle-particle separation, such as the centrifugal force, the magnetic force, the electric force, and forces related to interfaces. By coupling these driving forces to the resisting forces, the limitations of using these driving forces with respect to particle size are calculated. It shows that centrifugation is not a general solution for particle-particle separation in biotechnology because the particle sizes of product and contaminating particles are often very small, thus, causing their settling velocities to be too low for efficient separation by centrifugation. Examples of such separation problems are the recovery of IBs or virus-like particles (VLPs) from (microbial) cell debris. In these cases, separation processes that use electrical forces or fluid-fluid interfaces show to have a large potential for particle-particle separation. These methods are not yet commonly applied for large-scale particle-particle separation in biotechnology and more research is required on the separation techniques and on particle characterization to facilitate successful application of these methods in industry.

Quantification of solid cell material by detection of membrane-associated proteins and peptidoglycan.

Quantification of solid cell material (cell debris) is necessary for the optimisation of the efficiency of bioseparations. Cell debris can be quantified by detection of a component present in the cell wall that can act as a marker for cell debris. Membrane-associated proteins have previously been used as a marker for cell debris. This marker was quantified by SDS-PAGE with densiometry. In this paper cell debris quantification methods are presented that are faster and more accurate, i.e. membrane-associated protein quantification with the Protein 50 Labchip of Agilent Technologies, or that make use of peptidoglycan as marker for cell debris, i.e. a spectrophotometric muramic acid assay.

Recovery of small bioparticles by interfacial partitioning.

In this article, a qualitative study of the recovery of small bioparticles by interfacial partitioning in liquid-liquid biphasic systems is presented. A range of crystallised biomolecules with varying polarities have been chosen such as glycine, phenylglycine and ampicillin. Liquid-liquid biphasic systems in a range of polarity differences were selected such as an aqueous two-phase system (ATPS), water-butanol and water-hexanol. The results indicate that interfacial partitioning of crystals occurs even when their density exceeds that of the individual liquid phases. Yet, not all crystals partition to the same extent to the interface to form a stable and thick interphase layer. This indicates some degree of selectivity. From the analysis of these results in relation to the physicochemical properties of the crystals and the liquid phases, a hypothetical mechanism for the interfacial partitioning is deduced. Overall these results support the potential of interfacial partitioning as a large scale separation technology.

Physiological responses to mixing in large scale bioreactors.

Escherichia coli fed-batch cultivations at 22 m3 scale were compared to corresponding laboratory scale processes and cultivations using a scale-down reactor furnished with a high-glucose concentration zone to mimic the conditions in a feed zone of the large bioreactor. Formate accumulated in the large reactor, indicating the existence of oxygen limitation zones. It is suggested that the reduced biomass yield at large scale partly is due to repeated production/re-assimilation of acetate from overflow metabolism and mixed acid fermentation products due to local moving zones with oxygen limitation. The conditions that generated mixed-acid fermentation in the scale-down reactor also induced a number of stress responses, monitored by analysis of mRNA of selected stress induced genes. The stress responses were relaxed when the cells returned to the substrate limited and oxygen sufficient compartment of the reactor. Corresponding analysis in the large reactor showed that the concentration of mRNA of four stress induced genes was lowest at the sampling port most distant from the feed zone. It is assumed that repeated induction/relaxation of stress responses in a large bioreactor may contribute to altered physiological properties of the cells grown in large-scale bioreactor. Flow cytometric analysis revealed reduced damage with respect to cytoplasmic membrane potential and integrity in cells grown in the dynamic environments of the large scale reactor and the scale-down reactor.

Effects of dissolved oxygen tension and mechanical forces on fungal morphology in submerged fermentation.

The effects of dissolved oxygen tension and mechanical forces on fungal morphology were both studied in the submerged fermentation of Aspergillus awamori. Pellet size, the hairy length of pellets, and the free filamentous mycelial fraction in the total biomass were found to be a function of the mechanical force intensity and to be independent of the dissolved oxygen tension provided that the dissolved oxygen tension was neither too low (5%) nor too high (330%). When the dissolved oxygen concentration was close to the saturation concentration corresponding to pure oxygen gas, A. awamori formed denser pellets and the free filamentous mycelial fraction was almost zero for a power input of about 1 W/kg. In the case of very low dissolved oxygen tension, the pellets were rather weak and fluffy so that they showed a very different appearance. The amount of biomass per pellet surface area appeared to be affected only by the dissolved oxygen tension and was proportional to the average dissolved oxygen tension to the power of 0.33. From this it was concluded that molecular diffusion was the dominant mechanism for oxygen transfer in the pellets and that convection and turbulent flow in the pellets were negligible in submerged fermentations. The biomass per wet pellet volume increased with the dissolved oxygen tension and decreased with the size of the pellets. This means that the smaller pellets formed under a higher dissolved oxygen tension had a higher intrinsic strength. Correspondingly, the porosity of the pellets was a function of the dissolved oxygen tension and the size of pellets. Within the studied range, the void fraction in the pellets was high and always much more than 50%.

Modeling and measurements of fungal growth and morphology in submerged fermentations.

Generalizing results from fungal fermentations is difficult due to their high sensitivity toward slight variation in starting conditions, poor reproducibility, and difference in strains. In this study a mathematical model is presented in which oxygen transfer, agitation intensity, dissolved oxygen tension, pellet size, formation of mycelia, the fraction of mycelia in the total biomass, carbohydrate source consumption, and biomass growth are taken into account. Two parameters were estimated from simulation, whereas all others are based on measurements or were taken from literature. Experimental data are obtained from the fermentations in both 2 L and 100 L fermentors at various conditions. Comparison of the simulation with experiments shows that the model can fairly well describe the time course of fungal growth (such as biomass and carbohydrate source concentrations) and fungal morphology (such as pellet size and the fraction of pellets in the total biomass). The model predicts that a stronger agitation intensity leads to a smaller pellet size and a lower fraction of pellets in the total biomass. At the same agitation intensity, pellet size is hardly affected by the dissolved oxygen tension, whereas the fraction of mycelia decreases slightly with an increase of the dissolved oxygen tension in the bulk. All of these are in line with observations at the corresponding conditions.

Hydrodynamic characteristics and gas-liquid mass transfer in a biofilm airlift suspension reactor.

The hydrodynamics and mass transfer, specifically the effects of gas velocity and the presence and type of solids on the gas hold-up and volumetric mass transfer coefficient, were studied on a lab-scale airlift reactor with internal draft tube. Basalt particles and biofilm-coated particles were used as solid phase. Three distinct flow regimes were observed with increasing gas flow rate. The influence of the solid phase on the hydrodynamics was a peculiar characteristic of the regimes. The volumetric mass transfer coefficient was found to decrease with increasing solid loading and particle size. This could be predominantly related to the influence that the solid has on gas hold-up. The ratio between gas hold-up and volumetric mass transfer coefficient was found to be independent of solid loading, size, or density, and it was proven that the presence of solids in airlift reactors lowers the number of gas bubbles without changing their size. To evaluate scale effects, experimental results were compared with theoretical and empirical models proposed for similar systems.

Effect of agitation intensities on fungal morphology of submerged fermentation.

Both parallel fermentations with Aspergillus awamori (CBS 115.52) and a literature study on several fungi have been carried out to determine a relation between fungal morphology and agitation intensity. The studied parameters include hyphal length, pellet size, surface structure or so-called hairy length of pellets, and dry mass per-wet-pellet volume at different specific energy dissipation rates. The literature data from different strains, different fermenters, and different cultivation conditions can be summarized to say that the main mean hyphal length is proportional to the specific energy dissipation rate according to a power function with an exponent of -0.25 +/- 0.08. Fermentations with identical inocula showed that pellet size was also a function of the specific energy dissipation rate and proportional to the specific energy dissipation rate to an exponent of -0.16 +/- 0.03. Based on the experimental observations, we propose the following mechanism of pellet damage during submerged cultivation in stirred fermenters. Interaction between mechanical forces and pellets results in the hyphal chip-off from the pellet outer zone instead of the breakup of pellets. By this mechanism, the extension of the hyphae or hair from pellets is restricted so that the size of pellets is related to the specific energy dissipation rate. Hyphae chipped off from pellets contribute free filamentous mycelia and reseed their growth. So the fraction of filamentous mycelial mass in the total biomass is related to the specific energy dissipation rate as well.To describe the surface morphology of pellets, the hyphal length in the outer zone of pellets or the so-called hairy length was measured in this study. A theoretical relation of the hairy length with the specific energy dissipation rate was derived. This relation matched the measured data well. It was found that the porosity of pellets showed an inverse relationship with the specific energy dissipation rate and that the dry biomass per-wet-pellet volume increased with the specific energy dissipation rates. This means that the tensile strength of pellets increased with the increase of specific energy dissipation rate. The assumption of a constant tensile strength, which is often used in literature, is then not valid for the derivation of the relation between pellet size and specific energy dissipation rate. The fraction of free filamentous mycelia in the total biomass appeared to be a function of the specific energy dissipation in stirred bioreactors. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 715-726, 1997.

Quantification of brewers' yeast flocculation in a stirred tank: effect of physical parameters on flocculation.

Quantification of yeast flocculation under defined conditions will help to understand the physical mechanisms of the flocculation process used in beer fermentation. Flocculation was quantified by measuring the size of yeast flocs and the number of single cells. For this purpose, a method to measure floc size and number of single cells in situ was developed. In this way, it was possible to quantify the actual flocculation during fermentation, without influencing flocculation. The effects of three physical parameters, floc strength, fluid shear, and yeast cell concentration, on flocculation during beer fermentation, were examined. Increasing floc strength results in larger flocs and lower numbers of single cells. If the fluid shear is increased, the size of the flocs decreases, and the number of single cells remains constant at approximately 10% of the total cells present. The cell concentration also influences flocculation, a reduction of 50% in cell concentration leads to a decrease of about 25% in floc size. The number of single cells decreases in linear proportion to the cell concentration. This means that, during yeast settling at full scale, the number of single cells decreases. The results of this study are used in a model for yeast flocculation. With respect to full scale fermentation the effect of cell concentration will play an important role, for flocculation and sedimentation will occur simultaneously leading to a quasi steady state between these phenomena. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 190-200, 1997.

Oxygen and carbon dioxide mass transfer and the aerobic, autotrophic cultivation of moderate and extreme thermophiles: a case study related to the microbial desulfurization of coal.

Mass transfers of O(2), CO(2), and water vapor are among the key processes in the aerobic, autotrophic cultivation of moderate and extreme thermophiles. The dynamics and kinetics of these processes are, in addition to the obvious microbial kinetics, of crucial importance for the industrial desulfurization of high-pyritic coal by such thermophiles. To evaluate the role of the temperature on the gas mass transfer, k(L)a measurements have been used to supplement the existing published data. Oxygen mass transfer from gas (air) to liquid (5 mM H(2)SO(4) in water) phase as a function of the temperature has been studied in a laboratory-scale fermentor. At 15, 30, 45, and 70 degrees C, (k(L)a)(o) values (for oxygen) were determined under three different energy input conditions by the dynamic gassing in/out method. The (k(L)a)(o) was shown to increase under these conditions with increasing temperature, and straight lines were obtained when the logarithm of (k(L)a)(o) was plotted against the temperature. By multiplying the equilibrium concentration of O(2) in water with (k(L)a)(o) maximal, O(2) transfer capacities were calculated. It appeared that in finite of a decreased solubility of O(2) at elevated temperature in mechanically mixed fermentors the calculated transfer capacities showed only minor changes for the range between 15 and 70 degrees C. However, in an air-mixed fermentor the transfer capacity of O(2) decreased slowly but steadily.Carbon dioxide mass transfer was predicted by calculations on the basis of the data for oxygen transfer. The maximal CO(2) transfer capacity, calculated as the product of the equilibrium CO(2) concentration times (k(L)a)(c), decreased slowly as the temperature increased over the range 15-70 degrees C under all three energy input conditions. Subsequent process design calculations showed that for aerobic, autotrophic cultures, CO(2) limitation is more likely to occur than O(2) limitation.