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Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
This study explored mental workload recognition methods for carrier-based aircraft pilots utilising multiple sensor physiological signal fusion and portable devices. A simulation carrier-based aircraft flight experiment was designed, and subjective mental workload scores and electroencephalogram (EEG) and photoplethysmogram (PPG) signals from six pilot cadets were collected using NASA Task Load Index (NASA-TLX) and portable devices. The subjective scores of the pilots in three flight phases were used to label the data into three mental workload levels. Features from the physiological signals were extracted, and the interrelations between mental workload and physiological indicators were evaluated. Machine learning and deep learning algorithms were used to classify the pilots’ mental workload. The performances of the single-modal method and multimodal fusion methods were investigated. The results showed that the multimodal fusion methods outperformed the single-modal methods, achieving higher accuracy, precision, recall and F1 score. Among all the classifiers, the random forest classifier with feature-level fusion obtained the best results, with an accuracy of 97.69%, precision of 98.08%, recall of 96.98% and F1 score of 97.44%. The findings of this study demonstrate the effectiveness and feasibility of the proposed method, offering insights into mental workload management and the enhancement of flight safety for carrier-based aircraft pilots.
Blast injuries can occur by a multitude of mechanisms, including improvised explosive devices (IEDs), military munitions, and accidental detonation of chemical or petroleum stores. These injuries disproportionately affect people in low- and middle-income countries (LMICs), where there are often fewer resources to manage complex injuries and mass-casualty events.
Study Objective:
The aim of this systematic review is to describe the literature on the acute facility-based management of blast injuries in LMICs to aid hospitals and organizations preparing to respond to conflict- and non-conflict-related blast events.
Methods:
A search of Ovid MEDLINE, Scopus, Global Index Medicus, Web of Science, CINAHL, and Cochrane databases was used to identify relevant citations from January 1998 through July 2024. This systematic review was conducted in adherence with PRISMA guidelines. Data were extracted and analyzed descriptively. A meta-analysis calculated the pooled proportions of mortality, hospital admission, intensive care unit (ICU) admission, intubation and mechanical ventilation, and emergency surgery.
Results:
Reviewers screened 3,731 titles and abstracts and 173 full texts. Seventy-five articles from 22 countries were included for analysis. Only 14.7% of included articles came from low-income countries (LICs). Sixty percent of studies were conducted in tertiary care hospitals. The mean proportion of patients who were admitted was 52.1% (95% CI, 0.376 to 0.664). Among all in-patients, 20.0% (95% CI, 0.124 to 0.288) were admitted to an ICU. Overall, 38.0% (95% CI, 0.256 to 0.513) of in-patients underwent emergency surgery and 13.8% (95% CI, 0.023 to 0.315) were intubated. Pooled in-patient mortality was 9.5% (95% CI, 0.046 to 0.156) and total hospital mortality (including emergency department [ED] mortality) was 7.4% (95% CI, 0.034 to 0.124). There were no significant differences in mortality when stratified by country income level or hospital setting.
Conclusion:
Findings from this systematic review can be used to guide preparedness and resource allocation for acute care facilities. Pooled proportions for mortality and other outcomes described in the meta-analysis offer a metric by which future researchers can assess the impact of blast events. Under-representation of LICs and non-tertiary care medical facilities and significant heterogeneity in data reporting among published studies limited the analysis.
In response to the COVID-19 pandemic, we rapidly implemented a plasma coordination center, within two months, to support transfusion for two outpatient randomized controlled trials. The center design was based on an investigational drug services model and a Food and Drug Administration-compliant database to manage blood product inventory and trial safety.
Methods:
A core investigational team adapted a cloud-based platform to randomize patient assignments and track inventory distribution of control plasma and high-titer COVID-19 convalescent plasma of different blood groups from 29 donor collection centers directly to blood banks serving 26 transfusion sites.
Results:
We performed 1,351 transfusions in 16 months. The transparency of the digital inventory at each site was critical to facilitate qualification, randomization, and overnight shipments of blood group-compatible plasma for transfusions into trial participants. While inventory challenges were heightened with COVID-19 convalescent plasma, the cloud-based system, and the flexible approach of the plasma coordination center staff across the blood bank network enabled decentralized procurement and distribution of investigational products to maintain inventory thresholds and overcome local supply chain restraints at the sites.
Conclusion:
The rapid creation of a plasma coordination center for outpatient transfusions is infrequent in the academic setting. Distributing more than 3,100 plasma units to blood banks charged with managing investigational inventory across the U.S. in a decentralized manner posed operational and regulatory challenges while providing opportunities for the plasma coordination center to contribute to research of global importance. This program can serve as a template in subsequent public health emergencies.
Background: After a transient ischemic attack (TIA) or minor stroke, the long-term risk of subsequent stroke is uncertain. Methods: Electronic databases were searched for observational studies reporting subsequent stroke during a minimum follow-up of 1 year in patients with TIA or minor stroke. Unpublished data on number of stroke events and exact person-time at risk contributed by all patients during discrete time intervals of follow-up were requested from the authors of included studies. This information was used to calculate the incidence of stroke in individual studies, and results across studies were pooled using random-effects meta-analysis. Results: Fifteen independent cohorts involving 129794 patients were included in the analysis. The pooled incidence rate of subsequent stroke per 100 person-years was 6.4 events in the first year and 2.0 events in the second through tenth years, with cumulative incidences of 14% at 5 years and 21% at 10 years. Based on 10 studies with information available on fatal stroke, the pooled case fatality rate of subsequent stroke was 9.5% (95% CI, 5.9 – 13.8). Conclusions: One in five patients is expected to experience a subsequent stroke within 10 years after a TIA or minor stroke, with every tenth patient expected to die from their subsequent stroke.
Recently released Moderate-Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) collection 6.1 (C6.1) products are useful for understanding ice–atmosphere interactions over East Antarctica, but their accuracy should be known prior to application. This study assessed Level 2 and Level 3 MODIS C6.1 LST products (MxD11_L2 and MxD11C1) in comparison with the radiance-derived in situ LSTs from 12 weather stations. Significant cloud-related issues were identified in both LST products. By utilizing a stricter filter based on automatic weather station cloud data, despite losing 29.4% of the data, accuracy of MODIS LST was greatly improved. The cloud-screened MODIS LST exhibited cold biases (−5.18 to −0.07°C, and root mean square errors from 2.37 to 6.28°C) than in situ LSTs at most stations, with smaller cold biases at inland stations, but larger ones at coastal regions and the edge of plateau. The accuracy was notably higher during warm periods (October–March) than during cold periods (April–September). The cloud-screened MODIS C6.1 LST did not show significant improvements over C5 (Collection 5) version across East Antarctica. Ice-crystal precipitation occurring during temperature inversions at the surface (Tair-Tsurface) played a crucial role in MODIS LST accuracy on inland plateau. In coastal regions, larger MODIS LST biases were observed when the original measurements were lower.
Identifying neuroimaging biomarkers of antidepressant response may help guide treatment decisions and advance precision medicine.
Aims
To examine the relationship between anhedonia and functional neurocircuitry in key reward processing brain regions in people with major depressive disorder receiving aripiprazole adjunct therapy with escitalopram.
Method
Data were collected as part of the CAN-BIND-1 study. Participants experiencing a current major depressive episode received escitalopram for 8 weeks; escitalopram non-responders received adjunct aripiprazole for an additional 8 weeks. Functional magnetic resonance imaging (on weeks 0 and 8) and clinical assessment of anhedonia (on weeks 0, 8 and 16) were completed. Seed-based correlational analysis was employed to examine the relationship between baseline resting-state functional connectivity (rsFC), using the nucleus accumbens (NAc) and anterior cingulate cortex (ACC) as key regions of interest, and change in anhedonia severity after adjunct aripiprazole.
Results
Anhedonia severity significantly improved after treatment with adjunct aripiprazole.
There was a positive correlation between anhedonia improvement and rsFC between the ACC and posterior cingulate cortex, ACC and posterior praecuneus, and NAc and posterior praecuneus. There was a negative correlation between anhedonia improvement and rsFC between the ACC and anterior praecuneus and NAc and anterior praecuneus.
Conclusions
Eight weeks of aripiprazole, adjunct to escitalopram, was associated with improved anhedonia symptoms. Changes in functional connectivity between key reward regions were associated with anhedonia improvement, suggesting aripiprazole may be an effective treatment for individuals experiencing reward-related deficits. Future studies are required to replicate our findings and explore their generalisability, using other agents with partial dopamine (D2) agonism and/or serotonin (5-HT2A) antagonism.
The proposal of improving reproducibility by lowering the significance threshold to 0.005 has been discussed, but the impact on conducting clinical trials has yet to be examined from a study design perspective. The impact on sample size and study duration was investigated using design setups from 125 phase II studies published between 2015 and 2022. The impact was assessed using percent increase in sample size and additional years of accrual with the medians being 110.97% higher and 2.65 years longer respectively. The results indicated that this proposal causes additional financial burdens that reduce the efficiency of conducting clinical trials.
To improve contact tracing for healthcare workers, we built and configured a Bluetooth low-energy system. We predicted close contacts with great accuracy and provided an additional contact yield of 14.8%. This system would decrease the effective reproduction number by 56% and would unnecessarily quarantine 0.74% of employees weekly.
According to CEOWORLD Magazine‘s 2019 “Health Care Indicators” rating of 89 countries in the world, Taiwan ranks first in the world. The coverage of the National Health Insurance covers all necessary medical treatment, including outpatient, hospitalization, and prescription drugs etc. The psychiatrist was wondering which item with the highest service cost–performance (CP) ratio of the psychiatrist performance in a general hospital and used proportion of PPF as performance indicator. He used allocation to distribute the hours across job activities.
Objectives
The purpose of this study is to investigate items allocation proportion for outpatient and inpatient ward in a specific month, examining the distribution of performance and figure out an appropriate model to optimal medical service.
Methods
Demographic data were collected through PPF projects included 15 outpatient items and 19 inpatient ward items from the third-month of the psychiatrist’s employment in the general hospital, as shown in Table 1. Items related to physiological examination has been excluded. The performance is calculated by combining outpatient and inpatient wards.
Results
Demographic data analysis found that proportion of inpatient ward PPF (67.01%) was significantly greater than proportion of outpatient PPF (32.99%) (Figure 1). The inpatient ward performance was 2 times the outpatient performance. This result showed that most performance came from inpatient ward. Among all items of the proportion of PPF unit, the highest two for inpatient ward items were general hospital bed inpatient consultation (32.58%) and special treatment for psychiatric inpatients (14.35%), and for outpatient, the highest was psychiatric outpatient consultation - more than two (11.31%) (Table 1).
Image:
Image 2:
Conclusions
National Health Insurance is an important system to assist in epidemic prevention during the COVID-19 period. The most PPF of psychiatrist service in a general hospital came from the service of inpatient ward items, including the general hospital bed inpatient consultation with the highest CP ratio. These findings may suggest that the inpatient service could offer psychiatrists fair PPF, and the hospital environment could be favorable for recruitment.
TDuring COVID-19 pandemic, it was noticed that it was students who were mostly affected by the changes that aroused because of the pandemic. The interesting part is whether students’ well-being could be associated with their fields of study as well as coping strategies.
Objectives
In this study, we aimed to assess 1) the mental health of students from nine countries with a particular focus on depression, anxiety, and stress levels and their fields of study, 2) the major coping strategies of students after one year of the COVID-19 pandemic.
Methods
We conducted an anonymous online cross-sectional survey on 12th April – 1st June 2021 that was distributed among the students from Poland, Mexico, Egypt, India, Pakistan, China, Vietnam, Philippines, and Bangladesh. To measure the emotional distress, we used the Depression, Anxiety, and Stress Scale-21 (DASS-21), and to identify the major coping strategies of students - the Brief-COPE.
Results
We gathered 7219 responses from students studying five major studies: medical studies (N=2821), social sciences (N=1471), technical sciences (N=891), artistic/humanistic studies (N=1094), sciences (N=942). The greatest intensity of depression (M=18.29±13.83; moderate intensity), anxiety (M=13.13±11.37; moderate intensity ), and stress (M=17.86±12.94; mild intensity) was observed among sciences students. Medical students presented the lowest intensity of all three components - depression (M=13.31±12.45; mild intensity), anxiety (M=10.37±10.57; moderate intensity), and stress (M=13.65±11.94; mild intensity). Students of all fields primarily used acceptance and self-distraction as their coping mechanisms, while the least commonly used were self-blame, denial, and substance use. The group of coping mechanisms the most frequently used was ‘emotional focus’. Medical students statistically less often used avoidant coping strategies compared to other fields of study. Substance use was only one coping mechanism that did not statistically differ between students of different fields of study. Behavioral disengagement presented the highest correlation with depression (r=0.54), anxiety (r=0.48), and stress (r=0.47) while religion presented the lowest positive correlation with depression (r=0.07), anxiety (r=0.14), and stress (r=0.11).
Conclusions
1) The greatest intensity of depression, anxiety, and stress was observed among sciences students, while the lowest intensity of those components was found among students studying medicine.
2) Not using avoidant coping strategies might be associated with lower intensity of all DASS components among students.
3) Behavioral disengagement might be strongly associated with greater intensity of depression, anxiety, and stress among students.
4) There was no coping mechanism that provided the alleviation of emotional distress in all the fields of studies of students.
Bipolar disorder (BD) is a source of marked disability, morbidity, and premature death. There is a paucity of research on personalized psychosocial interventions for BD, especially in lowresource settings. A previously published pilot randomized controlled trial (RCT) of a Culturally adapted PsychoEducation (CaPE) intervention for BD in Pakistan reported higher patient satisfaction, enhanced medication adherence, knowledge and attitudes towards BD, and improvement in mood symptom scores and health-related quality of life measures compared to treatment-as-usual (TAU).
Objectives
This protocol describes a larger multicentre RCT to confirm the clinical and cost-effectiveness of CaPE in Pakistan.
Methods
A multicentre individual, parallel arm, RCT of CaPE in 300Pakistani adults with BD. Participants over the age of 18, with adiagnosis of bipolar I and II and who are currently euthymic, will berecruited from seven sites including Karachi, Lahore, Multan, Rawalpindi,Peshawar, Hyderabad and Quetta. Time to recurrence will be the primaryoutcome assessed using Longitudinal Interval Follow-up Evaluation(LIFE). Secondary measures will include mood symptomatology, qualityof life and functioning, adherence to psychotropic medications, andknowledge and attitudes towards BD.
Results
Full ethics approval has been received from National Bioethics Committee (NBC) of Pakistan and Centre for Addiction and Mental Health (CAMH), Toronto, Canada. The study has completed sixty-five screening across the seven centres, of which forty-eight participants have been randomised.
Conclusions
A successful trial will lead to rapid implementation of CaPE in clinical practice, not only in Pakistan, but also in other low-resource settings including those in high-income countries, to improve clinical outcomes, social and occupational functioning, and quality of life in South Asian and other minority patients with BD.
In Taiwan, National Health Insurance has been implemented for 27 years and continues to receive international recognition. People pay part of the quota at the time of medical treatment, and the rest of the medical expenses will be paid by the national health insurance. In this study, the researcher, a psychiatrist in the general hospital, investigated the correlation between service and revenue. He has started to work in this hospital since November 1st, 2021, without any other psychiatrist peers.
Objectives
This study used proportion of PPF as performance indicator and aimed to observe the changes of PPF unit from November 1st, 2021, to January 31st, 2022, examining the trend of PPF growth. The purpose is to figure out an appropriate model to optimize medical services and performance outcomes.
Methods
Demographic data were collected through PPF projects, consisting of 17 inpatient ward items and 14 outpatient items from November 1st, 2021, to January 31st, 2022, and items with no performance or related to physiological examination has been excluded. In addition, items with a ratio of greater than 1.5% are presented in the bar graphs, as shown in Figure 2 and 3. The performance proportion of inpatient ward and outpatient were calculated separately.
Results
Demographic data found PPF rises significantly over time (Figure 1). The 2nd month PPF unit (27.09%) was 2.5 times the 1st month PPF unit (10.70%), and the 3rd month PPF unit (62.21%) was 2.2 times the 2nd month PPF unit (27.085%). The highest proportion of PPF items were general hospital bed inpatient consultation fee for inpatient ward item (Figure 2) and psychiatric outpatient consultation fee for outpatient item (Figure 3). Furthermore, only the proportion of psychiatric outpatient consultation – more than two consecutive transfers increased continuously and the proportion of psychiatric outpatient consultation – adjusted by the hospital decreased, the other items has not changed significantly.
Image:
Image 2:
Image 3:
Conclusions
In the first three months of the psychiatrist employment, the performance showed an increasing trend. These findings may suggest that the psychiatrist could be competent in a general hospital with patients’ confidence. In addition, under an optimal model of PPF and medical service, psychiatrists would more like to work in the general hospital, to serve acute psychiatric patients in need.
The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
We investigate the diversity in the sizes and average surface densities of the neutral atomic hydrogen (H i) gas discs in $\sim$280 nearby galaxies detected by the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY). We combine the uniformly observed, interferometric H i data from pilot observations of the Hydra cluster and NGC 4636 group fields with photometry measured from ultraviolet, optical, and near-infrared imaging surveys to investigate the interplay between stellar structure, star formation, and H i structural parameters. We quantify the H i structure by the size of the H i relative to the optical disc and the average H i surface density measured using effective and isodensity radii. For galaxies resolved by $>$$1.3$ beams, we find that galaxies with higher stellar masses and stellar surface densities tend to have less extended H i discs and lower H i surface densities: the isodensity H i structural parameters show a weak negative dependence on stellar mass and stellar mass surface density. These trends strengthen when we limit our sample to galaxies resolved by $>$2 beams. We find that galaxies with higher H i surface densities and more extended H i discs tend to be more star forming: the isodensity H i structural parameters have stronger correlations with star formation. Normalising the H i disc size by the optical effective radius (instead of the isophotal radius) produces positive correlations with stellar masses and stellar surface densities and removes the correlations with star formation. This is due to the effective and isodensity H i radii increasing with mass at similar rates while, in the optical, the effective radius increases slower than the isophotal radius. Our results are in qualitative agreement with previous studies and demonstrate that with WALLABY we can begin to bridge the gap between small galaxy samples with high spatial resolution H i data and large, statistical studies using spatially unresolved, single-dish data.
As a typical plasma-based optical element that can sustain ultra-high light intensity, plasma density gratings driven by intense laser pulses have been extensively studied for wide applications. Here, we show that the plasma density grating driven by two intersecting driver laser pulses is not only nonuniform in space but also varies over time. Consequently, the probe laser pulse that passes through such a dynamic plasma density grating will be depolarized, that is, its polarization becomes spatially and temporally variable. More importantly, the laser depolarization may spontaneously take place for crossed laser beams if their polarization angles are arranged properly. The laser depolarization by a dynamic plasma density grating may find application in mitigating parametric instabilities in laser-driven inertial confinement fusion.
Meat quality is not only influenced by breed but also rearing environment. The aim of this study was to evaluate the influence of different housing environments on growth performance, carcase traits, meat quality, physiological response pre-slaughter and fatty acid composition in two pig breeds. A total of 120 growing pigs at 60-70 days of age were arranged in a 2 × 2 factorial design with the breeds (Duroc × Landrace × Large White [D × L × LW] and Duroc × Landrace × Min pig [D × L × M]) and environmental enrichment (barren concrete floor or enriched with straw bedding) as factors. Each treatment was performed in triplicate with ten pigs per replicate. The pigs housed in the enriched environment exhibited a higher average daily gain, average daily feed intake, saturated fatty acid percentage and backfat depth than the pigs reared in the barren environment. Plasma cortisol levels were lower and growth hormone higher in enriched compared to barren pens. The D × L × M pigs showed lower cooking loss compared with the D × L × LW pigs. Moreover, the D × L × M pigs exhibited poor growth performance but had a better water-holding capacity. Only carcase traits and meat quality interaction effects were observed. We concluded that an enriched environment can reduce preslaughter stress and improve the growth performance of pigs and modulate the fatty acid composition of pork products.
The physics behind the transitions of natural Samaras, or the bio-inspired counterparts, to steady autorotation has been unclear. Theoretical and experimental investigations explore the inertial and aerodynamic characteristics required to guarantee stable transitions of an artificial Samara-like decelerator from chaotic tumbling motions to azimuthal autorotation. A non-dimensional inertial criterion is proposed, which is in accord with experiments.
We present the Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY) Pilot Phase I Hi kinematic models. This first data release consists of Hi observations of three fields in the direction of the Hydra and Norma clusters, and the NGC 4636 galaxy group. In this paper, we describe how we generate and publicly release flat-disk tilted-ring kinematic models for 109/592 unique Hi detections in these fields. The modelling method adopted here—which we call the WALLABY Kinematic Analysis Proto-Pipeline (WKAPP) and for which the corresponding scripts are also publicly available—consists of combining results from the homogeneous application of the FAT and 3DBarolo algorithms to the subset of 209 detections with sufficient resolution and $S/N$ in order to generate optimised model parameters and uncertainties. The 109 models presented here tend to be gas rich detections resolved by at least 3–4 synthesised beams across their major axes, but there is no obvious environmental bias in the modelling. The data release described here is the first step towards the derivation of similar products for thousands of spatially resolved WALLABY detections via a dedicated kinematic pipeline. Such a large publicly available and homogeneously analysed dataset will be a powerful legacy product that that will enable a wide range of scientific studies.
We present WALLABY pilot data release 1, the first public release of H i pilot survey data from the Wide-field ASKAP L-band Legacy All-sky Blind Survey (WALLABY) on the Australian Square Kilometre Array Pathfinder. Phase 1 of the WALLABY pilot survey targeted three $60\,\mathrm{deg}^{2}$ regions on the sky in the direction of the Hydra and Norma galaxy clusters and the NGC 4636 galaxy group, covering the redshift range of $z \lesssim 0.08$. The source catalogue, images and spectra of nearly 600 extragalactic H i detections and kinematic models for 109 spatially resolved galaxies are available. As the pilot survey targeted regions containing nearby group and cluster environments, the median redshift of the sample of $z \approx 0.014$ is relatively low compared to the full WALLABY survey. The median galaxy H i mass is $2.3 \times 10^{9}\,{\rm M}_{{\odot}}$. The target noise level of $1.6\,\mathrm{mJy}$ per 30′′ beam and $18.5\,\mathrm{kHz}$ channel translates into a $5 \sigma$ H i mass sensitivity for point sources of about $5.2 \times 10^{8} \, (D_{\rm L} / \mathrm{100\,Mpc})^{2} \, {\rm M}_{{\odot}}$ across 50 spectral channels (${\approx} 200\,\mathrm{km \, s}^{-1}$) and a $5 \sigma$ H i column density sensitivity of about $8.6 \times 10^{19} \, (1 + z)^{4}\,\mathrm{cm}^{-2}$ across 5 channels (${\approx} 20\,\mathrm{km \, s}^{-1}$) for emission filling the 30′′ beam. As expected for a pilot survey, several technical issues and artefacts are still affecting the data quality. Most notably, there are systematic flux errors of up to several 10% caused by uncertainties about the exact size and shape of each of the primary beams as well as the presence of sidelobes due to the finite deconvolution threshold. In addition, artefacts such as residual continuum emission and bandpass ripples have affected some of the data. The pilot survey has been highly successful in uncovering such technical problems, most of which are expected to be addressed and rectified before the start of the full WALLABY survey.