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Calcite is the most abundant carbonate mineral in Earth's crust. Upon cleavage, the (10.4) plane with a rectangular unit cell is exposed. Interestingly, several experiments suggest a (2 × 1) surface reconstruction. However, clear experimental evidence and a theoretical confirmation were long missing. Recently, convincing indication for a (2 × 1) reconstruction has been given by atomic force microscopies taken at 5 K. Here, we show temperature-programmed desorption (TPD) experiments of water and ethanol desorbing from calcite (10.4) around room temperature. The TPD curves fit excellently to a kinetic model considering two different adsorption sites, as expected in case of a (2 × 1) reconstruction. This finding applies to the desorption of water and ethanol, illustrating that the effect is characteristic for the calcite cleavage plane. Our results thus show that the (2 × 1) reconstruction not only exists at room temperature but has significant impact on the interfacial properties of calcite.

Treating chronic symptoms for pain and movement disorders with neuromodulation therapies involves fine-tuning of programming parameters over several visits to achieve and maintain symptom relief. This, together with challenges in access to trained specialists, has led to a growing need for an integrated wireless remote care platform for neuromodulation devices. In March of 2021, we launched the first neuromodulation device with an integrated remote programming platform. Here, we summarize the biodesign steps taken to identify the unmet patient need, invent, implement, and test the new technology, and finally gain market approval for the remote care platform. Specifically, we illustrate how agile development aligned with the evolving regulatory requirements can enable patient-centric digital health technology in neuromodulation, such as the remote care platform. The three steps of the biodesign process applied for remote care platform development are: (1) Identify, (2) Invent, and (3) Implement. First, we identified the unmet patient needs through market research and voice-of-customer (VOC) process. Next, during the concept generation phase of the invention step, we integrated the results from the VOC into defining requirements for prototype development. Subsequently, in the concept screening phase, ten subjects with PD participated in a clinical pilot study aimed at characterizing the safety of the remote care prototype. Lastly, during the implementation step, lessons learned from the pilot experience were integrated into final product development as new features. Following final product development, we completed usability testing to validate the full remote care system and collected preliminary data from the limited market release experience. The VOC data, during prototype development, helped us identify thresholds for video quality and needs priorities for clinicians and patients. During the pilot study, one subject reported anticipated remote-care-related adverse events that were resolved without sequelae. For usability analysis following final product development, the failure rates for task completion for both user groups were about 1%. Lastly, during the initial 4 weeks of the limited market release experience, a total of 858 remote care sessions were conducted with a 93% success rate. Overall, we developed a remote care platform by adopting a user-centric approach. Although the system intended to address pre-COVID19 challenges associated with disease management, the unforeseen overlap of the study with the pandemic elevated the importance of such a system and an innovative development process enabled us to advance a patient-centric platform to gain regulatory approval and successfully launch the remote care platform to market., (© 2022. The Author(s).)

Digital health can drive patient-centric innovation in neuromodulation by leveraging current tools to identify response predictors and digital biomarkers. Iterative technological evolution has led us to an ideal point to integrate digital health with neuromodulation. Here, we provide an overview of the digital health building-blocks, the status of advanced neuromodulation technologies, and future applications for neuromodulation with digital health integration., Competing Interests: YP, DL, SD, AB, BB, and ER are employees of Abbott Labs. BP is an employee of Rune Labs. WG and SS serve on the Scientific Advisory Board for Abbott Neuromodulation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Pathak, Greenleaf, Verhagen Metman, Kubben, Sarma, Pepin, Lautner, DeBates, Benison, Balasingh and Ross.)

Background: The chronic cerebrospinal venous insufficiency theory proposes that altered cerebral venous hemodynamics play a role in the pathophysiology of multiple sclerosis. We aimed to explore the validity of this hypothesis by assessing the diagnostic criteria for chronic cerebrospinal venous insufficiency in persons with and without multiple sclerosis., Methods: We compared the proportion of venous outflow abnormalities between patients with multiple sclerosis and healthy controls using extracranial Doppler ultrasonography and gadolinium-enhanced magnetic resonance venography. Interpreting radiologists were blinded to the clinical status of participants., Results: We enrolled 120 patients with multiple sclerosis and 60 healthy controls. High proportions of both patients (67/115 [58%]) and controls (38/60 [63%]) met 1 or more of the proposed ultrasound criteria for diagnosis of chronic cerebrospinal venous insufficiency (p = 0.6). A minority of patients (23/115 [20%]) and controls (6/60 [10%]) fulfilled 2 or more of the proposed criteria (p = 0.1). There were no differences between patients and controls in the prevalence of each individual ultrasound criterion. Similarly, there were no differences in intracranial or extracranial venous patency between groups, as measured by magnetic resonance venography., Interpretation: We detected no differences in the proportion of venous outflow abnormalities between patients with multiple sclerosis and healthy controls. Moreover, our study revealed significant methodologic concerns regarding the proposed diagnostic criteria for chronic cerebrospinal venous insufficiency that challenge their validity., (© 2014 Canadian Medical Association or its licensors.)

Background: Ultrasound (US) examination has many uses in resuscitation, but to use it to its full effectiveness typically requires a trained and proficient user. We sought to use information technology advances to remotely guide US-naive examiners (UNEs) using a portable battery-powered tele-US system mentored using either a smartphone or laptop computer., Materials and Methods: A cohort of UNEs (5 tactical emergency medicine technicians, 10 ski-patrollers, and 4 nurses) was guided to perform partial or complete Extended Focused Assessment with Sonography of Trauma (EFAST) examinations on both a healthy volunteer and on a US phantom, while being mentored by a remote examiner who viewed the US images over either an iPhone(®) (Apple, Cupertino, CA) or a laptop computer with an inlaid depiction of the US probe and the "patient," derived from a videocamera mounted on the UNE's head. Examinations were recorded as still images and over-read from a Web site by seven expert reviewers (ERs) (three surgeons, two emergentologists, and two radiologists). Examination goals were to identify lung sliding (LS) documented by color power Doppler (CPD) in the human and to identify intraperitoneal (IP) fluid in the phantom., Results: All UNEs were successfully mentored to easily and clearly identify both LS (19 determinations) and IP fluid (14 determinations), as assessed in real time by the remote mentor. ERs confirmed IP fluid in 95 of 98 determinations (97%), with 100% of ERs perceiving clinical utility for the abdominal Focused Assessment with Sonography of Trauma. Based on single still CPD images, 70% of ERs agreed on the presence or absence of LS. In 16 out of 19 cases, over 70% of the ERs felt the EFAST exam was clinically useful., Conclusions: UNEs can confidently be guided to obtain critical findings using simple information technology resources, based on the receiving/transmitting device found in most trauma surgeons' pocket or briefcase. Global US mentoring requires only Internet connectivity and initiative.

Background: Ultrasonography is increasingly used for teaching physical examination in medical schools. This study seeks the opinions of educators as to which physical examinations would be most enhanced by the addition of ultrasonography. We also asked when ultrasound-aided physical examination teaching could have deleterious effects if used outside its intended scope., Methods: All of the educators from the University of Calgary Master Teacher Program were invited to complete a 22-item paper-based survey. Survey items were generated independently by two investigators, with input from an expert panel (n = 5)., Results: Of the 36 educators, 27 (75%) completed the survey. Examinations identified to be potentially most useful included: measuring the size of the abdominal aorta, identifying the presence/absence of ascites, identifying the presence/absence of pleural effusions, and measuring the size of the bladder. Examinations thought to be potentially most harmful included: identifying the presence/absence of intrauterine pregnancy, measuring the size of the abdominal aorta, and identifying the presence/absence of pericardial effusion., Conclusions: Examinations that are potentially the most useful may also be potentially the most harmful. When initiating an ultrasound curriculum for physical examinations, educators should weigh the risks and benefits of examinations chosen.

Background: Ultrasound (US) has an ever increasing scope in the evaluation of trauma, but relies greatly on operator experience. NASA has refined telesongraphy (TS) protocols for traumatic injury, especially in reference to mentoring inexperienced users. We hypothesized that such TS might benefit remote terrestrial caregivers. We thus explored using real-time US and video communication between a remote (Banff) and central (Calgary) site during acute trauma resuscitations., Methods: A existing internet link, allowing bidirectional videoconferencing and unidirectional US transmission was used between the Banff and Calgary ERs. Protocols to direct or observe an extended focused assessment with sonography for trauma (EFAST) were adapted from NASA algorithms. A call rota was established. Technical feasibility was ascertained through review of completed checklists. Involved personnel were interviewed with a semistructured interview., Results: In addition to three normal volunteers, 20 acute clinical examinations were completed. Technical challenges requiring solution included initiating US; audio and video communications; image freezing; and US transmission delays. FAST exams were completed in all cases and EFASTs in 14. The critical anatomic features of a diagnostic examination were identified in 98% of all FAST exams and a 100% of all EFASTs that were attempted. Enhancement of clinical care included confirmation of five cases of hemoperitoneum and two pneumothoraces (PTXs), as well as educational benefits. Remote personnel were appreciative of the remote direction particularly when instructions were given sequentially in simple, nontechnical language., Conclusions: The remote real-time guidance or observation of an EFAST using TS appears feasible. Most technical problems were quickly overcome. Further evaluation of this approach and technology is warranted in more remote settings with less experienced personnel.

Strictures of the esophagus represent persistent luminal narrowing following an inflammatory insult to mural tissues or a manifestation of malignant disease. Barium studies remain the cornerstone of evaluation of patients with a suspected stricture. The diagnostic features of the various causes of strictures are discussed. Balloon dilatation and stent placement, as well as other radiologic interventions, often have an important role in the treatment of patients with advanced disease. This article discusses the indications and general application of these procedures as well as the nature and evaluation of the associated complications.

Atrioventricular synchronous pacing offers advantages over fixed-rate ventricular (VVI) pacing both at rest and during exercise. This study compared the hemodynamic effects at rest and exercise of ventricular pacing at a rate of 70 beats/min, ventricular pacing where the rate was increased during exercise and dual chamber pacing. Ten patients, age 63 +/- 8 years, with multiprogrammable DDD pacemakers were studied using supine bicycle radionuclide ventriculography. Radionuclide data during dual chamber pacing was acquired at rest and during a submaximal workload of 200-400 kpm/min. The pacemakers were then programmed to VVI pacing at a rate of 70 beats/min, and 1 week later, studies were repeated in the VVI mode at rest, during exercise at a rate of 70 beats/min, and during exercise with the VVI pacemaker programmed to a rate adapted to the DDD pacing exercise rate. At rest, the cardiac output was lower in the VVI compared with the AV sequential mode (4.1 +/- 1.1 vs 5.7 +/- 1.1 1/min, P less than 0.01). During exercise, the cardiac output increased from resting values in the DDD and VVI pacing modes, however cardiac output in the rate-adapted VVI mode was higher than in the VVI mode with the rate maintained at 70 beats/min (8.1 +/- 1.5 vs 6.3 +/- 1.1 1/min, P = 0.02). Three patients completed lower workloads with VVI pacing at 70 beats/min compared with AV synchronous pacing. At rest, AV sequential pacing was superior to VVI pacing, suggesting the importance of the atrial contribution to ventricular filling. With VVI pacing during exercise, cardiac output was improved with an increased pacemaker rate, suggesting that the heart rate response during exercise was the major determinant of the higher cardiac output.

The effect of oxygen free radicals, generated by xanthine and xanthine oxidase, was studied on the release of lysosomal hydrolase from rat liver lysosomes in vitro. A lysosomal enriched subcellular fraction was prepared, using differential centrifugation technique, from the homogenate of rat liver. The biochemical purity of the lysosomal fraction was established by using the markers of different cellular organelles. Oxygen free radicals were generated in vitro by the addition of xanthine and xanthine oxidase. The release of lysosomal hydrolase (beta-glucuronidase) from the lysosomal fraction was measured. There was a 3 to 4 fold increase in the release of beta-glucuronidase activity in the presence of xanthine and xanthine oxidase when compared to that in the absence of xanthine and xanthine oxidase. In the presence of superoxide dismutase (SOD), a scavenger of oxygen free radicals, the xanthine and xanthine oxidase system was unable to induce the release of beta-glucuronidase activity from the lysosomes. Sonication (2 bursts for 15 sec each) and Lubrol (2 mg/10 mg lysosomal protein) treatment, which are known to cause membrane disruption, also induced the release of beta-glucuronidase from lysosomal fraction. This release of beta-glucuronidase by sonication and lubrol treatment was not prevented by SOD. These data indicate that lysosomal disruption is a consequence of oxygen free radicals, generated by xanthine and xanthine oxidase.