A control-based observer approach for estimating energy intake during pregnancy.

Gestational weight gain outside of Institute of Medicine guidelines poses a risk to both the mother and her unborn child. Behavioral interventions such as Healthy Mom Zone (HMZ) that aim to regulate gestational weight gain require self-monitoring of energy intake, which is often significantly under-reported by participants. This paper describes the use of a control systems approach for energy intake estimation during pregnancy. It relies on an energy balance model that predicts gestational weight based on physical activity and energy intake, the latter treated as an unmeasured disturbance. Two control-based observer formulations relying on Internal Model Control and Model Predictive Control, respectively, are presented in this paper, first for a hypothetical participant, then on data collected from four HMZ participants. Results demonstrate the effectiveness of the method, with generally best results obtained when estimating energy intake over a weekly time period.

Using SIR Epidemic Modeling and Control to Teach Process Dynamics and Control to Chemical Engineers.

The COVID-19 pandemic has brought about unprecedented opportunities to introduce control systems topics in the undergraduate engineering curriculum. This paper describes two computer modeling assignments based on MATLAB with Simulink developed for CHE 461: Process Dynamics and Control taught at Arizona State University during the fall 2020 semester. A myriad of important concepts, among these dynamic modeling using conservation and accounting principles, linearization, state-space system and transfer function model representations, PID feedback control and Internal Model Control design can be applied to the problem and explained to students in the context of a significant world event representing a unique "process" system, notably the COVID-19 pandemic.

Teaching Control during the COVID-19 Pandemic.

This paper aims to analyze some different solutions that were adopted in control education activities during the pandemic. The authors of this paper are educators in the control education field from different countries on all the continents, who have developed a questionnaire with the idea of collecting data about the COVID-19 pandemic impact on the control education activities. The main objective is to study the diverse alternatives that were used worldwide to perform the online educational activities during that period, such as methodologies, tools, learning management systems (LMS), theoretical exercises, laboratory experiments, types of exams, simulators, software for online lecturing, etc. As a result, comparisons between pre-and during-pandemic educational resources and methods are performed, where useful ideas and discussions are given for the control education community.

Genomic epidemiology of the emerging pathogen Batrachochytrium dendrobatidis from native and invasive amphibian species in Chile.

Emerging fungal diseases represent a threat to food security, animal and human health worldwide. Amphibian chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has been associated with catastrophic and well-documented amphibian population declines and extinctions. For the first time, Bd was cultured from native and non-native wild amphibians in Chile. Phylogenomic analyses revealed that Chilean isolates AVS2, AVS4 and AVS7 group within the global panzootic lineage of Bd (BdGPL) in a single highly supported clade that includes a genotype previously isolated from the United Kingdom. Our results extend the known distribution of BdGPL in South America and suggest a single and relatively recent introduction of BdGPL into the country, providing additional support to the role of anthropogenic activity in the global spread of this panzootic lineage.

Interaction of N-nitrosodiethylamine/bovine serum albumin complexes with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine monolayers at the air-water interface.

We report the effect of N-nitrosodiethylamine (NDA) on the interaction between bovine serum albumin (BSA) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine monolayers (DPPC) at the air-water interface. We prepared aqueous solutions of NDA/BSA complexes maintaining a constant concentration of BSA of 1.49 x 10(-9) M and using NDA concentrations to obtain 2000, 4000, 6000, 12,500, and 25,000 NDA/BSA molar ratios. The hysteresis area and the compressional modulus of the compression-expansion cycles performed at different times were dependent on the NDA concentration. The cycles performed demonstrate the stability of the new phase of DPPC/BSA and DPPC/NDA/BSA monolayers. This was achieved probably because the BSA concentration used was lower than the one needed for BSA to inhibit the return of DPPC molecules to the interface. Results of the compressional modulus at the onset of the new phase, obtained around 17 mN/m, 15 min and 1, 3, 5, and 12 h after DPPC deposition, indicated that the 3.0 x 10(-6) M NDA concentration produced a more rigid film, probably due to the higher alpha-helix content of BSA. AFM images were obtained for DPPC/BSA and two DPPC/NDA/BSA complexes. Our images show that 12,500 NDA/BSA molecules were mostly adsorbed in the liquid condensed phase. However, BSA molecules were distributed more homogeneously.

Lymphoma arising in an S-pouch after total proctocolectomy for ulcerative colitis: report of a case.

The gastrointestinal tract is the most common extranodal site of primary non-Hodgkin's lymphoma. We present a case of a 50-year-old male with primary B cell lymphoma arising in an S-pouch eight years after a total proctocolectomy for ulcerative colitis. After chemoradiotherapy the patient remained asymptomatic, with an intact S-pouch. Pouch conservation is feasible in patients with primary lymphoma of the pouch, using chemoradiotherapy and close follow-up examinations.

Splenic flexure volvulus in association with Chilaiditi syndrome: report of a case.

Hepatodiaphragmatic interposition of the intestine, or Chilaiditi syndrome, is uncommon and typically asymptomatic, but it can be associated with symptoms ranging from intermittent, mild abdominal pain to acute intestinal obstruction. Factors such as the interruption or absence of peritoneal attachments and redundant colon with a long mesentery predispose to both Chilaiditi syndrome and colonic volvulus. The presence of hepatodiaphragmatic interposition of the intestine requires no specific treatment in the absence of symptoms. Colonic volvulus in association with Chilaiditi syndrome is treated based on the location of the volvulus. Volvulus of the splenic flexure is typically treated with resection and primary anastomosis. We report only the third case of colonic volvulus in association with Chilaiditi syndrome and the first with volvulus of the splenic flexure.

Giant colonic diverticulum: report of a case.

Giant colonic diverticulum is a rare complication of colonic diverticulosis. It typically occurs as a single diverticulum located on the antimesenteric border of the sigmoid colon. The most widely accepted theory for its development attributes the progressive dilation to a "ball-valve" mechanism, allowing air to enter but not to exit. Patients usually present complaining of abdominal pain and/or an abdominal mass, although they may remain asymptomatic. Physical examination reveals a tympanic abdominal mass that appears as a round radiolucency on plain radiographs and CT. Barium enema demonstrates the relationship of the diverticulum to bowel and may document communication with the colonic lumen. To alleviate symptoms and prevent complications, the recommended treatment is excision of the diverticulum in continuity with the involved colonic segment. We report a case and discuss the presentation, diagnosis, and management of giant colonic diverticulum.

Biliary dyskinesia: natural history and surgical results.

Patients with biliary dyskinesia have symptoms consistent with biliary colic and an abnormal gallbladder ejection fraction (GEF) in the absence of cholelithiasis. Cholecystokinin hepatobiliary scan quantifies gallbladder function and may assist in selecting patients with acalculous biliary pain who would benefit from cholecystectomy. Seventy-eight patients with an abnormal GEF (< 35%) on cholecystokinin hepatobiliary scan without cholelithiasis were studied retrospectively. Patients were divided into groups based on diagnosis and treatment. In Group I, the patients who underwent cholecystectomy, 80 per cent (35 of 44) had complete symptomatic resolution whereas the remaining 20 per cent (9 of 44) had symptomatic improvement. Pathology reports demonstrated chronic cholecystitis in 95 per cent of specimens. Group II were patients with symptoms attributable to biliary dyskinesia, but did not undergo cholecystectomy. Persistence of symptoms was noted in 75 per cent (18 of 24) of patients whereas 25 per cent (6 of 24) had symptomatic resolution without any treatment. Group III consisted of patients with an abnormal ejection fraction who had improvement of symptoms after treatment for an alternative diagnosis (n = 10). These findings suggest that an abnormal ejection fraction does not always indicate gallbladder disease. Alternative diagnoses must be investigated and treated. Patients with persistent biliary type symptoms in combination with an abnormal GEF in the absence of other attributable causes can expect a favorable response to cholecystectomy.

Prognostic factors for adenocarcinoma of the gallbladder: an analysis of 162 cases.

Carcinoma of the gallbladder is a rare neoplasm and is associated with a dismal prognosis. To analyze the natural history of this disease and prognostic factors, a large tumor registry database was accessed. During the period 1972 to 1995, 214 patients were entered. Adequate follow-up was available on 162 patients, and this group forms the basis of this review. There were 54 males and 108 females with a median age of 62 years. Median follow-up was 7 months. Right upper quadrant abdominal pain was the most frequent presenting symptom. Fifteen patients had an incidental finding of carcinoma after cholecystectomy. Overall, 5-year survival was 25 per cent, with a median survival time of 9.7 months. Survival was improved for patients with local disease compared with those with regional or metastatic disease. One hundred nine patients underwent surgical therapy. Complete resection was possible in 36 patients, whereas 44 patients had residual disease. Median survival time for patients with no residual disease was 67.2 months, whereas those for patients with microscopic residual tumor and gross residual tumor were 8.9 and 3.8 months, respectively (P < 0.000001). Gallbladder cancer is often diagnosed at an advanced stage and is associated with a poor prognosis. In patients with localized disease, surgical treatment provides the opportunity for long-term survival only when a complete resection can be performed. Prognosis for patients with microscopic residual and gross residual disease is similar.

Occult primary adenocarcinoma with axillary metastases.

The medical charts of 20 women with occult primary adenocarcinoma with axillary metastases were reviewed. An extensive radiologic workup in search of the primary lesion had a less than 7 percent positivity rate in the 74 studies carried out. Eleven patients were treated with mastectomy, 5 of whom were found to have carcinoma (49 percent). Four of the 11 patients, all with 14 or more positive axillary lymph nodes, died from breast cancer. Seven patients with no evidence of disease had an average of 4.6 positive axillary lymph nodes. Seven patients did not receive mastectomy, and one died from breast cancer. There was no significant difference in survival between the group treated with mastectomy and the group treated with axillary dissection. We conclude that mastectomy is unnecessary for patients with adenocarcinoma in axillary nodes but no apparent primary tumor.