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Objective Calcium is an essential mineral involved in the functioning of nearly every human cell. Calcium levels are regulated by dietary absorption, vitamin D status, and parathyroid hormone (PTH). This report describes a patient in whom childhood bowel resection and partial gastrectomy resulted in malabsorptive hypocalcemia in adulthood. Case Report A 21-year-old man presented with syncope and a fall resulting in a right femoral neck fracture. His medical history included small bowel obstructions at age 9 requiring bowel resection, and at age 12 with gastric perforation and partial gastrectomy. Laboratory values showed calcium level of 4.9 mg/dL (8.9-10.3 mg/dL). PTH level was 273 pg/mL (12.0-88.0 pg/mL), 25-hydroxy-vitamin D was 28 ng/dL (30-100 ng/mL), and 1,25-dihydroxy-vitamin D was 54 pg/dL (18-72 pg/mL). Furthermore, magnesium and phosphorus levels were 2.1 mg/dL (1.5-2.6 mg/dL) and 4.4 mg/dL (2.4-4.7 mg/dL), respectively. Calcium levels improved to 9.5 mg/dL on 10% calcium gluconate drip but could not be maintained above 7 mg/dL on oral calcium carbonate supplementation, despite doses as high as 3750 mg three times daily with calcitriol 0.75 mcg twice daily. After switching from calcium carbonate to calcium citrate 3500 mg three times daily, the calcium level improved and was maintained between 8.3 and 9.0 mg/dL. Discussion High calcium needs, other nutrient deficiencies, and response to calcium citrate versus calcium carbonate suggest malabsorption from achlorhydria and small bowel resection. Conclusion This case emphasizes the gastrointestinal physiology in calcium homeostasis and highlights the recognition of hypocalcemia as a complication of gastric and bowel resection.

A novel approach for simultaneous acid gas enrichment (AGE) and CO2 capture is presented. This new process combines membrane and amine technologies to achieve unprecedented levels of H2S enrichment (>85%) and efficient CO2 capture. Traditionally, acid gas enrichment (AGE) is performed with an H2S-selective amine to elevate the H2S content of an acid gas stream, with the primary objective being to allow for reliable operation of the sulfur recovery unit (SRU). SRUs convert H2S into elemental sulfur and perform better with a high acid gas H2S concentration. The higher the H2S concentration, the higher the temperature in the reaction furnace, leading to complete destruction of hydrocarbons, including aromatics, in the acid gas feed stream that would otherwise have a detrimental effect on the downstream catalyst beds. The amine-based AGE is designed to increase the H2S concentration, preferably above 55%, and up to 70%. At this concentration, the sulfur recovery unit can operate in straight-through mode, and all hydrocarbons and feed stream contaminants are destroyed in the reaction furnace leading to trouble-free catalytic bed operation. The off-gas (i.e., overhead) of the AGE absorber, is a potential source for high purity CO2 (i.e., 98.5%+ CO2-dry basis), but with a CO2 recovery lower than 70%. Our novel approach was designed to further improve both the H2S enrichment process and CO2 capture efficiencies. The new design combines a CO2-over-H2S selective membrane and H2S-selective amine. By its physical and chemical properties, the membrane rejects hydrocarbons, including aromatics, and mercaptans along with H2S in the acid gas stream to the sulfur recovery unit. The membrane permeate contains most of the acid gas CO2 and a small amount of H2S. This membrane permeate stream is sent to an H2S-selective amine to capture H2S, which leads to a high-purity CO2 overhead stream. The CO2 capture rate can exceed 95% with a lower cost than any other commercially available solution. The H2S concentration in the acid gas feed to the SRU can simultaneously exceed 85%, which ensures reliable SRU operation as well as minimizing the size of the required SRU equipment (i.e., reduced capex). An example of the novel technology potential to capture more than 95% of CO2 from the feed of an existing SRU equipped with amine tail gas treatment (TGT) is presented.

INTRODUCTION: The association between diabetic ketoacidosis (DKA) and acute pancreatitis (AP) is well established. Hypercalcemia from primary hyperparathyroidism (PHPT) is a rare cause of AP, accounting for less than one percent of cases. The constellation of PHPT, AP, and DKA as an initial presentation of diabetes is not known. CASE PRESENTATION: A 33-year-old male with minimal prior healthcare contact presented to the ER with acute encephalopathy after three weeks of polyuria and polydipsia, and later abdominal pain, nausea, and vomiting. He was hyperglycemic to 1310 mg/dl with an anion-gap metabolic acidosis (pH 7.12, serum bicarbonate of 7 mEq/L, anion gap of 33) and elevated beta-hydroxybutyrate to greater than 9 mmol/L, and was profoundly dehydrated with hyperosmolarity to 354 mOsm/kg. He was hypercalcemic to 14.0 mg/dl with elevated parathyroid hormone of 260.7 pg/L. CT of the chest, abdomen, and pelvis revealed acute necrotizing pancreatitis. He was treated with insulin, aggressive fluid resuscitation, and supportive measures, with resolution of encephalopathy, DKA, AP, hyperosmolarity, and kidney injury. Calcium and parathyroid hormone remained elevated, with further workup suggesting PHPT as the etiology of his hypercalcemia. DISCUSSION: Associations between PHPT and AP, and between AP and DKA, are established in the literature, but few cases of DKA from hypercalcemia-induced AP have been described. Our patient highlights the importance of the etiologic workup in both DKA and AP, as both carry high mortality and have high rates of recurrence. Further study is needed to better characterize the relationship between DKA, AP, and PHPT to better inform early diagnosis and prevention efforts.

1.9 million housing units in Ireland are required to be retrofitted for the existing Irish national housing stock to be considered nearly zero energy building (nZEB). This paper assesses optimum retrofit packages aimed at improving the building material thermal efficiencies and energy demand of gas-heated semi-detached and end-terraced houses in Ireland. The cost-optimal methodology framework for calculating cost optimal levels of minimum energy performance requirements for buildings and building elements is used to determine the optimum retrofit packages from both a householder perspective and a societal perspective. The results of the cost-optimal approach are compared to the results from a weighted framework approach which incorporates life cycle environmental and cost indicators from both a householder perspective and a societal perspective. The results found that the ranking of energy efficiency retrofit designs based on multiple life cycle environmental and cost indicators differ compared to cost optimum designs based on only life cycle energy and cost indicators. The cost-optimal approach was found to be effective for identifying retrofit packages that are among the best packages even without accounting for multiple environmental indicators. However, once multiple indicators were considered, the hierarchy of the optimal retrofit packages changed. In the Irish context, the environmental impact of the Irish electricity grid was found to play a significant role in the hierarchy of the retrofit packages examined. While the cost-optimal method should not be relied on solely for identifying the optimum retrofit package solution, it could be employed as part of the multistage assessment methodology for narrowing down design solution sample sizes. Using the remaining array of retrofit packages solutions, the optimum retrofit package could be identified using multiple indicators. The authors would like to acknowledge the support of Science Foundation Ireland through the Career Development Award programme (grant no. 13/CDA/2200). The authors would like to acknowledge the support of the European Union's FP7 ERA-NET Sumforest grant programme (grant agreement no. 606803) and the European Union's Horizon 2020 research and innovation programme under grant agreement no 839134. peer-reviewed