If you have been reading about cake collapse and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-11-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
Secondary drying removes bound water that remains after ice sublimation. Shelf temperature is raised gradually while pressure remains low, reducing water content to a target range. Over-drying can cause brittleness or electrostatic issues, while under-drying affects stability. The endpoint is often judged by pressure rise tests, temperature measurements, or water content analysis. Scale-up depends on matching heat and mass transfer across equipment sizes. Small changes in shelf temperature or pressure can alter cycle length substantially.
Lyophilization, or freeze-drying, removes water from a material by freezing it and then lowering pressure so ice changes directly to vapor. The process relies on sublimation, the phase transition from solid to gas without an intervening liquid state. It is used for heat-sensitive materials that would degrade in conventional drying. The three stages are freezing, primary drying, and secondary drying, each with distinct temperature and pressure requirements. In practice, cycle design balances these variables.
Misconceptions about lyophilization include the idea that dried products are indefinitely stable or that vacuum sealing eliminates all degradation. Chemical reactions can continue in the solid state, and some proteins lose activity even at low moisture. Another misconception is that any freeze-dryer cycle can be scaled by time alone; heat and mass transfer differ with equipment and load. Open questions remain about predicting long-term stability from short accelerated studies, particularly for amorphous formulations. Real-time stability data remain the standard for shelf-life assignment.
After lyophilization, the dried product is often sealed under vacuum or an inert gas to limit moisture and oxygen exposure. Vials, stoppers, and seals must maintain their barrier throughout shelf life. Storage temperature depends on product sensitivity: some cakes tolerate controlled room temperature, while labile biologics require refrigeration. Humidity is a critical variable because dried cakes are hygroscopic and can absorb water when exposed to air. Handling procedures therefore limit open-vial time and use desiccated environments for sampling.
Quality control for lyophilized materials examines appearance, reconstitution time, residual moisture, and mechanical integrity. An acceptable cake is usually uniform and porous, though appearance alone does not prove stability. Karl Fischer titration is a common method for water content, while differential scanning calorimetry can reveal glass transition events. Stability studies track potency, aggregation, and moisture over time under defined temperature and humidity conditions. Specifications are product-specific and may include sterility and endotoxin tests for sterile preparations.
| Property | Value | Notes |
|---|---|---|
| Process name | Lyophilization or freeze-drying | Both terms appear in technical standards and literature. |
| Phase transition | Sublimation | Solid ice becomes vapor without a liquid step. |
| Typical chamber pressure | 0.05-0.5 mbar | Range depends on product temperature and equipment. |
| Typical product temperature | -40 °C to -10 °C | Measured during primary drying; formulation sets limits. |
| Water content after drying | 0.5-3% w/w | Target varies by material and stability needs. |
While slavery had technically been banned by colonial France in French West Africa (including Mauritania) already in 1905, this had been a purely nominal ban. The 1981 ban on slavery was not enforced in practice, as legal mechanisms to prosecute those who used slaves were not implemented until 2007.
Weinberg's statement is true as far as it goes, but it is not the whole truth. To make it the whole truth, we must add an additional clause: "And for bad people to do good things – that [also] takes religion." The main point of Christianity is that it is a religion for sinners. Jesus made that very clear. When the Pharisees asked his disciples, "Why eateth your Master with publicans and sinners?" he said, "I come to call not the righteous but sinners to repentance." Only a small fraction of sinners repent and do good things but only a small fraction of good people are led by their religion to do bad things. Dyson identified himself as agnostic about some of the specifics of his faith. For example, in reviewing The God of Hope and the End of the World by John Polkinghorne, Dyson wrote:
A 2025 evidence summary for family physicians concluded that, in people with type 2 diabetes, weekly insulin icodec lowers hemoglobin A1c similarly to daily long-acting insulin glargine or degludec, while noting limited data in people or situations at higher risk for hypoglycemia.
88 percent of teleost species are gonochoristic, having individuals that remain either male or female throughout their adult lives. The sex of an individual can be determined genetically as in birds and mammals, or environmentally as in reptiles. In some teleosts, both genetics and the environment play a role in determining sex. For species whose sex is determined by genetics, it can come in three forms. In monofactorial sex determination, a single-locus determines sex inheritance. Both the XY sex-determination system and ZW sex-determination system exist in teleost species. Some species, such as the southern platyfish, have both systems and a male can be determined by XY or ZZ depending on the population. Multifactorial sex determination occurs in numerous Neotropical species and involves both XY and ZW systems. Multifactorial systems involve rearrangements of sex chromosomes and autosomes. For example, the darter characine has a ZW multifactorial system where the female is determined by ZW1W2 and the male by ZZ. The wolf fish has a XY multifactorial system where females are determined by X1X1X2X2 and the male by X1X2Y. Some teleosts, such as zebrafish, have a polyfactorial system, where there are several genes which play a role in determining sex. Environment-dependent sex determination has been documented in at least 70 species of teleost. Temperature is the main factor, but pH levels, growth rate, density and social environment may also play a role. For the Atlantic silverside, spawning in colder waters creates more females, while warmer waters create more males.
In 1995, Ice-T had a recurring role as vengeful drug dealer Danny Cort on the television series New York Undercover, co-created by Dick Wolf. His work on the series earned him the 1996 NAACP Image Award for Outstanding Supporting Actor in a Drama Series. In 1997, he co-created the short-lived series Players, produced by Wolf. This was followed by a role as pimp Seymour "Kingston" Stockton in Exiled: A Law & Order Movie (1998). These collaborations led Wolf to add Ice-T to the cast of Law & Order: Special Victims Unit. Since 2000, he has portrayed Odafin "Fin" Tutuola, a former undercover narcotics officer transferred to the Special Victims Unit. In 2002, the NAACP awarded Ice-T with a second Image Award, again for Outstanding Supporting Actor in a Drama Series, for his work on Law & Order: SVU. Around 1995, Ice-T co-presented a UK-produced magazine television series on black culture, Baadasss TV. In 1997, Ice-T had a pay-per-view special titled Ice-T's Extreme Babes which appeared on Action PPV, formerly owned by BET Networks. In 1999, Ice-T starred in the HBO film Stealth Fighter as a United States Naval Aviator who fakes his own death, steals an F-117 stealth fighter, and threatens to destroy United States military bases. He also acted in the film Sonic Impact, released the same year. Ice-T made an appearance on the comedy television series Chappelle's Show as himself presenting the award for "Player Hater of the Year" at the "Player-Haters Ball", a parody of his own appearance at the Players Ball. He was dubbed the "Original Player Hater".
Sources: en.wikipedia.org
=== Overexpression in cancers === CUX1 is overexpressed in many cancers. The comprehensive molecular characterization of human colon and rectal cancer performed by The Cancer Genome Atlas (TCGA) ranked CUX1 as the fifth gene on a scale showing a correlation between tumour aggressiveness and gene expression/somatic copy number alterations. TCGA and REMBRANDT data also show shorter survival of glioblastoma patients with high CUX1 mRNA expression (reviewed). In smaller scale studies, immunohistochemical analyses on breast, pancreas and glioblastoma cancers reveal that CUX1 expression inversely correlates with relapse-free and overall survival. An alternative CUX1 transcript that is initiated within intron 20 and codes for a p75 isoform is expressed specifically in the testis and thymus. This transcript was found to be aberrantly expressed in many breast tumour cells lines and breast tumours. Transgenic mice expressing this transcript in mammary epithelial cells were shown to develop mammary tumours with metastasis to the lung.
Dalton's law of partial pressures An empirical law which states that in a mixture of non-reacting gases, the total pressure exerted by all of the gases combined is equal to the sum of the partial pressures exerted by each gas individually.
=== March === 6 March Astronomers report the discovery of GJ 887 d, a super-Earth exoplanet orbiting the nearby red dwarf star GJ 887. Detected using radial velocity measurements, the planet lies within the star's habitable zone. At just 10.7 light-years, this becomes the second-nearest known exoplanet in the habitable zone after Proxima Centauri b. The UK's first long‑distance robotic-assisted surgery is reported to have been performed on a patient located 1,500 miles (2,400km) away in Gibraltar. 9 March – A study published in Geophysical Research Letters reports with statistical confidence that global warming has accelerated since around 2015, with the rate of increase rising from 0.2 °C to about 0.35 °C per decade after accounting for natural variability. The findings suggest the 1.5 °C threshold could be reached before 2030 if current trends continue. 10 March – A study by Vattenfall and Spoor using AI-assisted video monitoring of 2,007 bird flight paths near an offshore turbine at Aberdeen Bay over 19 months reports no confirmed collisions, with observed avoidance behaviour suggesting lower-than-expected impacts of wind turbines on seabirds. 11 March Two separate studies, published in Environmental Research Letters and Nature Communications, show how net negative emissions will need to be sustained for centuries in order to stabilise global climate change. Astronomers report evidence of a likely collision between two planets orbiting the star Gaia20ehk, about 11,000 light years away in the constellation Puppis.
== Board of Schools (BOS) == In 1949, ASCP stablished the Board of Schools (BOS) for accrediting medical technologist programs and published the Essentials of an Acceptable MT School. In 1973, following antitrust litigation by the United States Department of Education, the ASCP Board of Schools became the independent National Accrediting Agency for Clinical Laboratory Sciences.
Sources: en.wikipedia.org
==== Children and adolescents ==== Meta-analyses of short-duration randomized clinical trials have found that SSRI use is related to a higher risk of suicidal behavior in children and adolescents. For instance, a 2004 U.S. Food and Drug Administration (FDA) analysis of clinical trials on children with major depressive disorder found statistically significant increases of the risks of "possible suicidal ideation and suicidal behavior" by about 80%, and of agitation and hostility by about 130%. According to the FDA, the heightened risk of suicidality is within the first one to two months of treatment. The National Institute for Health and Care Excellence (NICE) places the excess risk in the "early stages of treatment", "particularly in the early weeks of treatment". The European Psychiatric Association places the excess risk in the first two weeks of treatment and, based on a combination of epidemiological, prospective cohort, medical claims, and randomized clinical trial data, concludes that a protective effect dominates after this early period. A 2014 Cochrane review found that at six to nine months, suicidal ideation remained higher in children treated with antidepressants compared to those treated with psychological therapy. In 2004, the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom judged fluoxetine (Prozac) to be the only antidepressant that offered a favorable risk-benefit ratio in children with depression, though it was also associated with a slight increase in the risk of self-harm and suicidal ideation.
=== Duterte Day === On March 28, 2023, the Davao City Council passed a resolution declaring every March 28—Duterte's birthday—as "Duterte Day" in recognition for the "great and continuing contribution" of Duterte to the city and the Philippines.
However, Nikau asks Tane to come to the Bay to take care of him. Ari believes Tane is a bad influence on Nikau, and when asked if he felt the same way, Browne stated: "I can understand why he thinks that. Ari knows that Tane does dodgy things to make a living, because that's what Ari used to do. So I guess Ari is worried that Nikau's going to follow in Tane's footsteps, in the same way that Tane followed in his..."
Lung disease: Lung cancer Interstitial lung disease most commonly idiopathic pulmonary fibrosis Complicated tuberculosis Suppurative lung disease: lung abscess, empyema, bronchiectasis, cystic fibrosis Mesothelioma of the pleura Sarcoidosis Heart disease: Any disease featuring chronic hypoxia Cyanotic heart defect (most common cardiac cause) Infective endocarditis Atrial myxoma (benign tumor) Arteriovenous fistula or malformation Gastrointestinal and hepatobiliary: Malabsorption Crohn's disease and ulcerative colitis Cirrhosis, especially in primary biliary cholangitis Hepatopulmonary syndrome, a complication of cirrhosis Others: Graves' disease (autoimmune hyperthyroidism) – in this case, it is known as thyroid acropachy Familial and hereditary clubbing and "pseudoclubbing" (people of African descent often have what appears to be clubbing) Vascular anomalies of the affected arm such as an axillary artery aneurysm (in unilateral clubbing) Primary hypertrophic osteoarthropathy Nail clubbing is not specific to chronic obstructive pulmonary disease (COPD). Therefore, in patients with COPD and significant degrees of clubbing, a search for signs of bronchogenic carcinoma (or other causes of clubbing) might still be indicated.
==== Stratified synthesis ==== In addition to modifying the functionality of the ligands and metals themselves, post-synthetic modification can be used to expand upon the structure of the MOF. Using post-synthetic modification MOFs can be converted from a ordered crystalline material toward a heterogeneous porous material. Using post-synthetic techniques, it is possible for the controlled installation of domains within a MOF crystal which exhibit unique structural and functional characteristics. Core-shell MOFs and other layered MOFs have been prepared where layers have unique functionalization but in most cases are crystallographically compatible from layer to layer.
Sources: en.wikipedia.org
Conventional drying uses heat to evaporate liquid water, often at temperatures that can degrade sensitive materials. Lyophilization freezes the material first and then removes water by sublimation under vacuum. This avoids prolonged exposure to liquid water and high heat.
Lowering pressure reduces the boiling point of water and allows ice to sublimate at temperatures below freezing. Vacuum also limits convective heat transfer, so heat is usually supplied by shelves or radiation. The pressure must stay below the vapor pressure of ice at the product temperature.
The cycle typically includes freezing, primary drying, and secondary drying. Freezing solidifies water and sets the pore structure; primary drying removes bulk ice; secondary drying removes bound water. Some cycles add annealing or pre-freezing steps.
No. Freeze-drying removes water but does not reliably kill microorganisms. Sterile lyophilized products are typically prepared aseptically before freezing or are sterilized by a validated method. Microbial control depends on the entire manufacturing process.